【摘要】 利用标准样方法研究了川西最主要的两种退耕还林植被(苦竹林和桦木林)在恢复初期生态系统碳储量、碳素密度以及空间分配特征。结果表明:(1)苦竹不同器官碳素密度为0.348 5~0.518 6 gC/g,桦木不同器官碳素密度为0.451 9~0.513 7 gC/g;(2)苦竹林林下枯落物的碳素密度为0.341 7 gC/g,桦木林林下枯落物的碳素密度为0.395 3 gC/g;(3)不同植物器官的碳储量分配与各器官的生物量显著相关。苦竹林分中竹秆生物量占48.87%,其碳储量占53.06%;桦木林树干生物量占57.25%,其碳储量占57.27%;(4)两种森林生态系统碳储量的空间分布格局表现为以土壤碳储量最大,占64.19%~82.59%,其次是乔木层,占21.93%~33.90%,最小是枯落物层,占0.27%~1.91%;(5)在退耕还林初期,植被恢复后土壤各层碳素密度小于对照的各层土壤碳素密度,土壤有机碳储量减少;(6)退耕地转变为森林后,成为大气CO2的一个重要碳汇。更多还原

【Abstract】 The storages,densities and spatial patterns of carbon in bamboo(Pleioblastus amarus) and birch(Betula platyphylla) forest ecosystems which had been converted by farmland 5 years ago were studied to understand the contribution of forests converted by farmland(FVF) to carbon sink.The results indicated that:(1)the carbon density of different bamboo organs varied from 0.348 5 gC/g to 0.518 6 gC/g,and the carbon density of different birch organs varied from 0.4519 gC/g to 0.513 7 gC/g;(2)the carbon density in litter layer were 0.341 7 gC/g and 0.395 3 gC/g beneath bamboo and birch forests,respectively;(3)the carbon storage was significantly and positively correlated with the biomass of the corresponding organs,the biomass carbon storage accounting for 48.87% and 53.06% of the total biomass and carbon storage in the bamboo forest,and for 57.25% and 57.27% in the birch forest,respectively;(4)in the forest,the soil held the largest carbon storage,the second was plant organs,and the smallest was the litter layer;(5)the soil carbon storage decreased because of the artificial disturbance during the initial of FVF;(6)the land of FVF would develop an important carbon sink.更多还原