Evaluation of Ecosystem-Based Adaptation Measures for Sediment Yield in a Tropical Watershed in Thailand

Ecosystem-based adaptation (EbA) can potentially mitigate watershed degradation problems. In this study, various EbA measures were evaluated using a bio-physical model called the Soil and Water Assessment Tool (SWAT), in a small, forested watershed named Hui Ta Poe, in the northeastern region of Thailand. The developed watershed model was first used to investigate the effect of various degraded watersheds due to land-use changes on the sediment yield in the study area. The most degraded watershed produced an annual average sediment yield of 13.5 tons/ha. This degraded watershed was then used to evaluate the effectiveness of various EbA measures such as reforestation, contouring, filter strips, and grassed waterways in reducing the sediment yield. Under all individual and combined EbA scenarios analyzed, there was a significant reduction in sediment yield; however, the maximum reduction of 88% was achieved with a combined scenario of reforestation, grassed waterways, and filter strips. Reforestation alone was found to be the second-best option, which could reduce the sediment yield by 84%. Contouring alone was the least effective, with a reduction in sediment yield of only 23%. This study demonstrates the usefulness of implementing EbA measures for sediment management strategies to address watershed degradation, which is a severe problem across the globe.

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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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Effects of Land Use Changes on Streamflow and Sediment Yield in Atibaia River Basin—SP, Brazil

Water ◽

10.3390/w12061711 ◽

2020 ◽

Vol 12 (6) ◽

pp. 1711 ◽

Cited By ~ 1

Author(s):

Franciane Mendonça dos Santos ◽

Rodrigo Proença de Oliveira ◽

José Augusto Di Lollo

Keyword(s):

Land Use ◽

Sensitivity Analysis ◽

River Basin ◽

Sediment Yield ◽

Assessment Tool ◽

Land Use Changes ◽

Curve Number ◽

Moisture Condition ◽

Land Use Scenario ◽

Effects Of Land Use

The Soil and Water Assessment Tool (SWAT) is often used to evaluate the impacts of different land use scenarios on streamflow and sediment yield, but there is a need for some clear recommendations on how to select the parameter set that defines a given land use scenario and on what is the most appropriate methodology to change the selected parameters when describing possible future conditions. This paper reviews the SWAT formulation to identify the parameters that depend on the land use, performs a sensitivity analysis to determine the ones with larger impacts on the model results and discusses ways to consider future land use conditions. The case study is the Atibaia river basin, with 2838 km2 (São Paulo, Brazil). The parameters identified by sensitivity analysis with the largest impacts on streamflow and sediment yield were the initial curve number for moisture condition II (CN), maximum canopy storage for each land use (CANMX) and the cover and management factor (USLE_C). The identification and appropriate parameter change can provide real estimates of the magnitudes in the land use changes, which were verified in this study. Such information can be used as an instrument for proposing improvements in the basin’s environmental quality and management.

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Modeling runoff response to land-use changes using the SWAT model in the Mundaú watershed, Brazil

Journal of Environmental Analysis and Progress ◽

10.24221/jeap.5.2.2020.2828.194-206 ◽

2020 ◽

Vol 5 (2) ◽

pp. 194-206

Author(s):

Carolyne Wanessa Lins de Andrade Farias ◽

Suzana Maria Gico Lima Montenegro ◽

Abelardo Antônio de Assunção Montenegro ◽

José Romualdo de Sousa Lima ◽

Raghavan Srinivasan ◽

...

Keyword(s):

Land Use ◽

Land Use Change ◽

Sediment Yield ◽

Surface Runoff ◽

Assessment Tool ◽

Swat Model ◽

Land Use Changes ◽

Water Yield ◽

Grazing Land ◽

Runoff And Sediment Yield

Land-use change has a significant influence on runoff process of any watershed, and the deepening of this theme is essential to assist decision making, within the scope of water resources management. The study was conducted for Mundaú River Basin (MRB) using the Soil and Water Assessment Tool (SWAT) model. The study aims to assess the issue of land-use change and its effect on evapotranspiration, surface runoff, and sediment yield. Input data like land use, topography, weather, and soil data features are required to undertake watershed simulation. Two scenarios of land use were analyzed over 30 years, which were: a regeneration scenario (referring to use in the year 1987) and another scene of degradation (relating to use in the year 2017). Land use maps for 1987 and 2017 were acquired from satellite images. Overall, during the last three decades, 76.4% of forest was lost in the MRB. The grazing land increased in 2017 at a few more than double the area that existed in 1987. Changes in land use, over the years, resulted in an increase of about 37% in the water yield of MRB. Changes have led to increased processes such as surface runoff and sediment yield and in the decrease of evapotranspiration. The spatial and temporal distribution of land use controls the water balance and sediment production in the MRB.

