Establishing a framework of a watershed-wide screening tool to support the development of watershed-based flood protection plans for low-lying coastal communities

Flood risk analysis is the instrument by which floodplain and stormwater utility managers create strategic adaptation plans to reduce the likelihood of flood damages in their communities, but there is a need to develop a screening tool to analyze watersheds and identify areas that should be targeted and prioritized for mitigation measures. The authors developed a screening tool that combines readily available data on topography, groundwater, surface water, tidal information for coastal communities, soils, land use, and precipitation data. Using the outputs of the screening tool for various design storms, a means to identify and prioritize improvements to be funded with scarce capital funds was developed, which combines the likelihood of flooding from the screening tool with a consequence of flooding assessment based on land use and parcel size. This framework appears to be viable across cities that may be inundated with water due to sea-level rise, rainfall, runoff upstream, and other natural events. The framework was applied to two communities using the 1-day 100-year storm event: one in southeast Broward County with an existing capital plan and one inland community with no capital plan.

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Catchment scale land use optimisation using genetic algorithm to mitigate acute diffuse pollution

10.5194/egusphere-egu2020-20008 ◽

2020 ◽

Author(s):

Vaida Suslovaite ◽

James Shucksmith ◽

Vanessa Speight

Keyword(s):

Genetic Algorithm ◽

Land Use ◽

Drinking Water ◽

Surface Water ◽

High Risk ◽

Diffuse Pollution ◽

Mitigation Measures ◽

Rainfall Runoff ◽

Pollutant Concentrations ◽

Receiving Water

<p>Diffuse pollution resulting from rainfall runoff processes is known to adversely affect surface water quality, including in areas where surface water is used for drinking water supply. Designing and implementing targeted mitigation measures to reduce peak concentrations of specific contaminants such as pesticides is challenging due to the spatial and temporal variability of rainfall-runoff processes. Receiving water pollutant concentrations are a function of rainfall processes, catchment characteristics, receiving water conditions and the locations of pollution sources (i.e. spatial distribution of &#8216;high risk&#8217; land use types). Past work has developed a validated, travel time based, physically distributed model used to predict metaldehyde levels after a rainfall event accounting for variations in rainfall and distribution of land use. However, targeted field scale mitigation measures require an understanding of how different land use distributions affect pollutant concentrations in river water over a representative number of rainfall events.&#160;</p><p>In this study, an inverse modelling approach is adopted in which the metaldehyde model is used in conjunction with spatial and temporal distributions of rainfall data spanning over a number of years. Genetic algorithm(GA) technique is used to carry out land use optimisation. This technique can be used to determine distributions of land use that minimises the total number of predicted hours that metaldehyde levels exceed the EU and UK threshold of 0.1 &#956;g L&#8722;1 for pesticides in drinking water. The approach can also be used to show how the removal of specific high risk fields will affect metaldehyde concentrations as well as rank and prioritise specific catchment areas. This can be used to inform catchment management groups of the most effective locations for the implementation of mitigation measures.</p>

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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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A cost-effectiveness analysis of water security and water quality: impacts of climate and land-use change on the River Thames system

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2012.0413 ◽

2013 ◽

Vol 371 (2002) ◽

pp. 20120413 ◽

Cited By ~ 42

Author(s):

P. G. Whitehead ◽

J. Crossman ◽

B. B. Balana ◽

M. N. Futter ◽

S. Comber ◽

...

Keyword(s):

Water Quality ◽

Land Use ◽

Cost Effectiveness ◽

Land Use Change ◽

Algal Blooms ◽

Economic Benefits ◽

Point Sources ◽

Mitigation Measures ◽

Mitigation And Adaptation ◽

River Thames

The catchment of the River Thames, the principal river system in southern England, provides the main water supply for London but is highly vulnerable to changes in climate, land use and population. The river is eutrophic with significant algal blooms with phosphorus assumed to be the primary chemical indicator of ecosystem health. In the Thames Basin, phosphorus is available from point sources such as wastewater treatment plants and from diffuse sources such as agriculture. In order to predict vulnerability to future change, the integrated catchments model for phosphorus (INCA-P) has been applied to the river basin and used to assess the cost-effectiveness of a range of mitigation and adaptation strategies. It is shown that scenarios of future climate and land-use change will exacerbate the water quality problems, but a range of mitigation measures can improve the situation. A cost-effectiveness study has been undertaken to compare the economic benefits of each mitigation measure and to assess the phosphorus reductions achieved. The most effective strategy is to reduce fertilizer use by 20% together with the treatment of effluent to a high standard. Such measures will reduce the instream phosphorus concentrations to close to the EU Water Framework Directive target for the Thames.

