Anthropization level of Lascaux Cave microbiome shown by regional‐scale comparisons of pristine and anthropized caves

Abstract

Limestone areas across the world develop karstic caves, which are populated by a wide range of macro‐ and microorganisms. Many of these caves display Paleolithic art or outstanding speleothems, and in the last century they have been subjected to anthropization due to touristic management and intense human frequentation. Despite their cultural importance and associated conservation issues, the impact of anthropization on cave biodiversity is not known. Here, we show that anthropization is associated with specific cave biota modifications. We compared diversity in four pristine caves, four anthropized show caves, and the iconic Lascaux Cave with even stronger anthropization. The predominant microbial higher taxa were the same in all caves, but the most anthropized cave (Lascaux) was unique as it differed from the eight others by a higher proportion of Bacteroidetes bacteria and the absence of Euryarchaeota and Woesearchaeota archaea. Anthropization resulted in lower diversity and altered community structure for bacteria and archaea on cave walls, especially in Lascaux, but with a more limited effect on microeukaryotes and arthropods. Our findings fill a key gap in our understanding of the response of karstic communities to anthropization, by revealing that tourism‐related anthropization impacts on the prokaryotic microbiome rather than on eukaryotic residents, and that it shapes cave biota irrespective of cave natural features.

Conservation State of Two Paintings in the Santa Margherita Cliff Cave: Role of the Environment and of the Microbial Community

“…The microbial survey carried out in the Santa Margherita's cave was aimed to evaluate the microbial community harboured by this unique environment on one hand, and on the other hand, to give insights about the possible role of microorganisms as a potential risk for paintings conservation. Similarly to what was previously unveiled in related cave environments (Ma et al 2015;Portillo et al 2008;Pavlik et al 2018;Yasir 2018;Alonso et al 2019), the bacterial community of both east and west walls was represented by Firmicutes, Proteobacteria, Bacteroidetes, Actinobacteria, Cyanobacteria, and Gammatimonodota phyla (Fig. 8a).…”

Caving Impacts on Cave Microbial Diversity: Case Study of Morca Cave, Turkey

“…Other studies also reported that decrease of microbial diversity in caves can be caused by anthropogenic activities inside or around the cave ( Alonso et al 2019). Anincrease in the levels of CO 2 inside the cave ecosystem during expedition is reported in cave opened for tourism.…”

Human activities’ impacts on cave microbial diversity: perspectives for cave microbial diversity conservation

“…In many countries, the show caves are among their main economic revenues. We can enumerate the Rouffignac Caves in France opened in 1959 and visited by up to 500 visitors per day [38]. Further, more than 250,000 of visitors were reported to enter the Gongo Cave, located in the Pacitan regency in Indonesia, per year which contributes to more than 200,000 US$ per year in this regency economy [39].…”

“…Limit of organic matter, stable temperature, high humidity, and low or total darkness are the best environmental conditions for the biodiversity of these ecosystems. However, diverse external factors can affect these sensitive conditions thereby impacts on the life of the biogenic part of caves as it demonstrated by [38]. Microorganisms are among the main cave biodiversity and they can appear as visible mats as well as invisible biofilms on cave walls, sediments, and pools [4].…”