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Interactive effects of chemical and biological controls on food-web composition in saline prairie lakes
Cooper, Ryan N
Wissel, Björn
Aquatic Biosystems
Salinity is restricting habitatability for many biota in prairie lakes due to limited physiological abilities to cope with increasing osmotic stress. Yet, it remains unclear how salinity effects vary among major taxonomic groups and what role other environmental parameters play in shaping food-web composition. To answer these questions, we sampled fish, zooplankton and littoral macroinvertebrates in 20 prairie lakes (Saskatchewan, Canada) characterized by large gradients in water chemistry and lake morphometry. We showed that salinity thresholds differed among major taxonomic groups, as most fishes were absent above salinities of 2 g L-1, while littoral macroinvertebrates were ubiquitous. Zooplankton occurred over the whole salinity range, but changed taxonomic composition as salinity increased. Subsequently, the complexity of fish community (diversity) was associated with large changes in invertebrate communities. The directional changes in invertebrate communities to smaller taxa indicated that complex fish assemblages resulted in higher predation pressure. Most likely, as the complexity of fish community decreased, controls of invertebrate assemblages shifted from predation to competition and ultimately to productivity in hypersaline lakes. Surprisingly, invertebrate predators did not thrive in the absence of fishes in these systems. Furthermore, the here identified salinity threshold for fishes was too low to be a result of osmotic stress. Hence, winterkill was likely an important factor eliminating fishes in low salinity lakes that had high productivity and shallow water depth. Ultimately, while salinity was crucial, intricate combinations of chemical and biological mechanisms also played a major role in controlling the assemblages of major taxonomic groups in prairie lakes.
Lake food-web; Diversity; Fish; Invertebrates; Salinity; Winter kill
Related Articles
Effects of Temperature, Salinity and Fish in Structuring the Macroinvertebrate Community in Shallow Lakes: Implications for Effects of Climate Change
Brucet, Sandra
Boix, Dani
Nathansen, Louise W.
Quintana, Xavier D.
Jensen, Elisabeth
Balayla, David
Meerhoff, Mariana
Jeppesen, Erik
PLoS ONE
Climate warming may lead to changes in the trophic structure and diversity of shallow lakes as a combined effect of increased temperature and salinity and likely increased strength of trophic interactions. We investigated the potential effects of temperature, salinity and fish on the plant-associated macroinvertebrate community by introducing artificial plants in eight comparable shallow brackish lakes located in two climatic regions of contrasting temperature: cold-temperate and Mediterranean. In both regions, lakes covered a salinity gradient from freshwater to oligohaline waters. We undertook day and night-time sampling of macroinvertebrates associated with the artificial plants and fish and free-swimming macroinvertebrate predators within artificial plants and in pelagic areas. Our results showed marked differences in the trophic structure between cold and warm shallow lakes. Plant-associated macroinvertebrates and free-swimming macroinvertebrate predators were more abundant and the communities richer in species in the cold compared to the warm climate, most probably as a result of differences in fish predation pressure. Submerged plants in warm brackish lakes did not seem to counteract the effect of fish predation on macroinvertebrates to the same extent as in temperate freshwater lakes, since small fish were abundant and tended to aggregate within the macrophytes. The richness and abundance of most plant-associated macroinvertebrate taxa decreased with salinity. Despite the lower densities of plant-associated macroinvertebrates in the Mediterranean lakes, periphyton biomass was lower than in cold temperate systems, a fact that was mainly attributed to grazing and disturbance by fish. Our results suggest that, if the current process of warming entails higher chances of shallow lakes becoming warmer and more saline, climatic change may result in a decrease in macroinvertebrate species richness and abundance in shallow lakes.
Related Articles
Assessing element-specific patterns of bioaccumulation across New England lakes
Ward, Darren M.
Mayes, Brandon
Sturup, Stefan
Folt, Carol L.
Chen, Celia Y.
The Science of the Total Environment
Little is known about differences among trace elements in patterns of bioaccumulation in freshwater food webs. Our goal was to identify patterns in bioaccumulation of different elements that are large and consistent enough to discern despite variation across lakes. We measured methylmercury (MeHg) and trace element (As, Cd, Hg, Pb, and Zn) concentrations in food web components of seven New England lakes on 3–5 dates per lake, and contrasted patterns of bioaccumulation across lakes, metals and seasons. In each lake, trace element concentrations were compared across trophic levels, including three size fractions of zooplankton, planktivorous fish, and piscivorous fish. The trophic position of each food web component was estimated from N isotope analysis. Trace element concentrations varied widely among taxa, lakes and sampling dates. Yet, we identified four consistent patterns of bioaccumulation that were consistent across lakes: (1) MeHg concentration increased (i.e., was biomagnified) and Pb concentration decreased (i.e., was biodiminished) with increased trophic position. (2) Zinc concentration (as with MeHg) was higher in fish than in zooplankton, but overall variation in Zn concentration (unlike MeHg) was low. (3) Arsenic and Cd concentrations (as with Pb) were lower in fish than in zooplankton, but (unlike Pb) were not significantly correlated with trophic position within zooplankton or fish groups. (4) Average summer concentrations of As, Pb, Hg, and MeHg in zooplankton significantly predicted their concentrations in either planktivorous or piscivorous fish. Our secondary goal was to review sampling approaches in forty-five published studies to determine the extent to which current sampling programs facilitate cross-lake and cross-study comparisons of bioaccumulation. We found that studies include different components of the food web and sample too infrequently to enable strong cross-lake and cross-study comparisons. We discuss sampling strategies that would improve our capacity to identify consistent patterns of bioaccumulation and drivers of elevated trace element concentrations under naturally high levels of variability.
aquatic food web; biomagnification; fish; mercury; trace metal; trophic transfer; zooplankton
Related Articles
Impact of Forest Harvesting on Trophic Structure of Eastern Canadian Boreal Shield Lakes: Insights from Stable Isotope Analyses
Glaz, Patricia
Sirois, Pascal
Archambault, Philippe
Nozais, Christian
PLoS ONE
Perturbations on ecosystems can have profound immediate effects and can, accordingly, greatly alter the natural community. Land-use such as forestry activities in the Canadian Boreal region have increased in the last decades, raising concerns about their potential impact on aquatic ecosystems. The objective of this study was to evaluate the impact of forest harvesting on trophic structure in eastern Canadian Boreal Shield lakes. We measured carbon and nitrogen stable isotopes values for aquatic primary producers, terrestrial detritus, benthic macroinvertebrates, zooplankton and brook trout (Salvelinus fontinalis) over a three-year period in eight eastern Boreal Shield lakes. Four lakes were studied before, one and two years after forest harvesting (perturbed lakes) and compared with four undisturbed reference lakes (unperturbed lakes) sampled at the same time. Stable isotope mixing models showed leaf-litter to be the main food source for benthic primary consumers in both perturbed and unperturbed lakes, suggesting no logging impact on allochthonous subsidies to the littoral food web. Brook trout derived their food mainly from benthic predatory macroinvertebrates in unperturbed lakes. However, in perturbed lakes one year after harvesting, zooplankton appeared to be the main contributor to brook trout diet. This change in brook trout diet was mitigated two years after harvesting. Size-related diet shift were also observed for brook trout, indicating a diet shift related to size. Our study suggests that carbon from terrestrial habitat may be a significant contribution to the food web of oligotrophic Canadian Boreal Shield lakes. Forest harvesting did not have an impact on the diet of benthic primary consumers. On the other hand, brook trout diet composition was affected by logging with greater zooplankton contribution in perturbed lakes, possibly induced by darker-colored environment in these lakes one year after logging.
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The trophic status of Suwałki Landscape Park lakes based on selected parameters (NE Poland)
Jekatierynczuk-Rudczyk, Elżbieta
Zieliński, Piotr
Grabowska, Magdalena
Ejsmont-Karabin, Jolanta
Karpowicz, Maciej
Więcko, Adam
Environmental Monitoring and Assessment
This study describes changes in the trophic status of 12 lakes within Suwałki Landscape Park (SLP). All of the trophic classifications of the lakes were based on the trophic continuum division. Trophic status was determined by means of multiparameter indices using several diverse criteria. In this study, the assessment of the trophic status of lakes included water quality; abundance and biomass of bacterioplankton, phytoplankton, and zooplankton; and primary production of phytoplankton. The Carlson trophic state index (TSI) describes the level of water fertility and indicated the dominance of moderately eutrophic waters. Lakes Perty, Jeglówek, and Hańcza have a trophic status that indicates mesotrophy (TSI <50). The trophic status of the studied lakes was determined based on the bacterial abundance and clearly showed a lack of oligotrophic lakes in SLP. Based on the number of bacteria, only Lake Szurpiły can be classified as β-mesotrophic, whereas Lake Linówek can be characterized as hypertrophic with some features typical for humic waters. The greatest value of gross primary production was observed in Lake Linówek (126.4 mg C/m3/h). The phytoplankton trophy index varied from 1.59 to 2.28, and its highest value, which indicated eutrophy, was determined for Lake Udziejek. In the case of Lakes Hańcza, Szurpiły, Perty, Jeglówek, and Kojle, the index ranged from 1.25 to 1.74, which indicated mesotrophy. The majority of the lakes were classified as mesoeutrophic (1.75–2.24). The highest trophic status was assessed for lakes with a marked dominance of cyanobacteria (Lake Przechodnie, Lake Krajwelek, Lake Udziejek, and Lake Pogorzałek), which is commonly recognized as an indicator of high trophic status. Considering all of the indices of trophic status, the analysis of rotifer community structure indicates that the studied group of lakes is mesoeutrophic or eutrophic. The values of crustacean zooplankton indices indicated that the trophic status of the studied lakes was close to that determined using a TSI. The parameters of zooplankton abundance and species structure allowed for the observance of changes in the tropic levels of lakes, which are difficult to detect by a chemical assay alone.
