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作为生态学中重要的理论之一,生态位研究有助于评估物种在特定资源环境下多维空间中综合利用资源的能力和竞争水平[1-3],目前已发展成为科学理解群落结构、分析种内和种间竞争关系及共存机制、评估种群在群落中地位等方面的重要手段[4-6]。根据生态位理论,同域分布且生态需求相近的物种,通过生态位分化可有效减少或避免有限资源条件下的竞争[7],且必须通过一定的生态位分化才可达到稳定共存[8]。科学对比同域分布近缘物种的生态位特征与分化程度,对于针对性保护与管理策略的制定具有重要的现实意义[9]。
横断山区是我国重要的生态安全屏障区,是全球36个生物多样性热点地区之一(https://www.conservation.org/priorities/biodiversity-hotspots)。贡嘎山是横断山区中断大雪山的主脉,该区域物种丰富且特有性高[10-12]。早期的研究已发现该地区分布有白马鸡(Crossoptilon crossoptilon)与多种雉类物种共存现象[13],且白马鸡和血雉(Ithaginis cruentus)的优势度较高(见表1)。白马鸡和血雉同为鸡形目(Galliformes)雉科(Phasianidae)物种,同属古北界,均为留鸟,同被IUCN濒危物种红色名录列为近危(Near Threatened, NT)等级,分布型均为喜马拉雅-横断山区型[14,15]。二者还具有相近的体型特征和食性需求[16],同域分布情况下很可能成为潜在竞争关系,因此可以作为研究大型雉类物种生态位分化的理想选择。白马鸡和血雉同为国家II级重点保护野生动物,且白马鸡为我国特有种[16],二者本身具有重要的保护意义和研究价值。国内关于白马鸡和血雉的研究报道较早,在生境选择和空间分布等方面已有部分研究[17-22]。然而,目前关于二者同域分布情况下的生态位分化研究仅限于生境选择和空间利用(均为生境维度)上[17,19,22],尚缺乏食物和时间维度[23]上的研究报道。
变量
Variables类别
Category有效相机位点
Effective camera
monitoring site血雉
Ithaginis cruentus白马鸡
Crossoptilon crossoptilon拍摄位点数
No. of sites with
monitoring records独立有效记录
No. of independent
records拍摄位点数
No. of sites with
monitoring records独立有效记录
No. of independent
records植被类型
Vegetation types针阔混交林
Mixed coniferous
broad-leaved forest88 24 159 28 157 针叶林 Coniferous forest 47 19 91 23 79 灌丛 Shrub forest 16 6 40 2 11 草甸 Grassy marshland 4 0 0 0 0 流石滩 Alpine screes 5 0 0 0 0 海拔段
Elevation (m)2672~3000 m 26 1 18 0 0 3001~3400 m 70 25 140 23 53 3401~3800 m 47 19 83 25 174 3801~4200 m 12 4 49 5 20 4201~4620 m 5 0 0 0 0 Table 1. Distribution of camera-trap sites and species monitoring conditions in different vegetation types and elevations
以往的研究主要基于传统调查方法(如样带法)开展,在针对目标物种全天候24 h分布和行为数据的获取上具有一定局限,而红外相机技术在这方面具有明显优势[24-25]。本研究在四川贡嘎山国家级自然保护区利用红外相机技术对白马鸡和血雉开展持续一年的监测研究,利用红外相机数据来比较分析二者在分布海拔与植被类型以及日活动节律方面的差异性,为进一步探究同域分布下近缘物种的共存机制和针对性保护管理策略的制定提供重要的研究数据。
Spatio-Temporal Niche Differentiation of White Eared Pheasant (Crossoptilon crossoptilon) and Blood Pheasant (Ithaginis cruentus) in Gongga Mountain National Nature Reserve, Sichuan Province
doi: 10.12172/202107310001
- Received Date: 2021-07-31
- Available Online: 2022-03-10
- Publish Date: 2022-04-26
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Key words:
- Crossoptilon crossoptilon /
- Ithaginis cruentus /
- Sympatric distribution /
- Niche differentiation /
- Daily activity rhythm
Abstract: It is of great practical significance to study niche differentiation of sympatric species for integrated conservation and management of species in different regions. From May 2017 to April 2018, infrared camera traps were installed to continuously monitor the sympatric distribution of White Eared Pheasant (Crossoptilon crossoptilon) and Blood Pheasant (Ithaginis cruentus) in Gongga Mountain National Nature Reserve, Sichuan province. Kruskal-Wallis H test and kernel density estimation were used to compare and analyze the differences in utilization of altitude, vegetation type and daily activity rhythm of the two species in dry and rainy seasons with the infrared camera data. The results were as follows: 1) The distribution camera positions of C. crossoptilon (53) and I. cruentus (49) were similar, with 24 identical sites, all of which were distributed only in the three vegetation types of coniferous and broad-leaved mixed forest, coniferous forest and shrub forest. 2) The altitude distribution range of I. cruentus (2981~3930 m) and C. crossoptilon (3067~3930 m) was similar, but the average altitude distribution of C. crossoptilon was significantly higher than that of I. cruentus (3600.44 m ± 227.97 m vs. 3412.67 m ± 313.32 m; Z= −7.022, P<0.01). 3) Both C. crossoptilon and I. cruentus had obvious preference for coniferous and broad-leaved mixed forest, followed by coniferous forest. The utilization rate of shrub forest was the lowest, but there were differences in the utilization of different vegetation types between the two species. 4) The daily activity rhythm of C. crossoptilon showed three activity peaks, which was obviously different from the one activity peak of I. cruentus (Δ=0.85, P=0.002). 5) Compared with different seasons, there was no significant difference in daily activity rhythm between C. crossoptilon and I. cruentusin rainy season (Δ=0.84, P=0.07), but there was significant difference in dry season (Δ=0.86, P=0.04). This study has accumulated important basic data for studying the niche differentiation of sympatric pheasant species and can provide important scientific data for further exploring the coexistence mechanism of sympatric species and the development of targeted conservation and management strategies.