酸雨对中国陆地生态系统土壤呼吸影响的整合分析  

Effects of acid rain on soil respiration in Chinese terrestrial ecosystems:A meta-analysis

作　　者：刘丰彩 杨燕华 江军 俞梦笑 夏诗婷 闫俊华[1] 王应平 LIU Fengcai;YANG Yanhua;JIANG Jun;YU Mengxiao;XIA Shiting;YAN Junhua;WANG Yingping(South China Botanical Garden,Chinese Academy of Sciences,Guangzhou 510650,China;Guangdong Eco-Engineering Polytechnic,Guangzhou 510520,China;University of Chinese Academy of Sciences,Beijing 100049,China;Commonwealth Scientific and Industrial Research Organization,Aspendale Victoria 3195,Australia)

机构地区：[1]中国科学院华南植物园,广州510650 [2]广东生态工程职业学院,广州510520 [3]中国科学院大学,北京100049 [4]澳大利亚联邦科工组织,维多利亚3195

出　　处：《生态学报》2022年第24期10191-10200,共10页Acta Ecologica Sinica

基　　金：国家自然科学基金项目(31901296);广东省基础与应用基础研究基金项目(2021A1515010652);广州市基础研究计划项目(202102020289)

摘　　要：通过整合分析(Meta-analysis)国内外公开发表的81篇模拟酸雨实验论文的2683条有效观测数据,量化了酸雨对中国3个主要陆地生态系统(森林、草地和农田)土壤呼吸(Rs)及其组分(自养呼吸(Ra)、异养呼吸(Rh))的影响。结果表明,酸雨显著降低了Rs(-9.6%)、Rh(-7.7%)和Ra(-11.7%);酸雨pH越低,Rs及其组分的降幅越大;野外实验对Rh和Ra的负效应大于温室实验。酸雨对Rs的负效应在农田最大(-14.7%),草地次之(-10.8%),森林最小(-8.0%);森林Rh、Ra对酸雨的响应与Rs一致,不同林型间差异不显著;草地Rh和Ra在酸雨处理下分别显著降低和增加。Rs、Rh与土壤pH显著正相关,与土壤有机碳(SOC)显著负相关;Rh和Ra分别与地上和地下生物量显著正相关。酸雨对Rs和Ra的负效应随纬度的增加而减弱,随年平均温的升高而增强,对Rs的正效应随年平均降水的降低而增强。研究表明,酸雨不仅降低了土壤pH,抑制了植物生长,减少了植物向土壤的碳输入,还降低了微生物活性,减少了Rh,导致SOC分解降低,因而未显著改变土壤碳库。研究结果将为全球变化背景下我国陆地生态系统的碳预算提供科学借鉴。Anthropogenic activities over the last four decades have increased depositions of sulfur dioxide(SO)and nitrogen oxides(NOx)by three to five fold in China,which resulted in a serious problem of acid rain with adverse effects on terrestrial carbon cycle.Soil respiration(Rs)as the second largest flux for the most terrestrial carbon cycle,and its two components(i.e.,autotrophic respiration(Ra)and heterotrophic respiration(Rh))are extremely sensitive to anthropogenic acid rain due to its detrimental effects on plant growth and soil microbes.Although numerous ecosystem-level manipulative experiments were conducted to explore the underlying mechanisms how acid rain affected Rs,a quantitative synthesis of previous studies on the effects of acid rain on Rs and its two components across different terrestrial ecosystems was scarce.By conducting a meta-analysis of 2683 observations from 81 independent experimental studies,we quantified the directions and magnitudes of the responses of Rs,Ra,and Rh to simulated acid rain(SAR)in three major terrestrial ecosystems(i.e.,forest,grassland,farmland)in China.Across all the experimental studies,our results showed that SAR significantly reduced Rs(-9.6%),Rh(-11.7%)and Ra(-11.7%),and the degree of reduction was proportional to the pH of SAR.The negative effects of SAR on Rh and Ra were greater in field experiment than that in pot experiment due to the differences in the intensity of SAR and experimental duration.Among different terrestrial ecosystem types,the negative effect of SAR on Rs was the most negative in farmland ecosystems(-14.7%),followed by grassland(-10.8%)and forest(-8.0%)ecosystems.The responses of Rh and Ra to SAR in forest ecosystems were consistent with that of Rs,and there were no significant differences among different forest types(i.e.,coniferous forest,coniferous and broadleaved mixed forest and broadleaved forest).In grassland ecosystems,the response to SAR was negative for Rh,but positive for Ra.Linear-regression analysis showed that Rs and Rh were positively co

关 键 词：有机碳 异养呼吸 生物量 土壤PH 

分 类 号：X144[环境科学与工程—环境科学] S154.1[农业科学—土壤学]