该文采用定量分析法, 研究了湖北神农架千家坪地区川金丝猴 (Rhinopithecus roxellana) 现生栖息地优势树种的生态位宽度、生态位重叠和生态位相似比例, 分析了优势树种生态位对神农架川金丝猴生存的影响。结果如下:1) 在64000m2的样方中, 木本植物255种, 隶属于44科105属, 其中乔木23科51属129种, 灌木22科49属113种, 木质藤本7科9属13种。优势科主要有蔷薇科、樟科、槭树科、忍冬科、壳斗科和四照花科等。2) 生态位宽度在栖息地森林群落乔木层中最高的为红桦 (Betula albo-sinensis) (5.261), 华山松 (Pinus armandii) (4.545) 、巴山冷杉 (Abiesfargesii) (4.289) 和糙皮桦 (Betula utilis) (3.256) 次之;灌木层中最高的为红晕杜鹃 (Rhododendron erubescens) (2.245), 多枝柳 (Salixpolyclona) (2.064) 、华中山楂 (Crataegus wilsonii) (1.508) 和陇东海棠 (Malus kansuensis) (1.453) 次之。3) 主要树种生态位宽度大于1的有30种, 占总数的11.67%, 其中21种是川金丝猴食源植物, 占神农架川金丝猴食源植物总数的10.40%;重要值排名前25位的树种中, 18种为食源植物, 占重要值总和的74.50%。4) 优势种的生态位重叠值在0.4以上的有7对种群;大部分种群的生态位相似性比值在0~0.3之间, 占全部种对的83.82%。结果表明, 神农架川金丝猴栖息地植物组成复杂, 优势种多为食源植物;优势种的生境高度相似、生态位多有重叠、种间竞争较为激烈, 将导致现有栖息地森林群落结构及植物组成发生变化, 食源植物短缺, 甚至栖息地面积缩减等现象, 这些都会影响川金丝猴的生存。因此, 加强保护神农架千家坪川金丝猴现生栖息地森林为川金丝猴创造适宜生存空间迫在眉睫。

Aims Study of niche characters of dominant species of the tree layer in Rhinopithecus roxellana forest habitat can assist in understanding how populations use biological resources, interact and adapt, as well as coevolve with tree-inhabiting primates.

Methods We quantitatively analyzed niche breadth, niche overlap, and niche similarity proportion of the dominant species of Rhinopithecus roxellana habitat in Qianjiaping, Shennongjia National Nature Reserve, Hubei Province and analyzed niche effects of dominant species on the survival of Rhinopithecus roxellana.

Important findings We recorded 255 woody plants from 44 families and 105 genera in a 64 000 m2 quadrat; there were 129 trees from 23 families and 51 genera, 113 shrubs from 22 families and 49 genera and 13 lianas from 9 genera and 7 families. Dominant families included Rosaceae, Lauraceae, Aceraceae, Caprifoliaceae, Fagaceae and Cornaceae. Maximum niche breadth in the arboreal layer occurred in Betula albo-sinensis (5.261), followed by Pinus armandii (4.545), Abies fargesii (4.289) and Betula utilis (3.256). Maximum in the shrub layer occurred in Rhododendron erubescens (2.245), followed by Salix polyclona (2.064), Crataegus wilsonii (1.508) and Malus kansuensis (1.453). Thirty species (11.67% of the plants) had a niche breadth >1; 21 of these species are forage plants, accounting for 10.40% of such plants. Eighteen of these plants account for 74.50% of the importance value of the top 25 species. Niche overlap occurred in dominant species, and seven pairs of these species had an overlap index >0.4. Nearly 83.82% of the species had a niche similarity proportion of 0-0.3. Results suggested that the plant composition of Rhinopithecus roxellana habitat in Shennongjia National Nature Reserve is diverse and the most dominant species are forage plants, but the dominant species are similar, with overlapping niches and strong competition. The survival of Rhinopithecus roxellana would be disadvantaged by changes in the current population structure and plant composition, shortage of grazing plants and decreased habitat. Therefore, it is crucial to protect the current habitat and to construct a more appropriate habitat for Rhinopithecus roxellana in Qianjiaping, Shennongjia National Nature Reserve.