Geochemical characterization of clastic sediments sheds light on energy sources and on alleged anthropogenic impacts in cave ecosystems

Abstract Caves are usually oligotrophic ecosystems, where the organic matter represents a limiting factor to hypogeal community and sediments often significant energy source. With view identifying input influencing ecological processes occurring in caves, as well potential alteration sources of natural equilibriums, geochemical features several typologies clastic from Pertosa-Auletta Cave (Italy) were investigated. The collected sediments, analyzed for number chemical (organic matter, Al, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, P, Pb, S, Si, Sr, Ti, V, Zn concentrations) mineralogical (quartz, calcite, dolomite, clay minerals) characteristics, showed different composition. Overall, their origin is supposed be allochthonous, related important fluviokarst activities interesting cave past, whereas abundance calcitic dolomitic compounds can autochthonous, being carbonate main host rock. highest concentrations together with C, N, S Zn, highlighted one sample composed mainly bats guano, revealed an bioavailable pollutant accumulation, anthropogenic origin.