Effects Of Conservation Tillage On Soil Organic Carbon And Active Carbon Fraction On Long Zhong Loess Plateau Region

Soil organic carbon pool is the largest of terrestrial ecosystem carbon pool, itsreserves change can not only directly affect the emissions of carbon into theatmosphere can also affect the land vegetation nutrient supply. In agriculturalproduction, the low level of agricultural production, including removal of residue,burning, and lack of water and soil conservation measures, is in the history of themain cause of soil organic carbon reserves to reduce. At present, the domestic andforeign scholars study of conservation tillage measures mainly concentrated in asingle protective treatment on the influence of soil total organic carbon, or differentconservation tillage treatment affect the components of an activated carbon, at thesame time, the lack of soil organic carbon composition changing rule in differentgrowth period, and a variety of conservation tillage treatment on research on theeffects of soil active organic carbon components. Through a long-term experiment indingxi, the three reproductive period, four kinds of protective treatment, namely,(Conventional tillage (T), No-till with straw mulch (NTS), No-till without strawmulch (NT), Conventional tillage with straw incorporated (TS) four protectivetreatment), at the same time, combining with the spring wheat/peas (W-P-W) andpea/spring wheat (P-W-P) two kinds of rotation sequences, on Soil organic carbon(SOC) and soil carbon composition were studied. Components of easy oxidation ofactivated carbon mainly include Soil organic carbon (ROOC), Light fraction organiccarbon (LFOC), Microbial biomass carbon (MBC). The following conclusions:1. In2012, with rotation in two kinds of order, of0-5,5-10,10-30cm soil layersoil SOC content determination found that in the three layers of soil SOC contentchange trend are characterized by: NTS and TS treatment compared with T. NTSlong-term processing of soil organic carbon storage effect is obvious; Under varioustreatments, Soil organic carbon with the deepening of the soil layer of continuous decline phenomenon.2. Three of the different cultivation measures of soil, soil ROOC content isshown as: W-P-W under the rotation order sorting for NTS>NT>TS>T and P-W-Protation order of NT>TS>NTS>T, conservation tillage measures is superior toconventional tillage.3. In the whole growth period, the T handle soil MBC reduces amplitude wassignificantly higher under NT, NTS, treated with no-till soil, changes in the MBCminimum amplitude, late harvest is significantly higher than soil MBC T handle.4. Under different rotation,0-5,5-10,10-30cm soil layer, the determination ofquantity of soil LFOC found that soil LFOC content0-30cm depth of vertical changetrend is gradually decline, NTS and TS, NT, T handle.5. Components with soil depth change in Soil organic carbon in the process ofNTS of TS, NT, T handle content in different soil layer were increased significantly.NTS of ST, NT, T deal with ROOC in soil, with the deepening of the soil MBC,LFOC content reduce quantity significantly reduced.