北亚热带红壤丘陵区3种土地利用方式下CH_4通量及其影响因素  

CH_4 Fluxes and Its Influence Factors under Three Land Use Type in the Hilly Red Soil Region of Northern Subtropical, China

作　　者：田亚男[1] 聂文婷[2] 张水清[1,3] Muhammad Shaaban 吕昭琪 殷欣[1] 林杉[1] 

机构地区：[1]华中农业大学资源与环境学院//农业部长江中下游耕地保育重点实验室,湖北武汉430070 [2]长江科学院水土保持研究所,湖北武汉430010 [3]河南省农业科学院植物营养与资源环境研究所,河南郑州450002

出　　处：《生态环境学报》2015年第9期1434-1440,共7页Ecology and Environmental Sciences

基　　金：国家自然科学基金项目(41201255;41171212);中央高校基本科研业务费专项资金资助项目(2013PY114);国家重点基础研究发展计划项目(2012CB417106);公益性行业(农业)科研专项经费项目(201203030-5)

摘　　要：以北亚热带红壤丘陵区林地、茶园、菜地为对象,采用静态箱-气相色谱法,对3种土地利用方式下CH4通量进行了研究,同时测定了土壤温度、含水量和无机氮含量。旨在探索不同土地利用方式下CH4"源"和"汇"的功能,对评估不同土地利用方式对全球气候变化的贡献具有重要意义。结果表明,不同土地利用方式下土壤甲烷平均通量有显著差异,分别为:林地-15.44μg·m-2·h-1,茶园-1.49μg·m-2·h-1,菜地7.11μg·m-2·h-1;菜地土壤甲烷平均通量最高,茶园其次,林地最低,CH4年累积通量分别为0.52、-0.31和-1.46 kg·hm-2,菜地土壤以排放CH4为主,而茶园和林地土壤是CH4的汇。茶园和菜地土壤CH4通量呈一定的季节性变化,春、秋季CH4通量较高。林地CH4吸收通量与土壤湿度呈显著的负相关关系(P<0.05),且当土壤湿度(WFPS)高于70%时,林地土壤才以排放CH4为主;而茶园和菜地土壤CH4吸收通量与土壤含水量无显著相关关系。土壤CH4通量与土壤温度之间未呈显著的相关关系。不同土地利用方式下土壤CH4排放通量与铵态氮含量呈显著的负相关关系(P<0.05),而与硝态氮含量未呈显著的相关性。CH4 fluxes from soil under three land use types (woodland, tea field and vegetable field) were measured with static chamber-GC techniques; we also detected soil temperature, moisture and mineral nitrogen concentrations at the same time of gas sampling in the hilly red soil region of north subtropics. The purpose of the study is to explore the function of CH4 “source”and"sink"in different land use patterns, is of much importance to evaluate the contribution of different land use patterns to the global climate change. Our results showed that land use types had great influence on mean CH4 fluxes, vegetable field, tea field and woodland were 7.11,-1.49,-15.44μg·m-2·h-1, respectively, the highest fluxes from vegetable field, the second higher from tea field, while lowest values being observed from woodland. The annual cumulative CH4 fluxes were 0.52, -0.31 and -1.46 kg·hm-2 for woodland, tea field and vegetable filed, respectively. The soil of vegetable field played a CH4 source role, while the tea field and woodland soils were sink of CH4 to the atmosphere as a whole. Seasonal variations of CH4 fluxes from tea field and vegetable field soils were observed, CH4 fluxes in spring and autumn seasons kept at relative high level, in other seasons, CH4 fluxes were low. A significant negative relationship between soil CH4 uptake rate and soil moisture was observed in woodland , and episodes of net CH4 release were observed in woodland, which may be caused by high soil moisture (WFPS higher than 70%). However, soil CH4 uptake rate and soil moisture were no correlation from tea filed and vegetable field. And no significant correlation between CH4 fluxes and soil temperature were found from all land use types. A negative correlation between soil CH4 emission and NH4+-N concentration was also observed from different land use type, while there was no significant relationship between soil CH4 emission and NO3--N concentration.

关 键 词：甲烷通量 菜地 茶园 红壤丘陵区 

分 类 号：X14[环境科学与工程—环境科学]