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Do Land Use Changes Balance out Sediment Yields under Climate Change Predictions on the Sub-Basin Scale? The Carpathian Basin as an Example

Water ◽

10.3390/w12051499 ◽

2020 ◽

Vol 12 (5) ◽

pp. 1499 ◽

Cited By ~ 2

Author(s):

Paulina Orlińska-Woźniak ◽

Ewa Szalińska ◽

Paweł Wilk

Keyword(s):

Land Use ◽

Sediment Yield ◽

Assessment Tool ◽

Land Use Changes ◽

Carpathian Basin ◽

Winter Period ◽

Baseline Scenario ◽

Sediment Yields ◽

Basin Scale ◽

Yield Responses

The issue of whether land use changes will balance out sediment yields induced by climate predictions was assessed for a Carpathian basin (Raba River, Poland). This discussion was based on the Macromodel DNS (Discharge–Nutrient–Sea)/SWAT (Soil and Water Assessment Tool) results for the RCP 4.5 and RCP 8.5 scenarios and LU predictions. To track sediment yield responses on the sub-basin level the studied area was divided into 36 units. The response of individual sub-basins to climate scenarios created a mosaic of negative and positive sediment yield changes in comparison to the baseline scenario. Then, overlapped forest and agricultural areas change indicated those sub-basins where sediment yields could be balanced out or not. The model revealed that sediment yields could be altered even by 49% in the selected upper sub-basins during the spring-summer months, while for the lower sub-basins the predicted changes will be less effective (3% on average). Moreover, the winter period, which needs to be re-defined due to an exceptional occurrence of frost and snow cover protecting soils against erosion, will significantly alter the soil particle transfer among the seasons. Finally, it has been shown that modeling of sediment transport, based on averaged meteorological values and LU changes, can lead to significant errors.

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Effectiveness of Contour Farming and Filter Strips on Ecosystem Services

Water ◽

10.3390/w10101312 ◽

2018 ◽

Vol 10 (10) ◽

pp. 1312 ◽

Cited By ~ 3

Author(s):

John Gathagu ◽

Khaldoon Mourad ◽

Joseph Sang

Keyword(s):

Ecosystem Services ◽

Sediment Yield ◽

Water Conservation ◽

Assessment Tool ◽

Water Yield ◽

Model Parameters ◽

Subsequent Increase ◽

Filter Strips ◽

Filter Width ◽

Annual Sediment

The failing ecosystem services in Thika-Chania catchment is manifested in the deterioration of water quality, sedimentation of reservoirs, and subsequent increase in water treatment costs due to high turbidity. The services can be restored by implementing relevant soil and water conservation practices to enhance flow regulation and control sediment yield. The impacts of contour farming and filter strips on water and sediment yield were evaluated using Soil Water and Assessment Tool (SWAT), Texas A&M University, USA. Sediment calibration and validation was achieved using data obtained from a bathymetric survey. Model parameters were adjusted to simulate the conservation impacts of contour farming and filter strips. Results indicated the average annual sediment yield as 22 t/ha at the outlet of the catchment and average annual surface runoff of 202 mm. The simulation results showed that filter strips of 5 m width would reduce the average annual sediment yield from the catchment by 54%. The efficacy of filter strips in reducing sediment yield was observed to increase with increasing filter width. Three-meter filter strips and contour farming reduced the average annual sediment yield at catchment outlet by 46% and 36%, respectively. It was concluded that the implementation of contour farming and filters strips reduced sediments by 63% from the base value. Water yield at the sub-basin level was only influenced by contour farming. The total water yield at the catchment outlet experienced no significant change.

