Soil Stable Carbon Isotope Characteristics After Grassland Reclaimed To Farmland

Based on the stable carbon isotope(?¹³C)technique,this study selected five grassland meadows,desert grasslands,typical grasslands,subalpine meadows,and mountain grasslands with corresponding latitude gradients from south to north in China.The effect of grassland reclamation on soil organic?¹³C value was analyzed at five reclaimed grasslands.The results were shown as follows:1.The?¹³C values of farmland soil were 1.49‰higher than that in grassland soil in the northern area of Tongliao and Zhaohe,Inner Mongolia;the soil?¹³C value of cropped island was higher than grassland in 5¹0cm soil layer;the?¹³C values of farmland soil in the southern part of Hongyuan Country of Sichuan and Dushan Country of Guizhou were 1.415‰lower than that in grassland soil.2.The influence of soil?¹³C values is not only on above-ground plants,but also the climate and other environmental factor.3.The?¹³C value of the maize leaf and root system were gradually increased.4.In this paper,the average annual temperature in the grazing grassland and the reclamation farmland.The different of soil?¹³C in the north and south areas will be a new challenge to the soil micro-research.