Trophic state index; Nutrients; Bacterioplankton; Phytoplankton; Zooplankton; Primary production
Related Articles
Patterns in Benthic Biodiversity Link Lake Trophic Status to Structure and Potential Function of Three Large, Deep Lakes
Hayford, Barbara L.
Caires, Andrea M.
Chandra, Sudeep
Girdner, Scott F.
PLoS ONE
Relative to their scarcity, large, deep lakes support a large proportion of the world's freshwater species. This biodiversity is threatened by human development and is in need of conservation. Direct comparison of biodiversity is the basis of biological monitoring for conservation but is difficult to conduct between large, insular ecosystems. The objective of our study was to conduct such a comparison of benthic biodiversity between three of the world's largest lakes: Lake Tahoe, USA; Lake Hövsgöl, Mongolia; and Crater Lake, USA. We examined biodiversity of common benthic organism, the non-biting midges (Chironomidae) and determined lake trophic status using chironomid-based lake typology, tested whether community structure was similar between the three lakes despite geographic distance; and tested whether chironomid diversity would show significant variation within and between lakes. Typology analysis indicated that Lake Hövsgöl was ultra-oligotrophic, Crater Lake was oligotrophic, and Lake Tahoe was borderline oligotrophic/mesotrophic. These results were similar to traditional pelagic measures of lake trophic status for Lake Hövsgöl and Crater Lake but differed for Lake Tahoe, which has been designated as ultra-oligotrophic by traditional pelagic measures such as transparency found in the literature. Analysis of similarity showed that Lake Tahoe and Lake Hövsgöl chironomid communities were more similar to each other than either was to Crater Lake communities. Diversity varied between the three lakes and spatially within each lake. This research shows that chironomid communities from these large lakes were sensitive to trophic conditions. Chironomid communities were similar between the deep environments of Lake Hövsgöl and Lake Tahoe, indicating that chironomid communities from these lakes may be useful in comparing trophic state changes in large lakes. Spatial variation in Lake Tahoe's diversity is indicative of differential response of chironomid communities to nutrient enrichment which may be an indication of changes in trophic state within and across habitats.
Related Articles
Saline systems of the Great Plains of western Canada: an overview of the limnogeology and paleolimnology
Last, William M
Ginn, Fawn M
Saline Systems
In much of the northern Great Plains, saline and hypersaline lacustrine brines are the only surface waters present. As a group, the lakes of this region are unique: there is no other area in the world that can match the concentration and diversity of saline lake environments exhibited in the prairie region of Canada and northern United States. The immense number of individual salt lakes and saline wetlands in this region of North America is staggering. Estimates vary from about one million to greater than 10 million, with densities in some areas being as high as 120 lakes/km2.
Despite over a century of scientific investigation of these salt lakes, we have only in the last twenty years advanced far enough to appreciate the wide spectrum of lake types, water chemistries, and limnological processes that are operating in the modern settings. Hydrochemical data are available for about 800 of the lake brines in the region. Composition, textural, and geochemical information on the modern bottom sediments has been collected for just over 150 of these lakes. Characterization of the biological and ecological features of these lakes is based on even fewer investigations, and the stratigraphic records of only twenty basins have been examined.
The lake waters show a considerable range in ionic composition and concentration. Early investigators, concentrating on the most saline brines, emphasized a strong predominance of Na+ and SO4-2 in the lakes. It is now realized, however, that not only is there a complete spectrum of salinities from less than 1 ppt TDS to nearly 400 ppt, but also virtually every water chemistry type is represented in lakes of the region. With such a vast array of compositions, it is difficult to generalize. Nonetheless, the paucity of Cl-rich lakes makes the northern Great Plains basins somewhat unusual compared with salt lakes in many other areas of the world (e.g., Australia, western United States). Compilations of the lake water chemistries show distinct spatial trends and regional variations controlled by groundwater input, climate, and geomorphology. Short-term temporal variations in the brine composition, which can have significant effects on the composition of the modern sediments, have also been well documented in several individual basins.
From a sedimentological and mineralogical perspective, the wide range of water chemistries exhibited by the lakes leads to an unusually large diversity of modern sediment composition. Over 40 species of endogenic precipitates and authigenic minerals have been identified in the lacustrine sediments. The most common non-detrital components of the modern sediments include: calcium and calcium-magnesium carbonates (magnesian calcite, aragonite, dolomite), and sodium, magnesium, and sodium-magnesium sulfates (mirabilite, thenardite, bloedite, epsomite). Many of the basins whose brines have very high Mg/Ca ratios also have hydromagnesite, magnesite, and nesquehonite. Unlike salt lakes in many other areas of the world, halite, gypsum, and calcite are relatively rare endogenic precipitates in the Great Plains lakes. The detrital fraction of the lacustrine sediments is normally dominated by clay minerals, carbonate minerals, quartz, and feldspars.
Sediment accumulation in these salt lakes is controlled and modified by a wide variety of physical, chemical, and biological processes. Although the details of these modern sedimentary processes can be exceedingly complex and difficult to discuss in isolation, in broad terms, the processes operating in the salt lakes of the Great Plains are ultimately controlled by three basic factors or conditions of the basin: (a) basin morphology; (b) basin hydrology; and (c) water salinity and composition. Combinations of these parameters interact to control nearly all aspects of modern sedimentation in these salt lakes and give rise to four 'end member' types of modern saline lacustrine settings in the Great Plains: (a) clastics-dominated playas; (b) salt-dominated playas; (c) deep water, non-stratified lakes; and (d) deep water, "permanently" stratified lakes.
Related Articles
Is the Relationship between Body Size and Trophic Niche Position Time-Invariant in a Predatory Fish? First Stable Isotope Evidence
Nakazawa, Takefumi
Sakai, Yoichiro
Hsieh, Chih-hao
Koitabashi, Tadatoshi
Tayasu, Ichiro
Yamamura, Norio
Okuda, Noboru
PLoS ONE
Characterizing relationships between individual body size and trophic niche position is essential for understanding how population and food-web dynamics are mediated by size-dependent trophic interactions. However, whether (and how) intraspecific size-trophic relationships (i.e., trophic ontogeny pattern at the population level) vary with time remains poorly understood. Using archival specimens of a freshwater predatory fish Gymnogobius isaza (Tanaka 1916) from Lake Biwa, Japan, we assembled a long-term (>40 years) time-series of the size-dependence of trophic niche position by examining nitrogen stable isotope ratios (δ15N) of the fish specimens. The size-dependence of trophic niche position was defined as the slope of the relationship between δ15N and log body size. Our analyses showed that the slope was significantly positive in about 60% of years and null in other years, changing through time. This is the first quantitative (i.e., stable isotope) evidence of long-term variability in the size-trophic relationship in a predatory fish. This finding had implications for the fish trophic dynamics, despite that about 60% of the yearly values were not statistically different from the long-term average. We proposed hypotheses for the underlying mechanism of the time-varying size-trophic relationship.
Related Articles
High Genetic Diversity and Novelty in Eukaryotic Plankton Assemblages Inhabiting Saline Lakes in the Qaidam Basin
Wang, Jiali
Wang, Fang
Chu, Limin
Wang, Hao
Zhong, Zhiping
Liu, Zhipei
Gao, Jianyong
Duan, Hairong
PLoS ONE
Saline lakes are intriguing ecosystems harboring extremely productive microbial communities in spite of their extreme environmental conditions. We performed a comprehensive analysis of the genetic diversity (18S rRNA gene) of the planktonic microbial eukaryotes (nano- and picoeukaryotes) in six different inland saline lakes located in the Qaidam Basin. The novelty level are high, with about 11.23% of the whole dataset showing <90% identity to any previously reported sequence in GenBank. At least 4 operational taxonomic units (OTUs) in mesosaline lakes, while up to eighteen OTUs in hypersaline lakes show very low CCM and CEM scores, indicating that these sequences are highly distantly related to any existing sequence. Most of the 18S rRNA gene sequence reads obtained in investigated mesosaline lakes is closely related to Holozoa group (48.13%), whereas Stramenopiles (26.65%) and Alveolates (10.84%) are the next most common groups. Hypersaline lakes in the Qaidam Basin are also dominated by Holozoa group, accounting for 26.65% of the total number of sequence reads. Notably, Chlorophyta group are only found in high abundance in Lake Gasikule (28.00%), whereas less represented in other hypersaline lakes such as Gahai (0.50%) and Xiaochaidan (1.15%). Further analysis show that the compositions of planktonic eukaryotic assemblages are also most variable between different sampling sites in the same lake. Out of the parameters, four show significant correlation to this CCA: altitude, calcium, sodium and potassium concentrations. Overall, this study shows important gaps in the current knowledge about planktonic microbial eukaryotes inhabiting Qaidam Basin (hyper) saline water bodies. The identified diversity and novelty patterns among eukaryotic plankton assemblages in saline lake are of great importance for understanding and interpreting their ecology and evolution.
Related Articles
Effects of predation pressure and resource use on morphological divergence in omnivorous prey fish
Scharnweber, Kristin
Watanabe, Kozo
Syväranta, Jari
Wanke, Thomas
Monaghan, Michael T
Mehner, Thomas
BMC Evolutionary Biology
Body shape is one of the most variable traits of organisms and responds to a broad array of local selective forces. In freshwater fish, divergent body shapes within single species have been repeatedly observed along the littoral-pelagic axes of lakes, where the structural complexity of near shore habitats provides a more diverse set of resources compared to the open-water zones. It remains poorly understood whether similar resource-driven polymorphism occurs among lakes that vary in structural complexity and predation pressure, and whether this variation is heritable. Here, we analyzed body shape in four populations of omnivorous roach (Rutilus rutilus) inhabiting shallow lakes. We tested the relationship between body shape, gradients of resources, predation pressure, and, in a subset of two lakes, diet composition. We used genome scans of 331 polymorphic AFLP markers to test whether there was a heritable component to the observed morphological diversification.
