Plant roots and anti-scourability of soils in the Shangshe Catchment, Dabie Mountains, Anhui Province, Eastern China

Abstract

The distribution of root biomass was studied in different soil layers (0―10, 10―20, 20―30, 30―40?cm) by means of a “study plot” method for various plant species in the Shangshe Catchment area in the Dabie Mountains, Anhui Province. The number and lengths of root samples were recorded. In each study plot, anti-scourability of soils in corresponding soil layers was measured with a C.C. Suoboliefu anti-scourability instrument. The results showed the following: 1) The root system was largely distributed in the 0―40?cm soil layer and the number of roots was the largest in the surface soil layer. Fine roots <1?mm in diameter predominated in root length. 2) In the same section, the anti-scourability indices of the surface soil layer were larger than those of other soil layers in the various plant species. The tree root system, especially the fine roots <1?mm in diameter, are highly instrumental in controlling soil losses. Correlation coefficients of length, number and density of fine roots and the anti-scourability index were 0.8173, 0.7159 and 0.6434, respectively. The length of fine root is a key factor in the anti-scourability soil index. This index is closely correlated with the non-capillarity of each soil type, indicating that forests have a strong soil stabilizing function, because their root systems improve physical soil properties and ultimately are responsible for the establishment of a bio-soil system with an anti-scourability index.

Keywords

Shangshe Catchment / root system / soil anti-scourability index