the majority of fresh water on our planet comes from lakes.
19. the majority of fresh water on our planet comes from?
lakes
species of fish living in cold or cool water can see a reduction in population of up to 50% in the majority of u.s. fresh water streams, according to most climate change models. the increase in metabolic demands due to higher water temperatures, in combination with decreasing amounts of food will be the main contributors to their decline. additionally, many fish species (such as salmon) utilize seasonal water levels of streams as a means of reproducing, typically breeding when water flow is high and migrating to the ocean after spawning. because snowfall is expected to be reduced due to climate change, water runoff is expected to decrease which leads to lower flowing streams, effecting the spawning of millions of salmon. to add to this, rising seas will begin to flood coastal river systems, converting them from fresh water habitats to saline environments where indigenous species will likely perish. in southeast alaska, the sea rises by 3.96 cm/year, redepositing sediment in various river channels and bringing salt water inland. this rise in sea level not only contaminates streams and rivers with saline water, but also the reservoirs they are connected to, where species such as sockeye salmon live. although this species of salmon can survive in both salt and fresh water, the loss of a body of fresh water stops them from reproducing in the spring, as the spawning process requires fresh water. undoubtedly, the loss of fresh water systems of lakes and rivers in alaska will result in the imminent demise of the state's once-abundant population of salmon.
climate change and ecosystems
section::::impacts.:fresh water.:combined impact.





























in general, as the planet warms, the amount of fresh water bodies across the planet decreases, as evaporation rates increase, rain patterns become more sporadic , and watershed patterns become fragmented, resulting in less cyclical water flow in river and stream systems. this disruption to fresh water cycles disrupts the feeding, mating, and migration patterns of organisms reliant on fresh water ecosystems. additionally, the encroachment of saline water into fresh water river systems endangers indigenous species which can only survive in fresh water.





























section::::impacts.:ecological productivity.
climate change and ecosystems