| In this study, TDR soil moisture testing and the speed measurement method used by Ministry of Agriculture in United States in soil stability and vegetation canopy gap were adopted, and combined with conventional methods used in soil properties and lawn vegetation characteristics analysis, to study soil moisture, soil properties and grass vegetation characteristics on desert steppe in Siziwang county, Ulan Qab city, Inner Mongolia. The experimental area was divided into four: heavily grazed area (HG),moderately grazed area (MG), lightly grazed area (LG) and CK area (CK). The major findings were as follows:(1) The values tested by TRIME-IPH testing equipments were rather accurate and stable and share a high correlation with the values tested by the drying method, so it could be used in monitoring soil moisture of the desert steppe. (2)In CK,MG and HG, soil moisture in different grazing intensity areas in 2009 was lower than in 2008.Soil moisture in 2008 showed as CK>LG>MG>HG,while soil moisture in 2009 showed as LG>CK> MG >HG. Soil moisture under different grazing intensities in 2008 was higher than in 2009. (3) The soil moisture in the experimental area showed an upward trend from south to north and a downward trend from west to east. With increasing grazing intensity, soil moisture decreased gradually. 5-7 month soil moisture declined, 7-9 months raised up to the level in May gradually, and declined gradually to the minimum after September.(4)Soil stability: In 2008, soil stability of bare land and soil near vegetation in the experimental area showed a decrease trend with increasing grazing intensity. In 2009, the soil stability of the soil near vegetation was decreasing with grazing intensity increasing, soil stability of the bare land in experimental area was LG> CK> MG> HG.(5)In 2008 and 2009, soil compaction strengthened with grazing intensity increasing; in 2008, soil compaction of CK,LG and HG area was higher than in 2009, only in MG area, soil compaction was lower than in 2009. (6)Under different grazing intensity, available nutrients (available phosphorus, available potassium, nitrogen) showed as LG> CK> MG> HG. Total nitrogen showed as CK> LG> MG> HG. Total phosphorus and organic matter showed as CK> LG> HG> MG. Total potassium showed as MG> CK> LG> HG.(7)With increasing grazing intensity, grass density and weed density showed a downward trend. In which, grasses density of LG and MG area were basically in the same level; Shrub density showed as CK> HG> LG> MG.(8)Litters in MG area were less than in HG area. Grass yields showed as CK≈LG> MG≈HG. Shrub biomass showed as CK> LG≈HG> MG. Weed biomass (including Compositae and Leguminosae that the livestock likes to eat) decreased with grazing intensity increasing.(9)In 2008, the canopy gap in CK,LG and MG area was dominant with gap of <25cm, 25-50cm and 51-100cm, HG area was dominant with gap of 101-200cm,> 200cm. In 2009, the canopy gap in all the grazing areas was dominant with gap of 25-50cm and 51-100cm, canopy gap <25cm in CK, LG and MG area significantly decreased, canopy gap > 200cm in HG area significantly decreased compared to 2008.(10)Grasses cover( % ): CK≈LG>MG>HG. Weed cover ( % ): CK>LG>MG>HG. Shrub cover(%):CK>MG>LG>HG.
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