生物多样性 ›› 2021, Vol. 29 ›› Issue (8): 1108-1119.DOI: 10.17520/biods.2021086

• 研究报告:动物多样性 • 上一篇    下一篇

贵州荔波玉屏洞穴陆生动物食物来源及营养级

徐承香(), 赵璐, 杜维锋, 张思强, 吴永英, 周非   

  1. 贵州师范大学生命科学学院, 贵阳 550025
  • 收稿日期:2021-03-09 接受日期:2021-05-07 出版日期:2021-08-20 发布日期:2021-07-28
  • 通讯作者: 徐承香
  • 作者简介:* E-mail: xcxiang119@163.com
  • 基金资助:
    贵州省科技计划项目(黔科合基础〔2017〕1416);国家自然科学基金(31660152);贵州省科技计划项目(黔科合平台人才〔2017〕5726)

Food sources and trophic levels of terrestrial cave fauna in Yuping Town, Libo County, Guizhou Province

Chengxiang Xu(), Lu Zhao, Weifeng Du, Siqiang Zhang, Yongying Wu, Fei Zhou   

  1. School of Life Sciences, Guizhou Normal University, Guiyang 550025
  • Received:2021-03-09 Accepted:2021-05-07 Online:2021-08-20 Published:2021-07-28
  • Contact: Chengxiang Xu

摘要:

洞穴是“极端地下生物多样性”的聚集地, 为了揭示洞穴陆生动物的食物来源以及营养级关系, 本文于2016年10月对贵州荔波玉屏镇的3个代表性洞穴内的陆生动物进行调查, 应用13C和15N稳定同位素方法, 分析了洞内陆生动物和基础碳源的δ13C、δ15N值变化特征, 探究了各动物类群的营养级位置以及不同的基础碳源对动物的食物源的贡献率。结果表明: 洞穴植物的δ13C值范围为-38.25‰ ± 0.95‰至-29.44‰ ± 0.49‰, 土壤有机质δ13C值范围为-32.73‰ ± 0.03‰至-24.68‰ ± 0.41‰, 大部分不在洞穴植物的δ13C变化范围内。洞穴动物δ13C、δ15N值范围分别为-34.22‰ ± 0.39‰至-14.83‰ ± 0.78‰、1.86‰ ± 0.20‰至16.43‰ ± 0.05‰, 表现出较大的种(或类群)间差异。IsoSource软件估算结果表明, 洞穴土壤有机质对78.3%动物类群的食物源的贡献率高于植物。荔波玉屏洞穴消费者的营养级范围为1.01-5.32, 其中, 巨蚓科、螺类、潮虫科、马陆、大蚊科、夜蛾科主要处于第2营养层次; 蚰蜒科、蚁蛉科(幼虫)、蝙蝠处于第3营养层次; 蜚蠊科处于第2-3营养层次; 驼螽科、蠼螋科处于第2-4营养层次; 蜘蛛处于第2-5营养层次, 跨3个营养级。综上认为, 洞穴土壤有机质是洞穴消费者的主要食物基础。大部分同一类群的动物在洞穴中所处的营养级位置较稳定, 少部分同属于一个类群的动物在不同洞穴或同一洞穴不同光带所处的营养级位置有差异。

关键词: 稳定同位素, 营养级, 食物源, 洞穴动物, 荔波, 贵州

Abstract

Aims:Karst caves are a gathering place for biodiversity in belowground extreme environments, but little is known about their food web structure. We investigated this by assessing the food sources and trophic levels of terrestrial cave fauna in Yuping Town, Libo County, Guizhou Province. We further documented cave biodiversity resource utilization to provide important reference data to inform conservation of karst ecosystems.

Methods: We investigated terrestrial cave animals in three representative caves in Yuping Town, Libo County, Guizhou Province in October 2016. In each cave system, we recorded δ13C and δ15N values of terrestrial cave animals and assessed variation in these characteristics. We then assessed the basic carbon source by analyzing the stable isotopes δ13C and δ15N. We then estimated the contribution rates of five types of basic carbon sources to terrestrial consumers using IsoSource software, and explored the trophic level of each faunal species in each cave.

Results: The δ13C value of cave plants ranged from -38.25‰ ± 0.95‰ to -29.44‰ ± 0.49‰, while that of soil organic matter ranged from -32.73‰ ± 0.03‰ to -24.68‰ ± 0.41‰. Most of these values were outside the change interval of δ13C in cave plants. The δ13C and δ15N values of cave fauna ranged from -34.22‰ ± 0.39‰ to -14.83‰ ± 0.78‰ and from 1.86‰ ± 0.20‰ to 16.43‰ ± 0.05‰, respectively, suggesting large differences among species and groups. The 78.3% contribution rate of soil organic matter to cave fauna was higher than that of the primary productivity of plants. The trophic level of cave consumers in Yuping Town, Libo County ranged from 1.01 to 5.32. Megascolecidae, snails, Oniscidae, horseshoes, Tipulidae, and Noctuidae were mainly classified as primary consumers into the second trophic level; Scutigeridae, Myrmeleontidae (larvae), and bats were classified into the third trophic level; Blattidae were classified into the second to third trophic level; Rhaphidophoridae and Labiduridae were classified into the second to fourth trophic level; and spiders spanned three trophic levels, being classified into the second to fifth trophic level.

Conclusions: Organic matter in cave soil is the main food source for cave consumers. Most cave fauna in the same taxonomic group had a consistent trophic level in caves, though some fauna belonging to the same taxa had different trophic levels in different caves or in different light zones of the same cave.

Key words: stable isotope, trophic level, food source, cave fauna, Libo County, Guizhou Province