Cosmogenic nuclide and solute flux data from central Cuban rivers emphasize the importance of both physical and chemical mass loss from tropical landscapes

Abstract. We use 25 new measurements of in situ produced cosmogenic 26Al and 10Be river sand, paired with estimates dissolved load flux water, to characterize the processes pace landscape change central Cuba. Long-term erosion rates inferred from concentrations quartz extracted Cuban sand range 3.4–189 Mg km−2 yr−1 (mean 59, median 45). Dissolved loads (10–176 yr−1; mean 92, 97), calculated stream solute modeled runoff, exceed measured cosmogenic-10Be-derived 18 23 basins. This disparity mandates that this environment landscape-scale mass loss is not fully represented by nuclide measurements. The / ratios are lower than expected for steady-state exposure or 16 24 samples. Depressed occur many basins have greatest between (high) (low). consistent presence a deep, mixed, regolith layer providing extended storage times on slopes and/or burial during fluvial transport. River water chemical analyses indicate high underlain at least part evaporitic rocks rapidly dissolve. Our data show when assessing humid tropical landscapes, accounting contribution rock dissolution depth particularly important. In such warm, wet climates, mineral can meters below surface, beyond penetration most cosmic rays thus production nuclides. suggest importance estimating fluxes measuring nuclides better understand transfer basin scale.