长白山自然保护区历史森林景观的初步重建

本文在对环境因子(包括年均温、年降水量、海拔高度、坡度和坡向)进行空间表达的基础上,建立了长白山自然保护区当前森林景观垂直带(包括阔叶红松林、云冷杉林、岳桦林和苔原)与这些环境因子间的逻辑斯蒂回归模型,然后利用1997年各环境因子的空间数字面来反推1975年森林景观带的空间分布,并根据1975年MSS遥感影像计算机监督分类的结果,用Kappa指数对模型预测结果进行验证。结果表明,苔原、岳桦林、云冷杉林和阔叶红松林1975年的预测分布面积分别为7243.83hm2、6517.08hm2、125570.16hm2和34264.80hm2,与遥感分类结果相比,苔原和云冷杉林的面积分别减少了29.04%和3.05%;岳桦林和阔叶红松林的面积分别增加了246.45%和8.6%。用逻辑斯蒂回归模型可以较好地预测苔原在保护区内的分布范围,同时在一定程度上也能预测阔叶红松林的分布范围,但是对岳桦林和云冷杉林分布范围的预测结果较差。尽管如此,作为一种方法性的探讨,本文可以为森林景观空间分布和环境因子变化的关系以及森林景观对气候变化的反应研究提供一种新思路。     

中国东北地区人为活动对森林景观格局及鹿科动物生境的影响（英文）

Species abundance and habitat distribution are two important aspects of species conservation studies and both are affected by similar environmental factors. Forest resource inventory data in 2010 were used to evaluate the patterns of habitat for target species of Cervidae in six typical forestry bureaus of the Yichun forest area in the Lesser Xing’an Mountains, northeastern China. A habitat suitability index(HSI) model was used based on elevation, slope, aspect, vegetation and age of tree. These five environmental factors were selected by boosted regression tree(BRT) analysis from 14 environmental variables collected during field surveys. Changes in habitat caused by anthropogenic activities mainly involving settlement and road factors were also considered. The results identified 1780.49 km2 of most-suitable and 1770.70 km2 of unsuitable habitat areas under natural conditions, covering 16.38% and 16.29% of the entire study area, respectively. The area of most-suitable habitat had been reduced by 4.86% when human interference was taken into account, whereas the unsuitable habitat area had increased by 11.3%, indicating that anthropogenic disturbance turned some potential habitats into unsuitable ones. Landscape metrics indicated that average patch area declined while patch density and edge density increased. This suggests that as habitat becomes fragmented and its quality becomes degraded by human activities, cervid populations will be threatened with extirpation. The study helped identify the spatial extent of habitat influenced by anthropogenic interference for the local cervid population. As cervid species clearly avoid human activities, more attention should be paid on considering the way and intensity of human activities for habitat management as fully as possible.