吉林西部盐碱水田区全球变暖潜势研究

为了探讨吉林西部土地整理工程对区域全暖所做贡献，基于实测的水田土壤温室气体数据，进行区域温室气体排放分析，为进一步评估水田开发对全球变暖的影响提供科学依据。以吉林省西部盐碱水田区为研究对象，将野外调查采样和小区试验相结合，采集了水田的0-30 cm表层土壤样品带回进行小区实验。在小区内挖取100 cm×100 cm×50 cm的坑，在土坑底部铺设塑料布后，将从采样点带回的土壤填进坑内灌水，种植水稻，6块样地分别为不同开发年限，其处置模式与前郭当地的水肥管理相同，样地周围挖掘了排水渠。通过静态箱-气相色谱法监测水稻生长期土壤所释放的温室气体 CH4，N2O 和CO2，计算水稻不同生长时期温室气体排放量及贡献率，估算研究区的区域变暖潜势（GWP），结合30年水田面积变化加权法分析温室气体GWP贡献率。结果表明：水田生长期温室气体排放总量（以CO2气体计）随着开发年限的增加呈递增趋势，水田开发过程中CO2、CH4和N2O各时期温室气体排放的贡献率都有一定变化，CO2气体排放贡献率占主导地位在80%左右，CH4的贡献率16.69%-20.39%，是N2O的14-22倍，水田CH4气体的排放对研究区综合温室效应有较大贡献，水田开发初期N2O气体贡献率较成熟水田相比较高。在水稻生长旺盛期CO2气体贡献率下降明显，CH4气体贡献率显著升高，N2O气体贡献率变化不大，在返青期和成熟期CH4和N2O 2种气体贡献率均较小，其中，除成熟期外新开发水田的CH4气体贡献率均高于成熟水田，在水稻生长发育较快速的分蘖期、拔节孕穗期和抽穗开花期，CO2气体贡献率下降且降幅明显，该阶段CH4气体对温室效应的贡献比重加大，远高于N2O气体。在水稻成熟期，3种温室气体的贡献率与其他时期相比发生较大变化，CH4比 N2O 略有优势，CO2所占比例恢复至95%。?

Estimation of Global Warming Potential in the Saline-alkali Paddy Fields of Western Jilin

In order to explore the western Jilin land consolidation project＇s contribution to regional-wide warming, based on the measured data of paddy soil greenhouse gases, the analysis of regional greenhouse gas emissions, a scientific basis for assessing the impact of paddy development on global warming had been provided. With the method of combining field sampling and region experiments, taking saline-alkali paddy field of Jilin province as an investigation object, of 0-30 cm surface soil samples of paddy were collected back to the experiments field. Pits with the size of 100 cm × 100 cm × 50 cm were digged in the field, after laying plastic sheeting at the bottom of the pits, the soil taking back from the sampling points were filled into the pits, watering, planting rice. Six plots were filled with different developed age soil, their disposal model was the same as QianGuo＇s local water and fertilizer management, drainage.was digged around the plots To research the greenhouse gas emission and contribution in the paddy, estimate GWP in the area, CH4, CO2 and N2O that released by soil during rice growth period were monitored by Static box - gas chromatography. combine The greenhouse gas GWP contribution was analysised combined with thirty years paddy area change. The results show that different development age total value greenhouse gas emissions （CO2-eqv） during paddy growing appeared an increasing trend, in the development process paddy CO2, CH4 and N2O emissions of greenhouse gases contribution rate for each period has a certain change, CO2 emissions contribution rate is dominant about 80%, CH4 contribution rate 16.69%-20.39%, is N2O 14 to 22 times, indicating CH4 emissions have a great comprehensive contribution on study area .In early paddy, N2O has higher contribution rate compared to mature paddy. In the rice growing vigorous period, CO2 contribution rate was decreased obviously, CH4 contribution rate was increased significantly, N2O contribution rate changed little. CH4 and N2O contribution rate is sma