The invention discloses a
karst area soil
nutrient reserve sampling and calculating method. The method comprises the steps that: (1) a
dry land is selected at a
karst area; (2) the sample land is divided into small samples, and soil augers are firmly drilled into soil in every network; (3) a soil profile stratified sample is dug from every land sample according to soil average thickness, and soil unit weights are determined by using
cutting rings; (4) the soil samples are naturally air-dried in a shade, and are filtered;
plant roots in soil samples in the
cutting rings are removed, washed by using clear water, and bake-dried to constant weight; and the
plant roots are weighed, such that root biomasses are obtained; (5) according to a soil organic carbon content and soil unit weight relationship scatter-plot established according to
ecosystem soil profile data, organic carbon contents are determined, and soil unit weights are calculated; (6) soil
nutrient densities are calculated according to soil volumes; and (7) according to soil
nutrient densities of the samples of the
ecosystem, unit-area soil nutrient reserve is obtained. The method is simple, easy, convenient, time-saving and labor-saving, and has high
operability. With the method,
karst area soil nutrient reserve data can be accurately obtained.