Stabilization versus decomposition in alpine ecosystems of the Northwestern Caucasus:The results of a tea bag burial experiment  

作　　者：Tatiana G.ELUMEEVA Vladimir G.ONIPCHENKO Asem A.AKHMETZHANOVA Mikhail I.MAKAROV Joost A.KEUSKAMP 

机构地区：[1]Department of Geobotany,Biological Faculty,Lomonosov Moscow State University,119234 Leninskie Gory 1/12,Moscow,Russia [2]Department of General Soil Science,Faculty of Soil Science,Lomonosov Moscow State University,119234 Leninskqe Gory 1/12,Moscow,Russia [3]Ecology 8:Biodiversity Group,Utrecht University,P.O.Box 80.056,3508 TB Utrecht,The Netherlands [4]Netherlands Institute of Ecology(NIOO-KNA W),P.O.Box 59,6700 AB Wageningen,The Netherlands

出　　处：《Journal of Mountain Science》2018年第8期1633-1641,共9页山地科学学报（英文）

基　　金：supported by Russian Science Foundation(RSF),grant№16-14-10208

摘　　要：Mountainous areas exhibit highly variable decomposition rates as a result of strong local differences in climate and vegetation type. This paper describes the effect of these factors on two major determinants of the local carbon cycle: litter decomposition and carbon stabilization. In order to adequately reflect local heterogeneity, we have sampled 12 typical plant communities of the Russian Caucasus. In order to minimize confounding effects and encourage comparative studies, we have adapted the widely used tea bag index(TBI) that is typically used in areas with low decomposition. By incubating standardized tea litter for a year, we investigated whether(1) initial litter decomposition rate(k) is negatively correlated with litter stabilization(S) and(2) whether k or S exhibit correlations with altitude and other environmental conditions. Our results show that S and k are not correlated. Altitude, p H, and water content significantly influenced the stabilization factor S, while soil-freezing had no influence. In contrast, none of these factors predicted the decomposition rate k. Based on our data, we argue that collection of decomposition rates alone, as is now common practice, is not sufficient to understand carbon input to soils and can potentially lead to misleading results. Our data on community-specific decomposition and stabilization rates further constrain estimates of litter accumulation in subalpine communities and the potential effects of climate change.Mountainous areas exhibit highly variable decomposition rates as a result of strong local differences in climate and vegetation type. This paper describes the effect of these factors on two major determinants of the local carbon cycle： litter decomposition and carbon stabilization. In order to adequately reflect local heterogeneity, we have sampled 12 typical plant communities of the Russian Caucasus. In order to minimize confounding effects and encourage comparative studies, we have adapted the widely used tea bag index（TBI） that is typically used in areas with low decomposition. By incubating standardized tea litter for a year, we investigated whether（1） initial litter decomposition rate（k） is negatively correlated with litter stabilization（S） and（2） whether k or S exhibit correlations with altitude and other environmental conditions. Our results show that S and k are not correlated. Altitude, p H, and water content significantly influenced the stabilization factor S, while soil-freezing had no influence. In contrast, none of these factors predicted the decomposition rate k. Based on our data, we argue that collection of decomposition rates alone, as is now common practice, is not sufficient to understand carbon input to soils and can potentially lead to misleading results. Our data on community-specific decomposition and stabilization rates further constrain estimates of litter accumulation in subalpine communities and the potential effects of climate change.

关 键 词：Litter decomposition Alpine communities Tea bag index Carbon cycle 

分 类 号：S0[农业科学]