Body shape differed among lakes and was significantly correlated to differences in predation pressure. Roach from the lake with highest predation pressure were most divergent from the average body shape of all populations, characterized by a more streamlined body and caudally inserted dorsal fins; features that facilitate predator escape. Surprisingly, diet composition was not associated with morphology. AFLP analysis revealed weak genetic differentiation among lakes and no isolation by distance (IBD). Outlier analysis detected three loci under positive selection with differing frequencies in the four populations. General linear models did not support an association of lake-specific genotypes with morphological variation.
Body shape was divergent among lakes, suggesting that processes previously reported from within single lakes may also be operating at the scale of whole lakes. We found no evidence for body shape being heritable, although sample size was small in these natural populations. Rather than habitat structure and diet, we conclude that predation had a stronger effect on the prevalence of local morphotypes. A variable morphotype facilitating the efficient uptake of a variety of spatially and temporarily scattered resources seems to be favored in these small aquatic systems.
Geometric morphometrics; AFLP; Stable isotope analysis; Gut content analysis; Shallow lakes; Predation; Outlier loci; Adaptive divergence; Rutilus rutilus; Predator induced morphological defense
Related Articles
Microbiology of Lonar Lake and other soda lakes
Paul Antony, Chakkiath
Kumaresan, Deepak
Hunger, Sindy
Drake, Harold L
Murrell, J Colin
Shouche, Yogesh S
The ISME Journal
Soda lakes are saline and alkaline ecosystems that are believed to have existed throughout the geological record of Earth. They are widely distributed across the globe, but are highly abundant in terrestrial biomes such as deserts and steppes and in geologically interesting regions such as the East African Rift valley. The unusual geochemistry of these lakes supports the growth of an impressive array of microorganisms that are of ecological and economic importance. Haloalkaliphilic Bacteria and Archaea belonging to all major trophic groups have been described from many soda lakes, including lakes with exceptionally high levels of heavy metals. Lonar Lake is a soda lake that is centered at an unusual meteorite impact structure in the Deccan basalts in India and its key physicochemical and microbiological characteristics are highlighted in this article. The occurrence of diverse functional groups of microbes, such as methanogens, methanotrophs, phototrophs, denitrifiers, sulfur oxidizers, sulfate reducers and syntrophs in soda lakes, suggests that these habitats harbor complex microbial food webs that (a) interconnect various biological cycles via redox coupling and (b) impact on the production and consumption of greenhouse gases. Soda lake microorganisms harbor several biotechnologically relevant enzymes and biomolecules (for example, cellulases, amylases, ectoine) and there is the need to augment bioprospecting efforts in soda lake environments with new integrated approaches. Importantly, some saline and alkaline lake ecosystems around the world need to be protected from anthropogenic pressures that threaten their long-term existence.
Lonar Lake; soda lakes; alkaliphiles; stable-isotope probing; microbial prospecting
Related Articles
Mercury in the Pelagic Food Web of Lake Champlain
Miller, Eric K.
Chen, Celia
Kamman, Neil
Shanley, James
Chalmers, Ann
Jackson, Brian
Taylor, Vivien
Smeltzer, Eric
Stangel, Pete
Shambaugh, Angela
Ecotoxicology (London, England)
Lake Champlain continues to experience mercury contamination resulting in public advisories to limit human consumption of top trophic level fish such as walleye. Prior research suggested that mercury levels in biota could be modified by differences in ecosystem productivity as well as mercury loadings. We investigated relationships between mercury in different trophic levels in Lake Champlain. We measured inorganic and methyl mercury in water, seston, and two size fractions of zooplankton from 13 sites representing a range of nutrient loading conditions and productivity. Biomass varied significantly across lake segments in all measured ecosystem compartments in response to significant differences in nutrient levels. Local environmental factors such as alkalinity influenced the partitioning of mercury between water and seston. Mercury incorporation into biota was influenced by the biomass and mercury content of different ecosystem strata. Pelagic fish tissue mercury was a function of fish length and the size of the mercury pool associated with large zooplankton. We used these observations to parameterize a model of mercury transfers in the Lake Champlain food web that accounts for ecosystem productivity effects. Simulations using the mercury trophic transfer model suggest that reductions of 25 to 75% in summertime dissolved eplimnetic total mercury will likely allow fish tissue mercury concentrations to drop to the target level of 0.3 µg g−1 in a 40-cm fish in all lake segments. Changes in nutrient loading and ecosystem productivity in eutrophic segments may delay any response to reduced dissolved mercury and may result in increases in fish tissue mercury.
Lake Champlain; aquatic; mercury; zooplankton; fish
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Isotopic evidence for the spatial heterogeneity of the planktonic food webs in the transition zone between river and lake ecosystems
Doi, Hideyuki
Zuykova, Elena I.
Shikano, Shuichi
Kikuchi, Eisuke
Ota, Hiroshi
Yurlova, Natalia I.
Yadrenkina, Elena
Resources and organisms in food webs are distributed patchily. The spatial structure of food webs is important and critical to understanding their overall structure. However, there is little available information about the small-scale spatial structure of food webs. We investigated the spatial structure of food webs in a lake ecosystem at the littoral transition zone between an inflowing river and a lake. We measured the carbon isotope ratios of zooplankton and particulate organic matter (POM; predominantly phytoplankton) in the littoral zone of a saline lake. Parallel changes in the δ 13C values of zooplankton and their respective POMs indicated that there is spatial heterogeneity of the food web in this study area. Lake ecosystems are usually classified at the landscape level as either pelagic or littoral habitats. However, we showed small-scale spatial heterogeneity among planktonic food webs along an environmental gradient. Stable isotope data is useful for detecting spatial heterogeneity of habitats, populations, communities, and ecosystems.
Food web; Plankton; Lake; Isotope; Spatial scale; Zooplankton; Phytoplankton; Carbon; Heterogeneity
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Willacker, James J.
Von Hippel, Frank A.
Ackerly, Kerri L.
O'Hara, Todd M.
Environmental toxicology and chemistry / SETAC
Mercury (Hg) is a widespread environmental contaminant known for the neurotoxicity of its methylated forms, especially monomethylmercury, which bioaccumulates and biomagnifies in aquatic food webs. Mercury bioaccumulation and biomagnification rates are known to vary among species utilizing different food webs (benthic vs limnetic) within and between systems. The authors assessed whether carbon and nitrogen stable isotope values and total Hg (THg) concentrations differed between sympatric benthic and limnetic ecotypes and sexes of threespine stickleback fish (Gasterosteus aculeatus) from Benka Lake, Alaska, USA. The mean THg concentration in the limnetic ecotype was significantly higher (26 mg/kg dry wt, 16.1%) than that of the benthic ecotype. Trophic position and benthic carbon percentage utilized were both important determinants of THg concentration; however, the 2 variables were of approximately equal importance in females, whereas trophic position clearly explained more of the variance than benthic carbon percentage in males. Additionally, strong sex effects (45 mg/kg dry wt, 29.4%) were observed in both ecotypes, with female fish having lower THg concentrations than males. These results indicate that trophic ecology and sex are both important determinants of Hg contamination even within a single species and lake and likely play a role in governing Hg concentrations in higher trophic levels.
Benthic carbon; Bioaccumulation; Biomagnification; Gasterosteus aculeatus; Trophic position
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Seasonal Trophic Niche Shift and Cascading Effect of a Generalist Predator Fish
Xu, Jun
Wen, Zhourui
Gong, Zhijun
Zhang, Min
Xie, Ping
Hansson, Lars-Anders
PLoS ONE
Few studies have examined how foraging niche shift of a predator over time cascade down to local prey communities. Here we examine patterns of temporal foraging niche shifts of a generalist predator (yellow catfish, Pelteobagrus fulvidraco) and the abundance of prey communities in a subtropical lake. We predicted that the nature of these interactions would have implications for patterns in diet shifts and growth of the predator. Our results show significant decreases in planktivory and benthivory from late spring to summer and autumn, whereas piscivory increased significantly from mid-summer until late autumn and also increased steadily with predator body length. The temporal dynamics in predator/prey ratios indicate that the predation pressure on zooplankton and zoobenthos decreased when the predation pressure on the prey fish and shrimps was high. Yellow catfish adjusted their foraging strategies to temporal changes in food availability, which is in agreement with optimal foraging theory. Meanwhile the decrease in planktivory and benthivory of yellow catfish enabled primary consumers, such as zooplankton and benthic invertebrates, to develop under low grazing pressure via trophic cascading effects in the local food web. Thus, yellow catfish shifts its foraging niche to intermediate consumers in the food web to benefit the energetic demand on growth and reproduction during summer, which in turn indirectly facilitate the primary consumers. In complex food webs, trophic interactions are usually expected to reduce the strength and penetrance of trophic cascades. However, our study demonstrates strong associations between foraging niche of piscivorous fish and abundance of prey. This relationship appeared to be an important factor in producing top-down effects on both benthic and planktonic food webs.
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Effect of grazers and viruses on bacterial community structure and production in two contrasting trophic lakes
Berdjeb, Lyria
Pollet, Thomas
Domaizon, Isabelle
Jacquet, Stéphan
BMC Microbiology
Over the last 30 years, extensive studies have revealed the crucial roles played by microbes in aquatic ecosystems. It has been shown that bacteria, viruses and protozoan grazers are dominant in terms of abundance and biomass. The frequent interactions between these microbiological compartments are responsible for strong trophic links from dissolved organic matter to higher trophic levels, via heterotrophic bacteria, which form the basis for the important biogeochemical roles of microbial food webs in aquatic ecosystems. To gain a better understanding of the interactions between bacteria, viruses and flagellates in lacustrine ecosystems, we investigated the effect of protistan bacterivory on bacterial abundance, production and structure [determined by 16S rRNA PCR-DGGE], and viral abundance and activity of two lakes of contrasting trophic status. Four experiments were conducted in the oligotrophic Lake Annecy and the mesotrophic Lake Bourget over two seasons (early spring vs. summer) using a fractionation approach. In situ dark vs. light incubations were performed to consider the effects of the different treatments in the presence and absence of phototrophic activity.
