Inter-comparison of karst denudation measurement methods

Denudation of earth surface is the fundamental process governing the landscape and soil development. The dissolution of carbonates results in insoluble material of these rocks being available for the development of soils. Therefore, know ing rock denudation-w eathering rates is important to evaluate the time required for a certain soil to develop. There are several different methodological approaches to measure denudation rate. The must commonly used are: the exposure of rock tablets to the natural environment; the use of micro-erosion meters; measuring the concentration of cosmogenic radionuclides on exposed rocks and measuring w ater hydrochemistry to infer amount of carbonates being dissolved. Every method has pros and cons and there is no consensus on w hich method provides the more reliable denudation rates, furthermore, significant differences among methods have been reported. Therefore, this investigation aims to identify methods that could provide biased results and as w ell to report the strengths and flaw s of every method, to help researchers to select the better methods depending on the goals of their particular studies. The methods

w ill be applied at tw o different locations affected by Mediterranean climate, but w ith very different soil thickness. This approach is important to evaluate the feedback of soil thickness on denudation rates, and confirm if the conclusions from the method comparison are systematic on sites with variable characteristics. The denudation rates obtained will be used to evaluate the production of material at the studied sites to study the potential production of soil depending on denudation. This is important, since in a scenario of soil erosion in the Mediterranean region, it is important to know the potential recovery of these systems.