沐川县退耕还林生态恢复地碳截留效应的研究

对四川省沐川县几种不同植被覆盖类型下生态系统的植被碳储量、凋落物的碳储量和土壤有机碳的储量进行了研究.结果表明,不同土地植被覆盖类型下的植被碳储量、凋落物的碳储量和土壤有机碳的储量存在着一定的差异,其中以人工水杉Metasequoia glyptostroboides植被的碳储量最大.植被碳储量由高到低依次是人工水杉林、天然次生林、慈竹Neosinocalamus affinic林、农耕地、茶Camellia sinensis园;天然次生林凋落物的碳储量比其他的几种类型要高,分解后更利于土壤有机碳储量的增加;天然次生林土壤有机碳的储量均显著高于其他植被类型的碳储量,土壤有机碳储量由高到低的依次为次生林、慈竹林、水杉林、茶园和农耕地.人工水杉林和慈竹林土壤也能有效地截留大气中的CO2,而农业用地最不利于土壤有机碳的积累.5种植被类型下,总的碳储量由高到低的顺序为次生林、慈竹林、水杉林、茶园和农耕地.加强热带、亚热带和温带森林的保护,同时不断扩大人工林的种植面积,增加森林生态系统的有机碳的截留是缓解大气CO2浓度增加的一种重要措施.表5参16

Carbon sequestration of 5 ecological reestablishment vegetation types in Muchuan County of Sichuan

The study of the carbon reserves in vegetation and litter, and the reserve of soil organic carbon in the ecological system covered with several different vegetation types in Muchuan County, Sichuan Province, showed that there were some differences of carbon reserves among different vegetation types. The reserve of carbon in vegetation of Metasequoia glyptostroboides forest was the highest among them. The rank of carbon reserves in them was as follows: Metasequoia glyptostroboides forest >natural secondary forest>Neosinocalamus affinity forest>arable land>tea land. The carbon reserve in the litter of natural secondary forest was higher than other vegetation types. The decomposed litter could facilitate the increase in the organic carbon reserve in soil. The reserve of organic carbon in the soil of natural secondary forest was apparently higher than other vegetation types. The rank of organic carbon in the soil was as follows: natural secondary forest>Neosinocalamus affinity forest>Metasequoia glyptostroboides forest>tea land and arable land. The rank of total carbon reserves among different ecosystem types was as follows: natural secondary forest >Neosinocalamus affinity forest >Metasequoia glyptostroboides forest > tea land and arable land. Strengthening the protection of tropical, sub-tropical and temperate forests, enlarging the planting area of plantation and increasing the sequestration of organic carbon in the forest ecological system are important measures to slow down the increase in the concentration of CO_2 in the atmosphere.