A Study On Potential And Benefits Of Carbon Sequestration Of Paddy Soils At Qianguo Irrigation Area

Recently, experts from the world are looking for methods to reduce CO2 and increase CO2 sequestration to solve global warming problems. Soil carbon pool is the most active surface of the Earth's carbon cycle library, and it can impact on the dynamic changes in atmospheric concentrations of greenhouse gases directly. Therefore, agricultural soil carbon sequestration, especially in paddy soil carbon sequestration research is becoming a global hot topic. Jilin Qianguo Irrigation is developed in the 50s of last century, and it has experienced the Puppet Government, the founding of the Bureau of Reclamation, the "Cultural Revolution" period, and reform and open up period. The development of paddy growing is more than 60 years, and food production is increased year by year, so the soil organic carbon must be occurred some changes. In this context, a study on potential and benefits of paddy soil at Qianguo Irrigation has important practical significance for coordinated development of economy and environment. And this study also provide a basis for the development of soil carbon sequestration and CO2 emissions inventory.The study is supported by the National Natural Science Foundation of China-"50 years in Western Jilin Province LUCC on soil organic carbon and its driving mechanism of", using "3S" technology to interpret land use/cover change (LUCC) situation, and analyzing longitudinal distribution of organic carbon accumulation rate through the paddy field soil samples. Looking for the the relationship between the variation and content on organic carbon density of paddy soils, and estimating the potential and benefits of soil carbon sequestration in different development years. And then analyzing the externalities of paddy field with a brief.First, the satellite images of study area in 1989,1996,2000,2004 and 2008 were changed by radiometric calibration, geometric correction to enhance remote sensing information processing, through supervision/non-supervised classification to create a land use classification system, and human-computer interaction interpretation of visual interpretation to interpret the results accuracy. Extraction of the study area the size of each period to analyze the size and spatial distribution. The results showed: paddy area from 1989 to 2008 there was a consistent growth trend. From 1989 to 1996, the paddy field area was grew rapidly; From 1996 to 2000 that was grew slowly; From 2000 to 2004 that was grew accelerate; From 2004 and 2008 that was grew the fastest.Secondly, the study of the field collected 4a,8a,15a,30a,35a,40a,55alm depth of paddy field soil samples to potassium dichromate-sulfuric acid method of organic carbon content of the test, on the basis of the development to research the vertical distribution of carbon and different development characteristics of life profile changes in SOC. The results showed that:the variability of organic carbon content of paddy fields is mainly in the plow layer soil (0-30cm), plow pan depth of soil organic carbon content decreases with deepness increasing. Different organic carbon content in paddy field development grow rapidly in the first 30 years, and grow slowly in the late of 25 years. The growth rate of soil organic carbon density of paddy fields of 55 years was not significant,compared with the development of paddy fields of 35 years.Thirdly, combined with the second soil survey and field test data, researching the relationship between the variation and content of organic carbon density, and estimating the potential soil carbon sequestration. The results showed that:1m depth of paddy soil organic carbon sequestration potential decreased with the increasing number of years. Paddy soil developed for 4 years can reach to 79.29t/hm2 of carbon sequestration potential, however, soils that developed for 30 to 35 years has reach to the balance value of carbon sequestration, the value is 204.84t/hm2.Fourthly, calculate the benefits of carbon sequestration of paddy field at Qianguo, in the price of emission reductions, transaction and the rate of quota trading. The results showed that:With the increase of years of development, carbon sequestration benefits of paddy field increased significantly. Whatever the price system, the paddy field development can be realized to ten million carbon sequestration benefits within 10 years.Finally, take a brief analysis of development externalities of paddy field. Despite the existence of developing paddy fields may lead to ecological destruction and environmental pollution, while as long as using management properly, these threats can be avoided. The external economy is much larger than the external diseconomy. Qianguo irrigated paddy field development has a very important economic significance and environmental significance.