Effects of different soil surface management on distribution characteristics of pear roots

The effectiveness of fertilization relies on the distribution of pear tree roots in soil heavily. Excavating method was used to study the horizontal and vertical distributions of root length, root surface area, root volume and root distribution characteristics of different with diameters under three different soil surface management (open, growing clover, plastic mulching). Results show that the horizontal distribution of tree roots is mainly concentrated in the 30-90 cm from the trunk, and the vertical distribution is centralized in the 20-60 cm deep of soil layer. The root length, root surface area and root volume for interplanting white clover and plastic mulching are higher than those of the control treatment. Under the three soil surface management, the root length and biomass of 0-1 mm are the highest in different diameter classes, and the root surface area of 1-3 mm is the highest. The total length and surface area of roots in the inter-planting white clover treatment are the largest, while the root volume is the least. Based on the results, we can recommend the fertilization in the horizontal distribution of 30-90 cm and in the vertical distribution of 20-60 cm may promote root growth of pear trees and the utilization of fertilizers.