Advances in water resources assessment with SWAT—an overview

Abstract

This paper introduces a Special Issue containing 10 research papers which present current applications of the Soil and Water Assessment Tool (SWAT) for water resources assessment. First, an overview of selected, recently published papers with application of SWAT is given. The papers address the following topics: nutrients and related best management practices (BMPs); sediments and related BMPs; impoundment and wetlands; irrigation; bioenergy crops; climate change impact; and land-use change impacts. Then, papers from this Special Issue are briefly described, covering the themes: surface runoff and sediments; non-point source pollution; surface water and groundwater; impacts of climate and land-use change; and large-scale SWAT applications. The presented model applications of SWAT were conducted across a variety of spatial scales, physiographic regions and climatic zones. This collection of papers demonstrates that applications of SWAT for water resources assessment are growing in number and cover drainage basins in many regions worldwide.

Rice Intensification in a Changing Environment: Impact on Water Availability in Inland Valley Landscapes in Benin

“…As one of the various tools developed, the Soil and Water Assessment Tool (SWAT) model [28] was applied in many fields to assess water quantity and quality [2,[29][30][31][32][33][34]. Likewise, the important and unrestricted application of the model for climate change and land use scenarios simulation was also confirmed by recent reviews of SWAT literature [35,36].…”

“…Although substantial advancements were made in assessing land use and climate change impacts on water resources in many countries [35], few studies have assessed in Benin how the long-term patterns in watershed's hydrological components could be influenced. Most of the existing research was conducted on evaluating the future impacts of climate or land use changes at larger spatial scales and specifically focused on rainfall-runoff processes [34], groundwater resources [37], erosion-related degradation processes based on sediment yields in the upper Ouémé watershed [2,5] and upland crop production [38][39][40].…”

Assessment of Three Long-Term Gridded Climate Products for Hydro-Climatic Simulations in Tropical River Basins

“…SWAT is usually executed at a daily time step for continuous simulations [36], typically with a minimum climatic dataset consisting of daily precipitation, maximum temperature and minimum temperature. The model has been applied for an extensive range of ecohydrological problems and scenarios worldwide for watershed scales ranging from <1 km 2 to entire continents (e.g., see reviews by Gassman et al [48,49]; Bressiani et al [25]; Gassman and Wang [50]; and Krysanova and White [51]). The model has also been used successfully for several hydrology and pollutant transport studies conducted in Malaysia [40,[52][53][54][55].…”

Case Study: Effect of Climatic Characterization on River Discharge in an Alpine-Prealpine Catchment of the Spanish Pyrenees Using the SWAT Model

“…The daily data series (synthetic station) were generated from observed daily data for an intermediate point of the headwater (Figure 1) at an altitude of 2000 m a.s.l., since it is from this altitude that the precipitation altitudinal gradient decreases to almost half. For this purpose, temperature (R tmp ) and precipitation (R pcp ) ratios relating to the estimated altitudinal climatic gradients and the difference in elevations between observed and generated climatic stations were calculated and added to the daily observed data following Equations (1) and (2). In the case of precipitation, the ratio was calculated from the average annual precipitation over a ten-year period (∆ pcp ) and the expected average annual precipitation in relation to the precipitation altitudinal gradient (G pcp ) and the difference altitude between the observed (h o ) and the synthetic data (h s ).…”

“…Therefore, hydrological studies are necessary to implement basin management plans to protect water resources. Contemporary catchment models have become very useful tools and the Soil and Water Assessment Tool (SWAT) model is one of the most widely used of the many catchment models available (e.g., [2]). Since it has been continuously improved over the last 30 years, it has gained international acceptance as an interdisciplinary tool suitable for application at different scales of catchments with varying degrees of biophysical and climatic settings (e.g., [3]).…”