| Line transect methodology were used to classify grazing intensity by means of freedom grazing pattern on natural grassland and to make sure specific grazing intensity grads. The structure and function of grassland ecological system and the affection mechanism of grazing intensity interfere were analyzed annually,seasonally. Part of index was analyzed annually and it showed that the different results were possibly due to different years and restriction of repeated sample number. By discussion of research theory and method of evaluation of grassland ecological system health and service value, new evaluation method was being quested. Illegibility mathematical method and CVOR (Condition, Vigor, Organization, and Resilience) were then used to evaluate the healthy condition of grassland ecosystem. Based on the grassland health evaluation, we appraised grassland ecosystem services value under different grazing intensities and ecosystem services, which were helpful to grassland ecosystem management and grazing effect mechanism. The main results were as follow:(1) Utilization of grassland vegetation identified different grazing intensity meaning, that is no grazing for the potential grassland (CK), grassland vegetation utilization 18.66 percent for the light intensity grazing (LG), grassland vegetation utilization 36.27 percent for the moderate intensity grazing (MG), and grasslands vegetation utilization 53.72 percent for the heavy intensity grazing (HG).(2) Lawn widespread spatial heterogeneity. With the increase of grassland grazing intensity, the spatial heterogeneity decreased. The status of grassland-based evaluation findings indicated that mild, moderate and severe grass-grazing conditions were 44.18, 38.03 and 25.75 respectively. A model for grassland monitoring was built, that is VO (Visual Obstruction M) readings and grassland vegetation existing in the regression model: Y = 20.13x +35.55, and the correlation coefficient is R = 0.80.(3) The grazing intensity and grassland climate have a significant influence on the net primary productivity. The changes of litter under different grazing gradient were obvious: CK> LG> MG> HG, and in October the volume is higher in October compared with the amount in May, The increase of grazing intensity will likely to promote grassland plant breeding. It was the result of cooperation between grassland plant populations and grazing. Severe grazing made the grassland plants in a small phenomenon.(4) Plant functional group plays a more significant ecological role in the grass functional group. The plot is dominated by grasses which also includes like grasses.Αdiversity index with the increase of grazing intensity demonstrated for the first increase, then decreasing trend, the value of grassland in the LG the greatest support "moderate interference theory",βdiversity index with the increase of grazing intensity and the different grazing intensity of the grassland species similar changes bad.(5) With the increase of grazing intensity, soil bulk density changed, but no grazing on the cumulative effect of soil bulk density; annual climate and the intensity of grazing can affect soil moisture, with the increase of grazing intensity soil moisture showed a downward trend, soil machinery Composition on sensitive grazing response, with the increase of grazing intensity increased sand content, silt content decreased, and no significant changes in clay; increased with soil depth of the sand content increased, reducing silt content, clay content did not change significantly; with the grazing intensity increased soil pH increased with the increase of grazing intensity decreased soil organic matter, soil nitrogen increased with the trend of soil phosphorus, and potassium do not change significantly. Available soil nitrogen, phosphorus and potassium in more affected by other factors, the relationship between grazing intensity and not obvious.(6) With the increase of grazing intensity, the number of soil microorganisms reduced. This is mainly because 89.19 percent of the total microbial bacteria decreased. Microbial biomass had a decreasing trend with the increase of grazing intensity. Soil urease, catalase, invertase, and protease had a decreasing trend accompanied with the increase of grazing intensity.(7) According to grassland ecosystem and the stability of the indicators of the sensitivity of grazing, a total of 11 "grass" system indicators and 12 "soil" system indicators were identified. Using CVOR Fuzzy mathematical methods and CVOR evaluation methods, grassland ecosystem health indicators under different grazing intensity were more consistent. Evaluation results of the two methods will be in CK Grassland ecosystem health indicators into one, the Fuzzy mathematical method for the evaluation of the results: the grassland of Potis 1,the grassland of LG is 0.97, the grassland of MG is 0.78, the grassland of HG is 0.65; CVOR evaluation Act for the results of the evaluation: the grassland of Pot is 1, the grassland of LG is 0.88, the grassland of MG is 0.73, the grassland of HG is 0.59; Grassland ecosystem health can be divided into health threshold (0.65~1), unhealthy threshold (0.30~0.65) and the collapse threshold (0~0.30) three health threshold level.(8) The value of unit area of grassland ecosystem service under different grazing intensity are: the grassland of Pot is US $ 376.59 / hm2 ? a; the grassland of LG is US $ 330.10 / hm~2·a; the grassland of MG is US $ 274.31 / hm~2·a; the grassland of HG is US $ 223.16 / hm~2·a, and the total sample of the ecosystem services valued is at US $ 1.13×10~4/ a. The sum of the values of all types of grassland ecosystem service in West Wuzhumuqin Banner were 466×10~8 US $ / a, which is 15.84 times of the total income.
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