Assessment Of The Impact Of Surface Water Resource Changes On Urban Agriculture In Da Lat

Abstract

The variability of surface water resources has become one of the major challenges for urban agriculture development in highland cities, particularly in Da Lat, Vietnam, where water plays a crucial role in commercial agricultural production. This study aims to assess the impacts of surface water resource changes on urban agriculture in Da Lat in recent years, through streamflow calculations and surveys of 300 farming households. Results indicate that surface water in Da Lat during 1993–2024 exhibits strong seasonal fluctuations, with 75–80% of streamflow occurring in the rainy season and only 20–25% in the dry season. Dry-season flow shows a declining trend, with record lows in 2011, 2015, and 2019. Household surveys reveal increasing exploitation pressures, mainly due to urbanization (mean score >4.0), irrigation demand, and intensive farming practices (scores 3.7–3.9). Dry-season droughts (56% of households reporting increases) and declining water quality (34.7%) emerge as key challenges. The most significant impact is increased production costs (47.7%), while crop yields largely remain stable (75%) due to seasonal adjustments and technical investments. These findings indicate that surface water variability is heightening the risk of shortages and increasing costs, threatening the sustainability of urban agriculture.