青海湖沙区风沙土土壤机械组成特征

Characteristic of mechanical composition of Aeolian sandy soil in desert area around Qinghai Lake

【目的】掌握青海湖沙区土壤颗粒物组成特征,为防治措施生态效益的定量评价提供依据.【方法】选择青海湖沙区的典型样区,通过野外调查、采样及室内实验分析,对青海湖沙区风沙土的颗粒组成特征进行研究.【结果】青海湖沙区示范区的草方格设置从2008年才开始,属固沙的初步阶段,颗粒较粗,颗粒组成与流动沙丘相似,颗粒组成以较粗的颗粒为主.海晏县克土为早期治理区,各样点均以粒径0.25-0.5mm的中沙颗粒为主,栽植青杨和沙棘的草方格中的粗沙含量较植被覆盖较高的早期治理区高,粉沙和极细沙几乎为零.湖东-种羊场草方格中的风沙土颗粒组成以0.1-0.25mm的细沙为主,0.25-0.5mm的次之,其他粒径的颗粒含量均非常少.沙岛治理区中风沙土颗粒以中沙和细沙为主,其他粒径的颗粒含量均较少.流动沙丘的中沙和粗沙含量较高.示范区的草方格与流动沙丘颗粒组成均表现为以中沙和细沙为主.【结论】沙漠化治理年限较长的区域,植被覆盖较好,风沙土颗粒较细.

【Objective】The aim of this study was to master the sand grain composition characteristics of sand soil around Qinghai Lake.【Method】Selecting typical sampling area in desert area around Qinghai Lake,the soil granule composition of aeolian sandy soil was research by field investigation,soil sampling and laboratory analysis.【Result】Straw checkerboard barriers were set in demonstrate area in the sandy area,which belonged to initial stage,particles were coarse,particle composition was similar to that of moving sand dunes and particle composition was mainly composed of coarse particles.Early controlled areas of Ketu in Haiyan county,middle-sized sand particle was mainly composed of particles with diameter at 0.25-0.5mm.The content of coarse sand in straw checkerboard barriers planted Populus cathayana and Hippophae rhamnoides was higher than that in early controlled areas and silt and mighty fine sand were few.And lowland of sand soil particles was higher in 0.25-0.5mm,and fine sand,silt and coarse sand were low.Particles of 0.25-0.5mm were higher in straw checkerboard barriers zone planted with Hippophae thibetana Schlechtend and Populus cathayana Rehd.And coarse sand content was higher than early combating areas,silty sand and fine sand was few.In straw checkerboard barriers at Hudong Sheep BreedingFarm,aeolian sandy soil particle was mainly composed of fine sand with diameter at 0.1-0.25 mm,followed by 0.25-0.5 mm and other particle sizes were very few.In Shadao combating zone,particle was mainly comprised by middle-sized and fine sand and other particle sizes were very few.Middle-sized and coarse sand content was higher in mobile dune.Particle composition was composed of middle-sized and fine sand in the straw checkerboard barriers in demonstration area and mobile sand dune.【Conclusion】The areas implemented sand control for many years characterized good vegetation coverage and finer soil granule.