古浪灌区土壤耕层有效锌、锰、铜、铁

摘要：在2009-2010年，对古浪县井灌区、河灌区和引黄灌区326个土壤样点的耕层有效锌、锰、铜、铁含量进行定量监测分析，旨在为该区土壤合理施肥提供科学依据。结果表明，井灌区、河灌区和引黄灌区分别有81.6%、67.1%和41.7%的耕地土壤有效锌含量低于作物的需锌临界值，缺锌状况比较严重；3个灌区土壤有效锰含量分别为5.64～10.12、6.46～14.68和7.22～15.17 mg/kg，有效铜含量分别为0.42～1.12、0.90～2.00和0.81～2.47 mg/kg，均高于作物需锰（5.0 mg/kg）和铜临界值（0.2 mg/kg），属高含量水平；3个灌区土壤有效铁含量分别为2.88～8.08、2.42～13.19和2.61～14.22 mg/kg，平均为5.40、10.20和12.30 mg/kg，虽高于作物需铁临界值（4.5 mg/kg），但3个灌区仍分别有18.5%、6.4%和3.7%的耕地土壤有效铁含量低于作物需铁临界值。因此，3个灌区土壤耕层土壤有效锌含量严重缺乏，有效锰和有效铜含量丰富，局部地方缺铁；3个灌区种植作物时均需施锌肥，适当施铁肥，不需施锰和铜肥，施肥量依作物种类和土壤状况不同而异。

Analysis and evaluation of available Zn,Mn,Cu and Fe contents of topsoil in Gulang Irrigation Region

To provide a scientific basis for rational fertilization,the available Zn,Mn,Cu and Fe contents of top soils in 326 different sampling points that belonged to well irrigation areas,river irrigation areas and Yellow River irrigation areas were detected and analyzed from 2009 to 2010.The results showed that the available Zn contents in 81.6% of the well irrigation area soils,67.1% of the river irrigation area soils and 41% of Yellow River irrigation area soils were lower than the critical value of the plant Z...