Study Of Interpreting Soil Electrical Conductivity Based On EM38-MK2 In A Cotton Field With Plastic Film Covering

Soil salinization is the comprehensive effect of various natural factors and human activities factors, soil soluble salt accumulation on the soil surface phenomenon. Soil salinization is the physical and chemical properties of soil deterioration, weaken and destroy the land productivity, reduced effectiveness of soil nutrients, causing plants "physiological drought", leading to apoptosis, sustainable development will be a direct threat to the ecological, economic and social consequences. With the global population increase, the growing demand for food, the farmland has become the key to human survival, however, soil salinization hazards as one of the degradation in many countries of the world are facing the most serious land, severely restrict the agricultural productivity, and has now become a global serious ecological problems. China in the "modern agricultural development planning(2011-2015 years)" proposed to "strengthen the agricultural science and technology in agriculture", to "promote the application of precise operation", "remote sensing monitoring, disaster warning" of the objectives and tasks. Thus, the problem of soil salinization is one of the ecological problems in arid and semi-arid area of social and economic development cannot be ignored, effectively carry out the related research of oasis agricultural soil salinization monitoring and early warning, results of technology will be applied to the area of development of the truth, and extended to the practice of agricultural development is imminent.1)Through EM38-MK2 conductivity meter collected a sample of 217 soil samples, to use of Geo-statistics knowledge combined with Arc GIS software to analysis distribution of detailed in the cotton fields of conductivity, the plots in the north central regional apparent highest conductivity to the other direction decreases. Based on various points of different depth of soil sampling, through the experiment analysis EC1:5 data is obtained, and then to analysis the sampling of soil conductivity distribution, to the first class soil electrical conductivity profile, its mean and median showed decreased first and then increased trend. The characteristics change due to irrigation so that salt in soil profile overall downward leaching, resulting in salt gathered below 40 cm, makes the soil is in a state of desalination. The electrical conductivity of the second soil profiles showed the same trend but the degree of the change was weak, the upper level was slightly salinization, and the bottom was moderate salinization degree. The third types of soil profiles with the fourth types of soil profiles showed a relatively uniform trend, in mild salinization and non saline state.2)In the use of EM38-MK2 conductivity meter collection points of different height of vertical modes of apparent electrical conductivity data, on the basis of previous studies, constructs the film covering Miao Tian experience the interpretation model for soil electrical conductivity. And the use of linear physical principle of electromagnetism response model of different height of the apparent conductivity of the direct conversion based on the data obtained, the conductivity of the soil profile. Soil electrical conductivity data and the two methods are analyzed and compared.