Links Between Land Surface Characteristics and near-Surface Accumulations of Dust, Soluble Salts, Nitrate-Nitrogen, and Carbonate in the Southern Fry Mountains, Mojave Desert, USA

Arid mountains are geomorphically distinct areas on the desert landscape because of their elevational range, complex topography, and shear extent. Studies focusing on the link between geomorphology and soils in these landforms, however, are nearly absent in the literature. The current project addresses this paucity of data by examining landforms of the southern Fry Mountains, Mojave Desert, California. Four major landforms were distinguished on the basis of morphometry and land surface characteristics (LSC): mountaintop/bench, mountainflat, mountainflank, and mountainbase. Interpolated maps from 65 soil pits across the study site show that dust and soluble salt distributions are correlated with prevailing wind direction suggesting the mountain range effectively traps eolian sediment. Soils in the upper meter of these mountains have accumulated on average 41 kg m^-2 dust, 172 g m^-2 soluble salts, 3.3 g m^-2 NO₃^--N, and 79 kg m^-2 carbonate reaching maximum concentrations of 156 kg m^-2, 1800 g m^-2, 43 g m^-2 and 398 kg m^-2 on windward sides of the range, respectively. We measured upper meter concentrations of soluble salts (20 kg m^-2), NO₃^--N (930 g m^-2), and carbonate (390 kg m^-2) in Soggy Lake, a nearby playa upwind from these mountains and the likely source of these accumulations. LSC variables of the four major landforms in the mountains were used to interpret the distributions of these accumulations. This work demonstrates that arid mountains can accumulate and store appreciable quantities of dust, soluble salts, NO₃^--N, and carbonate and are thus important to the overall geomorphology and distribution of nutrients in the region.