Effects of land use intensity on the restoration capacity of sandy land vegetation and soil moisture in fenced sandy land in desert area

摘要

Effects of different land use intensity (phytomass semi-cutting and all-cutting) on structure characteristics of plant community and soil moisture in a natural vegetation enclosure and an artificially-aided enclosure were investigated in a sandy grassland in Northern China. No-cutting (phytomass kept nomal) was taken as the control treatment (CK). Analyzes showed that: 1-Importance value of the dominant species of different cutting treatments was in the range of 0.47-0.75. The influence of different cutting intensities on species composition was not significant for the same fenced method; 2-Both the diversity indices and the evenness index of shrub layer for the two enclosures were in the order: CK > semi-cutting > all-cutting; the similar indices of the plots of same cutting intensity and different fenced methods were smaller than 0.3; 3-The above-ground biomass of all-cutting treatment was significantly less than that of semi-cutting treatment, and CK had no significant difference from semi-cutting treatment; 4-There were significant differences in soil moisture between all-cutting and semi-cutting. The soil moisture of different layers within 80 cm increased with the increase of cutting intensities. In 0-30 cm, the soil moisture in different cutting intensities was increased with depth; however, in 30-70 cm, it decreased quickly with the increase of soil depth. Soil moisture under different cutting intensities and CK was in the following order: all-cutting > semi-cutting > CK. It proved that land use has some regulation and improvement effects on soil moisture.