Effects of hydrologic conditions on SWAT model performance and parameter sensitivity for a small, mixed land use catchment in New Zealand

Abstract. The Soil Water Assessment Tool (SWAT) was configured for the Puarenga Stream catchment (77 km2), Rotorua, New Zealand. The catchment land use is mostly plantation forest, some of which is spray-irrigated with treated wastewater. A Sequential Uncertainty Fitting (SUFI-2) procedure was used to auto-calibrate unknown parameter values in the SWAT model. Model validation was performed using two data sets: (1) monthly instantaneous measurements of suspended sediment (SS), total phosphorus (TP) and total nitrogen (TN) concentrations; and (2) high-frequency (1–2 h) data measured during rainfall events. Monthly instantaneous TP and TN concentrations were generally not reproduced well (24 % bias for TP, 27 % bias for TN, and R2 < 0.1, NSE < 0 for both TP and TN), in contrast to SS concentrations (< 1 % bias; R2 and NSE both > 0.75) during model validation. Comparison of simulated daily mean SS, TP and TN concentrations with daily mean discharge-weighted high-frequency measurements during storm events indicated that model predictions during the high rainfall period considerably underestimated concentrations of SS (44 % bias) and TP (70 % bias), while TN concentrations were comparable (< 1 % bias; R2 and NSE both ~ 0.5). This comparison highlighted the potential for model error associated with quick flow fluxes in flashy lower-order streams to be underestimated compared with low-frequency (e.g. monthly) measurements derived predominantly from base flow measurements. To address this, we recommend that high-frequency, event-based monitoring data are used to support calibration and validation. Simulated discharge, SS, TP and TN loads were partitioned into two components (base flow and quick flow) based on hydrograph separation. A manual procedure (one-at-a-time sensitivity analysis) was used to quantify parameter sensitivity for the two hydrologically separated regimes. Several SWAT parameters were found to have different sensitivities between base flow and quick flow. Parameters relating to main channel processes were more sensitive for the base flow estimates, while those relating to overland processes were more sensitive for the quick flow estimates. This study has important implications for identifying uncertainties in parameter sensitivity and performance of hydrological models applied to catchments with large fluctuations in stream flow and in cases where models are used to examine scenarios that involve substantial changes to the existing flow regime.

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Modelling water, sediment and nutrient fluxes from a mixed land-use catchment in New Zealand: effects of hydrologic conditions on SWAT model performance

Hydrology and Earth System Sciences Discussions ◽

10.5194/hessd-12-4315-2015 ◽

2015 ◽

Vol 12 (4) ◽

pp. 4315-4352 ◽

Cited By ~ 2

Author(s):

W. Me ◽

J. M. Abell ◽

D. P. Hamilton

Keyword(s):

Land Use ◽

New Zealand ◽

High Frequency ◽

Swat Model ◽

Base Flow ◽

Treated Wastewater ◽

Nutrient Concentrations ◽

Flow Measurements ◽

Event Based ◽

Parameter Values

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Land Use/Cover Change and their Impacts on Streamflow in Kikuletwa Catchment of Pangani River Basin, Tanzania

Tanzania Journal of Engineering and Technology ◽

10.52339/tjet.v38i2.503 ◽

2019 ◽

Vol 38 (2) ◽

pp. 171-192

Author(s):

Upendo E. Msovu ◽

Deogratias M.M. Mulungu ◽

Joel K. Nobert ◽

Henry Mahoo

Keyword(s):

Land Use ◽

Assessment Tool ◽

Landsat Imagery ◽

Swat Model ◽

Base Flow ◽

Percentage Increase ◽

Policy Makers ◽

Future Prediction ◽

Water Assessment

Streamflow perturbation is highly prevalent in Kikuletwa catchment. However, little is known concerning land use/cover change (LULCC) with regard to streamflow perturbation in the catchment. This study aims to detect the historical and predict future LULCC and assess their impacts on streamflow amounts using the Soil and Water Assessment Tool (SWAT) model. Supervised classification of Landsat imagery data for 1985, 2000 and 2015 years was done in ERDAS 14 Imagine software. Future prediction of LULCC was done using Module for Land Use Change Evaluation (MOLUSCE) tool, a QGIS plug-in. An accuracy ranging from 79% to 82% was obtained for all steps. The results revealed that, from 1985 to 2000; 1985 to 2015; 1985 to 2030 and 1985 to 2050 the percentage of area change in cultivated land is +21.1%; +29.2%; +38.2% and +42.7%, respectively; forest is - 2.3%, -3.1%, -3.8% and -5.8%, respectively; and shrubland is -6.3%, -10%, -15.7% and - 16%, respectively. The performance of SWAT model during calibration were 0.74, 0.75, 0.51 and -0.5% for NSE, R2, RSR and PBIAS, respectively. The impacts of LULCC indicated that, between 1985 to 2000; 1985 to 2015; 1985 to 2030 and 1985 to 2050, the percentage increase in average simulated annual flow is 4.7%, 6.8%, 12.6% and 19.3%, respectively. Surface runoff increased from 25.2 mm (baseline) to 34.5 mm (36.9%); 36.2 mm (42.4%); 41.4 mm (64.3%) and 47.6 mm (88.9%), respectively. Base flow decreased marginally from 82.2 mm (baseline) to 79 mm (-3.8%); 77.8 mm (5.4%); 75.4 mm (-8.3%) and 73.9 mm (- 10.1%), respectively. Thus, apart from climate effects, streamflow perturbation in the catchment is also related to disturbances of catchment influences such as LULCC as revealed in this study. The study is useful for land planners and water resources managers and policy makers in managing resources sustainably.