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Modeling Runoff and Sediment Yield in Highly Gullied Regions of Kashmir using SWAT Model: A Case Study of Lolab Watershed

Journal of the Civil Engineering Forum ◽

10.22146/jcef.55298 ◽

2020 ◽

Vol 6 (3) ◽

pp. 247

Author(s):

Dar Sarvat Gull ◽

Ayaz Mehmood Dar

Keyword(s):

Sediment Yield ◽

Assessment Tool ◽

Swat Model ◽

Management Strategies ◽

Curve Number ◽

Coefficient Of Determination ◽

Economic Productivity ◽

Environmental Consequences ◽

Global Issue ◽

Runoff And Sediment Yield

Soil erosion in highly gullied regions of Kashmir valley is a serious global issue due to its impacts on economic productivity and environmental consequences such as land disintegration and one of the most affected areas is Lolab which is flood-prone and has witnessed several disastrous floods in the past. This means assessment of hydrological behavior should be highly prioritized and the most problematic sub-basins contributing to the erosion and excessive runoff identified to formulate and apply proper management strategies. This study integrated the Soil and Water Assessment Tool (SWAT) with Arc software to simulate the runoff and sediment yield of Lolab Watershed. The method was applied due to its flexibility in inputting data requirements and the capability to model larger catchments and mountainous areas. Meanwhile, sensitivity analysis showed the most sensitive four parameters for runoff estimation with the initial soil conservation service curve number II rated to be the highest and two others were found for sediment estimation with channel erodibility factor rated highest. The calibration of the values of these sensitive parameters led to the provision of reliable NashSutcliffe (NSE) and Coefficient of determination(R2) efficiencies which makes SWAT a good analyzing tool to assess the hydrological behavior of highly gullied region and un-gauged basins of Kashmir. These factors were found to be above 0.90 for both runoff and sediment yield and the sediment yield rates were estimated using SWAT at individual sub-basin levels after which a prioritization map was prepared to determine the most problematic sub-basins in the watershed.

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Changes in Coastal Agricultural Land Use in Response to Climate Change: An Assessment Using Satellite Remote Sensing and Household Survey Data in Tien Hai District, Thai Binh Province, Vietnam

Land ◽

10.3390/land10060627 ◽

2021 ◽

Vol 10 (6) ◽

pp. 627

Author(s):

Duong H. Nong ◽

An T. Ngo ◽

Hoa P. T. Nguyen ◽

Thuy T. Nguyen ◽

Lan T. Nguyen ◽

...

Keyword(s):

Climate Change ◽

Land Use ◽

Agricultural Land ◽

Land Use Changes ◽

Management Strategies ◽

Household Survey ◽

Extreme Weather Events ◽

Agricultural Land Use ◽

Landsat 8 ◽

Land Uses

We analyzed the agricultural land-use changes in the coastal areas of Tien Hai district, Thai Binh province, in 2005, 2010, 2015, and 2020, using Landsat 5 and Landsat 8 data. We used the object-oriented classification method with the maximum likelihood algorithm to classify six types of land uses. The series of land-use maps we produced had an overall accuracy of more than 80%. We then conducted a spatial analysis of the 5-year land-use change using ArcGIS software. In addition, we surveyed 150 farm households using a structured questionnaire regarding the impacts of climate change on agricultural productivity and land uses, as well as farmers’ adaptation and responses. The results showed that from 2005 to 2020, cropland decreased, while aquaculture land and forest land increased. We observed that the most remarkable decreases were in the area of rice (485.58 ha), the area of perennial crops (109.7 ha), and the area of non-agricultural land (747.35 ha). The area of land used for aquaculture and forest increased by 566.88 ha and 772.60 ha, respectively. We found that the manifestations of climate change, such as extreme weather events, saltwater intrusion, drought, and floods, have had a profound impact on agricultural production and land uses in the district, especially for annual crops and aquaculture. The results provide useful information for state authorities to design land-management strategies and solutions that are economic and effective in adapting to climate change.

