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

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 δ 13 C and δ 15 N values of terrestrial cave animals and assessed variation in these characteristics. We then assessed the basic carbon source by analyzing the stable isotopes δ 13 C and δ 15 N. 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 δ 13 C 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 δ 13 C in cave plants. The δ 13 C and δ 15 N 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 •研究报告• 徐承香等: 贵州荔波玉屏洞穴陆生动物食物来源及营养级 1109 https://www.biodiversity-science.net 研究报告 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.

Effects of Maize–Crop Rotation on Soil Physicochemical Properties, Enzyme Activities, Microbial Biomass and Microbial Community Structure in Southwest China

“…The average annual temperature is 14.8 • C, with the lowest temperature being −3 • C in January and the highest temperature being 35 • C in July. The soil is mainly yellow loam (Chinese soil taxonomy), which is weakly acidic [32]. In the field, the soil moisture content was 20-27%, and the concentrations of soil organic carbon (SOC), nitrate-nitrogen (NO 3 − -N), ammonium-nitrogen perature is 14.8 °C, with the lowest temperature being −3 °C in January and the highest temperature being 35 °C in July.…”

“…In the field, the soil moisture content was 20-27%, and the concentrations of soil organic carbon (SOC), nitrate-nitrogen (NO 3 − -N), ammonium-nitrogen perature is 14.8 °C, with the lowest temperature being −3 °C in January and the highest temperature being 35 °C in July. The soil is mainly yellow loam (Chinese soil taxonomy), which is weakly acidic [32]. In the field, the soil moisture content was 20%-27%, and the concentrations of soil organic carbon (SOC), nitrate-nitrogen (NO3 − -N), ammonium-nitrogen (NH4 + -N) and available phosphorus (AP) were 19.5 g kg −1 , 14.5 mg kg −1 , 10.6 mg kg −1 and 17.2 mg kg −1 , respectively.…”

Lampenflora as a result of karst cave equipment for excursions

“…Процесс биодеградации не завершается даже после отмирания организмов, инкрустированных в субстрат [13]. Более того, после гибели мхов их органическое вещество, разлагаемое под действием кислот, выделяемых ими при жизни, преобразуется в плодородный почвенный слой [24], который, в свою очередь, становится привлекательным источником питательных веществ для других живых организмов [57], как и мертвое органическое вещество биопленок [23; 35].…”