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OPTIMASI PERENCANAAN PENGGUNAAN LAHAN MENGGUNAKAN SISTEM INFORMASI GEOGRAFI (SIG) DAN SOIL AND WATER ASSESSMENT TOOL (SWAT) (SUATU STUDI DI DAS CIJALUPANG, BANDUNG, JAWA BARAT)

Jurnal Ilmu Tanah dan Lingkungan ◽

10.29244/jitl.11.2.63-70 ◽

2019 ◽

Vol 11 (2) ◽

pp. 63-70

Author(s):

Erna Suryani ◽

Suria Darma Tarigan

Keyword(s):

Land Use ◽

Land Use Change ◽

Assessment Tool ◽

Swat Model ◽

Base Flow ◽

Land Resource ◽

Land Use Management ◽

Land Quality ◽

Biological Damage ◽

Run Off

The use and management of land resource which are unsuitable with its land capability will cause physical, chemical and biological-damage to the land and will disturb its hydro-orological function. The damage of land resources in a watershed needs improvement to increase its land quality. Optimal land use management planning based on its land suitability and hydrological aspects become important and need to be applied. The objectives of the study were: 1) To analyze land use change at Cijalupang Watershed, 2) To evaluate SWAT capability to predict impact of land use change on the hydrologic characteritics of the watershed, and 3) To provide land use plan based on land quality and hydrologic characteritics of the watershed. The result showed that optimizing land use management by integrating GIS and SWAT model at the Cijalupang Watershed was capable to increase land quality of the watershed. This was shown by the improvement of its land use capability to create better hydrological condition by decreasing run off 2.1 % and increasing base flow and lateral flow 0.4% and 0.4% respectively.

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A Review of SWAT Model Application in Africa

Water ◽

10.3390/w13091313 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1313

Author(s):

George Akoko ◽

Tu Hoang Le ◽

Takashi Gomi ◽

Tasuku Kato

Keyword(s):

Climate Change ◽

Land Use ◽

Water Resources ◽

Hydrological Modeling ◽

Assessment Tool ◽

Swat Model ◽

Data Availability ◽

Mitigation Measures ◽

Model Parameterization ◽

Basin Scale

The soil and water assessment tool (SWAT) is a well-known hydrological modeling tool that has been applied in various hydrologic and environmental simulations. A total of 206 studies over a 15-year period (2005–2019) were identified from various peer-reviewed scientific journals listed on the SWAT website database, which is supported by the Centre for Agricultural and Rural Development (CARD). These studies were categorized into five areas, namely applications considering: water resources and streamflow, erosion and sedimentation, land-use management and agricultural-related contexts, climate-change contexts, and model parameterization and dataset inputs. Water resources studies were applied to understand hydrological processes and responses in various river basins. Land-use and agriculture-related context studies mainly analyzed impacts and mitigation measures on the environment and provided insights into better environmental management. Erosion and sedimentation studies using the SWAT model were done to quantify sediment yield and evaluate soil conservation measures. Climate-change context studies mainly demonstrated streamflow sensitivity to weather changes. The model parameterization studies highlighted parameter selection in streamflow analysis, model improvements, and basin scale calibrations. Dataset inputs mainly compared simulations with rain-gauge and global rainfall data sources. The challenges and advantages of the SWAT model’s applications, which range from data availability and prediction uncertainties to the model’s capability in various applications, are highlighted. Discussions on considerations for future simulations such as data sharing, and potential for better future analysis are also highlighted. Increased efforts in local data availability and a multidimensional approach in future simulations are recommended.

