News
Rice Paddies
23 November 2015
A group of SWAT developers, including Drs. Balaji Narasimhan (nbalaji.iitm@gmail.com), Phil Gassman (pwgassma@iastate.edu), Jaehak Jeong (jjeong@brc.tamus.edu), Tasuku Kato (taskkato@cc.tuat.ac.jp), recently met in Tokyo to discuss and plan improvements in simulation of rice paddy irrigation, hydrology, and water quality by SWAT and APEX. For more information contact these scientists.
Short-Term Weather Forecasts
16 November 2015
Hydrologic and agricultural management models can use short-term (1-8 days) weather forecasts in SWAT format to help farmers and water authorities manage their resources. Zach Easton (zeaston@vt.edu), Andrew Sommerlot (andrewrs@vt.edu) and Daniel Fuka are developing a tool based on the NCDC/NOAA Global Forecast System to allow SWAT to project hydrology up to eight days in the future. For more information contact Dr. Easton or Dr. Fuka.
Weather Data to Simulate Climate Change Scenarios
9 November 2015
Zach Easton (zeaston@vt.edu) and Daniel Fuka (drfuka@vt.edu), are developing a tool that allows users to generate daily IPCC CMIP-5 climate change data interpolated to the precise locations of historical meteorological stations. For more information contact Dr. Easton.
Greenhouse Gas Emissions
2 November 2015
Terrestrial ecosystems can be important sources of greenhouse gas emissions (CO2, NH4, NO2), and their magnitude can be affected by land management. Zach Easton (zeaston@vt.edu), Moges Berbero (bwmoges@vt.edu) and Daniel Fuka (drfuka@vt.edu) are developing algorithms to simulate these emissions in SWAT. Cesar Izaurralde (cizaurra@umd.edu) is developing similar algorithms for inclusion in EPIC and APEX. For more information contact Dr. Easton or Dr. Izaurralde.
Global SWAT Inputs
26 October 2015
As part of a US National Science Foundation B-Cube project, Zach Easton (zeaston@vt.edu) and Daniel Fuka (drfuka@vt.edu) are developing a data “brokering” system to provide ARC SWAT users with a number of global land use, digital elevation, soils, and daily weather data bases in SWAT input formats. For more information contact Dr. Easton.
Dynamic Soils Data
19 October 2015
In most landscapes soil depth and other properties vary with landscape position. This can lead to over- and under-estimation of properties that control hydrology and plant growth. This is an especially serious problem in soil data bases like FAO in which soil map units are large. To address this problem Zach Easton (zeaston@vt.edu) and Daniel Fuka (drfuka@vt.edu) have developed a tool to adjust SWAT soil parameters (depth, saturated conductivity, available water content, sand, silt, clay, and organic matter) for landscape position. These adjusted soil parameters are then output in SWAT input format at the scale of the base DEM of the SWAT model. The tool will soon be available by contacting Dr. Easton.
Tropical Vegetation
12 October 2015
Early versions of SWAT did a poor job of simulating the leaf area dynamics of perennial tropical vegetation like forests and savannas in which drought rather than cold temperatures triggers annual leaf senescence and the onset of the rainy season stimulates their regrowth. For his work in Brazil, Michael Strauch (michael.strauch@ufz.de) developed algorithms to address this issue. It requires the user to input the beginning and ending months of the transition period at the end of the dry season when plant growth is expected to resume, as well as the soil moisture content that triggers regrowth. Functioning only at latitudes between 20ºN and 20ºS, the algorithm causes leaf area index to fluctuate realistically between the minimum and maximum LAI of the vegetation type. This improvement has recently been incorporated into SWAT2012 and SWAT+. For more information contact Dr. Strauch.
Urban Watersheds
5 October 2015
Use of SWAT for simulation of urban watersheds is increasing. Dr. Jaehak Jeong (jjeong@brc.tamus.edu) has developed algorithms to simulate the effectiveness of several conservation practices used to control water flows and improve water quality in urban areas. These can be used with both daily and sub-daily applications, and they will soon be incorporated into the SWAT Conservation Practices Tool. Contact Dr. Jeong or Dr. R. Srinivasan (r-srinivasan@tamu.edu) for more information.
Conservation Practices Tool
28 September 2015
An interface designed to help SWAT users develop scenarios involving soil and water conservation practices is under development. The tool will soon be available on the SWAT website and will allow users easily to add combinations of conservation practices to selected SWAT subbasins and HRUs in order to assess their conservation benefits by subbasin or the whole watershed. Both agricultural and urban conservation practices are included in the tool kit. Contact Dr. R. Srinivasan (r-srinivasan@tamu.edu) for more information.
QSWAT
21 September 2015
QSWAT, a QGIS Interface for SWAT has been developed by Dr. Chris George and made available with documentation and example datasets (developed by Dr. Yihun Dile) on the SWAT website. This free and open-source software will be used extensively in SWAT training, especially in developing countries where use of commercial GIS software is cost-prohibitive. For more information, see the SWAT website or contact Dr. George or Dr. Srinivasan (r-srinivasan@tamu.edu).