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Prioritization of Sub-Watersheds to Sediment Yield and Evaluation of Best Management Practices in Highland Ethiopia, Finchaa Catchment

Land ◽

10.3390/land10060650 ◽

2021 ◽

Vol 10 (6) ◽

pp. 650

Author(s):

Wakjira Takala Dibaba ◽

Tamene Adugna Demissie ◽

Konrad Miegel

Keyword(s):

Soil Erosion ◽

Best Management Practices ◽

Sediment Yield ◽

Soil Loss ◽

Crop Production ◽

Management Practices ◽

Assessment Tool ◽

Swat Model ◽

Sediment Yields ◽

Soil And Water

Excessive soil loss and sediment yield in the highlands of Ethiopia are the primary factors that accelerate the decline of land productivity, water resources, operation and function of existing water infrastructure, as well as soil and water management practices. This study was conducted at Finchaa catchment in the Upper Blue Nile basin of Ethiopia to estimate the rate of soil erosion and sediment loss and prioritize the most sensitive sub-watersheds using the Soil and Water Assessment Tool (SWAT) model. The SWAT model was calibrated and validated using the observed streamflow and sediment data. The average annual sediment yield (SY) in Finchaa catchment for the period 1990–2015 was 36.47 ton ha−1 yr−1 with the annual yield varying from negligible to about 107.2 ton ha−1 yr−1. Five sub-basins which account for about 24.83% of the area were predicted to suffer severely from soil erosion risks, with SY in excess of 50 ton ha−1 yr−1. Only 15.05% of the area within the tolerable rate of loss (below 11 ton ha−1yr−1) was considered as the least prioritized areas for maintenance of crop production. Despite the reasonable reduction of sediment yields by the management scenarios, the reduction by contour farming, slope terracing, zero free grazing and reforestation were still above the tolerable soil loss. Vegetative contour strips and soil bund were significant in reducing SY below the tolerable soil loss, which is equivalent to 63.9% and 64.8% reduction, respectively. In general, effective and sustainable soil erosion management requires not only prioritizations of the erosion hotspots but also prioritizations of the most effective management practices. We believe that the results provided new and updated insights that enable a proactive approach to preserve the soil and reduce land degradation risks that could allow resource regeneration.

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171 The Northeast Georgia Beef Cattle Short Course: An Eight-year Review

Journal of Animal Science ◽

10.1093/jas/skab235.166 ◽

2021 ◽

Vol 99 (Supplement_3) ◽

pp. 93-93

Author(s):

Marrissa J Blackwell ◽

Alexa Lamm ◽

R Lawton Stewart

Keyword(s):

Beef Cattle ◽

Economic Impact ◽

Assessment Tool ◽

Management Strategies ◽

Knowledge Retention ◽

Comfort Level ◽

Cattle Industry ◽

University Of Georgia ◽

Short Course ◽

Long Term Impact

Abstract A study was conducted to assess the economic impact and knowledge retention of participants that attended the Northeast Georgia Beef Cattle Short course over an eight-year period. The course is an educational program hosted by the University of Georgia Extension Service that brings evidence-based science, technology, and economic and management strategies to Georgia beef cattle producers. The short course is taught annually, lasts a full day, and offers guest speakers and demonstrations from University of Georgia faculty and staff along with industry professionals. Non-formal feedback received from participants showcases its value and supports its continuation, but little is known about how the program impacts beef production in Georgia. The goal of the study was to quantify the long-term impact of the short course while developing an assessment tool that can be used to analyze and improve the course moving forward. Qualtrics was used to distribute a survey to 308 attendees of the short course to gather information on respondents’ role in the cattle industry, knowledge of the concepts taught, comfort level utilizing what was learned, and self-reported economic impact. The response rate was 22% for this study. 41% of respondents are retired individuals, 18% were involved in agricultural production and the remainder of participants represented outside professions. 14% of respondents reported that they believed the knowledge they gained during the short course allowed them to save or gain more than $20 per head. An additional 84% reported an economic impact up to $20/head. The most frequently reported source of cattle information was extension programs, at 17%. Based on these data, Extension has a significant impact on the Georgia cattle industry. In order to further develop the program, the recommendation is made that future courses can be developed to further build relationships with cattle producers and larger operations across the state.

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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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