检索规则说明:AND代表“并且”;OR代表“或者”;NOT代表“不包含”;(注意必须大写,运算符两边需空一格)
检 索 范 例 :范例一: (K=图书馆学 OR K=情报学) AND A=范并思 范例二:J=计算机应用与软件 AND (U=C++ OR U=Basic) NOT M=Visual
作 者:杨学明[1] 张晓平[1] 方华军[1] 梁爱珍[1]
机构地区:[1]中国科学院东北地理与农业生态研究所,吉林长春130012
出 处:《地理科学》2004年第6期710-714,共5页Scientia Geographica Sinica
基 金:国家自然科学基金资助项目(40271108);中国科学院国外杰出人才支持项目(C08k9);长春市科技攻关项目(02-111G03)。
摘 要:黑土有机质含量的变化一直倍受社会关注。根据第二次全国土壤普查的采样记录,2001年在吉林省黑土区采集了27个土壤样品,分析测定了耕层土壤(深度与第二次土普数据相同)的有机质和全氮含量。与第二次土普查数据对比发现,过去20年间,吉林省黑土土壤有机质和全氮含量有增有减,但平均水平无明显变化。与已有的研究对比分析,高产玉米生产条件下的根系碳输入量可能抵消矿化损失的有机质量,使水土流失不严重区域的黑土土壤有机质水平维持平衡,有机质含量下降的土壤可能是水土流失的结果。而在水土流失不严重地区土壤有机质则可能增加。Black soils are main agricultural soils in Northeast China and the organic matter content of these soils has been one of the hot research topics for many years. By referencing the data and sampling locations in the Second National Soil Surveys of Jilin Province conducted in the 1980s, we re-sampled 27 black soils along the Jing-Ha (Beijing-Harbin) railway in central Jilin. The contents of soil organic matter and total nitrogen of those soils were determined and compared in pair with the data measured 20 years ago on an equivalent depth. We found that 2-decades intensive farming affected differently the contents of soil organic matter and total nitrogen, with increasing for some soils and decreasing for others. However, there was no significant difference in overall average of soil organic matter. By comparing the results with other studies, we believe that the present corn dominated production has balanced soil organic matter level of black soils through roots alone in areas where soil erosion was not a problem. However, the soils that organic matter decreased during the past two decades might be subject to severe soil erosion. During the same time, some black soils gained organic matter.
分 类 号:S153.621[农业科学—土壤学] S153.61[农业科学—农业基础科学]
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在链接到云南高校图书馆文献保障联盟下载...
云南高校图书馆联盟文献共享服务平台 版权所有©
您的IP:216.73.216.15