High K and Ca Chemical Erosion Triggered by Physical Erosion in a Watershed of the High Himalaya of Nepal

The Khudi river in Nepal is an example of a basin undergoing intense physical erosion by landslide under very wet monsoonal conditions. Although under such a regime, dissolved element concentrations are expected to during the monsoon, we observe marked increases in dissolved K and Ca during flood events. These peaks in K and Ca concentrations are well correlated with increases of suspended load by an order of magnitude. The data suggest that release of K and Ca is enhanced by physical erosion and rock disaggregation events during sediment transfer.