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On Crete—as is common elsewhere in the Mediterranean—carbonate massifs form high mountain ranges whereas topography is lower in areas with meta‐clastic rocks. This observation suggests that differences in denudational processes between carbonate‐rich rocks and quartzofeldspathic units impart a fundamental control on landscape evolution. Here we present new cosmogenic basin‐average denudation rate measurements from both 10Be and 36Cl in meta‐clastic and carbonate bedrock catchments, respectively, to assess relationships between denudation rates, processes, and topographic form. We compare total denudation rates to dissolution rates calculated from 49 new and previously published water samples. Basin‐average denudation rates of meta‐clastic and carbonate catchments are similar, with mean values of ~0.10 mm/a and ~0.13 mm/a, respectively. The contribution of dissolution to total denudation rate was <10% in the one measured meta‐clastic catchment, and ~40% for carbonate catchments (~0.05 mm/a), suggesting the dominance of physical over chemical weathering at the catchment scale in both rock types. Water mass‐balance calculations for three carbonate catchments suggests 40–90% of surface runoff is lost to groundwater. To explore the impact of dissolution and infiltration to groundwater on relief, we develop a numerical model for carbonate denudation. We find that dissolution modifies the river profile channel steepness, and infiltration changes the fluvial response time to external forcing. Furthermore, we show that infiltration of surface runoff to groundwater in karst regions is an efficient way to steepen topography and generate the dramatic relief in carbonates observed throughout Crete and the Mediterranean.

On Crete — as is common elsewhere in the Mediterranean — carbonate massifs form high mountain ranges whereas topography is lower in areas with meta-clastic rocks. This observation suggests that differences in denudational processes between carbonate-rich rocks and quartzofeldspathic units impart a fundamental control on landscape evolution. Here we present new cosmogenic basin-average denudation rate measurements from both 10Be and 36Cl in meta-clastic and carbonate bedrock catchments, respectively, to assess relationships between denudation rates, processes, and topographic form. We compare total denudation rates to dissolution rates calculated from 49 new and previously published water samples. Basin-average denudation rates of meta-clastic and carbonate catchments are similar, with mean values of ~ 0.10 mm/a and ~ 0.13 mm/a, respectively. The contribution of dissolution to total denudation rate was &lt; 10% in the one measured meta-clastic catchment, and ~ 40% for carbonate catchments (~ 0.05 mm/a), suggesting the dominance of physical over chemical weathering at the catchment scale in both rock types. Water mass-balance calculations for three carbonate catchments suggests 40-90% of surface runoff is lost to groundwater. To explore the impact of dissolution and infiltration to groundwater on relief, we develop a numerical model for carbonate denudation. We find that dissolution modifies the river profile channel steepness, and infiltration changes the fluvial response time to external forcing. Furthermore, we show that infiltration of surface runoff to groundwater in karst regions is an efficient way to steepen topography and generate the dramatic relief in carbonates observed throughout Crete and the Mediterranean.

Chemical and mechanical properties of lithology exert a first-order control on landscape evolution and biological colonization of substrate. To quantify the influence of lithology on topography, vegetation density, and animal biodiversity, I compile lithologic, topographic, climatic, and biological data sets for mountainous regions globally. I find significant variations in the topographic steepness of regions underlain by different lithologies that, accounting for tectonic uplift, likely reflect lithologic differences in erosional resistance. These relative differences in erodibility are similar across different climate zones. To isolate the effect of lithology on vegetation and animal biodiversity, I account for the heterogeneous lithologic distribution among climate zones. I show that siliciclastic, plutonic, and, for some biological variables, metamorphic rocks exhibit elevated values of Normalized Difference Vegetation Index and tetrapod and amphibian species richness relative to carbonate rocks. These results likely reflect lithology-related variation in soil nutrients and hydrology that promote or inhibit habitat suitability. Plain Language Summary A myriad of rock types are exposed at Earth's surface, all of which have different chemical and physical properties. These differences are important because rock properties affect processes on Earth's surface that shape topography and because rocks are the base material from which most soils form. Here, I investigate how the steepness of a landscape varies based on differences in rock type and show that rock type variations can partly explain Earth's topography. I also test whether the differences in rock type that lead to variations in soil properties and water availability influence plant cover and animal richness globally. I find that limestone areas have less vegetation and lower numbers of amphibian, bird, and mammalian species. This is likely related to low water availability and nutrient content in limestone areas.

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