Comparison Of Different Methods For Dry Soil Aggregate Stability And Soil Aggregate Of Different Land Use

Soil erosion is wind soil erosion,transportation,accumulation processes.Destroy the surface of soil wind erosion,resulting in loss of soil nutrients,leading to desertification.Soil erodibility is an important aspect of research on soil wind erosion,soil aggregates are important parameters influencing soil erodibility,decided its composition and basic characteristics of soil erosion and compaction,crusting and other physical process and one of the key indicators,but also based on soil fertility and an important indicator for evaluation of soil quality.Based on soil wind erosion(EF),mean geometric diameter(GMD),average quality diameter(MWD),the analysis of the fractal dimension d,can further illustrate aggregates characteristic indirect quantitative soil erodibility,under flat screen and rotating screen the two screening methods on effect of aggregate indicators are rare.So,paper selected Hebei dam Shang kangbao territory four farm class(grass,and woodland,and left stubble to,and turned arable land)74 a soil samples,on soil samples for flat screen,and spin screen screening and soil physico-chemical nature processing,compared soil dry reunion body grain diameter distribution,to inquiry flat screen and spin screen for soil dry reunion body index and soil mechanical composition of effect,different land using way between of dry reunion body index differences,then evaluation this regional within soil can corrosion sex status,,research results showed that:(1)through on flat screen,and spin screen by obtained of soil grain degrees composition for Mann-Whitney u test of differences sex analysis found,flat screen and spin screen to 0.84 mm grain level for points different boundaries,small grain level(>20mm,and 20-5mm,and 5-2mm,and 2-0.84mm)differences sex significantly,rendering out big grain level of soil particles differences sex significantly,and small grain level not significantly of phenomenon.Due to the high gravel content in the area of peace screen beat the shock effect of gravel in large aggregates,have influences on soil composition,size larger soil particles of corrosion is caused by broken grains increased,showing a trend of decreased EF values greater and EF values flat screen above the rotating screen.(2)through on GMD,and WMD,and d dry reunion body index for two Yuan correlation analysis and Mann-Whitney u test differences sex analysis,in flat screen,and spin screen reunion body index two Yuan correlation analysis in the,GMD,and WMD,and d,and EF are rendering very significantly are related;d,and EF index differences sex not significantly,EF(<0.84mm)soil grain degrees composition are for very significantly are related,with small grain level(<0.5mm)(3)flat screen and rotary screen of the fractal dimension d and small size is a significant negative correlation,and flat screen and rotary screen d correlated but the difference was not significant.Flat screen and spin screen of GMD,and WMD Zhijian differences sex significantly,and rendering flat screen is greater than spin screen of situation;d in different to class are and gravel content rendering significantly negative related,and GMD and WMD index only in woodland to class in the and gravel content exists significantly correlation,d and different grain level of correlation analysis in the also is better than GMD,and WMD,so,d in characterization different to class soil of grain degrees composition of capacity strong Yu GMD,and WMD index,The fractal dimension d soil erodibility and soil erosion status compared to the GMD,WMD are more stable,and found the fractal dimension d is more sensitive for small size description,while GMD,more sensitive indicators of WMD for a large particle size soil.(4)in different types of soil in average value for aggregate data analysis,woodlands on flat screens and rotating screen for most corrosion resistance class,GMD,WMD mean highest lowest d,EF.Stubble land of anti-erodibility is superior to plough,stubble to EF under plough,and GMD and WMD than plough,stubble land of d is less than.Shelterbelts and stubble of cultivated land as the main means of controlling wind erosion in bashang area has obvious effect of corrosion resistance,ecological benefits.(5)flat screen,and spin screen as screening soil grain degrees composition of first steps for soil wind erosion research produced based sex effect,its for soil grain degrees composition of effect will will further effect soil dry reunion body index,paper on flat screen of GMD,and WMD value above spin screen,in soil mechanical composition of big grain level(>20mm,and 20-5mm,and 5-2mm,and 2-0.84mm)differences sex significantly of situation for has analysis,Use for soil wind erosion area with high gravel content screening possible errors;Correlation of GMD,WMD,d,EF analysis,flat screen and rotary screen to maintain the consistency of the correlation analysis between the indexes,but rotating screen correlation coefficients are higher than the flat screen,the correlation between rotating screen were better than the flat screen.Therefore,rotating screen compared to flat sieves for soil screening and soil particle size reduction has certain advantages.(6)through EF,GMD,WMD,d and correlation analysis of soil physical and chemical properties,soil composition found in EF in the study area,d and gravel around the content in the category were significantly related to soil anti-erodibility index more under the influence of high gravel content.Organic matter,calcium carbonate and EF,GMD,WMD dry aggregate indicators in woodland,stubble fields,plough the relevance of the poor.Grassland type aggregate index in correlation with the organic matter is better,organic matter and clay to the grass in the formation of soil aggregates.Plough and stubble land due to the farming system,decentralized management of farmland affected,due to the protection of forest land planting spacing,to species,age,and other factors,as well as the long-term erosion leading to low organic matter content,soil GMD,WMD,d,EF and organic matter,calcium carbonate and clay,sand target in woodland,stubble fields,plough has no relevance.Therefore,high gravel content will influence the soil composition of different screen modes,and erosion due to the long suffering from erosion,higher the gravel content of soil,soil organic matter content is low,will cause the soil aggregate indicators of differences,impacts on the soil erodibility.