栽培对黑土线虫营养群体的空间分布的影响

Geostatistics combined with GIS was applied to assess the spatial distribution of nematode trophic groups following two contrasting soil uses in the black soil region of Northeast China.Two plots,one with fallow for 12 years and the other cultivated,were marked on regular square grids with 2-m spacing.Soil samples were collected from each sampling point,nematodes were extracted from these samples and classified into four trophic groups:bacterivores,fungivores,plant parasites,and omnivores/predators.The numbers of total nematodes and trophic groups analyzed had normal distributions on both fallow and cultivated plots.The absolute abundances of total nematodes and trophic groups were observed to be much nore homogeneous on cultivated plot than on fallow one.Geostatistical analysis showed that the densities of total nematodes and trophic groups on both fallow and cultivated plots exhibited spatial dekpendence at the sampled scale and their experimental semivariograms were adjusted to a spherical or exponential model,except those of bacterivores and fungivores oncultivated plot.The spatial distribution of nematode trophic groups was found to be different for the two land uses,indicating that cultivation changed the native condition for soil nematode activities.

Effect of cultivation on spatial distribution of nematode trophic groups in black soil

Geostatistics combined with GIS was applied to assess the spatial distribution of nematode trophic groups following two contrasting soil uses in the black soil region of Northeast China. Two plots, one with fallow for 12 years and the other cultivated, were marked on regular square grids with 2-m spacing. Soil samples were collected from each sampling point, nematodes were extracted from these samples and classified into four trophic groups: bacterivores, fungivores, plant parasites, and omnivores/predators. The numbers of total nematodes and trophic groups analyzed had normal distributions on both fallow and cultivated plots. The absolute abundances of total nematodes and trophic groups were observed to be much more homogeneous on cultivated plot than on fallow one. Geostatistical analysis showed that the densities of total nematodes and trophic groups on both fallow and cultivated plots exhibited spatial dependence at the sampled scale and their experimental semivariograms were adjusted to a spherical or exponential model, except those of bacterivores and fungivores on cultivated plot. The spatial distribution of nematode trophic groups was found to be different for the two land uses, indicating that cultivation changed the native condition for soil nematode activities.