吉林省土壤中有效锰、铜、钼和锌含量的时空变化

选择吉林省的五个大豆种植区(敦化、桦甸、榆树、农安、白城)、四个水稻种植区(白城、九台、延吉、梅河口)及3个草场分布区(镇赉、洮南、大安)，对其土壤中有效锰、铜、钼和锌的含量在过去20年的变化作了比较和分析。经研究表明：吉林省土壤中有效锰和有效铜含量较20年前有所增高，有效钼含量总体呈降低趋势，中部部分地区和东部地区土壤有效锌含量降低，其余地区含量增高。空间分布东部高于中西部。

Spatial and Time Variation of Available Mn, Cu, Mo, Zn in Soils from Jilin Province

According to the contents of available Mn, Cu, Mo, Zn in soils of five soybean croplands, four rice croplands and three prairies in Jilin Province, the article compares and analyses the spatial and time variation during the past two decades. The result indicates that the available contents of Mn and Cu increased and the available content of Mo declined. The content of available Zn decreased in soils of some middle and east regions, while it has increased in other regions. The spatial analyses show the soils of east region having more trace elements than those of middle and west regions.