The role of nutrient variability in aquatic ecosystems

摘要: The effects of nutrient input into aquatic systems has been studied frequently; typically, these studies report an increase in algal biomass and a decrease species diversity response to nutrients. However, it is not clear why similar communities will respond differently additions magnitudes, resulting alternative communities. Because variance natural ecosystems pervasive, perhaps this variability that helps determine the final community. I proposed total amount would affect abundances composition species. A survey was conducted measure variable levels nutrients several systems. Experimental ponds were used test rates timing inputs upon community; experimental treatments manipulated (high v. low), rate (annually, monthly or weekly), (early mid- season), trophic status at which imposed (mesotrophic eutrophic). least as important input. There large impacts diversity, composition. Although manifested many groups, most strikingly found within primary producers, showed shifts abundance