亚热带红壤丘陵区湿地松人工林固碳释氧效益研究

用标准样方法对19年生湿地松（〖WTBX〗Pinus elliottii〖WTBZ〗）人工林碳素含量及碳贮量进行了测定。结果表明，湿地松各器官的碳素含量在5092±046%～5438±026%之间波动，按碳含量高低排列为树叶>树枝>树干>树根>树皮，且各器官的碳素含量随年龄的增长而提高。不同林冠层枝、叶碳素含量存在差异，上层叶与下层叶的碳素含量较低，下层枝条碳素含量明显比上、中层枝条高。灌木层、草本层、凋落物层的碳素含量依次为4516±04%、4228±041%、4088±031%，土壤层碳素含量平均为043±004%，且随土壤深度的增加而明显递减。湿地松林生态系统碳贮量为12194 t〖DK〗·hm-2，其中乔木层碳贮量为8618 t〖DK〗·hm-2，占总量的7067%，下木层和凋落物层碳贮量分别为06 t〖DK〗·hm-2(049%) 和886 t〖DK〗·hm-2（727%）。林地土壤（0～60 cm）为263 t〖DK〗·hm-2，占总碳贮量的2157%。乔木层年净固碳量为454 t〖DK〗·hm-2，年净释氧量为1212 t〖DK〗·hm-2。采用造林成本法计算得出试区湿地松林平均每年发挥的净固碳释氧效益达9 034元〖DK〗·hm-2。

BENEFITS OF CO2 FIXATION AND O2 PRODUCTION OF ARTIFICIAL PINUS ELLIOTTII FOREST IN THE RED SOIL AND HILLY REGION OF SUBTROPICAL CHINA

The carbon content and storage were studied in 19 year old Pinus elliottii plantation by sampling plots.The results showed that carbon content in different organs of P.elliottii ranged between (5092±046)% and (5438±026)%，and decreased in the order of leaf>branch>wood>root >bark.The carbon content in branch and leaf increased with the aging of organs.The leaf carbon content of mid layer was slightly higher than that of the mid and up layers.And the branch carbon content of the down layer was much higher than that of the other two layers.The carbon content in shrub，herb and litter floor were（4516±04）%，(4228±041)%，and (4088±031)%，respectively.The average carbon content in the soil was (043±004)% and declined with the increase of soil depthThe total carbon storage in P.elliottii plantation ecosystem amounted to 12194 t〖DK〗·hm-2，of which the over storey stored 8618 t〖DK〗·hm-2 accounting for 7067% of the total storage.The carbon storage in under storey，litter floor and soil within the depth from 0 to 60 cm were 06 t〖DK〗·hm-2，886 t〖DK〗·hm-2 and 263 t〖DK〗·hm-2，accounting for 049%，727% and 2157%，respectively.The annual net carbon storage of P.elliottii forest was 454 t〖DK〗·hm-2 and the annual net O2 production was 1212 t〖DK〗·hm-2.The annual net benefits from CO2 fixation and O2 production of P.elliottii plantation was estimated to be 9 034 yuan〖DK〗·hm-2 by reforestation cost method.The data would provide scientific guideline for the protection of ecosystem and reasonable utilization of present resource.