Monthly Time-Step Erosion Risk Monitoring of Ishmi-Erzeni Watershed, Albania, Using the G2 Model

摘要: In this study, soil erosion was mapped in Ishmi-Erzeni watershed, Albania, using the G2 model. The model has been proposed as an agri-environmental service by Global Monitoring for Environment and Security (GMES) initiative (now Copernicus programme). Based on principles of Universal Soil Loss Equation (USLE), provides maps actual loss at a monthly time-step. main innovations with regard to previous USLE family models are follows: introduction ‘storm factor’, which differentiates rainfall erosivity (R factor) per month when detailed rain intensity records not available; use standardised biophysical parameters derived from satellite image time series combination land information calculating vegetation retention factor (denoted here V factor, corresponding C USLE); imagery new namely slope intercept I factor), expresses landscape feature alterations, thus functioning corrective topographic influence T length steepness (LS) USLE). originally implemented cross-border Strymonas river basin island Crete after revision; both cases encouraging results. follows data-driven methodology, while providing alternatives all estimations moderate data requirements. For application watershed (covering 2200 km2), were collected ten weather stations, properties measured sampling 47 locations. Vegetation layers downloaded GMES portal, extracted Landsat-7 TM image. Finally, terrain calculated 250-m digital elevation (DEM) area. showed have erosion, mean annual estimated be 6.5 t/ha; however, 18 % area is facing risk removal more than 10 t/ha, considered sustainable threshold Albania. Winter months appear most risky, contributing substantially rate (i.e. between 4 12 % each). Areas coniferous mixed forests, together mountainous agricultural land, risky uses. conclusion, proved useful efficient predicting time-steps uses watershed. Future research will focus Albania-wide mapping task,