Spectral measurement was applied to monitor degradation of steppe grassland in Inner Mongolia, China. Supply of drinking water for domestic animal is an important for nomadic peoples in Xilingol steppe. There is only one main drinking place (site-00) for animals at the center of Branch No.4 of Baiyinkulun Livestock Farm. So the distance from the village (site-00) can be used as an effective indicator for grazing intensity since the water tank in the village is the main drinking place for animals. In addition to the measurement of surface reflectance, vegetation surveys were carried out as a function of the distance from site-00 at every 1-㎞ interval to each four directions until the 5-㎞ point. It has cleared that the effects of grazing on vegetation mitigated according to the distance from site-00. Negative plant indicators of grazing intensity such as Stipa grandis increased in dominance with distance from site-00, whereas positive indicators of grazing intensity, such as Cleistogenens squarrosa decreased. Changes in growth parameters along the environmental gradients were reflected on NDVI (Normalized Difference Vegetation Index), in which NDVI was positively correlated with the aboveground biomass (r=0.77), plant height (r=0.69) and coverage (r=0.89), respectively. These results suggested that a spectral vegetation index is effective for the detection of the degradation in free grazing grassland.

• Tsuyoshi Akiyama
• Kensuke Kawamura
• Ayumi Fukuo
• Genya Saito
• Zuozhong Cheng