The Relationship Between Algae Biodiversity And Biomass Under Different Cadmium Stress:A Microcosm Experiment

Recently,as the speed of the species extinction is accelerating,what results it brings to ecosystem is concerned,and the relationship between biodiversity and ecosystem function has become an important science problem in ecology area.The world environmental pollution is one of the important causes results the species extinction.Our research using microcosm experiment which is popular in the study on biodiversity(1.Staursatrum sp.;2.Ankistrodesmus falcatus;3.Pediastrum sp.;4.Cosmarium botrytis;5.Coelastrum sphaericum;6.Scenedesmus quadricauda;7.Microcystis aeruginosa;8.Scenedesmus obliquus),studied the relationship between biodiversity and ecosystem function under different cadmium stress,and tried to explain the under mechanisms.Experiments show that in the absence of cadmium stress,biodiversity and ecosystem function(biomass and stability)are not relevant.While in addition to cadmium stress,biodiversity and ecosystem function are positively correlated with model complexity.And the system stability will increase when characterization of the biological diversity index increases.Our research proves that structure complexity of species composition is one of the main causes of ecosystem stability.The relationship between biodiversity and ecosystem function is dependent to environment.The key species in species composition is the key to analyze the impact of biodiversity on ecosystem function..And this key species has higher stability under stress conditions but not necessarily the dominant species in the community under no stress.It also shows that high biodiversity and more species composition will increase the stability of the ecosystem.lt will make the ecosystem more stable when subjected to external interference and stress.