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根据不同退化程度草原和不同开垦年限农田土壤137Cs放射强度分析结果表明:与轻度退化草原相比,中度退化和重度退化中的137Cs放射强度分别下降了21%和52%。草原土壤开垦后,137Cs放射强度明显下降,开垦7年、15年、33年后,137Cs的放射强度分别只有轻度退化草原的37%、31%和26%。相关分析表明,伴随着土壤侵蚀的发生,土壤有机质含量、全N含量以及阳离子交换量下降。137Cs放射强度与土壤有机碳、土壤全N、交换性K和阳离子交换量呈极显著的正相关。
According to the analysis of 137Cs emission intensity of different degraded grasslands and cultivated land with different reclamation years, the 137Cs emission intensity decreased by 21% and 52% respectively compared with the mildly degraded grassland. After the reclamation of grassland soil, the 137Cs emission intensity decreased obviously. After 7 years, 15 years and 33 years after reclamation, the 137Cs radiation intensity was only 37%, 31% and 26% of the mildly degraded grassland respectively. Correlation analysis showed that with the occurrence of soil erosion, soil organic matter content, total N content and cation exchange capacity decreased. There was a significant positive correlation between 137Cs emission intensity and soil organic carbon, soil total N, exchangeable K and cation exchange capacity.