The presence of grazers (i.e. < 5-μm small eukaryotes) affected viral production positively in all experiments, and the stimulation of viral production (compared to the treatment with no eukaryotic predators) was more variable between lakes than between seasons, with the highest value having been recorded in the mesotrophic lake (+30%). Viral lysis and grazing activities acted additively to sustain high bacterial production in all experiments. Nevertheless, the stimulation of bacterial production was more variable between seasons than between lakes, with the highest values obtained in summer (+33.5% and +37.5% in Lakes Bourget and Annecy, respectively). The presence of both predators (nanoflagellates and viruses) did not seem to have a clear influence upon bacterial community structure according to the four experiments.
Our results highlight the importance of a synergistic effect, i.e. the positive influence of grazers on viral activities in sustaining (directly and indirectly) bacterial production and affecting composition, in both oligotrophic and mesotrophic lakes.
Lakes; microcosm; spring-summer variations; bacterial production; viral production; bacterial community structure; grazers
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Benchmarking Successional Progress in a Quantitative Food Web
Boit, Alice
Gaedke, Ursula
PLoS ONE
Central to ecology and ecosystem management, succession theory aims to mechanistically explain and predict the assembly and development of ecological communities. Yet processes at lower hierarchical levels, e.g. at the species and functional group level, are rarely mechanistically linked to the under-investigated system-level processes which drive changes in ecosystem properties and functioning and are comparable across ecosystems. As a model system for secondary succession, seasonal plankton succession during the growing season is readily observable and largely driven autogenically. We used a long-term dataset from large, deep Lake Constance comprising biomasses, auto- and heterotrophic production, food quality, functional diversity, and mass-balanced food webs of the energy and nutrient flows between functional guilds of plankton and partly fish. Extracting population- and system-level indices from this dataset, we tested current hypotheses about the directionality of successional progress which are rooted in ecosystem theory, the metabolic theory of ecology, quantitative food web theory, thermodynamics, and information theory. Our results indicate that successional progress in Lake Constance is quantifiable, passing through predictable stages. Mean body mass, functional diversity, predator-prey weight ratios, trophic positions, system residence times of carbon and nutrients, and the complexity of the energy flow patterns increased during succession. In contrast, both the mass-specific metabolic activity and the system export decreased, while the succession rate exhibited a bimodal pattern. The weighted connectance introduced here represents a suitable index for assessing the evenness and interconnectedness of energy flows during succession. Diverging from earlier predictions, ascendency and eco-exergy did not increase during succession. Linking aspects of functional diversity to metabolic theory and food web complexity, we reconcile previously disjoint bodies of ecological theory to form a complete picture of successional progress within a pelagic food web. This comprehensive synthesis may be used as a benchmark for quantifying successional progress in other ecosystems.
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Patterns of seasonal phytoplankton distribution in prairie saline lakes of the northern Great Plains (U.S.A.)
Salm, Courtney R
Saros, Jasmine E
Martin, Callie S
Erickson, Jarvis M
Saline Systems
Seasonal changes in freshwater phytoplankton communities have been extensively studied, but key drivers of phytoplankton in saline lakes are currently not well understood. Comparative lake studies of 19 prairie saline lakes in the northern Great Plains (USA) were conducted in spring and summer of 2004, with data gathered for a suite of limnological parameters. Nutrient enrichment assays for natural phytoplankton assemblages were also performed in spring and summer of 2006. Canonical correspondence analysis of 2004 data showed salinity (logCl), nitrogen, and phosphorus (N:P ratios) to be the main drivers of phytoplankton distribution in the spring, and phosphorus (C:P ratios), iron (logTFe), and nitrogen (logTN) as important factors in the summer. Despite major differences in nutrient limitation patterns (P-limitation in freshwater systems, N-limitation in saline systems), seasonal patterns of phytoplankton phyla changes in these saline lakes were similar to those of freshwater systems. Dominance shifted from diatoms in the spring to cyanobacteria in the summer. Nutrient enrichment assays (control, +Fe, +N, +P, +N+P) in 2006 indicated that nutrient limitation is generally more consistent within lakes than for individual taxa across systems, with widespread nitrogen and secondary phosphorus limitation. Understanding phytoplankton community structure provides insight into the overall ecology of saline lakes, and will assist in the future conservation and management of these valuable and climatically-sensitive systems.
Related Articles
The most acidified Austrian lake in comparison to a neutralized mining lake
Moser, Michael
Weisse, Thomas
Limnologica (Online)
This study investigated two mining lakes located in the north of Lower Austria. These lakes arose 45 years ago when open cast lignite mining ceased. The lakes are separated by a 7-m wide dam. Due to the oxidation of pyrite, both lakes have been acidified and exhibit iron, sulphate, and heavy metal concentrations several orders of magnitude higher than in circumneutral lakes. The water column of both lakes is divided into two layers by a pronounced chemocline. The smaller mining lake (AML), with pH close to of 2.6, is the most acidic lake in Austria, whereas flooding with stream water and by drainage from the surrounding fields neutralized the adjacent larger pit lake. The goal of our study was to investigate the effect of flooding on its physical, chemical and biological properties, in comparison to the pristine AML. Even relative to other extremely acidic lakes, the flora and fauna in the AML was reduced and composed of only two flagellate, one ciliate, and one rotifer species. The simplified pelagic food web in the mixolimnion consisted of heterotrophic bacteria, the mixotrophic flagellates Chlamydomonas acidophila and Ochromonas sp., the ciliate Oxytricha sp., and the rotifer Cephalodella sp. The latter two are as yet undescribed new species. The heliozoan Actinophrys sp. that may act as top predator occurred only in low abundance. The euglenid Lepocinclis buetschlii formed a stable deep chlorophyll maximum (DCM) at 7 m depth. Highest cell numbers of L. buetschlii in the DCM exceeded 108 L−1. The neutralized mining lake harboured higher plankton diversity similar to that of natural circumneutral lakes. A peak of at least 16 different phytoplankton taxa was observed during summer. The zooplankton consisted of several copepod species, daphnids and other cladocerans, and at least six different rotifer species. Several fish species occurred in the neutralized lake. Although the effect of non-permanent flooding was largely sustainable, interannual fluctuations of the pH affected the plankton community and reduced its species diversity.
Acid mining lake; Neutralization; Meromixis; Deep chlorophyll maximum; Phytoplankton; Zooplankton; Biodiversity; Langau
Related Articles
Demographic and Phenotypic Effects of Human Mediated Trophic Subsidy on a Large Australian Lizard (Varanus varius): Meal Ticket or Last Supper?
Jessop, Tim S.
Smissen, Peter
Scheelings, Franciscus
Dempster, Tim
PLoS ONE
Humans are increasingly subsidizing and altering natural food webs via changes to nutrient cycling and productivity. Where human trophic subsidies are concentrated and persistent within natural environments, their consumption could have complex consequences for wild animals through altering habitat preferences, phenotypes and fitness attributes that influence population dynamics. Human trophic subsidies conceptually create both costs and benefits for animals that receive increased calorific and altered nutritional inputs. Here, we evaluated the effects of a common terrestrial human trophic subsidies, human food refuse, on population and phenotypic (comprising morphological and physiological health indices) parameters of a large predatory lizard (∼2 m length), the lace monitor (Varanus varius), in southern Australia by comparison with individuals not receiving human trophic subsidies. At human trophic subsidies sites, lizards were significantly more abundant and their sex ratio highly male biased compared to control sites in natural forest. Human trophic subsidies recipient lizards were significantly longer, heavier and in much greater body condition. Blood parasites were significantly lower in human trophic subsidies lizards. Collectively, our results imply that human trophic subsidized sites were especially attractive to adult male lace monitors and had large phenotypic effects. However, we cannot rule out that the male-biased aggregations of large monitors at human trophic subsidized sites could lead to reductions in reproductive fitness, through mate competition and offspring survival, and through greater exposure of eggs and juveniles to predation. These possibilities could have negative population consequences. Aggregations of these large predators may also have flow on effects to surrounding food web dynamics through elevated predation levels. Given that flux of energy and nutrients into food webs is central to the regulation of populations and their communities, we advocate further studies of human trophic subsidies be undertaken to evaluate the potentially large ecological implications of this significant human environmental alteration.
Related Articles
From Bacteria to Piscivorous Fish: Estimates of Whole-Lake and Component-Specific Metabolism with an Ecosystem Approach
Cremona, Fabien
Kõiv, Toomas
Kisand, Veljo
Laas, Alo
Zingel, Priit
Agasild, Helen
Feldmann, Tõnu
Järvalt, Ain
Nõges, Peeter
Nõges, Tiina
PLoS ONE
The influence of functional group specific production and respiration patterns on a lake's metabolic balance remains poorly investigated to date compared to whole-system estimates of metabolism. We employed a summed component ecosystem approach for assessing lake-wide and functional group-specific metabolism (gross primary production (GPP) and respiration (R)) in shallow and eutrophic Lake Võrtsjärv in central Estonia during three years. Eleven functional groups were considered: piscivorous and benthivorous fish; phyto-, bacterio-, proto- and metazooplankton; benthic macroinvertebrates, bacteria and ciliates; macrophytes and their associated epiphytes. Metabolism of these groups was assessed by allometric equations coupled with daily records of temperature and hydrology of the lake and measurements of food web functional groups biomass. Results revealed that heterotrophy dominated most of the year, with a short autotrophic period observed in late spring. Most of the metabolism of the lake could be attributed to planktonic functional groups, with phytoplankton contributing the highest share (90% of GPP and 43% of R). A surge of protozooplankton and bacterioplankton populations forming the microbial loop caused the shift from auto- to heterotrophy in midsummer. Conversely, the benthic functional groups had overall a very small contribution to lake metabolism. We validated our ecosystem approach by comparing the GPP and R with those calculated from O2 measurements in the lake. Our findings are also in line with earlier productivity studies made with 14C or chlorophyll a (chl-a) based equations. Ideally, the ecosystem approach should be combined with diel O2 approach for investigating critical periods of metabolism shifts caused by dynamics in food-web processes.