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LUU CHECKER: A Web-based Tool to Incorporate Emerging LUs in the SWAT Model

Applied Engineering in Agriculture ◽

10.13031/aea.13295 ◽

2019 ◽

Vol 35 (5) ◽

pp. 723-731 ◽

Cited By ~ 1

Author(s):

Gurdeep Singh ◽

Dharmendra Saraswat ◽

Naresh Pai ◽

Benjamin Hancock

Keyword(s):

Land Use ◽

Management Practices ◽

Assessment Tool ◽

Urban Forest ◽

Swat Model ◽

Land Use Changes ◽

Web Based ◽

Large Size ◽

Hydrologic Response Unit ◽

User Friendly

Abstract. Standard practice of setting up Soil and Water Assessment Tool (SWAT) involves use of a single land use (LU) layer under the assumption that no change takes place in LU condition irrespective of the length of simulation period. This assumption leads to erroneous conclusions about efficacy of management practices in those watersheds where land use changes (LUCs) (e.g. agriculture to urban, forest to agriculture etc.) occur during the simulation period. To overcome this limitation, we have developed a user-friendly, web-based tool named LUU Checker that helps create a composite LU layer by integrating multiple years of LU layers available in watersheds of interest. The results show that the use of composite LU layer for hydrologic response unit (HRU) delineation in 2474-km2 L’Anguile River Watershed in Arkansas was able to capture changed LU at subbasin level by using LU data available in the year 1999 and 2006, respectively. The web-based tool is applicable for large size watersheds and is accessible to multiple users from anywhere in the world. Keywords: Land use, Web-based tool, SWAT, LUU Checker.

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Evaluating and Predicting the Effects of Land Use Changes on Hydrology in Wami River Basin, Tanzania

Hydrology ◽

10.3390/hydrology7010017 ◽

2020 ◽

Vol 7 (1) ◽

pp. 17 ◽

Cited By ~ 2

Author(s):

Sekela Twisa ◽

Shija Kazumba ◽

Mathew Kurian ◽

Manfred F. Buchroithner

Keyword(s):

Land Use ◽

Water Resources ◽

Assessment Tool ◽

Swat Model ◽

Land Use Changes ◽

Management Strategies ◽

River System ◽

Least Squares Regression ◽

Natural Forests ◽

The Impact

Understanding the variation in the hydrological response of a basin associated with land use changes is essential for developing management strategies for water resources. The impact of hydrological changes caused by expected land use changes may be severe for the Wami river system, given its role as a crucial area for water, providing food and livelihoods. The objective of this study is to examine the influence of land use changes on various elements of the hydrological processes of the basin. Hybrid classification, which includes unsupervised and supervised classification techniques, is used to process the images (2000 and 2016), while CA–Markov chain analysis is used to forecast and simulate the 2032 land use state. In the current study, a combined approach—including a Soil and Water Assessment Tool (SWAT) model and Partial Least Squares Regression (PLSR)—is used to explore the influences of individual land use classes on fluctuations in the hydrological components. From the study, it is evident that land use has changed across the basin since 2000 (which is expected to continue in 2032), as well as that the hydrological effects caused by land use changes were observed. It has been found that the major land use changes that affected hydrology components in the basin were expansion of cultivation land, built-up area and grassland, and decline in natural forests and woodland during the study period. These findings provide baseline information for decision-makers and stakeholders concerning land and water resources for better planning and management decisions in the basin resources’ use.

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Development and Integration of Sub-Daily Flood Modelling Capability within the SWAT Model and a Comparison with XAJ Model

Water ◽

10.3390/w10091263 ◽

2018 ◽

Vol 10 (9) ◽

pp. 1263 ◽

Cited By ~ 6

Author(s):

Dachen Li ◽

Simin Qu ◽

Peng Shi ◽

Xueqiu Chen ◽

Feng Xue ◽

...

Keyword(s):

Time Scale ◽

Flood Control ◽

Assessment Tool ◽

Spatial Scales ◽

Swat Model ◽

Flood Forecasting ◽

Base Flow ◽

Flood Simulation ◽

Promising Tool ◽

Daily Time

To date, floods have become one of the most severe natural disasters on Earth. Flood forecasting with hydrological models is an important non-engineering measure for flood control and disaster reduction. The Xin’anjiang (XAJ) model is the most widely used hydrological model in China for flood forecasting, while the Soil and Water Assessment Tool (SWAT) model is widely applied for daily and monthly simulation and has shown its potential for flood simulation. The objective of this paper is to evaluate the performance of the SWAT model in simulating floods at a sub-daily time-scale in a slightly larger basin and compare that with the XAJ model. Taking Qilijie Basin (southeast of China) as a study area, this paper developed the XAJ model and SWAT model at a sub-daily time-scale. The results showed that the XAJ model had a better performance than the sub-daily SWAT model regarding relative runoff error (RRE) but the SWAT model performed well according to relative peak discharge error (RPE) and error of occurrence time of peak flow (PTE). The SWAT model performed unsatisfactorily in simulating low flows due to the daily calculation of base flow but behaved quite well in simulating high flows. We also evaluated the effect of spatial scale on the SWAT model. The results showed that the SWAT model had a good applicability at different spatial scales. In conclusion, the sub-daily SWAT model is a promising tool for flood simulation though more improvements remain to be studied further.

