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基于1989-1993、1994-1998、1999-2003三期全国森林资源清查资料,结合区域尺度的材积源生物量模型估算了三北防护林工程区3个时期天然林和人工林的生物量碳密度和碳贮量,分析了不同林种的碳贮量动态。结果表明:三北防护林工程区三个时期碳密度分别为35.21、36.01和41.56 t.hm-2,暗示我国的森林质量在逐步提高;碳贮量分别为458.10、519.96和1268.84 Tg(1 Tg=1012g),分别占全国森林碳贮量的9.89%、10.95%和24.23%。相对于人工林,天然林碳贮量仍是森林总碳贮量的主体,占71-84%,并且所占比例有增加趋势。随林龄的增加,天然林碳密度呈现显著增加趋势,但人工林仅在初始阶段呈现增加趋势,到近熟林就逐渐趋于稳定;人工林碳贮量随林龄增加而降低,但天然林以中龄林碳贮量最高,之后随林龄增加而降低。就林种而言,用材林和防护林占据主导地位,但随时间推移,防护林碳贮量所占比例越来越接近用材林。
Based on the three national forest inventory data of 1989-1993, 1994-1998 and 1999-2003, the biomass biomass carbon density of natural forests and plantations in Three North Shelter Forest Project areas Carbon storage, analyzed the carbon stock dynamics of different forest species. The results showed that the carbon density of the Three North Shelterbelt Project in the three periods were 35.21, 36.01 and 41.56 t.hm-2, respectively, suggesting that the forest quality in China was gradually increasing. The carbon stocks were 458.10, 519.96 and 1268.84 Tg respectively (1 Tg = 1012g) accounting for 9.89%, 10.95% and 24.23% of the national forest carbon stock respectively. Compared with plantations, natural forest carbon storage is still the main body of total forest carbon storage, accounting for 71-84%, and the proportion of the increase trend. With the increase of forest age, the density of natural forest showed a significant increase trend, but the plantation only showed an increasing trend in the initial stage, and nearly mature forest gradually became stable. The carbon storage of plantation decreased with increasing of age, The middle-aged forest carbon storage is the highest, then decreases with the increase of forest age. In the case of forest species, timber and shelter dominate but, over time, the proportion of shelterbelt carbon stocks has become closer to that of timber forests.