Abstract:
Soil physical properties are the important indicators for evaluating soil structure and function. Exploring the effects of soil and water conservation measures on soil physical properties in small watersheds will be beneficial to provide a theoretical basis for the ecological environment construction and anti-erosion measures. In this study, Tongshuang small watershed in Baiquan County, Heilongjiang Province was selected as the research object. Five soil physical properties, including soil bulk density, soil field capacity, soil saturated water content, soil water stable macroaggregate content (WR
0.25) and mean weight diameter (MWD), were selected through field sampling. The spatial differentiation characteristics of soil physical properties were analyzed by classical statistics, geostatistics and information entropy, and the correlation between soil and water conservation measures (terrace, contour ridge, forestland, grassland and shrubland) and soil physical properties was studied. The results showed that the surface soil bulk density, field capacity, saturated water content and MWD in Tongshuang small watershed were moderately variated, while soil WR
0.25 was weakly variated. The soil physical properties were spatial autocorrelated moderately and exhibited patchy or banded distribution in space. The information entropy showed that there was a spatial correlation between soil physical properties and soil and water conservation measures, with the order of soil bulk density, soil field capacity / soil saturated water content, MWD and WR
0.25. There were significant differences in soil physical properties among different soil and water conservation measures. The soil bulk density of arbor forest was significantly higher than that of terrace, contour ridge and shrubland; the soil moisture characteristics were significantly lower than that of terrace, contour ridge and shrubland; and the soil WR
0.25 content and MWD of grassland were significantly higher than those of terrace and contour ridge.