开垦利用对东祁连山高寒灌丛草地土壤养分含量的影响

对同一海拔高度的东祁连山金露梅、山生柳高寒灌丛草地以及灌丛草地开垦后种植燕麦的土地,进行了土壤养分含量的研究.结果表明:金露梅灌丛草地和山生柳灌丛草地的土壤养分含量除全钾外,其他元素都是随土层加深而下降,且各土层差异显著(P<0.05).燕麦地除了全钾、速效钾、速效锰外,都是随土层加深而下降,且各土层差异显著(P<0.05).山生柳灌丛草地与金露梅灌丛草地土壤养分差异不显著(P>0.05).但灌丛草地与开垦地土壤养分差异显著(P<0.05),并且开垦后种植燕麦的土壤养分含量明显受到人为的控制和干扰,其土壤有机质、全氮、速效氮、速效磷和速效锌含量均比灌丛草地高,而全磷、速效钾、速效铁、速效铜和速效锰含量比灌丛草地低,速效钾含量并不随土层加深而变化,速效铁和速效锰含量则随土层加深而上升.

Effects of the reclamation on soil nutrient contents in the alpine shrublands of the eastern Qilian Mountains

The nutrient contents of the soil in the Potentilla fruticosa shrub grassland,Salix oritrepha alpine shrublands and the oats field which used to be the alpine shrublands were investigated.The results indicated that the nutrient contents of the soil in the Potentilla fruticosa alpine shrublands and Salix oritrepha alpine shrublands,except for the total potassium,decreased with the depth of the soil layers.And there was an apparent difference among different soil layers(P<0.05).The nutrient contents of the soil in the oats field,except for the total potassium,available potassium,available iron and available manganese,decreased with the depth of the soil layers.And there was an apparent difference among different soil layers(P<0.05).The difference of nutrient contents of the soil between the Potentilla fruticosa alpine shrublands and Salix oritrepha alpine shrublands was insignificant(P<0.05),while it was significant between alpine shrublands and oats field(P<0.05).The nutrient contents of the soil in the oats field was controlled and interfered by the reclamation.The organic matter,total nitrogen,available nitrogen,available phosphorus,available zinc in the soil of the oats field were higher than those in the shrub grassland,while the total phosphorus,available potassium,available iron,available copper and available manganese were lower than those in the shrub grassland.The content of available potassium in the soil of oats field didn’t change with the depth of the soil layers,but the content of available iron and available manganese increased with the depth of the soil layers.