不同土地利用方式下土壤温度与土壤水分对黑土N2O排放的影响  

Impact of Soil Temperature and Moisture on Soil N_2O Emission from Mollisols Under Different Land-use Types

作　　者：石洪艾[1,2] 李禄军[1] 尤孟阳[1] 丁娇[3,2] 王帅[4] 韩晓增[1] 

机构地区：[1]中国科学院东北地理与农业生态研究所 黑土区农业生态重点实验室,哈尔滨150081 [2]东北农业大学资源与环境学院,哈尔滨150030 [3]中国科学院东北地理与农业生态研究所黑土区农业生态重点实验室,哈尔滨150081 [4]黑龙江省八五二农场,黑龙江双鸭山155620

出　　处：《农业环境科学学报》2013年第11期2286-2292,共7页Journal of Agro-Environment Science

基　　金：中国科学院黑土区农业生态重点实验室基金(2011ZKHT-01);中国科学院战略性科技先导专项(XDA05050501);联合国开发计划署(UNDP)项目(CPR/06/209-04,08)

摘　　要：采用静态箱-气象色谱法,对黑土区3种不同土地利用方式(草地、裸地和农田)下土壤氧化亚氮(N2O)的排放特征及其与土壤温度和土壤水分的关系进行研究。结果显示:试验监测期间(2011年5月27日—9月30日),不同土地利用方式下,土壤N2O累积排放量分别为草地52.08 mg N·m-2、裸地64.43 mg N·m-2、农田70.16 mg N·m-2,农田土壤N2O累积排放量比草地和裸地分别高出35%和9%,草地、裸地和农田的N2O平均排放通量分别为16.56、20.36、21.44μg N·m-2·h-1。草地和裸地中,土壤N2O排放通量与土壤温度和土壤水分(充水孔隙度,WFPS)相关性均不显著,但在农田中,土壤N2O排放通量与土壤温度(5 cm和10 cm)和土壤水分(5 cm)均呈显著正相关(P<0.05)。另外,土壤N2O累积排放量与土壤硝态氮和矿质氮含量均呈正相关关系。研究表明,黑土草地开垦可促进土壤N2O的排放,且不同土地利用方式下土壤N2O排放的主要影响因子不同。Using static closed chamber and gas chromatography techniques, we examined the patterns of soil nitrous oxide（N2O） emission from Mollisols in Northeast China as affected by changes of land use（grassland, bare land, and cropland）, and related soil N2O fluxes to soil temperature and moisture. The results showed that, during the monitoring period（from May 27 to September 30, 2011 ）, the cumulative N2O emission was higher in cropland（ 70.16 mg N· m^-2） than those in grassland（52.08 mg N· m-2） and bare land（ 64.43 mg N· m-2） by 35% and 9%, respectively. The mean N20 emission fluxes in grassland, bare land, and cropland were 16.56 μgN·m^-2·h^-1, 20.36 μgN·m^-2·h^-1v, and 21.44μgN·m^-2·h^-1, respectively. In grassland and bare land, there were no significant correlations between soil N2O flux and soil tempera- ture and soil moisture （water-filled pore space ）, whereas in cropland, soil N2O flux was significantly correlated with soil temperature （5 cm, 10 cm） and soil moisture（5 cm）（all P〈0.05 ）. In addition, soil cumulative N2O emissions were positively correlated with soil nitrate nitrogen and inorganic nitrogen content. Our results suggest that conversion of grassland to cropland in Mollisols can promote soil N2O emission, and the main driving factors for soil N2O emission vary under different land uses.

关 键 词：充水孔隙度(WFPS) 排放通量 氧化亚氮 矿质氮 

分 类 号：X511[环境科学与工程—环境工程]