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1987年发生在大兴安岭北坡的特大火灾造成了森林资源的巨大损失,其森林景观恢复一直是人们关注的热点。本研究选取与森林生产力具有密切联系的郁闭度因子作为研究对象,以ArcView、ArcGIS等地理信息系统软件为研究平台,采用1987年和2000年两期森林资源二类调查数据,对郁闭度、火烧强度、抚育类型、地形因子等进行分级,通过数据叠加,探讨了森林郁闭度格局的恢复状况以及火烧强度、更新类型、地形因子对郁闭度恢复的影响。结果显示:2000年郁闭度等级构成与1987年火前相比发生了明显变化,无林地以及高郁闭度等级比重明显下降,较低郁闭度等级比重显著上升;火烧强度是影响火后恢复的初始因子,火烧强度与郁闭度等级呈负相关;更新措施短期内对郁闭度恢复影响不显著,但可以缩短森林演替的周期,对未来针叶林群落生产力恢复具有重要促进作用;地形因子中坡度对郁闭度恢复影响最为明显,其次为坡位,坡向影响最弱。图12表5参22。
The huge fire that took place on the northern slope of Daxinganling County in 1987 caused a huge loss of forest resources. The restoration of forest landscape has always been a hot spot for people’s attention. This study selected canopy closure factors closely related to forest productivity as the research object. Taking ArcView, ArcGIS and other geographic information system software as the research platform, using two types of forest resources in 1987 and 2000 survey data, , Fire intensity, tending type and topographical factors were graded. Through the data superposition, the restoration status of the forest canopy pattern as well as the influence of fire intensity, renewal type and topographical factors on canopy recovery were discussed. The results showed that the structure of canopy density in 2000 changed obviously compared with that before 1987, the proportion of non-forest land and high canopy density decreased significantly, and the proportion of lower canopy density increased significantly; The initial factor of restoration and fire intensity were negatively correlated with the degree of canopy density. The improvement measures had no significant effect on the restoration of canopy density in the short term, but could shorten the period of forest succession and play an important role in the restoration of productivity of coniferous forest community in the future The influence of slope degree on the restoration of canopy density was most obvious in topographic factors, followed by slope position and slope direction. Figure 12 Table 5 参 22.