Carbon accumulation and distribution were studied in three plots of a 13 years old Chinese fir (Cunninghamia lanceolata) forest in Daqingshan,Guangxi. The results showed that the average carbon concentration in all ...Carbon accumulation and distribution were studied in three plots of a 13 years old Chinese fir (Cunninghamia lanceolata) forest in Daqingshan,Guangxi. The results showed that the average carbon concentration in all organs was in the following order: leaf (510.5)>bark (501.8)>wood (485.1)>root (476.5)>branch(462.1) (g·kg -1 ). The carbon concentration of soil (to 60 cm depth) ranged from 11.4 to 21.1 (g·kg -1 ),with an average of 16.6 (g·kg -1 ). Carbon concentration of surface soil (to 20 cm) was higher than the other layer. The average carbon concentrations (g·kg -1 ) in different layers were in the order as: trees (497)> shrub (437.5) >standing litters (437.5)>herb (407.8). The carbon storage of the forest ecosystem was in order of soil layer>vegetation >standing litter. Of total average carbon,23.87% was in vegetation component,74.27% in soil (60 cm depth),and only 1.86% in standing ground litter layer. The tree layer occupied 22.93% of total carbon storage in the ecosystem and 96.07% of carbon storage in the vegetation layer. The carbon storage in different organs was positively related to the biomass of corresponding organs. Trunk accumulated the highest carbon storage,comprising 58.40% of carbon storage in tree layer. Secondly,root made up 20.09% of total tree carbon. The annual net productivity of Chinese fir plantation was 10.10 t·hm -2 a -1 ,stored carbon up to 4.67 t·hm -2 a -1 ,equal to 17.13 t·hm -2 a -1 of CO2. Chinese fir plantation was an important sink of atmospheric CO2. But its capacity of C sequestration decreased gradually in this region.展开更多
采用BIOME-BGC模型对广东鹤山的马占相思(Acacia mangium)人工林生态系统1985-2100年间的碳格局及其动态变化进行了模拟。结果表明,马占相思生物量在前12a增长较快,之后增长缓慢,最终达到300t hm^-2;预计2100年马占相思生物量在...采用BIOME-BGC模型对广东鹤山的马占相思(Acacia mangium)人工林生态系统1985-2100年间的碳格局及其动态变化进行了模拟。结果表明,马占相思生物量在前12a增长较快,之后增长缓慢,最终达到300t hm^-2;预计2100年马占相思生物量在于、根、叶中的分配分别为73.91%、21.74%和4.35%。马占相思人工林的碳贮量在前12a增长较快,之后增长缓慢并最终维持在325t C hm^-2左右,在造林初始阶段主要分布于土壤中,之后在植被、土壤和凋落物3大碳库中的分配分别为43.08%、52.30%和4.62%;马占相思净初级生产力(NPP)在4-12a较大,最大可达11t C hm^-2,之后下降至3-6t C hm^-2;马占相思叶面积指数(LAX)前3a增长迅速,5a达到7.84,之后下降,约为2.7-5.0;LAJ与NPP的回归分析结果显示LAI可能是限制马占相思林NPP增长的主要因子。模拟结果还显示马占相思林前期生长迅速,但随后生长缓慢,叶生物量还出现负增长现象。因此,我国南亚热带地区在以马占相思作为先锋树种进行地带性森林植被恢复时,可在12a后进行林分改造。展开更多
文摘Carbon accumulation and distribution were studied in three plots of a 13 years old Chinese fir (Cunninghamia lanceolata) forest in Daqingshan,Guangxi. The results showed that the average carbon concentration in all organs was in the following order: leaf (510.5)>bark (501.8)>wood (485.1)>root (476.5)>branch(462.1) (g·kg -1 ). The carbon concentration of soil (to 60 cm depth) ranged from 11.4 to 21.1 (g·kg -1 ),with an average of 16.6 (g·kg -1 ). Carbon concentration of surface soil (to 20 cm) was higher than the other layer. The average carbon concentrations (g·kg -1 ) in different layers were in the order as: trees (497)> shrub (437.5) >standing litters (437.5)>herb (407.8). The carbon storage of the forest ecosystem was in order of soil layer>vegetation >standing litter. Of total average carbon,23.87% was in vegetation component,74.27% in soil (60 cm depth),and only 1.86% in standing ground litter layer. The tree layer occupied 22.93% of total carbon storage in the ecosystem and 96.07% of carbon storage in the vegetation layer. The carbon storage in different organs was positively related to the biomass of corresponding organs. Trunk accumulated the highest carbon storage,comprising 58.40% of carbon storage in tree layer. Secondly,root made up 20.09% of total tree carbon. The annual net productivity of Chinese fir plantation was 10.10 t·hm -2 a -1 ,stored carbon up to 4.67 t·hm -2 a -1 ,equal to 17.13 t·hm -2 a -1 of CO2. Chinese fir plantation was an important sink of atmospheric CO2. But its capacity of C sequestration decreased gradually in this region.
文摘采用BIOME-BGC模型对广东鹤山的马占相思(Acacia mangium)人工林生态系统1985-2100年间的碳格局及其动态变化进行了模拟。结果表明,马占相思生物量在前12a增长较快,之后增长缓慢,最终达到300t hm^-2;预计2100年马占相思生物量在于、根、叶中的分配分别为73.91%、21.74%和4.35%。马占相思人工林的碳贮量在前12a增长较快,之后增长缓慢并最终维持在325t C hm^-2左右,在造林初始阶段主要分布于土壤中,之后在植被、土壤和凋落物3大碳库中的分配分别为43.08%、52.30%和4.62%;马占相思净初级生产力(NPP)在4-12a较大,最大可达11t C hm^-2,之后下降至3-6t C hm^-2;马占相思叶面积指数(LAX)前3a增长迅速,5a达到7.84,之后下降,约为2.7-5.0;LAJ与NPP的回归分析结果显示LAI可能是限制马占相思林NPP增长的主要因子。模拟结果还显示马占相思林前期生长迅速,但随后生长缓慢,叶生物量还出现负增长现象。因此,我国南亚热带地区在以马占相思作为先锋树种进行地带性森林植被恢复时,可在12a后进行林分改造。