Characteristics Of Soil Resources Occurrence And Small Climate In Typical Karst Micro-watershed

All we know that the soil resources in karst area are thin and low,but it has great influence on the restoration and reconstruction of ecology and the development of agricultural production.In this paper,Based on karst rocky desertification area of An Shun city which is located in the Yunnan-Guizhou plateau Zhen Ning buyi and miao autonomous county Shuang Longshan street agency Xin Fa village in typical small catchment(0.33 km2)as the research object,the grid method to uniform layout and collecting soil samples,and relying on the handheld weather instrument in the section of setting and sample area in micro valley regularly monitored temperature,wet bulb temperature,relative humidity,air pressure and other meteorological elements,using the geothermo-meter determination of ground temperature,integration of the surrounding mountain flood warning self-recording rain gauge measuring rainfall.Focuses on soil physical and chemical properties and micro valley climate heterogeneous characteristics,influence factors,using statistical methods to analyze different slope direction,slope,land use type,elevation of soil physical and chemical properties such as environment,climate characteristics and its influencing factors,discusses the typical karst soil resources in the micro occurrence and microclimate characteristics,occurrence of soil resources and its response mechanism,aimed at the recovery of karst rocky desertification governance,valley agricultural industrial structure adjustment to provide theoretical reference.The main results are as follows:1.The influence of various factors on soil reserves of surface and pore(fissure)is different,the interaction formed different soil occurrence characteristics,and the surface soil thickness was negatively correlated with altitude,vegetation coverage,rock bare rate and slope,which was negatively correlated with elevation and slope.Pore(fissure)gap soil reserves and fissure quantity,trace length,fissure opening degree,The depth of vertical surface is positively correlated with negative correlation with elevation and inclination angle.2.The soil moisture content of the surface and pore(fissure)gap decreases with the increase of soil depth,and the same soil layer increases with the slope,which is influenced by the surface vegetation.3.The soil PH value is higher than the hole(crack)gap,showing Arbor-uncultivated land >irrigated shrub and grassland,with the increase of soil layer increasing trend,the PH value of the reverse slope is increasing trend,and the PH value of the half sunny slope is generally higher than that of sunny and overcast slopes.4.The soil organic matter content of pore(fissure)gap soil is higher than that of surface soil,which decreases with the increase of soil depth,and shows the law of arbor,shrub and grass,and the fallow land and the negative slope,half sunny slopes.5.The total N,P and K of soil are mainly distributed in the soil surface,the surface soil content is higher than that of the pore(fissure)soil,which decreases with the deepening of the soil level,and the total P content shows the cultivated land of arbor and shrub,and the whole N and K shows as arable land,arbor > shrub and grassland.The direction of total K and P reverse slope decreases with the increase of slope position,and the direction of total p reverse slope increases.The soil physical and chemical properties were influenced by different slope position,slope direction and land use mode,but also affected by slope,vegetation cover,soil depth,rock bare rate and so on,the correlation between different topography factors and soil physical and chemical properties.6.At noon,the ground temperature is the highest,the same time segment with the depth of soil increase,the same soil depth is positively correlated with the ground temperature,the different slopes to the geothermal performance of sunny slopes,half sunny slopes,and land-class arable land and grassland,shrub and arbor.7.The temperature and air pressure change evenly,while relative humidity and wet bulb temperature change more intensely in the slope area,the altitude is negatively correlated with temperature,wet bulb temperature and air pressure,but it is positively correlated with relative humidity.The highest temperature of bare arable land,the lowest relative humidity.The temperature is negative slope,half sunny and sunny slopes,and sunny slopes are the most relative humidity,half sunny slopes are the lowest,and the barometric pressure is significantly higher than that in sunny slope and half sunny slopes.8.There is a response relationship between the improvement and improvement of microwatershed climate and the occurrence of soil resources.