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In recent years, the emergence of the global warming problem countries are looking to reduce CO2 emissions, increase CO2 sequestration means. Soil carbon pool is the most active carbon pool in the surface of the Earth Sphere, the dynamic changes directly affect the concentration of greenhouse gases in the atmosphere. Agricultural soil carbon sequestration, especially paddy field soil carbon sequestration research has become one of the global hot spots. Jilin Qianguo Irrigation been developed since the 1950s, experienced a Puppet early days, the Bureau of Reclamation during the \organic carbon has also undergone some changes. In this context, to explore the potential and benefits of different development years of paddy field soil carbon sequestration, for Qianguo Irrigation coordinated development of the economy and the environment has important practical significance, but also for China's soil carbon sequestration and CO2 emission reduction list formulation provides a certain basis. In this study, the tutor the auspices of the National Natural Science Foundation of China under the support of the western Jilin 50 years LUCC research on soil organic carbon and drive mechanism, by means of remote sensing tools, interpreting QIANGUO 1989 to 2008, land use / cover change (LUCC ) through field sampling analysis of the vertical distribution of paddy field soil organic carbon accumulation rate. Based on this study the relationship between the density of the soil organic carbon content and changes in the amount of carbon sequestration potential and benefit estimate paddy soils of different development years to do with a brief analysis of developed external and paddy fields. Post-processing steps study area 1989,1996,2000,2004 and 2008 satellite images radiometric calibration, geometric correction, remote sensing information to strengthen and establish land use classification system, through supervision / unsupervised classification, and human-computer interaction interpret visual interpretation, inspection, interpret the results of high precision. Extraction of the area of ??the study area during the analysis of the area of ??change and spatial distribution. The results show that: the area of ??paddy fields from 1989 to 2008 showed a continuing growth trend. Which paddy field area from 1989 to 1996 the growth rate of faster growth rate slows from 1996 to 2000, from 2000 to 2004 have accelerated the growth rate from 2004 to 2008, the fastest growth. Second, site acquisition development 4a, 8a, 15a, 30a, 35a, 40a, 55a100cm depth paddy field soil samples to concentrated sulfuric acid - potassium dichromate determination of organic carbon content, based on analysis of each development years of cross-section vertical distribution characteristics of organic carbon and different development years of cross-sectional variation of SOC. The results show that: the paddy fields of organic carbon content and variability mainly to plow the soil plow layer soil (0-30cm), the plow soil organic carbon content decreased gradually with increasing the depth of the paddy fields, the development of effective soil organic carbon from the plow layer transfer. Different development years of paddy fields, organic carbon content for the sector for 30 years, the first 30 years of rapid growth, after 25 years of slow growth of stabilizing. Development than 55 years of paddy fields of soil organic carbon density values ??and the growth and development of 35 years of paddy fields, the difference was not significant. Again, a combination of the second soil survey and field test data, the irrigation area of ??paddy fields organic density changes in the amount and content of the relationship, and the amount of soil carbon density change 0:00 subtracting the amount of soil carbon soil carbon density of existing state estimate soil carbon sequestration potential. The results show that: about 30 to 35 years to develop irrigation area of ??paddy fields, soil organic carbon equilibrium, the potential for carbon sequestration value 204.84t/hm2. 1m depth paddy field with the development of the increase of years, developed four years of paddy fields, its carbon sequestration potential up to 79.29t/hm2. Initial organic carbon content is farther away from the saturation level, the faster the rate of carbon accumulation. With the growth of the organic carbon content of soil carbon will become increasingly difficult to maintain. Then, calculate the emission reductions trading price of price and quota trading price and tax rate in 2006, before Guo carbon sequestration benefits of paddy fields. The results show that: With the development of the increase of years, the carbon sequestration benefits of paddy field significantly improve. No matter what kind of price system, the paddy fields to develop carbon sequestration benefits that can be realized in 10 years to 10 billion. Finally, a brief analysis of the paddy fields developed external. Can see, despite the paddy field development there is potential for ecological destruction and environmental pollution, but as long as the proper management measures, these threats can be avoided. Its external economy is much larger than the not economy. The Paddy Fields for Qianguo Irrigation has very important economic sense and environmental sense.
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