Related Articles
An assessment, using stable isotopes, of the importance of allochthonous organic carbon sources to the pelagic food web in Loch Ness
Jones, R. I.
Grey, J.
Sleep, D.
Quarmby, C.
Proceedings of the Royal Society B: Biological Sciences
The natural abundance of stable isotopes (δ13C and δ1315N) was determined for components of the pelagic food web in Loch Ness, a deep oligotrophic lake in northern Scotland, and compared with values from the inflow rivers and the catchment vegetation. Phytoplankton δ13C was low compared to values reported from other lakes, possibly reflecting a high use of 13C-depleted carbon dioxide from respired organic matter before further isotopic fractionation during photosynthesis. Phytoplankton δ13C was appreciably lower than that of dissolved and particulate organic matter (DOM and POM) in the loch. The DOM and POM were evidently overwhelmingly of allochthonous origin and ultimately derived from terrestrial plant detritus. The distinctive δ13C values for phytoplankton and detritus in the loch allowed the use of food sources by grazing crustacean zooplankton to be assessed, and the contributions of phytoplankton carbon and detrital carbon to zooplankton total body carbon appeared to be about equal. Comparison of δ13C and δ15N values for zooplankton and fish allowed assessment of trophic structure in the loch. The very high dependence of the pelagic food web in Loch Ness on allochthonous organic matter inputs from the catchment may be exceptional in a large lake, but has important implications for our understanding of lake ecosystem processes as well as for lake management.
Related Articles
Influence of Climate Change and Trophic Coupling across Four Trophic Levels in the Celtic Sea
Lauria, Valentina
Attrill, Martin J.
Pinnegar, John K.
Brown, Andrew
Edwards, Martin
Votier, Stephen C.
PLoS ONE
Climate change has had profound effects upon marine ecosystems, impacting across all trophic levels from plankton to apex predators. Determining the impacts of climate change on marine ecosystems requires understanding the direct effects on all trophic levels as well as indirect effects mediated by trophic coupling. The aim of this study was to investigate the effects of climate change on the pelagic food web in the Celtic Sea, a productive shelf region in the Northeast Atlantic. Using long-term data, we examined possible direct and indirect 'bottom-up' climate effects across four trophic levels: phytoplankton, zooplankton, mid-trophic level fish and seabirds. During the period 1986–2007, although there was no temporal trend in the North Atlantic Oscillation index (NAO), the decadal mean Sea Surface Temperature (SST) in the Celtic Sea increased by 0.66±0.02°C. Despite this, there was only a weak signal of climate change in the Celtic Sea food web. Changes in plankton community structure were found, however this was not related to SST or NAO. A negative relationship occurred between herring abundance (0- and 1-group) and spring SST (0-group: p = 0.02, slope = −0.305±0.125; 1-group: p = 0.04, slope = −0.410±0.193). Seabird demographics showed complex species–specific responses. There was evidence of direct effects of spring NAO (on black-legged kittiwake population growth rate: p = 0.03, slope = 0.0314±0.014) as well as indirect bottom-up effects of lagged spring SST (on razorbill breeding success: p = 0.01, slope = −0.144±0.05). Negative relationships between breeding success and population growth rate of razorbills and common guillemots may be explained by interactions between mid-trophic level fish. Our findings show that the impacts of climate change on the Celtic Sea ecosystem is not as marked as in nearby regions (e.g. the North Sea), emphasizing the need for more research at regional scales.
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Surprising Prokaryotic and Eukaryotic Diversity, Community Structure and Biogeography of Ethiopian Soda Lakes
Lanzén, Anders
Simachew, Addis
Gessesse, Amare
Chmolowska, Dominika
Jonassen, Inge
Øvreås, Lise
PLoS ONE
Soda lakes are intriguing ecosystems harboring extremely productive microbial communities in spite of their extreme environmental conditions. This makes them valuable model systems for studying the connection between community structure and abiotic parameters such as pH and salinity. For the first time, we apply high-throughput sequencing to accurately estimate phylogenetic richness and composition in five soda lakes, located in the Ethiopian Rift Valley. The lakes were selected for their contrasting pH, salinities and stratification and several depths or spatial positions were covered in each lake. DNA was extracted and analyzed from all lakes at various depths and RNA extracted from two of the lakes, analyzed using both amplicon- and shotgun sequencing. We reveal a surprisingly high biodiversity in all of the studied lakes, similar to that of freshwater lakes. Interestingly, diversity appeared uncorrelated or positively correlated to pH and salinity, with the most "extreme" lakes showing the highest richness. Together, pH, dissolved oxygen, sodium- and potassium concentration explained approximately 30% of the compositional variation between samples. A diversity of prokaryotic and eukaryotic taxa could be identified, including several putatively involved in carbon-, sulfur- or nitrogen cycling. Key processes like methane oxidation, ammonia oxidation and 'nitrifier denitrification' were also confirmed by mRNA transcript analyses.
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Spatial patterns of mercury in biota of Adirondack, New York lakes
Yu, Xue
Driscoll, Charles T.
Montesdeoca, Mario
Evers, David
Duron, Melissa
Williams, Kate
Schoch, Nina
Kamman, Neil C.
Ecotoxicology (London, England)
We studied the spatial distribution patterns of mercury (Hg) in lake water, littoral sediments, zooplankton, crayfish, fish, and common loons in 44 lakes of the Adirondacks of New York State, USA, a region that has been characterized as a "biological Hg hotspot". Our study confirmed this pattern, finding that a substantial fraction of the lakes studied had fish and loon samples exceeding established criteria for human and wildlife health. Factors accounting for the spatial variability of Hg in lake water and biota were lake chemistry (pH, acid neutralizing capacity (ANC), percent carbon in sediments), biology (taxa presence, trophic status) and landscape characteristics (land cover class, lake elevation). Hg concentrations in zooplankton, fish and common loons were negatively associated with the lake water acid-base status (pH, ANC). Bioaccumulation factors (BAF) for methyl Hg (MeHg) increased from crayfish (mean log10 BAF = 5.7), to zooplankton (5.9), to prey fish (6.2), to larger fish (6.3), to common loons (7.2). MeHg BAF values in zooplankton, crayfish, and fish (yellow perch equivalent) all increased with increasing lake elevation. Our findings support the hypothesis that bioaccumulation of MeHg at the base of the food chain is an important controller of Hg concentrations in taxa at higher trophic levels. The characteristics of Adirondack lake-watersheds (sensitivity to acidic deposition; significant forest and wetland land cover; and low nutrient inputs) contribute to elevated Hg concentrations in aquatic biota.
Electronic supplementary material
The online version of this article (doi:10.1007/s10646-011-0717-y) contains supplementary material, which is available to authorized users.
Spatial distribution; Methylmercury; Bioaccumulation; Aquatic biota; pH; Acid neutralizing capacity
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Most news sources are funded by corporations and investors. Their goal is to drive people to advertisers while pushing the corporate agenda. NationofChange is a 501(c)3 organization funded almost 100% from its readers–you! Our only accountability is to the public. Click here to make a generous donation.
"But President Obama did just that, even letting attorneys general threaten government employees at state-run medical marijuana facilities."
Wow, really, where are or were these state run medical marijuana facilities?

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About half the Burmese pythons found in the park in the past few weeks were dead.
FORT LAUDERDALE, Fla. — Vultures circled over Everglades National Park's Anhinga Trail, where thousands of dead nonnative fish floated in the marshes.
About half the Burmese pythons found in the park in the past few weeks were dead.
Dead iguanas have dropped from trees onto patios across South Florida. And in western Miami-Dade County, three African rock pythons — powerful constrictors that can kill people — have turned up dead.
Although South Florida's warm, moist climate has nurtured a vast range of nonnative plants and animals, a cold snap last month reminded these unwanted guests they're not in Burma or Ecuador any more.
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Temperatures that dropped into the 30s killed Burmese pythons, iguanas and other marquee names in the state's invasive species zoo.
Although reports so far say the cold has not eliminated any of them, it has sharply reduced their numbers, which some say may indicate South Florida is not as welcoming to invaders as originally thought.
"Anecdotally, we might have lost maybe half of the pythons out there to the cold," said Scott Hardin, the Florida Fish and Wildlife Conservation Commission's exotic species coordinator. "Iguanas definitely. From a collection of observations from people, more than 50 percent fatality on green iguanas. Green iguanas really got hit hard. Lots of freshwater fish died; no way to estimate that."
The cold snap has played into a highly politicized debate over how to prevent nonnative species from colonizing the United States.
Reptile dealers and hobbyists strongly oppose a proposal by the U.S. Fish and Wildlife Service to ban the import of and interstate trade in Burmese pythons and several other large snakes. They say South Florida's cold snap shows these species don't threaten to spread north, as some claim, and a federal crackdown is unnecessary.
"Pythons are tropical animals," said Andrew Wyatt, president of the United States Association of Reptile Keepers. "When temperatures fall below a certain level, they are unable to survive. It reinforces the idea that the pythons can't exist more than a short period of time north of Lake Okeechobee. Even the pythons in the Everglades are dying during the cold snap."
Wyatt said scientists are downplaying the effect of cold weather on the pythons because that would undermine their ability to win grants to study a problem that has received international publicity.


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These Chocolate Chip Cookie Dough Bites are delicious and addicting. Beware!
