从沙物质粒度分析结果研讨沙生植物的固沙作用

Research on sand-fixation role of desert plants based on analysis of sandy soil sizes

在库布齐沙漠西部地区固定半固定沙丘柽柳、梭梭、白刺、油蒿、花棒等沙生植物生长区,通过对表面干沙和深层湿沙的沙粒粒径进行对比分析,获得以下数据:表面干沙和深层湿沙极粗沙、粗沙、中沙、细沙、极细沙、粉沙的含量分别为0.14%、0.10%、0.24%、72.90%、24.12%、1.85%;0.04%、0.05%、0.27%、79.20%、19.30%、0.55%。从总体上看,表面干沙的沙粒细沙、极细沙百分含量高于深层湿沙,说明取样时取样点处于堆积状态,细沙、极细沙、粉沙(0.25～0.05mm)的含量高达98.87%。由于沙生植物的固定、尘土的堆积和成土作用,固定半固定风沙土的粉粒和粘粒含量逐渐增加。随着有机质和粘粒的增加,土壤结构改善,微因聚体增加,容量减小,孔隙度提高。试验证明沙生植物灌丛下的沙粒粒径比流动沙丘沙粒粒径细,充分体现了植物改良沙质土壤的作用。

An transverse comparison on sandy soil particle sizes of the surface dry sand and in-depth wet sand in western regions of Kubuqi desert where Haloxlon ammodendron Bge,Nitraria tangutorum Bobr,Artemisia ordosica Krash,Ulmus pumila and some desert plants grow had been done.The results were as follows： The contents of extreme coarse sand,coarse sand,fine sand,extreme fine sand,fine-grained sand on surface dry sand and in-depth wet sand were 0.14%,0.10%,0.24%,72.90%,24.12%,1.85%,0.04%,0.05%,0.27%,79.20%,19.30%,0.55% respectively.In General,the percentage of fine sand,extreme fine sand on the surface dry sand was higher than that in wet sand,which showed that samples were under the stack condition,The contents of fine sand,extreme fine sand and fine-grained sand were up to 98.87%.Because the desert plants could fix and stack sand,the contents of particles and clay particles of the sand were gradually increasing.As the amount of organic matter and clay particle increased,the structure of soil had been improved,the capacity had been decreased,and the porosity had been enhanced.Experiments proved that the sandy soil sizes under desert plants were smaller than that in wandering dune.It fully embodied the amelioration of plants to sandy soil.