摘要
为了确定不同森林经营利用方式(原始林、皆伐林、渐伐林)及不同生境(有林地、无林地、湿地)对于森林土壤-大气主要温室气体通量的影响,于2013年生长盛季(7─8月),在内蒙古大兴安岭兴安落叶松(Larix gmelinii)林区选取了16块样地,采用静态箱/气相色谱法进行了土壤-大气温室气体通量的原位观测。气体监测的同时,测定了土壤湿度和各层土壤温度以及各样地土壤的物理、化学性质。实验结果表明:大兴安岭兴安落叶松林区生长盛季CH4通量平均值为C(-133.6±62.3)μg·m-2·h-1。沼泽湿地(PD2和PD7)CH4表现为释放,CH4通量平均值为C(130.0±41.0)μg·m-2·h-1,其它14个样地土壤CH4为吸收,吸收通量变化范围为C(-242.0^-42.6)μg·m-2·h-1,变异系数为47%。所有样地CO2的地-气通量变化范围是C(94.9~1164.0)μg·m-2·h-1,平均值为C(671.3±324.3)μg·m-2·h-1,变异系数是48%。所有样地N2O通量的范围是N(1.2~21.6)μg·m-2·h-1,平均值为N(7.3±6.1)μg·m-2·h-1,变异系数为84%。通过数据分析显示,大兴安岭林区生长盛季不同经营方式及不同生境对森林土壤-大气CH4、CO2、N2O通量均无显著相关性。CH4通量与土壤各层温度及各层湿度并未发现有显著相关性,仅显示CH4通量与土壤有机质(SOC)呈正相关关系、土壤全氮(TN)呈负相关关系;CO2通量与土壤5 cm处温度显著相关(P=0.042 3),与土壤0 cm及10 cm处温度无显著相关性,CO2通量与土壤各层温度呈正相关关系,与腐殖质层、0~10 cm以及10~20 cm土壤湿度呈负相关关系,与SOC、TN呈负相关关系;N2O通量与土壤各层温度、湿度及SOC均呈正相关关系,与TN呈负相关关系。
In order to identify the effects of different forest management (virgin forest, clear-cutting forest and successive cutting forest) and topographic conditions (forestland, non-forest land, marshland) on soil-atmosphere exchange of greenhouse gases, nitrous oxide (N2O), methane (CH4) and carbon dioxide (CO2) fluxes of soil cores from 16 representative sites were determined in situ of Larix gmelinii Forest of Inner Mongolia, and the relative soil properties such as soil moisture, soil temperature in each soil layer was measured simultaneously. The soil average CH4fluxes in the thriving growing season was (-133.6±62.3)μg·m^-2·h^-1.Strong CH4 emission was found in two wetlands (PD2 and PD7), whereas CH4 showed soil sink in other 14 sample sites, with a range from -242.0 to -42.6μg·m^-2·h^-1 and CV of 47%.CO2 emissions from all sites ranged from 94.9 to 1164.0μg C·m^-2·h^-1, with a mean value of (671.3±324.3)μg C·m^-2·h^-1 and a CV of 48%. Soil N2O emissions across all of the investigated sites ranged from 1.2 to 21.6μg N·m^-2·h^-1, with a mean of (7.3±6.1)μg N·m^-2·h^-1 and a CV of 84%. Different forest management and different habitats have no obvious effects on soil N2O, CH4 and CO2 fluxes. There is no correlation was found between soil CH4 flux and soil temperature and soil moisture at each depths, but CH4 flux is positively correlated with soc, but negatively with soil TN. CO2 flux is negatively related with soil moisture in each layer, and positively correlated with soil temperature at 5 cm depth(P=0.0423). Positive correlation was found between N2O flux and soil moisture, temperature, and SOC, but negatively with soil TN.
出处
《生态环境学报》
CSCD
北大核心
2015年第3期378-386,共9页
Ecology and Environmental Sciences
基金
国家自然科学基金项目(31160117
31260119)