Response Of Soil Physicochemical Properties To Different Vegetation Restoration In The Loess Hilly Region Of Southern Ningxia

In order to give scientific support to reasonable selection and control of vegetation,and ecological functions of the soil.An experiment was arranged with six ecological restoration processes,ie,Prunus sibirica,Prunus davidiana,Hippophae rhamnoides,Mixed forest,Alfalfa and Wasteland,in the Zhongzhuang small watershed of Baiyang Town,Pengyang County,Ningxia.Six types of typical vegetation types were selected,from a total of 1 m soil depth was obtained in five layers,with 3 replicates.The method of combining the circular knife method and laboratory analysis was used to analyze the physicochemical properties of different vegetation soils to evaluate the physical and chemical properties of the soil during the ecological restoration process in this area.The results are as follows:(1)The order of the soil bulk density of each vegetation was Alfalfa>Wasteland>Prunus davidiana= Hippophae rhamnoides>Prunus sibirica>Mixed forest;the soil water saturation capacity and soil capillary water holding capacity were basically the same as the soil bulk density,and the field water capacity was more than All of them are different;the order of total soil pores is Prunus sibirica>Mixed forest>Alfalfa>Prunus davidiana>Hippophae rhamnoides>Wasteland.The non-capillary porosity change law is basically the opposite to the total porosity.The capillary pore change is similar to the total porosity.The soil bulk density of the forest land is smaller than that of the Alfalfa and the Wasteland.The water holding capacity is greater than that of the Alfalfa and the wasteland,and the ventilation of the soil is good.(2)The ratio of water-stable macroaggregates,MWD,GMD,and D of Mixed forest land were larger than those of Prunus sibirica,Prunus davidiana,Hippophae rhamnoides.Prunus sibirica,Prunus davidiana,Hippophae rhamnoides was greater than that of Alfalfa.The value of each index of Wasteland was the smallest,indicating soil resistance of Mixed forest land.Erosion ability is the strongest,Alfalfa the worst,and the Wasteland is the worst.(3)Soil organic matter,total phosphorus,total potassium,and available potassium were relatively better in the Alfalfa,but total nitrogen and available nitrogen were more in the Mixed forest and the Prunus sibirica.The difference in total salt content between the various vegetations was small,indicating that the soil nutrients in the Alfalfa were relatively It is better,followed by Mixed forests and Prunus sibirica.(4)When the depth of soil is more than 60 cm,the characteristics of vegetation types are no significantly different(p<0.05).