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1987年发生在大兴安岭北坡的特大森林火灾,总过火面积达1.33×106hm2,形成了各种火烧强度区与未火烧区构成的异质镶嵌体。火烧强度、地形以及火后人类的恢复干预都不同程度地对火后森林恢复产生了影响。研究目的有二:一是为了揭示火后森林恢复状况;二是探寻火烧强度、地形以及火后更新措施等因素对火后森林恢复的影响程度。选取了位于火烧区的图强林业局中部的育英和图强两林场为研究区,选取反映森林景观质量的郁闭度指标作为研究对象,利用地理信息系统软件,将1987年火前与2000年的郁闭度等级分布图叠加,分析火后森林质量的恢复状况;利用多元线性回归法对火烧强度、海拔、坡度、坡向、坡位等地形因子以及各种更新方式对郁闭度恢复的影响程度进行了定量研究。结果显示,2000年郁闭度等级与火前相比发生了明显变化,2000年各林型郁闭度优势等级均由较高的等级4,5降为等级3;而等级1的比重也有所降低。表明,火后森林总体生长状况良好,无林地比重降低,但由于恢复时间较短,具有较高郁闭度的森林所占比重仍较低。多元线性回归显示,各因子均对火后郁闭度恢复产生了显著性影响。其中,海拔影响最大,与郁闭度等级呈正相关;其次是火烧强度,呈负相关;其它地形因子以及更新方式影响较小。
In 1987, a large forest fire occurred on the northern slope of Daxinganling with a total over-fire area of 1.33 × 106hm2, forming heterogeneous mosaics with various fire intensity and un-burning zones. Fire intensity, topography and post-fire human recovery intervention all affected, to varying degrees, the post-fire forest restoration. The purpose of the study is twofold: first, to reveal the state of forest restoration after fire; second, to explore the extent of the influence of fire intensity, topography and post-fire renewal measures on forest restoration after fire. In the middle part of Tuqiang Forestry Bureau located in the fire area, Yuying and Tuqiang two forest farms were chosen as the research area, the canopy density index reflecting the forest landscape quality was selected as the research object, and the geographic information system software was used to compare the pre-fire and post- The degree of canopy density distribution was superposed to analyze the recovery status of forest quality after fire; the topographic factors such as fire intensity, altitude, slope, aspect, slope position and other update methods were used to recover canopy density by using multivariate linear regression method The degree of influence was quantified. The results showed that the degree of canopy closure in 2000 changed significantly compared with that before the fire. In 2000, the superiority grades of canopy density varied from higher grades 4 and 5 to grade 3, reduce. The results showed that the overall forest fire was in good condition and the proportion of non-forest land decreased. However, due to the short recovery time, the proportion of forests with high canopy density remained relatively low. Multivariate linear regression showed that each factor had a significant effect on the recovery of canopy after fire. Among them, the altitude had the greatest impact, which was positively correlated with the degree of canopy closure; followed by the intensity of fire, which was negatively correlated; and other topographic factors and the updating methods had less influence.