The Research On Soil Properties Of Urban Green Space In Anning District Of Lanzhou City And Improving Method By Fertilizer

Due to severe environmental pollution and human disturbance,the structure and physicochemical properties of undisturbed soil are undermined,which make special properties of soil and different from the natural soil.Studying features of urban green area has some realistic meanings.Firstly,it can improve the fertility of the soil;Secondly,it is helpful in the maximum development and the ecology use of urban green space;Thirdly,it can help us study the features of landscape.Because of the influence of topographic features,climatic factors and human being,the soil in Lanzhou city is very complicated.So there are many problems which lies in the soil construction.In this paper,the physicochemical properties and soil fertility of green space in Anning District of Lanzhou City are detected and analysed and based on these,the EM bio organic fertilizers are used to improve the properties of the soil.The results of the study are :(1)The physical,chemical properties and nutrient level of soil in An Ningurban green space.The total porosity of urban greenings,the non-capillary porosity of soil,the average level of field capacity was respectively ranged from 37% to 42%,from 28%to 35% and 19.4% which is in a low level.The bulk density averaged1.43g/cm3,among the studied soil---67.1% of soil was more than 1.3g/cm3;the 14.2%of it was more than 1.5g/cm3.these indicated that the soil compaction phenomenon was significant;the average PH value of soil was 7.87 which showed a clear tendency to alkaline.The content of soil soluble salt varied from 3.0 g/ kg to 17g/kg which was far beyond the the optimum growth condition of green plants,which we called the soil salinization.the mean concentrations of available N averaged15.89g/kg which was relatively deficiency.the mean concentrations of available P was 59.63g/kg,rangedfrom 27 to 110g/kg.The ratio of soil N/P was between 1: 9 to7:10.the average value of soil available K was 134.95g/kg,the 80% studied soil was more than 120 g/kg,this indicated the soil was rich in potassium.(2)After applying EM bio-organic fertilizer on soil improvement of urban greenings.Compared with the farm manure and the chemical fertilize,the EM bio organic fertilizers can significantly improve the containing of organic matters of the soil;change the structure and physicochemical property of the soil.after applying the EM bio organic fertilizers,the organic matter was increased by 22%;Soil humus was82.5%;the soil cation exchange capacity increased 1.5 mg per 100 g.Comprehensive analysis showed that EM-fertilizer can effectively promote the transformation and utilization of soil nutrients;ease and improve the physical and chemical properties of soil;increase soil permeability aeration;alleviate and eliminate soil compaction phenomenon.Based on a comprehensive analysis of urban greenings in Anning,the improvement methods which related to the existing problems will be put forward and it may has some certain reference for further studying of greening in Anning district.