【摘要】 野外采样和室内分析相结合,对我国高寒地区荒漠化植被恢复不同阶段土壤生物结皮特性变化进行了研究。结果表明在沙质荒漠化地区,通过人工植被恢复,土壤生物结皮的形成是荒漠化土壤得以固定的基础,沙丘的固定时间不同,结皮层的特性有很明显的差异:①随固定时间变长,结皮层的土壤颗粒组成细化。结皮层砂粒总含量呈降低趋势,其中1~0.25 mm砂粒的含量逐渐降低,0.25~0.05 mm砂粒含量先升高后降低,而0.05~0.02 mm砂粒的含量在逐渐升高,粉粒和粘粒含量在固定初期呈逐渐增高趋势,之后趋于稳定;②固定过程中结皮层的化学性质逐渐变优。土壤结皮层的有机碳、速效养分、全氮含量及CEC均不断提高,说明结皮层对土壤养分有强烈的富集作用;碳酸钙和pH值没有十分明显的变化;有机物质的增多,促进土壤微生物的繁殖,从而促进土壤酶活性的提高。更多还原

【Abstract】 Based on field sampling and lab analysis,this article studied the sand-fixing characteristic of different stages after vegetation recovery of desertificated land in high frigid region.The results showed that the formation of sand-fixing through resuming the artificial vegetation in the sandy area is the base of the dune fixing,in different time of the sand dune fixing,the characteristic of sand-fixing has a very obvious difference: ① With long time of fixing,the soil textures thinning.In the sand dune fixing process,the total content of sand grain tends to gradually reducing,the 1～0.25 mm sand grain content reduces gradually,the 0.25～0.05 mm sand grain content first increases and then reduces,but 0.05～0.02 mm sand grain content increases gradually,the silt and clay content increases at beginning,then stabilizes.② The chemical property becomes gradually superior.With long fixing time,the soil organic carbon,the fast-acting nutrient,the total nitrogen content and CEC gradually increase,these show that the sand-fixing have a function of intensely concentrating the soil nutrient;But the calcium carbonate and the pH value does not have extremely obvious changes.The increasing of organic matter promotes the reproduction of the soil microorganism,thus promotes the improvement of the activation of the soil enzyme.更多还原