01366nas a2200157   4500008004100000245009500041210006900136260003000205300001000235520077300245100001701018700002401035700001601059700001701075856011601092       1997                        eng d00aLandscape gradients and habitat structure in native grasslands of the central great plains0 aLandscape gradients and habitat structure in native grasslands o  aNew YorkbSpringer-Verlag  a3 -193 aHabitat variables have a powerful influence on the distribution and abundance of organisms, and many organisms directly affect the physical structure of their local environment. These interactions produce a complex feedback system that drives community dynamics. This scenario is particularly true in grasslands where the effects of “keystone engineers,” such as the North American bison (Bison bison), have a tremendous influence on ecosystem structure and function (Collins and Benning 1996). This interplay between organisms and habitat structure in grasslands occurs within a climatic regime that varies dramatically from one year to the next. In addition, the relative influence of different habitat variables changes at different spatial and temporal scales.1 aVinton, M.A.1 aCollins, Scott., L.1 aKnopf, F.L.1 aSamson, F.B.  uhttp://knz.lternet.edu/content/landscape-gradients-and-habitat-structure-native-grasslands-central-great-plains