Warming and leaf litter functional diversity, not litter quality, drive decomposition in a freshwater ecosystem

Abstract

Environment, litter composition and decomposer community are known to be the main drivers of litter decomposition in aquatic ecosystems. However, it remains unclear whether litter quality or functional diversity prevails under warming conditions. Using tank bromeliad ecosystems, we evaluated the combined effects of warming, litter quality and litter functional diversity on the decomposition process. We also assessed the contribution of macroinvertebrates and microorganisms in explaining litter decomposition patterns using litter bags made with different mesh sizes. Our results showed that litter decomposition was driven by litter functional diversity and was increasingly higher under warming, in both mesh sizes. Decomposition was explained by increasing litter dissimilarities in C and N. Our results highlight the importance of considering different aspects of litter characteristics (e.g., quality and functional diversity) in order to predict the decomposition process in freshwater ecosystems. Considering the joint effect of warming and litter traits aspects allow a more refined understanding of the underlying mechanisms of climate change and biodiversity shifts effects on ecosystem functioning.

Simulation of Freshwater Ecosystem Service Flows under Land-Use Change: A Case Study of Lianshui River Basin, China

“…We fixed the meteorological data in 2000, stripped off the impact of land-use change, and found that the land-use change in the river basin expanded the impervious layer area and increased the water supply by 0.01 billion m 3 from 2000-2018. This conclusion is consistent with the conclusions of [16,45] and others. The increase in construction area has led to an increase in water demand.…”

“…Watershed freshwater supply increases with land-use changes and responds differently to changes in land-use types. This is due to the internal flow and base flow generated by different land cover surfaces [16]. In the past, there have been many studies on the impact of land-use change on water supply [21,43], but most of them did not distinguish between the impact of climate change and land-use.…”

“…In addition, land-use may also have an impact on the annual runoff, dry season runoff, and flood peak discharge in the basin, which are mainly reflected in the change of water resources in the water cycle and the change of spatial and temporal distribution pattern, which will lead to significant changes in the relationship between water supply and demand in different regions, thus indirectly affecting water ecosystem services [14,15]. Many studies have analyzed the impact of land-use changes on freshwater ecosystem supply, but few studies have conducted quantitative analysis on the flow of freshwater ecosystem services under land-use changes [16,17].…”

Bacterial Metabolic Potential in Response to Climate Warming Alters the Decomposition Process of Aquatic Plant Litter—In Shallow Lake Mesocosms

“…Coniferous forests have lower nutrients (such as nitrogen and phosphorus) and higher structural components (such as lignin and cellulose) and recalcitrant compounds (such as tannins and polyphenols) than broadleaved forests, and therefore decompose more slowly [ 100 , 101 ]. Therefore, considering the joint effect of warming and litter traits aspects allow a more refined understanding of the underlying mechanisms of climate change effect on ecosystem functioning [ 7 , 102 ].…”

“…Xu et al (2020) [ 6 ] found that warming accelerated the growth and senescence of P. crispus , suggesting a more important role in maintaining the clear water state in winter–early spring but concomitant to possible earlier turbid states in summer [ 3 , 6 ]. The decomposition and recycling of P. crispus are also key processes in the aquatic ecosystem, linking nutrient cycle and energy transfer between water and sediment [ 7 ].…”