全球变暖与富营养化的协同作用研究：以湖泊沉积物为例

淡水生态系统极易受到气候变化的影响，其主要原因为（1）破碎化生境中的许多物种已很难应对各种环境的改变；（2）水温与水资源的可利用性与气候变化紧密相关；（3）生态系统已经受到许多人为因素的干扰。目前，大多数气候变化的研究多集中在个体和种群的水平，而对更高组织水平，如群落、食物网及生态系统影响的研究则相对较少。本研究拟选择长江中下游地区典型湖泊沉积物系统作为研究对象，采用实验生态学手段，模拟该地区百年后气候变暖的情景，探讨气候变暖是否会改变湖泊沉积物系统的结构与功能，以期揭示不同营养水平沉积物系统水平代谢平衡在全球变暖趋势下的响应特征；阐明气候变暖与富营养化的协同作用下，湖泊沉积物系统结构与功能的响应机制；揭示气候变暖在水体富营养化进程中的地位与作用。

Freshwaters are particularly vulnerable to climate change because (i) many species within these fragmented habitats have limited abilities to disperse as the environment changes; (ii) water temperature and availability are climate-dependent; and (iii) many systems are already exposed to numerous anthropogenic stressors. Most climate change studies to date have focused on individuals or species populations, rather than the higher levels of organization (i.e. communities, food webs, ecosystems). This study will mimick experimentally a scenario of global warming in sediment system of shallow lakes located in the middle and lower reaches of Yangtze River. The aim is to investigate whether a predicted temperature rise in the next century can change the structure and function of the sediment system. Questions to be addressed include (1) how metabolism balance in different trophic level of lake sediment system is response to global warming? (2) will global warming interact with increased nutrient supply to alter response mechanisms and variation characteristics of metabolism balance in lake sediment system? (3) will changing climate aggravate eutrophication symptoms