不同营林面积情景下鹿科动物的潜在生境分布

在有人为干扰的森林景观中开展鹿科动物适宜生境分布研究,对于解决大尺度生境保护与小面积森林经营的矛盾问题有着重要的参考意义,也符合我国林区的现实需求.2013—2015年冬季进行的多次野外调查收集196处鹿科动物出现点信息,将这些点作为分布点数据,选取地形、景观类型、植被特征和人类干扰4类17种因子作为环境变量,利用最大熵模型方法,分析4种林下经营面积情景下小兴安岭铁力林业局马鹿和狍的潜在适宜生境分布特征及其对环境因子的响应.结果表明:模型预测精度达到优秀水平,稳定性好,鹿科动物的适宜生境主要集中在东部区域;不同情景下,两种鹿科动物的主要环境影响因子相似,均为距农田距离、距居民点距离、距河流距离、距营林区距离和海拔因子,其中,距营林区距离因子的贡献率稳定在4%～6%;两种鹿科动物躲避人类经营活动干扰的距离(1200～1300 m)较为接近.在无林下经营情景中,鹿科动物的适宜生境分布较广、面积较大;随着经营面积的增大,适宜生境面积减少;当经营面积扩大到现实情况的2～3倍时,鹿科动物栖息地面积缩减较为严重.

Potential habitat distribution for Cervids based on different forest management area scena-rios

It is theoretically and practically important to explore suitable habitat distribution of the Cervids for relieving the confliction between small-scale human management and large-scale habitat conservation in a human-disturbed forest landscape. Using the present locations of Cervids (n=196) observed in field investigations in 2013, 2014 and 2015, we grouped 17 environmental predictor variables into four predictor classes (terrain, habitat type, vegetation feature, and interference) and used those variables to build a maximum entropy (MaxEnt) model. Then, we estimated the potential habitat of red deer and roe deer, and determined the contribution of environmental factors to the distribution characteristics in four forest management area scenarios by this model. Results showed that models validation had high average accuracy and the stability appeared satisfactory. The potential suitable habitat for Cervids was located mostly in the eastern region. The environmental factors significantly affecting habitat suitability of red deer and roe deer were similar in different scenarios, and they were distance to farmland, distance to settlement, distance to river, distance to management area and elevation. Distance to management area factor was found to have a certain extent effect on habitat suitability with contribution probability from 4% to 6%. The distance to management area was about 1200-1300 m both for red deer and roe deer. In none management scenario, the suitable habitat was widely distributed in large area. With the increase of management area, the suitable habitat decreased. When the management area expanded to the twofold or threefold of the current one, Cervids habitat shrank greatly.