Who doesn't love raw cookie dough? Something about the chewy, moist texture and pronounced flavors that make the dough too tempting … mmm.
I'm bringing the Chocolate Chip Cookie Dough Bites to an upcoming Holiday Cookie Exchange and I couldn't be more excited. But I wanted to share them with you too because they're not only delicious, they're easy to make {no-bake} and use natural ingredients. What's not to love?
Hope you enjoy them!


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Rainwater - Safe and Sustainable Water SupplyRainwater Harvesting on Dirty RoofsMajor Benefits of Using Harvested Rainwater
The most valuable natural resource is water and most people are aware of the limited supply and importance of water especially in dry continents such as Australia. Rainwater harvesting is a three step process involving the collection of rainwater from surfaces such as roofs; the storage of rainwater and the distribution of rainwater for indoor or outdoor use.
Rainwater is an economical, safe and sustainable source of quality water when it is captured and stored in a correct manner.
Compared with water supplied through mains, rainwater can be considered to be safer since water supplied from mains is typically stored in dams and treated with chemicals to eliminate bacteria. This water is then pumped through a network of pipes which may contain contaminants such as rust.
A number of first flush devices or rain diverters are available. These devices divert or flush off the first flow of water of a storm. Any dirt, contaminants or bacteria on the roofs of buildings that has built up before the rain can be prevented from entering the storage tank.
By using rainwater, a number of significant economic, social and environmental benefits can be accomplished.
By using rainwater harvesting systems to capture rainwater, the reliance on water storage dams and systems can be significantly reduced. This also places less pressure on water storage systems and can possibly lessen the need to increase the water storage infrastructure. Collecting and using harvested rainwater can also considerably decrease the size of your water bills.
Source: AZoCleantechLast update 6th April 2008
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The Gateway Technical College District is governed by a nine-member board of trustees representing the communities served by the three-county district, which is comprised of two employer members, two employee members, one elected official, one school district administrator, and three additional members. Members are appointed by the chairpersons of the Kenosha, Racine, and Walworth County Boards of Supervisors, and serve staggered three-year terms.
View the Gateway Technical College District Board Governance Policies.
Contact the board at 262-564-3614 or by email (below).
Board Members
Gary Olsen
William Duncan
Vice Chairperson
Susan Greenfield
Ronald J. Frederick
Ram Bhatia
Bethany Ormseth
R. Scott Pierce
Roger Zacharias
Pamela Zenner-Richards
About the Board Members
Gary Olsen
Gary Olsen is the Director of Buildings and Grounds for the Burlington Area School District and serves as Safety Coordinator, positions which he has held for 34 years. He oversees a department of five building engineers and 30 custodians. His department is responsible for the care and maintenance of 9 buildings that included approximately 741,000 square feet of space and 305 acres of land. He has developed a Roadmap for Maintenance Excellence to support the district's Roadmap for Instructional Excellence. Gary graduated from Salem High School and holds a First Class License and certification for Boiler and Power Plant Operation from the American Society of Power Engineers and Niulpe, which he earned from Gateway in 1987. In addition, he earned ICS 100, 200, 300, and 700 Certifications from the FEMA Emergency Management Institute National Incident Management System (NIMS). He has served on the Gateway District Board since 2010 representing the Employer category for Walworth County.
William Duncan
Vice Chairperson
William B. Duncan, Ed.D is presently the President of Duncan Mediation & Consulting Services, LLC. He recently retired as Senior Vice President of Aurora University and served as the overall administrator for the George Williams College in Williams Bay, WI. He holds a Bachelor of Arts degree from the University of California, Davis; a Master of Science degree from George Williams College; and a doctorate in Adult Continuing Education from Northern Illinois University. He holds an honorary doctorate in Humane Letters from Aurora University. He is in his second term as an elected Trustee of the Village of Williams Bay. He serves on the board of the Williams Bay Business Association and other local boards and commissions. He has a strong interest in adult learning and technical education. Dr. Duncan has served the Gateway Technical District Board since 2013 representing the Additional Member category for Walworth County.
Susan Greenfield
Susan Greenfield is retired, most recently working as the executive director of the Root-Pike Watershed Initiative from 2007-14. She has been a member of the Gateway Technical College Board of Trustees since 2013. Before Root-Pike, Susan was a consultant in land planning, conservation and restoration and a former chairwoman of the Town of Caledonia, where she served for eight years on the town board. Prior to serving as an elected official, Susan was the principal of Susan Greenfield Communications and employed as the communications manager for the Aspin Procurement Institute. Susan is considered a local leader in conservation land use planning and watershed planning. In 2004, she was named Wisconsin's Policy Maker of the Year by Gathering Waters and Woman of Distinction for the Environment by YWCA in 2008. Susan earned her bachelor's degree with honors from UW-Parkside in 1980, and her master's degree in mass communication from Marquette University in 1997.
Ronald J. Frederick
Ronald J. Frederick is retired, most recently working as executive director and project director for Senior Community Services of Southeastern Wisconsin, Inc. He worked for Senior Community Services from 1996-2007. He currently serves as a member of the Kenosha County Board of Supervisors – a position he has held from 2010 – representing District 11. Ronald served as a Gateway Technical College Board of Trustees member three separate times, 1983-87, 1993-99, and then 2006-09. He was the board chairperson 1995-96. Ronald served on many labor organization in various positions including Steelworkers Union Local 9322 from 1956-76 as president, vice president, chief steward and on its executive board. He also served as president of the Kenosha AFL-CIO Council 1962-1972 and 2003-13. Ronald's community service is vast, including serving on the Southeastern Wisconsin Workforce Development Board 2001-present, Kenosha County Workforce Development 2003-present and on the City of Kenosha Police and Fire Commission, 2008-13. Ronald is a veteran, serving in the Air Force 1952-56.
Ram Bhatia
Ram Bhatia is an accomplished senior executive with over 25 years of experience in the electrical engineering industry. Ram has worked at both Fortune 500 international companies as well as small /local companies, where he has managed departments as well as large turn key projects. An electrical engineer holding two Masters Degrees in engineering and an MBA from UW-Parkside, Ram is particularly effective in initiating and implementing strategies and programs that result in increased profitability, revenue growth, increased market share and costs containment. He is also a Fellow of the Institute of Electrical and Electronics Engineers (IEEE) and serves as the Director for the Milwaukee Section of IEEE and was past Section Chair. Ram is very passionate about technical education that serves the local industry, and influences the economic well-being of the community. He has served on the Gateway District Board since 2005 representing the Additional Member category for Racine County.
Bethany Ormseth
Bethany Ormseth, Ed.D., is currently the Assistant Superintendent of Secondary School Leadership for the Kenosha Unified School District. Bethany taught high school science, served as a middle school principal and most recently was the principal at Indian Trail High School and Academy. She holds a Bachelors of Arts degree from Lawrence University, a Masters of Science Degree in Educational Leadership from the University of Wisconsin at Milwaukee and received her Doctorate in 2010 from Cardinal Stritch University Dr. Ormseth has served on the Gateway Board since July 2013 representing the Employer Member category for Kenosha County.
R. Scott Pierce
R. Scott Pierce, Ed.D is presently the District Administrator for Central High School District of Westosha, a position which he has held since 2008. His background in higher education started 1983 as an Assistant Principal at Platteville High School, Platteville, WI. His career trajectory paved the path to various roles from Associate Principal to Superintendent of Schools leveraging his expertise in higher education thus ultimately leading to his role as District Administrator. He received his Bachelor of Arts with an emphasis on Music Education from Carthage College, holds a Master of Education Professional Development with an emphasis on Educational Administration from the University of Wisconsin – Whitewater, an Education Specialist in Educational Administration from the University of Wisconsin - Milwaukee and a Doctorate of Education from Cardinal Stritch University. Dr. Pierce has served on various city, county and state level boards and has served the Gateway Technical District Board since 2009 representing the School District Administrator category for Kenosha County.
Roger Zacharias
Roger Zacharias is currently a Business Representative for the Chicago Regional Council of Carpenters, a position he has held for eleven years. Prior to that, he was employed by many of the local contractors for 15 years. He serves as Vice President of Carpenters Local 161. He completed his Carpenters apprenticeship in October 1990 at the Kenosha Campus. Roger has served on the Gateway District Board since 2004 and representing the Employee category for Kenosha County.
Pamela Zenner-Richards
Pamela Zenner-Richards is a semi-retired administrator with 20+ year's experience in operations management in for-profit industries and non-profit industries. Accomplished in development of new programs and leading change. Expertise includes: manufacturing, human resources, staff management, education and training, sales and marketing, government services, economic development and customer relations. She is a strong supporter of technical education and has seen its value first hand in her life and work. Pam has served on the Gateway District Board since 2000 and representing the Elected Official category for Racine County.


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We chose this place because it was walking distance from our hotel. We were a little weary once we walked in on a Saturday around 6pm and found it nearly empty. We were promptly seated, and quickly greeted by our waitress. I think her name was Joan...she was FANTASTIC.
I had the cannelloni special, which was huge portion and pretty tasty. My wife had the fettucine alfredo, and she says it was the best she's ever had. I tasted hers as well, it was amazing. The meals came with salad, we chose Caesar. The salad was good for the most part, but the dressing was very unusual. Homemade bread was also provided, with dipping oil.
Prices were reasonable, and as I already said, the service was top notch. Will definitely visit again next time we are in the area.
Today's Deal: 50% Off Tuscano RestaurantTuscano Restaurant
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What a little gem stuck in an out of the way place. Find it, you won't be sorry. The sauce is truly as good as I have ever had (Philly, NYC Little Italy, Chicago, Pittsburgh....) Staff is very good, menu is full of homemade pastas. I have been there 6 times so far and can't wait to go back.
What's better than a pound of cheese ravioli? Two pounds. You can never really have enough cheese—but hey, top it off with some parmesan for good luck.
