李雪萌1,2, 蒋际宝1,2, 张曾鲁1,2, 刘晓静3, 王亚利4, 吴宜钊1,2, 李银生1,2, 邱江平1,2, 赵琦1,2*
1 上海交通大学农业与生物学院, 上海 200240
2 上海长三角区域生态环境变化与综合治理国家野外科学观测研究站, 上海 200240
3 河南内乡宝天曼国家级自然保护区管理局, 河南内乡 474350
4 河南工业大学环境工程学院, 郑州 450001
Xuemeng Li1,2, Jibao Jiang1,2, Zenglu Zhang1,2, Xiaojing Liu3, Yali Wang4, Yizhao Wu1,2, Yinsheng Li1,2, Jiangping Qiu1,2, Qi Zhao1,2*
1 School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240
2 Shanghai Yangtze River Delta Eco-Environmental Change and Management Observation and Research Station, Ministry of Science and Technology, Ministry of Education, Shanghai 200240
3 Henan Neixiang Baotianman National Nature Reserve Administration, Neixiang, Henan 474350
4 School of Environmental Engineering, Henan University of Technology, Zhengzhou 450001
摘要：
Aim: Baotianman National Nature Reserve is located in the southern Funiu Mountain range in the eastern part of the Qinling Mountains, which belongs to the forest ecosystem, making it a focal point of biodiversity research. However, the current understanding of earthworm diversity is limited in the literature. Thus, the objectives of the present study are to investigate the earthworm diversity and their geographical distribution in Baotianman National Nature Reserve systematically, and to discuss the potential factors impacting the formation of earthworm diversity at a local scale.
Method: Earthworms specimens were collected from nine sampling sites at different altitudes in Baotianman National Nature Reserve during the rainy season using the ‘digging-hand-sorting’ method. Subsequently, five mitochondrial genes (COI, COII, ND1, 12S rRNA and 16s rRNA) were extracted and sequenced from the earthworms. The phylogenetic tree was constructed using the Bayesian method based on the sequenced mitochondrial genes. The phylogenetic diversity (SES-PD), phylogenetic structure (NTI & NRI) and α-diversity index were calculated using R-Studio. Additionally, structural equation modeling (SEM) was used to assess the potential environmental factors influencing the formation of earthworm diversity. The combination of morphological and molecular methods facilitated the identification the collected earthworm species.
Results: A total of 14 earthworm species belonging to five genera and three families. The majority of these species were widely distributed across China with Megascolecidae as the dominant family. Earthworm species richness within the Baotianman National Nature Reserve increased with the altitude. However, the species diversity of earthworm at the middle altitude of 500–1,000 m was particularly abundant with a more uniform species distribution, which was consistent with the expansion pattern at the middle altitude. At the local scale, altitude exerted the greatest influence on both the species and phylogenetic diversity of earthworms, followed by soil properties and litter quality.
Conclusion: Baotianman National Nature Reserve stands out as a significant hotspot for earthworm diversity. The observe diversity index conforms to the middle height expansion pattern. The altitude, soil properties and litter quality played important roles in the formation of species diversity and phylogenetic diversity of earthworms, respectively. The study of earthworm species composition and diversity in Baotianman National Nature Reserve has enriched the species and gene bank of earthworms in China, holding significant scientific value for biodiversity conservation.
