01679nas a2200145   4500008004100000245006700041210006700108300001300175490000700188520118200195653002201377100002001399700001901419856009501438       1986                        eng d00aDetritus accumulation limits productivity of tallgrass prairie0 aDetritus accumulation limits productivity of tallgrass prairie  a662 -6680 v363 a<p>A number of ecosystems in North American are maintained by fire, and other systems such as the Serengetti grasslands and taiga forest decline in productivity when fire or grazing is excluded. We believe, however, that the tallgrass prairie is unique among the North American biomes because of the strong negative impacts of plant ligtter production on subsequent ecosystem function. These deleterious effects on plant litter include: a reduction in available light energy to the system; an alteration of the microclimate and physiology of emerging shoots such that carbon dioxide uptake is reduced; a conversion of immediately usable inorganic notrogen in rainwater to less readily available organic nitrogen in microbial biomass; an inhibition of nitrogen fixation by free living microbes and blue-green algae as a result of phosphorus and/or light limitation; and a reduction in soil temperatures, which diminishes root productivity, invertebrate activities, and probably microbial activities as well. Fire and grazing therefore become necessary, integral ecosystem processes that maintain productivity of tallgrass prairie by the removal of standing and fallen litter</p>10atallgrass prairie1 aKnapp, Alan, K.1 aSeastedt, T.R.  uhttp://knz.lternet.edu/content/detritus-accumulation-limits-productivity-tallgrass-prairie