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Assessing inundation damage and timing of adaptation: sea level rise and the complexities of land use in coastal communities

Mitigation and Adaptation Strategies for Global Change ◽

10.1007/s11027-013-9448-0 ◽

2013 ◽

Vol 19 (5) ◽

pp. 551-568 ◽

Cited By ~ 15

Author(s):

Brenda B. Lin ◽

Yong Bing Khoo ◽

Matthew Inman ◽

Chi-Hsiang Wang ◽

Sorada Tapsuwan ◽

...

Keyword(s):

Land Use ◽

Sea Level Rise ◽

Sea Level ◽

Coastal Communities

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Terrestrial Vertebrate Biodiversity Loss under Future Global Land Use Change Scenarios

Sustainability ◽

10.3390/su10082764 ◽

2018 ◽

Vol 10 (8) ◽

pp. 2764 ◽

Cited By ~ 17

Author(s):

Abhishek Chaudhary ◽

Arne Mooers

Keyword(s):

Land Use ◽

Land Use Change ◽

Low Income ◽

National Development ◽

Biodiversity Loss ◽

Mitigation Measures ◽

Climate Mitigation ◽

Meat Production ◽

Diversity Loss ◽

Global Biodiversity

Efficient forward-looking mitigation measures are needed to halt the global biodiversity decline. These require spatially explicit scenarios of expected changes in multiple indicators of biodiversity under future socio-economic and environmental conditions. Here, we link six future (2050 and 2100) global gridded maps (0.25° × 0.25° resolution) available from the land use harmonization (LUH) database, representing alternative concentration pathways (RCP) and shared socio-economic pathways (SSPs), with the countryside species–area relationship model to project the future land use change driven rates of species extinctions and phylogenetic diversity loss (in million years) for mammals, birds, and amphibians in each of the 804 terrestrial ecoregions and 176 countries and compare them with the current (1900–2015) and past (850–1900) rates of biodiversity loss. Future land-use changes are projected to commit an additional 209–818 endemic species and 1190–4402 million years of evolutionary history to extinction by 2100 depending upon the scenario. These estimates are driven by land use change only and would likely be higher once the direct effects of climate change on species are included. Among the three taxa, highest diversity loss is projected for amphibians. We found that the most aggressive climate mitigation scenario (RCP2.6 SSP-1), representing a world shifting towards a radically more sustainable path, including increasing crop yields, reduced meat production, and reduced tropical deforestation coupled with high trade, projects the lowest land use change driven global biodiversity loss. The results show that hotspots of future biodiversity loss differ depending upon the scenario, taxon, and metric considered. Future extinctions could potentially be reduced if habitat preservation is incorporated into national development plans, especially for biodiverse, low-income countries such as Indonesia, Madagascar, Tanzania, Philippines, and The Democratic Republic of Congo that are otherwise projected to suffer a high number of land use change driven extinctions under all scenarios.

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Modelling monthly runoff generation processes following land use changes: groundwater–surface runoff interactions

Hydrology and Earth System Sciences ◽

10.5194/hess-8-903-2004 ◽

2004 ◽

Vol 8 (5) ◽

pp. 903-922 ◽

Cited By ~ 13

Author(s):

M. Bari ◽

K. R. J. Smettem

Keyword(s):

