Attribution of changes in the water balance of a tropical catchment to land use change using the SWAT model

Researchers and federal and state agency officials have long been interested in evaluating location-specific impact of bioenergy energy crops on water quality for developing policy interventions. This modeling study examines long-term impact of giant miscanthus and switchgrass on water quality in the Cache River Watershed (CRW) in Arkansas, United States. The bioenergy crops were simulated on marginal lands using two variants of a Soil and Watershed Assessment Tool (SWAT) model. The first SWAT variant was developed using a static (single) land-use layer (regular-SWAT) and for the second, a dynamic land-use change feature was used with multiple land use layers (location-SWAT). Results indicated that the regular-SWAT predicted larger losses for sediment, total phosphorus and total nitrogen when compared to location-SWAT at the watershed outlet. The lower predicted losses from location-SWAT were attributed to its ability to vary marginal land area between 3% and 11% during the 20-year modeling period as opposed to the regular-SWAT that used a fixed percentage of marginal land area (8%) throughout the same period. Overall, this study demonstrates that environmental impacts of bioenergy crops were better assessed using the dynamic land-use representation approach, which would eliminate any unintended prediction bias in the model due to the use of a single land use layer.

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The Impacts of Different Land Use Patterns on Water Volume in the Xixian Watershed, China

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.737.728 ◽

2015 ◽

Vol 737 ◽

pp. 728-731 ◽

Cited By ~ 1

Author(s):

Yuan Yuan Han ◽

Tao Cai

Keyword(s):

Land Use ◽

Time Series ◽

Land Use Change ◽

River Basin ◽

Water Conservation ◽

Swat Model ◽

Water Volume ◽

Huaihe River Basin ◽

Huaihe River ◽

Soil And Water

In this study, Soil and Water Assessment Tool (SWAT) model was used to simulate land-use change effects on water quantity in the upper Huaihe river basin above the Xixian hydrological controlling station with a catchment area of 10,190 km2 by the use of three-phase (1980s、1990s、2000s) land-use maps, soil type map (1:200000), 1980 to 2008 daily time series of rainfall from the upper Huaihe river basin. On the basis of the simulated time series of daily runoff, land-use change effects on spatio-temporal change patterns of runoff coefficients and runoff modules were investigated. The results revealed that under the same condition of soil texture and terrain slope the advantage for runoff generation and the sensitivity of rainfall-runoff relationship to rainfall descended by farmland, paddy field, woodland.The outputs could provide important references for soil and water conservation and river health protection in the upper stream of Huaihe river.

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Impact of Arable Land to Grassland Conversion on the Vegetation-period Water Balance of a Small Agricultural Catchment (Němčický Stream)

Soil and Water Research ◽

10.17221/7/2010-swr ◽

2010 ◽

Vol 5 (No. 4) ◽

pp. 128-138 ◽

Cited By ~ 2

Author(s):

P. Kovář ◽

D. Vaššová

Keyword(s):

Land Use ◽

Land Use Change ◽

Water Balance ◽

Surface Runoff ◽

Arable Land ◽

Vegetation Period ◽

Water Balance Components ◽

Total Runoff ◽

Grassland Conversion ◽

Pronounced Reduction

This paper presents results of decadal (10-day) water balance simulations for the vegetation periods (April to October) of 2001 (normal year), 2002 (wet year) and 2003 (dry year) in the Němčický Stream experimental catchment (3.52 km<sup>2</sup>). The catchment is a typical agricultural area with a large extent of arable land. This paper shows that the model used (WBCM) is capable of reliably simulating decadal water balance components for the actual land use. The same model is then used to estimate water balance changes brought about when 10% of arable land has been transformed into permanent grassland. It is shown that this land use change results in a pronounced reduction of surface runoff and an increase in subsurface storage over the vegetation periods of all three years. The vegetation period groundwater runoff was only enhanced in the wet year, while the total runoff was reduced in all three years. 

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Dynamic Land Use Change Prediction and Analysis of Its Impacts on Streamflow for Dabus Watershed, Upper Blue Nile Basin

10.20944/preprints202104.0393.v1 ◽

2021 ◽

Author(s):

Neseredin Bashawal Mangel ◽

Fitsum Berhe

Keyword(s):