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Comparative Analysis of Bioenergy Crop Impacts on Water Quality Using Static and Dynamic Land Use Change Modeling Approach

Water ◽

10.3390/w12020410 ◽

2020 ◽

Vol 12 (2) ◽

pp. 410 ◽

Cited By ~ 1

Author(s):

Eeshan Kumar ◽

Dharmendra Saraswat ◽

Gurdeep Singh

Keyword(s):

Water Quality ◽

Land Use ◽

Land Use Change ◽

Assessment Tool ◽

Swat Model ◽

State Agency ◽

Bioenergy Crops ◽

Marginal Land ◽

Cache River ◽

Land Area

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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SWAT-based sediment yield simulation with mining land-use change scenario in Lanuza Bay, Philippines

10.5194/egusphere-egu2020-12569 ◽

2020 ◽

Author(s):

Peter Jeffrey Maloles ◽

Adonis Gallentes ◽

Cesar Villanoy

Keyword(s):

Land Use ◽

Sediment Yield ◽

Assessment Tool ◽

Marine Protected Area ◽

Swat Model ◽

Time Lag ◽

The Philippines ◽

Marine Biodiversity ◽

Change Scenario ◽

Mining Operations

The Philippines is known for its rich marine biodiversity and is deemed as the apex of the world&#8217;s coral triangle. However, sediment yield studies and river discharge measurements in the country are sparse if not non-existent. High sediment rates have detrimental effects on water quality and consequently to coral reef health and marine biodiversity. Thus, modeling of runoff and sediment yield at a watershed level is important in assessing coral community environments.In this study, a Soil and Water Assessment Tool (SWAT) based sediment yield simulation was done for Lanuza Bay-- a site with high productivity but increasing mining activity. Two simulations were conducted. The first utilized a land-use map before January 2011 and was made to run from January 1998 to August 2018 in order to simulate a scenario in which mining operations did not occur in the area. The second simulation utilized an updated land-use map that incorporated mining sites from January 2011 to August 2018.SWAT model results indicate that slope class was the primary determinant of erosion rates (slope band > 20%). The study suggests that consecutive precipitation occurrences affected soil erodability and induced a time lag between precipitation and sediment yield peaks. The highest contributors to sediment yield at a sub-basin level were identified to be areas adjacent to or coinciding in mining or excavation sites. Comparing the scenarios with and without mining, mining contributed to 4% of the increase in the watershed&#8217;s total annual sediment yield.Qualitative and historical validation shows reasonable agreement between simulated values and satellite images. The output of this study can be used as a science-based reference in crafting laws and policies for land-use management and Marine Protected Area (MPA) planning.

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Post-validation of SWAT model in a coastal watershed for predicting land use/cover change impacts

Hydrology Research ◽

10.2166/nh.2015.222 ◽

2015 ◽

Vol 46 (6) ◽

pp. 837-853 ◽

Cited By ~ 14

Author(s):

Harsh Vardhan Singh ◽

Latif Kalin ◽

Andrew Morrison ◽

Puneet Srivastava ◽

Graeme Lockaby ◽

...

Keyword(s):

Water Quality ◽

Land Use ◽

Suspended Solids ◽

Assessment Tool ◽

Organic Phosphorus ◽

Swat Model ◽

Coastal Watershed ◽

Water Quality And Quantity ◽

Water Assessment ◽

Total P

Watershed models are typically calibrated and validated with the same land use and land cover (LULC) dataset and later used in assessing impacts of changing LULC, such as urbanization, on hydrology and/or water quality. However, their performance in predicting water quality/quantity in response to changing LULC is rarely assessed. The main objective of this paper was to explore the performance of the soil and water assessment tool (SWAT) in predicting water quality and quantity in response to changing LULC in a coastal watershed in Alabama, USA. Using the 1992 LULC as the input, the model was calibrated and validated for flow for the period 1990–1998, and for total suspended solids (TSS), nitrate (NO3−), and organic phosphorus for the period 1994–1998 at several sites within the watershed. The model was then driven with the 2008 LULC data and its performance in predicting flow and TSS, NO3−, and total-P loads during the period 2008–2010 was evaluated (post-validation). SWAT showed good performance in predicting changes in flow and water quality during the post-validation period. The study also highlighted the importance of using the most up-to-date LULC data for effectively predicting the impacts of LULC changes on water quality.

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