Study On Soil Quality Evaluation Of Land Development And Consolidation Region Based On Quantitative Remote Sensing

The policy of land developing and consolidating in our co-untry is a strategic decision made by the CPC Central Committee under the state council based on the current level of economic development of China. Cultivated land protection and improvement of soil quality is the important aspect. With the development of the different levels of land developing and consolidating project, evaluations for these projects, especially the soil quality quantitative evaluations after consolidating is becoming more and more important. Evaluations for the soil quality after land developing and consolidating are very few. There are two reasons. On is the soil quality evaluation standards having not unified, on the other hand, soil quality evaluation takes a lot of manual labor and time, material and financial resources, so it is very difficulty and few people do the job. Remote sensing technology has been used successfully in many aspects such as the soil organic matter, soil moisture, land use change monitoring and vegetation index monitoring and so on for the advantages of rapid, accurate, economic, and can be periodic observation, provides a new train of thought and technical support for soil quality evaluation of land development and consolidation.Based on the land development projects acceptance regulation and the second soil survey technical regulation of China, the idea is put forward innovatively for the first time that using Remote Sensing technology to establish soil quality evaluation index system including soil physical, chemical indicators, biological indicators for the land development and consolidation area, and extracting the soil organic matter, the surface temperature, evaporation, soil moisture, soil erosion, vegetation coverage index and so on. This theory and technology support for the soil quality evaluation is provided after land consolidation. At the same time, it is a new research field to using the remote sensing technology in soil quality evaluation after land development and consolidation, it will also enrich the land consolidation theory of China, promoting the formation of land consolidation evaluation theoretical system, promoting the development of digital agriculture and precision agricultureUsing the SPOT, TM/ETM multi-spectrum image as data sources for the first time by collecting soil samples from field to do indoor analysis, determining the field soil sample spectrum curve at the same time, to analysis the spectral curve and build up multispectral remote sensing image and quantitative polynomial and the BP neural network inversion model of soil organic matter. Model inversion accuracy is high, the inversion results show that the soil organic matter content increased obviously after land consolidation, the soil fertility improved and the distribution is uniform, the inversion results consistent with the sample determination results, land leveling effect is remarkable. Validation for the first time in Hunan hilly region of soil organic matter composition such as reflectivity, image sample points and the measured sample points reflectivity has the corresponding fitting relationship, especially in the red light and near infrared band best fitting effect, fitting degree reaches more than0.8.Temperature and evaporation are closely related with soil quality. Using SEBAL model and TM/ETM remote sensing data for the surface temperature and evaporation in spatial distribution in development and consolidation project area of Hunan hilly land has carried on the exploration. The results show that the SEBAL model can map the project area soil temperature profile or evaporation reasonably and effectively in the region and the inversion results is real and effective. It is the first time that inversing the temperature and evaporation with soil quality of land developing and consolidating.Vegetation index and soil erosion degree are the most important indicators of the soil quality. Object-oriented technology has been used to identify the types of land use remote sensing in Hunan's hilly area of land development and consolidation project area, the algorithm research of TM images extracting the vegetation index is been put forward, interpreting the vegetation index in the study area, using the3S technology to analyzing the dynamic variation of land using, soil erosion and the relationship between the changes of soil erosion and soil quality. The results show that after the land development and consolidation, vegetation coverage is increased, soil erosion is greatly improved.Two land consolidation development experimental regions are Xiangtan county of Hunan province Yang Jiaqiao township and Changde HanShou county NanTai village, by acquiring remote sensing images and field soil samples collected before and after land consolidation, the measured spectral data, extracting the soil quality evaluation index information of remote sensing for the first time in Hunan hilly region of soil organic matter content, surface temperature, evaporation, soil moisture and soil erosion, vegetation index etc. This paper Classified and Weighted the soil quality evaluation index of remote sensing with comprehensive index, evaluated and analyzed the soil quality of the study region used the soil quality evaluation index system. The innovation of theory and technology is provided, the evaluation results is in line with the actual.It will be a development trend of soil quality evaluation in the land development and consolidation project.