土壤粉尘释放能力与土壤性质关系的初步研究

Preliminary research on the relationship between soil dust emission ability and soil properties

土壤粉尘释放能力是决定区域粉尘释放强度的关键因素,但一直缺少适合的土壤性质指标进行表征。采用野外取样分析与风洞实验手段,就土壤粉尘释放能力与土壤性质的关系进行初步研究。结果表明:各种与风蚀相关的土壤基本理化性质中,只有粉沙和沙粒含量对土壤粉尘释放能力的影响较显著,土壤粉尘释放能力随土壤中粉沙和沙粒含量增加具有先增大后降低的趋势,支持了有关学者提出的中等质地土壤具有最强粉尘释放能力的观点。土壤粉尘释放能力与土壤干团聚体粒度组成关系紧密,具有随土壤可蚀性颗粒中粒径<0.05 mm细颗粒含量(C<_(0.05/<0.85))增加呈线性规律显著增加,随土壤可蚀性颗粒中粒径0.1~0.5 mm跃移颗粒含量(C_(0.1-0.5/<0.85))增加呈幂函数规律显著降低的趋势。各项土壤理化性质指标中,土壤干团聚体中粒径<0.05 mm细颗粒含量(C<0.05)不仅能够反映各种土壤基本理化性质对土壤粉尘释放能力的综合影响,而且与决定土壤粉尘释放能力的两个正向指标——土壤可蚀性颗粒含量(C_(<0.85))和C_(<0.05/<0.85)均呈显著的线性正相关关系,应是表征团聚体发育土壤表面粉尘释放能力较合适的土壤性质指标,这得到土壤样品分析结果的初步证实,但还需要进一步的实验验证。

The soil dust emission ability(SDEA)is a key factor to determine the regional dust emission amount,but there has been a lack of suitable soil property indicators to characterize.In this paper,the relation-ship between SDEA and soil properties is studied by means of field sampling and wind tunnel experiment.The results showed that only the content of silt and sand particles in soils has a significant impact on SDEA among the basic physical and chemical properties of soil related to wind erosion.The SDEA first increases and then decreases with the increase of silt and sand content in soils,which supports the viewpoint proposed by relevant scholars that medium texture soil has the strongest dust emission ability.The SDEA is more closely related to the particle size composition of soil dry aggregates,which increases linearly with the increase of the content of fine particles with a diameter of<0.05 mm in soil erodible particles(C_(<0.05/<0.85)),and decreases significantly with the increase of the content of saltation particles with a diameter of 0.1-0.5 mm in soil erodible particles(C_(0.1-0.5/<0.85))in a power function law.Among the various indicators of soil physical and chemical properties,only the content of fine par-ticles with diameter of<0.05 mm in soil dry aggregates(C_(<0.05))can reflect the comprehensive impact of various soil basic physical and chemical properties on SDEA,and is significantly linearly correlated with the two posi-tive indicators that affect SDEA,namely the content of soil erodible particles(C_(<0.85))and the value of C<_(0.05/<0.85).The C_(<0.05)should be a suitable soil indicator to characterize the SDEA for soil of aggregate development,which is confirmed by the analysis results of soil samples,but further experimental verification is needed.