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- Fecha de creación febrero 2, 2021
Through litter decomposition an enormous amount of carbon is emitted to the atmosphere. Numerous large-scale decomposition experiments have been conducted focusing on this fundamental soil process in order to understand the controls on the terrestrial carbon transfer to the atmosphere. However, previous studies were mostly based on site-specific litter and methodologies, adding major uncertainty to syntheses, comparisons and meta-analysis across different experiments and sites. In the TeaComposition initiative, the potential litter decomposition is investigated by using standardized substrates (Rooibos and Green tea) for comparison of litter mass loss in 336 sites (ranging from −9 to +26 °C MAT and from 60 to 3113 mm MAP) across different ecosystems. In this study we tested the effect of climate (temperature and moisture), litter type and land-use on early stage decomposition (3 months) across nine biomes. We show that litter quality was the predominant controlling factor in early stage litter decomposition, which explained about 65% of the variability in litter decomposition at a global scale. The effect of climate, on the other hand, was not litter specific and explained <0.5% of the variation for Green tea and 5% for Rooibos tea, and was of significance only under unfavorable decomposition conditions (i.e. xeric versus mesic environments). When the data were aggregated at the biome scale, climate played a significant role in decomposition of both litter types (explaining 64% of the variation for Green tea and 72% for Rooibos tea). No significant effect of land-use on early stage litter decomposition was noted within the temperate biome. Our results indicate that multiple drivers are affecting early stage litter mass loss with litter quality being dominant. In order to be able to quantify the relative importance of the different drivers over time, long-term studies combined with experimental trials are needed.
"Kutoka kwa ""Mafunzo ya Maji"" (Tamaño del Archivo, 24 Feb. 2021), ni muhimu kutambua kwamba, kwa sababu ya uharibifu wa maji, kiasi kikubwa cha kaboni hutolewa angani." Majaribio mengi ya kuharibika kwa kiwango kikubwa yamefanywa kwa kuzingatia mchakato huu wa msingi wa udongo ili kuelewa udhibiti wa uhamisho wa kaboni ya ardhi kwenye anga. Hata hivyo, masomo ya awali yalikuwa hasa msingi wa tovuti maalum litter na mbinu, kuongeza kutokuwa na uhakika mkubwa kwa syntheses, kulinganisha na meta-uchambuzi katika majaribio tofauti na maeneo. Katika mpango wa TeaComposition, uwezekano wa uharibifu wa uchafu unachunguzwa kwa kutumia substrate za kawaida (Rooibos na Green Tea) kwa kulinganisha upotezaji wa wingi wa uchafu katika maeneo 336 (kuanzia -9 hadi +26 ° C (MAT) na kutoka 60 hadi 3113 mm (MAP) katika mazingira tofauti. Katika utafiti huu, tulijaribu athari za hali ya hewa (joto na unyevu), aina ya litter na matumizi ya ardhi kwenye hatua ya mapema ya uharibifu (miezi mitatu) katika biomes tisa. "Tunaonyesha kwamba ubora wa taka ulikuwa sababu kuu ya kudhibiti katika hatua ya mapema ya uharibifu wa taka, ambayo ilielezea karibu 65% ya kutofautiana kwa uharibifu wa taka kwa kiwango cha kimataifa. """ Kwa upande mwingine, athari ya hali ya hewa haikuwa maalum kwa mchanga na ilielezea <0.5% ya tofauti kwa chai ya kijani na 5% kwa chai ya rooibos, na ilikuwa muhimu tu chini ya hali mbaya za uharibifu. X-ray na mesh environments Kwa mfano, katika hali ya hewa ya hewa, ambayo ni muhimu kwa ajili ya uharibifu wa aina zote mbili za mchanga (kuelezea 64% ya tofauti kwa ajili ya chai ya kijani na 72% kwa ajili ya chai ya rooibos). Hakuna athari kubwa ya matumizi ya ardhi juu ya hatua ya mapema ya uharibifu wa litter ilibainishwa ndani ya biome ya hali ya wastani. Matokeo yetu yanaonyesha kwamba madereva mbalimbali ni kuathiri hatua ya mapema litter wingi kupoteza na ubora litter kuwa kutawala. Ili kuweza kupima umuhimu wa jamaa wa madereva tofauti kwa muda, masomo ya muda mrefu pamoja na majaribio ya majaribio yanahitajika.