Variations And Influencing Factors Of Soil Organic Carbon And Inorganic Carbon Of Paddy In Western Jilin Province Of Growing Stages

It has been a fact that, all the world has to face, the emissions of greenhouse gasessuch CO2, CH4lead to the global warming due to both artificial and natural factors. Aseries of environmental problems caused by global warming which has attractedattention from all the world will threat to the survival of mankind. As the sources andsinks of CO2terrestrial ecosystems affect the global carbon cycles and carbon balance.Soil carbon pool including organic carbon and inorganic carbon pool is the largestcarbon pool in terrestrial ecosystems, playing an important role in global climatechange.The existing studies on soil carbon pool concentrate on the forest and grasslandecosystems. There has many research findings of paddy ecosystems about the variationof soil organic carbon under different fertilizer application, moisture conditions duringgrowing stages. While there is few study on the variation of soil inorganic of growingstages. Therefore, it is will be more accurate and comprehensive when estimating thevariation soil total carbon pool of growing stages that soil inorganic carbon isconsidered.The saline-sodic and paddy soils of five different development periods from five to55years were collected form Qianguo irrigation area in Western Jilin Province locatedin Northeast China Transect (NECT) included in global change. Field monitoring andsimulation experiment were used to analyze the variations of soil total carbon, organiccarbon, inorganic carbon, pH, conductivity, hydrolyzable nitrogen, saccharase activity,polyphenoloxidase activity, catalase activity during growing stages. One-way ANOVA(factor analysis of variance) was used to ascertain development period’s impact on thenine factors. Multiple regression analysis was used to decide respectively whichinfluences soil total carbon, organic carbon, inorganic carbon greatest among chemicalfactors (pH, conductivity, hydrolyzable nitrogen) and biochemical factors (saccharaseactivity, polyphenoloxidase activity, catalase activity). Correlation analysis wasrespectively made between soil total carbon, organic carbon, inorganic carbon andchemical factors, biochemical factors. Principal component analysis and factor analysiswere used to study the main influencing factors of organic carbon. Multiple regressionanalysis and stepwise regression analysis were used to measure the impact of all factorson soil total carbon, organic carbon and inorganic carbon.The results show that development period is one of the main influencing factors on nine factors. The longer the development year is, the higher in soil total carbon, organiccarbon, hydrolyzable nitrogen, saccharase activity, polyphenoloxidase activity, catalaseactivity is and, the less inorganic carbon, pH, conductivity is. The nine factors changesfaster at first than later, even several of them fluctuated. During growing stages soiltotal carbon, organic carbon show variations of “decrease-decrease-increase-decrease”.Soil pH, conductivity, hydrolyzable nitrogen show variations of “decrease-decrease-decrease-increase”. Saccharase activity and catalase activity show variations of“decrease-decrease-increase-increase”. Polyphenoloxidase activity shows variations of“decrease-increase-decrease-increase”. Hydrolyzable nitrogen and catalase activityaffect soil total carbon, organic carbon, inorganic carbon greatest respectively amongchemical factors and biochemical factors. By comprehensive analysis of all factors,hydrolyzable nitrogen, conductivity and polyphenol oxidase impact soil organic greatest.Hydrolyzable nitrogen, conductivity and saccharase impact soil inorganic carbongreatest. Conductivity, catalase activity and hydrolyzable nitrogen impact soil totalcarbon greatest. The results provide basic data for estimating regional soil carbonstorage of paddy field ecosystem, and reference to the development of saline-sodic soilsand scientific management of paddy fields.The studies provide basic example of smallscale area for the study of global carbon cycle.