The anthropogenic managements of forest have created a network of roads resulting in the loss and alternation of habitat. To better understand road′s impact on animal habitats, we assessed the habitat pattern of sables(Martes zibellina), one of rodents within national first-class protected species, when roads are considered in Huzhong area in Da Hinggan Mountains, northeastern China. Employing published literatures about behavior ecology, aerial photographs and forest stand maps, we classified the study area into three habitat types including best-suitable, suitable and unsuitable habitats based on sable habitat requirements at the landscape scale including four variables derived from forest source map with attribute database. Results indicated the loss and significant fragmentation of best-suitable habitat and home range habitat when roads, especially 150 m avoidance distance of roads, were considered. The roads reduced and fragmented highly suitable habitats more significantly during earlier development period than the later development period. Additionally, the suitable area percentage increased with increasing distance to roads. This study helped to identify the suitable area for sables and location of sable population. Also, this study suggested the passage construction and road management involving road closure and removal will reduce the fragmentation functionally and benefit the sable population.
LI YuehuiWU WenXIONG ZaipingHU YuanmanCHANG YuXIAO Duning
Forest management such as timber harvesting shapes fire regimes and landscape patterns, and these patterns often differ significantly from those under natural disturbances. Our objective was to examine the effects of timber harvesting modes on fire regimes and landscape patterns in a boreal forest of Northeast China. We used a spatially explicit landscape model, LANDIS, to simulate the changes of forest landscape in the Huzhong forest region of the Great Khingan Mountains under no-cutting, clear-cutting, gradual-cutting and selective-cutting modes. Results showed that:(1) the fine fuel loadings generally decreased while the coarse fuel loadings increased with the increase of timber harvesting intensity;(2) the potential burn area significantly varied among different cutting modes, but the potential fire frequency had no obvious difference. Moreover, timber harvesting generally increased the potential fire risk;(3) clear-cutting mode significantly decreased the mean patch size and the aggregation of larch forests and increased the mean patch size and the aggregation of white birch forests. Therefore, clear-cutting mode should be abandoned, and selective-cutting mode be recommended for the sustainable forest management in the Great Khingan Mountains.