摘要
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 soil ^(137)Cs radioactivity of field cultivated for different years and degradation pasture, the results showed that ^(137)Cs radioactivity was significantly reduced when pasture was degraded.Compared to 1ightly degraded pasture,the ^(137)Cs radioactivity in moderately degraded pasture and heavily degraded pasture decreased by 21%and 52%,respectively. And after 7-,15-,and 33-yr cultivation, the ^(137)Cs radioactivity was 37%,31%and 26% of that in 1ightly degraded pasture, respectively.Furthermore, the correlation analysis showed that the content of the soil organic matter, total soil N, and soil CEC dropped when soil erosion occurred. The content of soil organic matter,total soil N,soil exchangeable K and soil CEC showed the highest positive correlation with ^(137)Cs.
出处
《中国草地》
CSCD
2005年第3期11-14,20,共5页
Grassland of China
基金
国家自然科学基金项目(30170668
30371020)资助
