Effect Of Farming Practice Types On Soil Organic Carbon On Slope Field In Red Soil Area

In the slope cropland, the soil structure is greatly damaged and the soil quality islargely decreased, thereby leading to loss of soil carbon. Thus, improved types of farmingpractices in the slope cropland will be beneficial for carbon sequestration, soil fertility, soilquality and soil and water conservation. In this thesis, soil hydro-physical properties, soilorganic carbon, soil aggregate organic carbon and soil active organic carbon were studiedin a slope cropland plot (control) and four types of farming practices, i.e. dry terrace landplot, tea garden plot, abandoned land plot and artificial grassland plot in Jiangxi Institute ofRed Soil. This study was designed to better understand the mechanism of types of farmingpractices on soil carbon sequestration, aiming to provide data for improving soil fertilityand making policies on farming practices in slope cropland, rational allocation of land useand development of low carbon economy.The results are as follows:(1) The types of farming practices have differential effects on soil hydro-physicalcharacteristics, with the best in artificial grassland and worst in abandoned land.(2)Soil organic carbon and soil organic carbon stocks were greater in all of the fourtypes of farming practices, relative to the control., Relative to abandoned land in the soilprofile of0-60cm, the soil carbon content were increased by21.18%in artificial grassland,57.20%in tea garden plot, respectively. The results suggest that garden plot was the bestfor soil carbon, followed by artificial grassland.(3)The proportion of>2mm soil particle from dry sieve was the largest, rangingbetween40.55and75.18%, while that of <0.05mm soil particle from wet sieve was thelargest. For>0.25mm of the water stability aggregate, the damage rate was lower in thetreatment plots (28.58%) than in the slope cropland (47.17~49.05%). These results indicatethat dry sieve method was better for aggregate organic carbon content than wet sievemethod. Farming practice treatments significantly increased the storage of soilmacroaggregate organic carbon, promoting the recovery of soil organic matter,contributing to formation of aggregates and improving stability of reunion.(4)Types of farming practices had some effects on soil active organic carbon. The soilROC content fell within the range of1.97~3.22g/kg. However, the degree of soil DOCchanges was the biggest in the control plot (23.67mg/kg), followed by tea garden plot(14.43mg/kg) and lowest in artificial grass plot (2.09mg/kg). The soil MBC content ofartificial grass was improved to a greater degree, achieving to73.15mg/kg.(5)Through the level of comprehensive benefits on soil organic carbon fertility, whichanalysis soil hydro-physical characteristics and organic carbon sequestration benefitsevaluation in red soil area. The comprehensive benefits of soil active organic carbonfertility were the highest in tea garden plot, i.e.5.74%higher than abandoned land,10.88% higher than slope cropland,7.97%higher than artificial grassland and11.63%higher thandry terrace land, respectively.In conclusion, soil organic carbon concentration, soil fertility and quality were greatlyimproved by farming practice treatments, thereby enhancing the level of fertility and fixedsoil carbon and contributing to the sustainable of land use in red soil area.