Effect Of Organic Farming On N₂O And CO₂ Emissions And Warming Potential In Saline Soil

Organic farming can reduce greenhouse gas emissions, but the lack of relevant in saline soil organic planting how can on greenhouse gases emission reduction effect.This experiment in daqing saline-alkali land for many years organic farming is the base of field location test, the selected crops are mainly soybeans and corn, the organic farming is compared with conventional farming of conditions near the same, using field location test, the test characteristics of soil carbon and nitrogen and greenhouse gas(CO₂ and N2 O emissions targets, the organic farming under the condition of the experiment on greenhouse gas emissions reduction effect, for the scientific research of saline soil upland soil in greenhouse gas emissions（CO₂ and N₂O） provides the basis for evaluating the environmental benefits of data.The results are as follows:（1）Organic farming land, soil organic carbon, organic nitrogen content than the conventional planting land has increased significantly.SOC, TN, nitrate nitrogen, ammonium nitrogen are show the obvious effect of storage of carbon, nitrogen, and strong storage capacity.Along with the increasing length of organic farming, soil SOC, TN has a certain degree, and a significant difference（p < 0.05）, shows that organic farming is fixed number of year of saline soil has great effect on SOC and TN.At the same time, all the year round for the region to organic farming, organic fertilizer make the SOCD of saline soil, SND have to ascend, and SOCD and fixed number of year of SND in different organic farming also have some significant differences（p< 0.05）.（2）During the growing period, plant corn, beans on saline soil of soil N2 O emission flux is similar to the changing rule of the CO₂ emission flux, has obvious seasonal variation characteristics.At the same time, dynamic rule of seasonal change of N2 O and CO₂ emission to the growth of the corn, soybeans the seasonal change of dynamic has certain synchronicity, The N2 O emission peak concentration in the later period of crop growth, and the emission peak in the middle of crop growth, namely the most robust stage of reproductive growth.（3）The organic soil CO₂ and N₂O emission flux is lower than the conventionally grown on average, organic farming is the average CO₂ and N₂O emission flux and conventional planting significant differences（p < 0.05） and soybean fields average soil CO₂ and N₂O emission flux is lower than the corn field.With the increase of organic farming is fixed number of year, corn and soybean fields soil CO₂ emission flux is a trend of increase.（4）Organic farming has certain influence on greenhouse gas warming potential, and conventional cultivation has obvious difference（p < 0.05）, the whole, organic farming iseffectively reduce the greenhouse gas warming potential.In the observation of two years corn processing warming potential size compared to conventionally grown greater than organic farming,and the rising along with the increasing length of organic farming.Soybean processing warming potential size is in addition to the observation of organic farming in 2014 emissions are slightly different, other are the same as the corn processing.In conclusion, organic farming has good improvement effect to saline soil upland soil,increase the soil organic carbon, soil total nitrogen, nitrate nitrogen, ammonium nitrogen content,and have obvious differences between organic and conventional cultivation, organic farming has significant difference;Organic farming SOCD, SND have significant difference, and a significant differences between the groups.Organic planting corn, soybeans, CO₂ and N2 O emissions than conventional planting corn, soybean, along with the increasing length of organic farming, corn,soybeans, CO₂ and N₂O emissions have increased trend, organic farming is to achieve a certain fixed number of year of planting, their greenhouse gas emissions would increase.Organic farming is increasing potential is lower than conventional planting, prove that organic farming is to reduce the dry field is probably the greenhouse gas emissions.