Land Use ◽

Land Use Change ◽

Swat Model ◽

Model Performance ◽

Test Analysis ◽

Blue Nile Basin ◽

The Future ◽

Kappa Value ◽

Change Prediction ◽

Basin System

Based on the recorded watershed characteristics, the future conditions on the basin system can be predicted using a different method. In this study, dynamic land-use change and its impacts on the streamflow for the Dabus watershed were predicted using ANN-CA based method. The model performance for accurate prediction of the future land-use change on the Dabus River watershed has been checked by validation of the simulated value with the actual value, hence the overall kappa value (k) = 0.83 for the simulated 2016-LULC validated with actual 2016-LULC. Then, 2026-LULC was predicted based on the 2004 and 2009-LULC. The streamflow for the case of 2004 and 2009-LULC has been simulated using the SWAT model. The value of NSE = 0.87 and 0.90 was attained during validation of simulated streamflow for 2004 and 2009-LULC data cases, respectively. The agreement of simulated value of streamflow with the observed data is indicated as R2 = 0.91 and 0.96 for 2004-LULC and 2009-LULC. The effects of the dynamic land-use change on streamflow for the predicted land use(2026-LULC) catchment were evaluated by T-test analysis. Hence, T-stat =0.04 and -0.002 in the case of simulated streamflow used 2004-LULC and 2009-LULC, respectively compared with simulated value using 2026-LULC.

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Forecasting land-use change and its impact on the groundwater system of the Kleine Nete catchment, Belgium

Hydrology and Earth System Sciences Discussions ◽

10.5194/hessd-4-4265-2007 ◽

2007 ◽

Vol 4 (6) ◽

pp. 4265-4295 ◽

Cited By ~ 10

Author(s):

J. Dams ◽

S. T. Woldeamlak ◽

O. Batelaan

Keyword(s):

Climate Change ◽

Land Use ◽

Land Use Change ◽

Water Balance ◽

Groundwater Level ◽

Balance Model ◽

Groundwater Model ◽

Water Balance Components ◽

Groundwater System ◽

The Impact

Abstract. Land-use change and climate change, along with groundwater pumping are frequently indicated to be the main human-induced factors influencing the groundwater system. Up till now, research has mainly been focusing on the effect of the water quality of these human-induced changes on the groundwater system, often neglecting changes in quantity. The focus in this study is on the impact of land-use changes in the near future, from 2000 until 2020, on the groundwater quantity and the general hydrologic balance of a sub-catchment of the Kleine Nete, Belgium. This study tests a new methodology which involves coupling a land-use change model with a water balance model and a groundwater model. The future land-use is modelled with the CLUE-S model. Four scenarios (A1, A2, B1 and B2) based on the Special Report on Emission Scenarios (SRES) are used for the land-use modelling. Water balance components, groundwater level and baseflow are simulated using the WetSpass model in conjunction with a MODFLOW groundwater model. Results show that the average recharge slowly decreases for all scenarios, the decreases are 2.9, 1.6, 1.8 and 0.8% for respectively scenario A1, A2, B1 and B2. The predicted reduction in recharge results in a small decrease of the average groundwater level, ranging from 2.5 cm for scenario A1 to 0.9 cm for scenario B2, and a reduction of the total baseflow with maximum 2.3% and minimum 0.7% respectively for scenario A1 and B2. Although these average values do not indicate significant changes for the groundwater system, spatial analysis of the changes shows the changes are concentrated in the neighbourhood of the major cities in the study areas. It is therefore important for spatial managers to take the groundwater system into account for reducing the negative impacts of land-use and climate change as much as possible.

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Dampak Perubahan Tataguna Lahan Terhadap Keseimbangan Air Wilayah Pulau Seram. Studi Kasus : Das Way Pia Di Kabupaten Maluku Tengah, Provinsi Maluku

Agrologia ◽

10.30598/a.v1i1.296 ◽

2018 ◽

Vol 1 (1) ◽

Author(s):

Semuel Laimeheriwa

Keyword(s):

Land Use ◽

Land Use Change ◽

Water Balance ◽

Soil Water ◽

Global Radiation ◽

Mathematical Formulation ◽

Computer Code ◽

Water Balance Components ◽

Current Time ◽

Run Off

This research was conducted to estimate the values of parameters which described the physical characteristics of catchments area and monthly water balance components, and understand the sensitivity of the water balance components to change in the parameter value due to the physical changes occurring in Way Pia catchments area, Ceram Island. The method used involved calculation of the regional water balance in the current time (normal) and during the time of land use change, using an evapoclimatonomy model. The main model inputs were monthly rainfall, global radiation and run off. Analyses of data were conducted with five steps as follows : (1) mathematical formulation of the evapoclimatonomy model, (2) algorithm formation and transfer to computer code, (3) establishment of parameters and calibration, (4) validation of model, and (5) experimentation of model. The current physical conditions of Way Pia catchments area were characterized by: average of parameter value of albedo, a = 0,16; rainfall threshold, Pn = 100 mm; surface run off ratio, np = 0,23; evapority, ep = 0,42; measure of soil water loss from sub surface, vN = 0,12; and measure of evapotranspiration of soil water from sub surface, vE = 0,20. Model output of the current water balance consisted of annual value of soil moisture, m = 272 mm; total evapotranspiration, E = 1393 mm, and total run off, N = 920 mm. The land use change in the form of land clearing will increase the parameter values of a and np, which affect on increasing of direct run off (N') of 13% as compared to current conditions.

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