Plant-Herbivore Interactions in the Pelagic Zone of Eutrophic Lakes

WPC0 2 B V T w# | x 10螺距z N x x x， x @；HP Laserjet （25-in-one, Network）PRS X X X X X X X, X @；HP Laserjet （25-in-one, Network）pprs X X 4 P RN h 0 s 2 &；本研究的重点是富营养化湖泊中水蚤与藻类之间的强相互作用。总体目标是量化水蚤死亡率与藻类总生物量之间的关系，研究初始条件作为浮游生物群落结构决定因素的作用，并量化藻类物种面对食草性限制的适应性权衡。本研究探讨了富营养化湖泊群落结构中是否存在多重平衡，这是由于水蚤和丝状蓝藻之间的相互负作用。此外，这项工作将通过检查藻类物种面临的适应性权衡来确定上述相互作用的一些机制。多重平衡的存在已被生态学理论所预测，但很少被实验证明。这对于生态学作为一门预测科学的发展是至关重要的，因为需要具体说明初始条件可能严重限制预测生态现象的能力。食物网在改善外延对水质的负面影响方面的作用，对于确定通过改变鱼类群落来减少富营养湖中藻类过度生长的管理目标也很重要。

WPC0 2 B V T W #| x 10 pitch z N x x x , x @ ; HP Laserjet (25-in-one, Network) HPLASEII.PRS X t 4 P RN h 0 IS 2 4 V F W Courier 10 pitch z N x x x , x @ ; HP Laserjet (25-in-one, Network) HPLASEII.PRS X t 4 P RN h 0 IS 2 & J . #| x 93083375 Sarnelle This research focuses on the strong interactions between Daphnia and algae in eutrophic lakes. The general objectives to quantify the relationship between the death rate of Daphnia and total algal biomass to examine the role of initial conditions as a determinant of planktonic community structure and to quantify adaptive tradeoffs faced by algal species to constraints imposed by herbivory. This research examines whether multiple equilibria exist in the community structure of eutrophic lakes, due to a reciprocal negative interaction between Daphnia and filamentous bluegreens. In addition the work will identify some of the mechanisms underlying the above interactions, by examing adaptive tradeoffs faced by algal species. %%% The presence of multiple equilibria has been predicated by ecological theory but rarely demostrated experimentally. This is crucial to development of ecology as a predictive science since the need to specify initial conditions may severely contrain the ability to predict ecolgical phenomena. The role of food webs in ameliorating negative effects of extroplication on water quality is also important to indentifying management targets for reducing excessive algal growth in nutrient enriched lakes via changes in the fish community.