At Tuscano Restaurant eat your body weight in tortellini, lasagna, spaghetti, fettuccini, chicken parmigiana, veal, seafood and more molto bene entrees.
The whole family can enjoy this casual Italian dining experience—Tuscano's features a delectable kid's menu including Leonardos Pizza and Donatellos Chicken Fingers and Fries.
Save your appetite for this dinner—trust us, once you start twirling, you won't be able to stop.
Veal Alla Franchese
Veal beer battered in lemon garlic wine sauce with fresh mushrooms—might as well order three dishes of it.
Potato Gnocchi
Served in creamy tomato sauce.
The Deal
- Just $15 gets you $30 to spend on Italian cuisine at Tuscano Restaurant
- We like that marinara mustache you're rockin'.
Fine Print
Promotional value expires 10/15/2013; Not valid for cash back; Not valid for use with other offers or promotions; Does not cover tax or gratuity; Dine in only; Cannot be used towards alcohol; Must be used in one visit
About the Merchant Tuscano Restaurant
Tuscano Restaurant
421 Friendship Road
Harrisburg, Pennsylvania, 17111 Phone: 717.561.5151 Get Directions
Harrisburg, Pennsylvania, 17111 Phone: 717.561.5151 Get Directions


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|Número de publicación
|Tipo de publicación
|Número de solicitud
|Fecha de publicación
|8 Jun 2004
|Fecha de presentación
|2 Jul 2003
|Fecha de prioridad
|2 Jul 2003
|También publicado como
|Número de publicación
|Kenneth J. Hicks, David L. Henderson, Jozef Boros
|Cesionario original
|Rheem Manufacturing Company
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|BiBTeX, EndNote, RefMan
|Citas de patentes (23), Citada por (16), Clasificaciones (6), Eventos legales (5)
|Enlaces externos: USPTO, Cesión de USPTO, Espacenet
The present invention generally relates to water flow control apparatus and, in illustrated embodiments thereof, more particularly relates to specially designed water heater convective heat trap constructions.
Water heaters of both the fuel-fired and electrically heated types typically have a tank portion in which pressurized, heated water is stored for on-demand delivery to various types of hot water-utilizing plumbing fixtures such as, for example, sinks, bath tubs and dishwashers. During standby periods in which discharge of stored hot water from the tank is not required, it is desirable to substantially reduce heat loss from the stored hot water to cooler areas outside the tank. For this reason it is customary practice to externally insulate the tank.
While this technique is effective in reducing undesirable heat loss from the tank body, stored water heat may also be lost by thermal convection flow of heated water from the tank through its cold water inlet and hot water outlet openings to piping connected thereto. In order to minimize this convective heat loss, various convective heat trap devices have been previously proposed for connection to the tank at or adjacent these inlet and outlet openings. These heat trap devices are basically check valve-type structures which freely permit water to flow through the tank inlet and outlet in operational directions during water supply periods, but substantially inhibit convective water outflow through the inlet and outlet during non-demand storage periods of the water heater.
One common type of convective heat trap utilizes a movable ball to block or impede undesirable convective water flow through its associated water inlet or outlet opening in the tank. While this ball type of heat trap typically eliminates or at least substantially reduces outward convective water flow, it also is prone to create undesirable noise (namely, "rattling") during its operation. This has led to many complaints from water heater purchasers over the Years and corresponding repair or replacement costs for water heater manufacturers.
In response to this well-known problem typically associated with ball-type heat traps various "flapper" type heat trap constructions have been previously proposed as alternatives to movable ball-type heat traps. In this design, a flexible blocking member (or "flapper") is appropriately positioned in each path of potential convective outflow currents of water from the tank (i.e., at or adjacent the cold water inlet and hot water outlet of the tank) and serves as a barrier to undesirable convective outflows of heated tank water during non-demand periods of the water heater. However, when one or more of the plumbing fixtures connected to the water heater is operated to draw hot water from the tank, the flappers resiliently deflect to freely permit cold water supply to the tank and hot water discharge from the tank. Because of the resilient nature of the flappers their operation is typically silent.
However, compared to ball type heat traps flapper type convective heat traps present their own types of problems, limitations and disadvantages including potentially higher cost and greater complexity, installation difficulties, additional shipping volume and less than optimal reductions in convective heat loss from their associated water heater. A need accordingly exists for improved water heater convective heat trap designs. it is to this need that the present invention is directed.
In carrying out principles of the present invention, in accordance with an illustrated embodiment thereof, a water heater is provided which includes a tank adapted to store a quantity of water and having water inlet and outlet openings; heating apparatus for heating water stored within the tank; and first and second specially designed heat traps respectively associated with the water inlet and outlet openings and operative to inhibit convective water outflows therethrough.
Each heat trap includes a tubular body extending along an axis; and first and second axially spaced apart resilient flapper structures carried by the body and having axially deflectable portions transversely extending across the interior of the body. Preferably, the deflectable flapper structure portions in each heat trap body are axially deflectable about circumferentially offset hinge locations adjacent the interior side surface of the body. Representatively, the hinge locations are circumferentially offset from one another by about 180 degrees. Additionally, when the resilient flapper portions are in undeflected orientations within their associated heat trap body they preferably define circumferentially extending gaps with the interior side surface of the body.
In an illustrated embodiment of the heat traps, each tubular body representatively has an outwardly projecting integral end flange with a noncircular driving recess formed in an outer side thereof. Axially spaced exterior annular grooves are formed in the body side wall, with circumferentially offset slots extending radially through the body at such grooves. Each resilient flapper member has a circular outer ring portion received in one of the grooves, and a generally circular interior portion received within the interior of the body and connected to the ring by a hinge tab portion extending outwardly through the associated slot and being formed integrally with the outer ring.
The heat trap at the cold water inlet of the tank is coaxially received in an upper end portion of a cold water inlet dip tube extending downwardly into the interior of the tank. Alternatively, the tubular body of the heat trap at the cold water inlet of the tank is eliminated, and the flapper members are incorporated directly into the dip tube to form a combination dip tube/heat trap structure.
Representatively, tubular connection spuds are externally secured to the tank over its cold water inlet and hot water outlet openings, and dip cup members extend downwardly through these openings. Tubular seal members circumscribe the hot water side heat trap body and the dip tube and sealingly engage the associated spuds and dip cups. Illustratively, these external seal structures are separate elements, but may alternately be formed integrally with the internal flapper portions. The non circular driving recesses in the flange portions of the heat traps are used to thread the flange edges into threaded interior portions of the connection spuds.
The specially designed neat traps substantially inhibit undesirable convective water flow outwardly through the cold water and hot water tank openings, with the circumferentially offset, axially spaced interior flapper portions forcing tank water to take a generally serpentine path outwardly through the traps. The heat traps operate very quietly, are of a simple construction, are easy to install, are inexpensive to manufacture, and operate in a reliable manner to materially reduce undesirable convective outflow of water from the tank during standby periods of the water heater.
FIG. 1 is a simplified, somewhat schematic cross-sectional view through an upper end portion of a representative water heater in which specially designed convective heat traps embodying principles of the present invention have been installed;
FIG. 2 is an enlarged scale detail view of the dashed circle area "2" in FIG. 1 and illustrates one of the heat traps installed at the hot water outlet of the water heater;
FIG. 3 is a perspective view of a tubular body portion of the FIG. 1 heat trap with associated flapper members removed therefrom;
FIG. 4 is a top end view of the heat trap with the flapper members operatively installed therein;
FIG. 5 is a side view of one of the flapper members removed from the heat trap;
FIG. 6 is an enlarged scale detail view of the dashed circle area "6" in FIG. 1 and illustrates another heat trap operatively installed in a dip tube at the cold water inlet opening of the water heater;
FIG. 7 is a simplified, somewhat schematic cross-sectional view through a dip tube in which an axially spaced pair of flapper members are directly installed; and
FIG. 8 is a simplified, somewhat schematic cross-sectional view through an alternate embodiment of the FIG. 7 dip tube structure incorporating therein a combination tubular exterior seal element and interior flapper member which formed integrally with the seal element.
Cross-sectionally depicted in somewhat schematic form in FIG. 1 is a top end portion of a representative water heater 10 in which specially designed convective heat traps 12 a, 12 b embodying principles of the present invention are incorporated. Water heater 10 is representatively an electric water heater, but could alternatively be a fuel-fired water heater without departing from principles of the present invention, and includes a water storage tank 14 surrounded by an outer insulated jacket structure 16 of conventional construction. Pressurized water 18 stored in the tank 14 is heated by one or more immersion type electrical resistance heating elements 20 extending through the water 18 in the tank 14.
With reference now to FIGS. 1, 2 and 6, the upper end 21 of the outer wall portion of the jacket structure 16 has formed therein a hot water outlet opening 22, a cold water inlet opening 24, and a temperature and pressure relief opening 26. Formed through the top end 27 of the tank 14, and respectively underlying the openings 22 and 24, are a hot water outlet opening 28 and a cold water inlet opening 30. A temperature and pressure relief opening (not shown) is also formed through the upper tank end wall and underlies the jacket opening 26.
As best illustrated in FIGS. 2 and 6, tubular metal pipe connection spuds 32 have lower ends welded to the upper tank end wall 27, over the hot and cold water openings 28,30 therein, and have threaded upper interior end portions 34 thereon into which hot and cold water pipes 36,38 (shown in phantom in FIGS. 2 and 6) may be threaded. Coaxially supported at the hot and cold water tank openings 28,30, and projecting downwardly therefrom into the interior of the tank 14, are annular support cup members 40.
Referring now to FIGS. 2-6, the heat traps 12 a, 12 b are identical to one another with each heat trap having a tubular body 42, representatively of a molded plastic construction, and a pair of circular flapper members 44 having flat configurations and formed from a resiliently deflectable material, representatively a suitable elastomeric material.
