Latitudinal and altitudinal patterns of soil nematode communities under tallow tree (Triadica sebifera) in China

Because nematodes are an important component of soil ecosystems, patterns of soil nematode community structure along geographic gradients have received considerable attention. However, little is known about the multidimensional spatial patterns of soil nematode communities under specific plants. Here, we examined soil nematode communities associated with roots of tallow tree (Triadica sebifera) along a latitudinal gradient spanning from 19.44 degrees to 33.56 degrees N in China. On Tianzhu mountain in central China (30.69 degrees N), we also examined the distribution patterns of soil nematode communities associated with roots of T. sebifera along an altitudinal gradient spanning from 100 to 1000 m a.s.l. Through the integration of latitudinal and altitudinal gradients, our results show that latitudinal patterns of soil nematode community structure are mainly quadratic (low nematode abundance at mid-latitude), whereas altitudinal patterns are mainly linear (low nematode abundance at high altitude). Along with the differences in distribution pattern between latitudinal and altitudinal gradients, the relationship of factors to soil nematode community structure was also quite different in the two surveys. These results suggest that multidimensional and multifactorial studies are essential for revealing spatial distribution patterns, as well as the driving mechanisms, of soil nematode community structure.