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1、Ecology of freshwaters Lakes, rivers, and streams,Limnology,Lakes are born by catastrophe,age, and quietly die,rivers, and streams,Limnology,Rivers are ancient,Rivers carry sediment,Limnology,Rivers are ancient,Rivers carry sediment,meander,Limnology,A river creates its valley,Rivers are ancient,Riv
2、ers carry sediment,meander,Limnology,Estuaries,Limnology,Lakes & rivers differ in food chains,Lakes support photosynthetic chains,phytoplankton,Energy is autochthonous,Limnology,Lakes & rivers differ in food chains,Rivers support a detritus food chain,Energy is allochthonous,Limnology,Lakes are stra
3、tified,in temperature,a summer lake,Limnology,Lakes are stratified,in temperature,epilimnion mixes,hypolimnion stagnates,a summer lake,Limnology,Lakes are stratified,by light,photosynthesis,detritus,decomposition,nutrient rich sediment,a summer lake,Limnology,Lakes are stratified,There are 2 lakes,p
4、roductive epilimnion,detritus food chain releasing nutrients,during warm,phytoplankton starved for nutrients,a summer lake,months,Limnology,In the fall,surface water cools,40 C water sinks,fall turnover,phytoplankton blooms,nutrients returned,to epilimnion,Limnology,In the fall,surface water cools,4
5、0 C water sinks,fall turnover,phytoplankton blooms,nutrients returned,to epilimnion,Limnology,In the winter,lake is sealed,Limnology,In the spring,spring turnover,nutrients mixed into epilimnion,phytoplankton bloom,Limnology,Lake food chain,phytoplankton,zooplankton,nekton,Limnology,Zooplankton migration,Limnology,The Lake as a Microcosm - Steven J. Forbes,Limnology,An ecosystem united,seasonally,