Tubular body 42 has an outwardly projecting circular top end flange 46 (see FIGS. 3 and 4) with a hexagonally shaped driving recess 48 extending downwardly through its top side and communicating with the interior of the body 42. on its exterior side surface the tubular body has two axially spaced apart annular grooves 50. Each groove 50 has a radial slot 52 (see FIG. 3) extending inwardly therethrough to the interior of the body 42. Preferably, the slots 52 are circumferentially offset from one another, illustratively by 180 degrees.
As best illustrated in FIG. 5, each flapper member 44 has a partially circular slot 54 formed therein adjacent its periphery. Slot 54 defines in the flapper member 44 a generally circular interior portion 56 joined to a circular outer rim portion 58 by a pivot tab section or hinge section 60. Each of the heat traps 12 a, 12 b is assembled by inserting the interior portions 56 of two flapper members 44 inwardly through the body slots 52 and then snapping the two rim portions 58 into the two outer side surface grooves 50 of the tubular heat trap body 42. As cross-sectionally illustrated in FIGS. 2 and 6, in each of the heat traps 12 a, 12 b this positions the interior portions 56 of its two flapper members 44 within axially spaced apart interior portions of the tubular body 42, with the two interior flapper member portions 56 being hinged at locations within the body 42 circumferentially spaced apart from one another by 180 degrees.
To install the heat trap 12 a at the tank hot water outlet opening 28 (see FIG. 2), an annular resilient seal member 62 is first inserted downwardly through the spud 32 so that the inserted seal member 62 bears against the lower end of the support cup member 40. Next, the heat trap 12 a is screwed into the spud 32 using a suitable tool inserted into the hex recess area 48 of the heat trap body 42 to rotationally drive the body 42 in a manner causing the outer edge of its flange portion 46 to thread into the threaded interior portion 34 of the spud 32. When the heat trap 12 a is installed as shown in FIG. 2, the lower end of the heat trap body 42 projects downwardly through the open lower end of the support cup member 40, with the upper and lower ends of the seal member 62 respectively and sealingly engaging the bottom side surface of the flange 46 and the lower end of the support cup member 40 as shown in FIG. 2. The pipe 36 may then be threaded into the spud 32 as shown.
To install the heat trap 12 b at the tank cold water inlet opening 30 (see FIG. 6), an annular resilient seal member 62 is first installed in the spud 32 as previously described, and an elongated tubular dip tube member 64 is inserted downwardly through the seal member 62 until the dip tube 64 extends downwardly through the open lower end of the support cup member 40 into the interior of the tank 14, and an upper end flange 66 on the dip tube 64 engages the top end of the installed seal member 62. Next, the heat trap 12 b is threaded downwardly into the spud 32 as previously described until the heat trap enters the interior of a top end portion of the dip tube 64 and the heat trap body flange 46 downwardly engages the dip tube flange 66 as shown in FIG. 6. Finally, the pipe 38 is threaded into the spud 32.
During standby periods of the water heater 10, the interior portions 56 of the heat trap flapper members 44 substantially inhibit upward convective flows of heated water 18 upwardly through their associated heat traps 12 a, 12 b. Specifically, at the tank hot water outlet opening 28 (See FIG. 2), during standby periods of the water heater 10 convective flow 18 a of heated water 18 is forced to traverse a generally serpentine path past the oppositely facing outer edges of the oppositely hinged flapper member interior portions 56. However, during drawdown periods of the water heater 10 (i.e., when cold water is entering the tank 14 and hot water is being discharged therefrom), the outgoing hot water 18 upwardly traversing the pipe 36 simply bends the flapper member interior portions 56 upwardly so that they provide only insignificant resistance to hot water outflow through the heat trap 12 a.
In a similar fashion, at the tank cold water inlet opening 30 (see FIG. 6), during standby periods of the water heater 10 convective flow 18 a of heated water 18 is forced to traverse a generally serpentine path past the oppositely facing outer edges of the oppositely hinged flapper member interior portions 56. However, during drawdown periods of the water heater 10 the incoming cold water downwardly traversing the pipe 38 simply bends the flapper member interior portions 56 downwardly so that they provide only insignificant resistance to cold water inflow through the heat trap 12 b.
As previously described, at the cold water inlet portion of the representative water heater 10 separate heat trap and dip tube structures are utilized. in FIG. 7 an alternate combination dip tub/heat trap structure 70 is schematically illustrated in cross-section and includes a cold water inlet dip tube 72 (only an upper end portion of which is shown) and a convective heat trap integrally formed therewith. The integral heat trap is defined by two of the previously described circular flapper members 40, the interior portions 56 of which are inserted through longitudinally spaced apart, circumferentially opposite slots 74 formed through the tubular body of the dip tube 72. The circular outer rim portions 58 of the flapper members 44 may be snapped into suitable exterior annular grooves formed in the body of the dip tube 72. AS illustrated, the interior portions 56 of the two axially spaced flapper members 44 are pivoted on opposite internal sides of the dip tube 72 to form the generally serpentined outlet path for upwardly directed convective heated water currents previously described herein.
Schematically depicted in cross-sectional form in FIG. 8 is a further alternate heat trap embodiment 76 which also embodies principles of the present invention and includes a tubular body 78 (which could be a dip tube) having attached thereto a combination seal/flapper structure defined by an annular resilient seal member 80 outwardly circumscribing the body 78 and a circular flapper member 82 formed integrally with the seal member 80 and extending transversely into the interior Of the tubular body 78 through a suitable side wall slot 84 in the body 78 and being connected to the seal member 80 by a hinge tab portion 86. To provide the heat trap 76 with axially spaced apart flapper structures within the tube 78, another combination seal/flapper structure 80,82 can be secured to the tube 78 below the illustrated seal/flapper structure 80,82. As will be appreciated, the heat trap 76 may be substituted for any of the previously described heat trap structures if desired, with the integral seal member 80 replacing the separate external seal structures.
The foregoing detailed description is to be clearly understood as being given by way of Illustration and example only, the spirit and scope of the present invention being limited solely by the appended claims.
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|Clasificación de EE.UU.
|122/14.31, 137/855
|Clasificación internacional
|Clasificación cooperativa
|Clasificación europea
|14 Oct 2003
Owner name: RHEEN MANUFACTURING COMPANY, NEW YORK
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:HICKS, KENNETH J.;HENDERSON, DAVID L.;BOROS, JOZEF;REEL/FRAME:014590/0431;SIGNING DATES FROM 20030819 TO 20030820
|10 Dic 2007
|Fee payment
Year of fee payment: 4
|17 Dic 2007
|Maintenance fee reminder mailed
|8 Dic 2011
|Fee payment
Year of fee payment: 8
|8 Dic 2015
|Fee payment
Year of fee payment: 12


text:
Acting sheepish
Wed, 01/20/2016 - 7:19pm News Staff
This herd of big horn sheep was spotted this past Sunday peering
An autopsy of human remains found west of Gunnison has been scheduled for Tuesday.
by Chris Rourke
by Will Shoemaker
by Will Shoemaker
Western State Colorado University sophomore Travis Bradford wrestles to a 15-8 win over University of Central Oklahoma's Daniel Carillo during the Tracy Borah Duals this past Saturday in Gunnison.
by Bobby Reyes
by Bobby Reyes
Will Shoemaker
Times Editor
218 N. Wisconsin Street
Gunnison, CO 81230
Phone: 970-641-1414


text:
When the Wind Blows
When the Wind Blows
Vision, Mass Market Paperback, 9780446607650, 448pp.
Publication Date: October 1, 1999
Frannie O'Neill is a talented Colorado veterinarian haunted by her husband's murder. But the course of her life is about to change again. After another bizarre killing, Kit Harrison, a troubled and unconventional FBI agent, arrives on her doorstep. And late one night Frannie stumbles upon a strange, astonishing phenomenon. Her name is Max. Only eleven years old, she will lead Frannie and Kit to uncover one of the most diabolical and inhuman plots of modern science.
James Patterson has had more New York Times bestsellers than any other writer, ever, according to Guinness World Records. Since his first novel won the Edgar Award in 1977 James Patterson's books have sold more than 240 million copies. He is the author of the Alex Cross novels, the most popular detective series of the past twenty-five years, including Kiss the Girls and Along Came a Spider. Mr. Patterson also writes the bestselling Women's Murder Club novels, set in San Francisco, and the top-selling New York detective series of all time, featuring Detective Michael Bennett. He writes full-time and lives in Florida with his family.


text:
Everyone on the liberal left laughed it up when prophetic conservatives on fine stations such as Fox News, with independent journalists such as the graceful Ann Coulter or Michell Cmalkin as well, questioned the character of Barack Hussein Obama. Could this man be trusted? Could his name more accurately be that of our great enemy, Osama Bin Laden? Well now signs are starting to point to yes and the likes of Jon Stewart and other liberal miscreants don't find it […]
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text: It's Japan, so there were obviously going to be a lot of RPGs at this event; those meant for the western market and otherwise. The Final Fantasy XIII series in particular is very polarizing in the west. There is very little middle ground --people either enjoy the series or hate it. Lightning Returns brought a lot of freshness to the franchise, and RPG in general, from our experience with the demo. The dead time from the ATB system RPGs employ has been eliminated with a creative use of the dress sphere system from FFX-2, making the Cloud costume available for Lightning have a gameplay purpose other than cosmetics and fan service. This new combat system it is employing also added lots of depth and strategy to the series, and was more enjoyable to play than previous titles.


text:
I've been looking for black and white conversion which has interesting tones and just found this preset, and the good thing is it's free. Thanks to Pretty Presets, awesome preset!. Download it here from Pretty Presets And here's the sample picture, before and after.
Monthly Archives: February 2011
8 February is his birthday, and special for today only: Kyan can eat anything he wants and buy any toys he wants :p