-
种群数量的下降通常会对生态系统的功能和服务产生直接影响[1,2],因此,对种群进行保护是十分重要的。保护行动与保护措施的落地,往往是通过对局域种群及其栖息地进行保护来实现的,所以种群也是保护管理的核心。虽然种群和生境是动态变化的,但是必须根据一定的地理范围,来对保护管理单元进行划分,以确定监测与保护的实体[3]。
遗传学方法经常被用来确定种内单元(intraspecific units),如进化显著单元(evolutionarily significant units, ESUs)和管理单元(management units, MUs)。虽然ESUs和MUs在概念和标准上都得到了理论的认可,但其是否能为切实的保护提供依据,还有待检验[4]。它们虽然可以在概念上识别出不同的种内单元,但是无法给出种内单元的地理空间边界。而从实用意义上看,保护行动总是在特定的地理范围内展开的,所以划定种内单元的空间边界,对于保护管理具有重要意义。
R的habCluster包提供了划分种内单元空间边界的工具[5]。habCluster引入了图论中社区探测(community detection)的思路,通过(1)评估景观中栖息地栅格两两之间的连通性,(2)将具有强连通性的栅格聚集到同一个集群(cluster)中,来划定景观层面上种内单元的边界。
大熊猫(Ailuropoda melanoleuca)是我国特有的珍稀濒危动物,现仅分布于秦岭、岷山、邛崃山、凉山、大相岭和小相岭六个山系内[6]。其中,大相岭山系是现存大熊猫数量、栖息地面积均较少的山系。许多学者在大相岭山系开展了多种有关大熊猫的研究,从遗传多样性[7]、种群生存力分析[8]、栖息地分布及评价[9,10]、生境廊道规划[11]等方面,为有效保护大熊猫及其栖息地提供科学依据。然而,尚无在景观层面,对大相岭山系的大熊猫种群进行种内单元划分的研究。利用大相岭山系的大熊猫栖息地适宜性指数(habitat suitability index, HSI)图层,使用habCluster包,对种内单元空间边界进行了划分,并与现有保护区进行比较,以期为大相岭山系的大熊猫保护提供依据,为其他区域的野生动物保护管理提供借鉴。
habCluster-based Intraspecific Units Identification of Giant Pandas (Ailuropoda melanoleuca) in Daxiangling Mountains
More Information-
摘要: 划分物种种内单元的地理空间边界,对于实现有效的保护管理具有重要意义。本文以大相岭山系及其周边地区的大熊猫(Ailuropoda melanoleuca)栖息地适宜性指数(habitat suitability index, HSI)图层为基础,使用habCluster包,对大相岭山系大熊猫的种内单元进行了划分。研究结果表明,大相岭山系共被划分为20个大熊猫种内单元。这些种内单元的划分结果,良好地体现了研究区域被低HSI值的栅格所分隔的情况,可作为对大熊猫生境斑块的指示。大熊猫种内单元与现有保护区的叠加分析表明,大相岭自然保护区被划分至3个大熊猫种内单元,瓦屋山自然保护区被划分至4个大熊猫种内单元,羊子岭自然保护区被划分至2个大熊猫种内单元。对跨大相岭-瓦屋山种内单元,需要不同区域与级别的行政主管部门通力配合协调一致,以加强对该区域野生大熊猫的保护管理。对大相岭泥巴山种内单元,需降低道路对该区域大熊猫栖息地的负面影响,从而避免其栖息地进一步破碎化。研究为大相岭山系大熊猫的保护管理提供了新的视角,并可作为对其他区域的野生动物进行保护管理的借鉴。Abstract: Delineating the geographical boundaries of intraspecific units is important for effective conservation management. Using the habitat suitability index (HSI) map of giant panda (Ailuropoda melanoleuca) in the Daxiangling Mountains and its surrounding areas, we delineated the intraspecific units for pandas in this region with R package “habCluster”. The results showed that the Daxiangling Mountains was divided into 20 giant panda intraspecific units. These boundary delineations from our results show good performance in detecting areas that are separated by raster cells with low HSI values, thus could serve as good indicator of giant panda habitat patches. The overlap analysis with nature reserves suggested that the Daxiangling Nature Reserve was divided into 3 intraspecific units, the Wawushan Nature Reserve into 4 units, and the Yangziling Nature Reserve into 2 units. For the trans-Daxiangling-Wawushan intraspecific unit, coordinated conservation efforts is needed among the departments of different administrative regions in order to strengthen the protection and management of its wild population. While for the Niba Mountain intraspecific unit, it is indispensable to reduce the negative impacts of the highway that across it, so as to avoid its habitat from further fragmentation. Our study provided a new perspective for the conservation implementation of the giant pandas in the Daxiangling Mountains, and can be applied to wildlife conservation in other regions.
-
-
[1] Ceballos G, Ehrlich P R, Dirzo R. Biological annihilation via the ongoing sixth mass extinction signaled by vertebrate population losses and declines[J]. PNAS, 2017, 114(30): E6089−E6096. [2] Brodie J F, Williams S, Garner B. The decline of mammal functional and evolutionary diversity worldwide[J]. PNAS, 2021, 118(3): 1−6. [3] Palsbøll P J, Bérubé M, Allendorf F W. Identification of management units using population genetic data[J]. Trends in Ecology and Evolution, 2007, 22(1): 11−16. doi: 10.1016/j.tree.2006.09.003 [4] Moritz C. Defining “Evolutionarily Significant Units” for conservation[J]. Trends in Ecology and Evolution, 1994, 9(10): 373−375. doi: 10.1016/0169-5347(94)90057-4 [5] Zhang C, Li J, Yang B, Dai Q. habCluster: Identifying Geographical Boundary among Intraspecific Units Using Community Detection Algorithm in R[J]. Frontiers in Conservation Science, 2022, August: 1−9. [6] 国家林业和草原局. 全国第四次大熊猫调查报告[M]. 北京: 科学出版社, 2021: 21−23. [7] 方盛国,冯文和,张安居,等. 大相岭山系大熊猫数量及遗传多样性的DNA指纹检测[J]. 四川大学学报(自然科学版),1999,36(3):627−630. [8] 张泽均,胡锦矗. 从种群生存力分析看大相岭大熊猫未来[J]. 四川师范学院学报(自然科学版),2003,24(2):141−144. [9] 冉江洪,曾宗永,刘世昌,等. 四川大相岭大熊猫种群及栖息地调查[J]. 四川大学学报(自然科学版),2006,43(4):889−893. [10] 徐卫华,欧阳志云,蒋泽银,等. 大相岭山系大熊猫生境评价与保护对策研究[J]. 生物多样性,2006,14(3):223−231. doi: 10.3321/j.issn:1005-0094.2006.03.005 [11] 侯宁,戴强,冉江洪,等. 大相岭山系泥巴山大熊猫生境廊道设计[J]. 应用与环境生物学报,2014,20(6):1039−1045. [12] Qing J, Yang Z S, He K, et al. The minimum area requirements (MAR) for giant panda: An empirical study[J]. Scientific Reports, 2016, 6: 37715. doi: 10.1038/srep37715 [13] Rudnick D A, Ryan S J, Beier P, et al. The Role of Landscape Connectivity in Planning and Implementing Conservation and Restoration Priorities[R]. Ecological Society of America, 2012, Report No. 16: 1−20.