Land Use ◽

Water Balance ◽

Surface Runoff ◽

Land Use Changes ◽

Annual Rainfall ◽

Rainfall Runoff ◽

Runoff Generation ◽

Mean Annual Rainfall ◽

Monthly Runoff ◽

Stream Bed

Abstract. A conceptual water balance model is presented to represent changes in monthly water balance following land use changes. Monthly rainfall–runoff, groundwater and soil moisture data from four experimental catchments in Western Australia have been analysed. Two of these catchments, "Ernies" (control, fully forested) and "Lemon" (54% cleared) are in a zone of mean annual rainfall of 725 mm, while "Salmon" (control, fully forested) and "Wights" (100% cleared) are in a zone with mean annual rainfall of 1125 mm. At the Salmon forested control catchment, streamflow comprises surface runoff, base flow and interflow components. In the Wights catchment, cleared of native forest for pasture development, all three components increased, groundwater levels rose significantly and stream zone saturated area increased from 1% to 15% of the catchment area. It took seven years after clearing for the rainfall–runoff generation process to stabilise in 1984. At the Ernies forested control catchment, the permanent groundwater system is 20 m below the stream bed and so does not contribute to streamflow. Following partial clearing of forest in the Lemon catchment, groundwater rose steadily and reached the stream bed by 1987. The streamflow increased in two phases: (i) immediately after clearing due to reduced evapotranspiration, and (ii) through an increase in the groundwater-induced stream zone saturated area after 1987. After analysing all the data available, a conceptual monthly model was created, comprising four inter-connecting stores: (i) an upper zone unsaturated store, (ii) a transient stream zone store, (ii) a lower zone unsaturated store and (iv) a saturated groundwater store. Data such as rooting depth, Leaf Area Index, soil porosity, profile thickness, depth to groundwater, stream length and surface slope were incorporated into the model as a priori defined attributes. The catchment average values for different stores were determined through matching observed and predicted monthly hydrographs. The observed and predicted monthly runoff for all catchments matched well with coefficients of determination (R2) ranging from 0.68 to 0.87. Predictions were relatively poor for: (i) the Ernies catchment (lowest rainfall, forested), and (ii) months with very high flows. Overall, the predicted mean annual streamflow was within ±8% of the observed values. Keywords: monthly streamflow, land use change, conceptual model, data-based approach, groundwater

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Rainfall-runoff modelling for assessing impacts of climate and land-use change

Hydrological Processes ◽

10.1002/hyp.5500 ◽

2004 ◽

Vol 18 (3) ◽

pp. 567-570 ◽

Cited By ~ 58

Author(s):

Axel Bronstert

Keyword(s):

Land Use ◽

Land Use Change ◽

Rainfall Runoff

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Divergencias y convergencias para asegurar la actividad agrícola en Ecuador: análisis de la parroquia Chuquiribamba (Loja) / Divergences and convergences to ensure agriculture in Ecuador: analysis of the Chuquiribamba Parrish (Loja)

Eutopía - Revista de Desarrollo Económico Territorial ◽

10.17141/eutopia.14.2018.3597 ◽

2018 ◽

Author(s):

Verónica Iñiguez-Gallardo ◽

Renato Serrano-Barbecho ◽

Fabián René Reyes Bueno

Keyword(s):

Land Use ◽

Land Use Planning ◽

Spatial Data ◽

Small Scale ◽

Agricultural Activity ◽

Spatial Variables ◽

The People ◽

Family Economy ◽

Southern Ecuador ◽

Parcel Size

La regulación de uso del suelo es un continuo debate en el proceso de planificación territorial, sobre todo en Ecuador, donde la agricultura a pequeña escala es uno de los pilares de la economía familiar para un amplio porcentaje de habitantes del sector rural. Por esta razón, identificar las variables requeridas para mantener la actividad agrícola es una necesidad y obligación. El objetivo principal de este artículo es identificar las variables espaciales que inciden sobre la probabilidad de mantener la actividad agrícola, de acuerdo con las expectativas de la gente y las características del territorio. Para ello, se comparan datos de percepción de los pobladores sobre variables tales como superficie predial, distancia a carretera, a canales de riego y a mercados, con datos espaciales de estas mismas variables. El área de estudio es la Parroquia Chuquiribamba, perteneciente al cantón Loja, al sur del Ecuador, por ser una de las principales fuentes agrícolas del sector. Los resultados sugieren convergencias entre las percepciones de la gente y las variables espaciales necesarias para asegurar la actividad agrícola, así como divergencias respecto a la normativa que regula el tamaño mínimo predial. Abstract Land-use regulation is an ongoing debate in the process of land-use planning. This is particularly true for a country such as Ecuador, where small-scale agriculture is one of the pillars of the family economy for a large percentage of inhabitants of the rural sector.  In this context, identifying the necessary variables for ensuring agricultural activities is a need and an obligation. The main objective of this article is to identify the spatial variables that affect the probability of maintaining agricultural activity, according to the expectations of the people and the characteristics of the territory. We compare data regarding the perceptions of the people of variables such as parcel size, road, irrigation and market proximity, with spatial data of the same variables. The area of study is the Chuquiribamba Parish, located in Canton Loja, in southern Ecuador. We selected it due to its agricultural importance in the Canton. The results suggest convergences between the perceptions of the people and the spatial variables necessary to safeguard agriculture, as well as divergences with the normative regulating the minimum parcel-size.

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