ABSTRACT Coastal floodplains are complex regions that form the interface between human, physical ... more ABSTRACT Coastal floodplains are complex regions that form the interface between human, physical and natural systems. This paper describes the development, application and evaluation of a conceptual foundation for quantitative integrated floodplain risk assessments using the recently-developed SPR systems model. The SPR systems model is a conceptual model that combines the well-established Source–Pathway–Receptor (SPR) approach with the concept of system diagrams. In comparison to the conventional approach, the systems model provides spatially explicit quasi-2D descriptions of the floodplain in terms of constituent elements and possible element linkages. The quasi-2D SPR, as it will henceforth be referred to in this paper, is not the final product of this work, but is an important intermediate stage which has been pursued as part of a wider European flood risk project THESEUS (www.theseusproject.eu). Further research is currently on-going to provide full quantification of the quasi-2D SPR, and to add further refinements such that hydraulic assessments could follow on easily and rapidly from the results of these appraisals. The first part of the paper synthesises current conceptual treatment of coastal floodplains and identifies areas for improvement in describing coastal floodplains as complex systems. The synthesis demonstrates that the conceptual foundation of a ‘typical’ flood risk study often achieves a less comprehensive and integrated description of the floodplain than the quantitative models which it informs. From this synthesis, the quasi-2D SPR is identified as a more robust and informative conceptual foundation for an integrated risk assessment. The quasi-2D SPR has been applied to seven European coastal floodplains as part of the THESEUS project. The second part of the paper discusses in detail the application of the quasi-2D SPR to three contrasting floodplain systems — an estuary, a coastal peninsula and a mixed open coast/estuary site. The quasi-2D SPR provides a consistent approach for achieving comprehensive floodplain descriptions that are individual to each coastal floodplain. These are obtained through a robust, participatory model-building exercise, that facilitates developing a shared understanding of the system. The constructed model is a powerful tool for structuring and integrating existing knowledge across multiple disciplines. Applications of the quasi-2D SPR provide key insights into the characteristics of complex coastal floodplains — insights that will inform the quantification process. Finally, the paper briefly describes the on-going quantitative extension to the quasi-2D SPR.
COASTAL HABITATS WITHIN FLOOD RISK ASSESSMENTS: ROLE OF THE 2D SPR APPROACH
ABSTRACT Coastal habitats are highly threatened ecosystems that are sensitive to complex sets of ... more ABSTRACT Coastal habitats are highly threatened ecosystems that are sensitive to complex sets of natural and human drivers. Europe’s coastal habitats are protected from damage due to human activity by the EU Habitats Directive, and are required to be mapped within flood risk assessments by the EU Floods Directive. Ecological vulnerability and risk assessments are a common way of assessing the impacts on these habitats due to human and natural drivers. Coastal flood risk assessments therefore often include assessments of the vulnerability of coastal habitats. Flood risk assessments also evaluate, where relevant, the mitigation services provided by coastal habitats. The two aspects of coastal habitats – their flood mitigation service and their ecological vulnerability are strongly correlated; however these are usually treated separately within flood risk assessments. One of the goals of the EU THESEUS project is the integrated consideration of coastal habitats within flood risk assessments. This paper investigates the integration within flood risk assessments of the two aspects of coastal habitats using the 2D SPR conceptual model. The construction of the model is first illustrated by application to a generic study site. The model is then applied to a case-study where data on habitat elevations and vulnerabilities to flood events have been collected. The model provides a unique and robust means of combining information on ecological vulnerability indices for different habitat associations with information on their distribution and spatial relationships within the coastal floodplain. Used in conjunction with information on habitat vulnerability indices, the conceptual model serves as a powerful tool for integrated and structured consideration of coastal habitats within flood risk assessments.
Temperature responsive fluid flow control device
Soil water balance model of a grass-covered clay slope in England
Proceedings of the International Symposium on Dams in the Societies of the 21st Century, 22nd International Congress on Large Dams (ICOLD), Barcelona, Spain, 18 June 2006, 2006
Software evaluation criteria - the users
Predicted effects of climate change and sea level rise on water table levels and dune slack habitats
New nuclear build: adaptation options over the full life-cycle
1300 years of Development of Irrigation at the Otrar Oasis, Kazakhstan
The karez of the Sauran region of Central Asia
Water Science & Technology: Water Supply, 2010
ABSTRACT
Coastal Habitats Within Flood Risk Assessments: Role of the 2D SPR Approach
ABSTRACT Coastal habitats are highly threatened ecosystems that are sensitive to complex sets of ... more ABSTRACT Coastal habitats are highly threatened ecosystems that are sensitive to complex sets of natural and human drivers. Europe’s coastal habitats are protected from damage due to human activity by the EU Habitats Directive, and are required to be mapped within flood risk assessments by the EU Floods Directive. Ecological vulnerability and risk assessments are a common way of assessing the impacts on these habitats due to human and natural drivers. Coastal flood risk assessments therefore often include assessments of the vulnerability of coastal habitats. Flood risk assessments also evaluate, where relevant, the mitigation services provided by coastal habitats. The two aspects of coastal habitats – their flood mitigation service and their ecological vulnerability are strongly correlated; however these are usually treated separately within flood risk assessments. One of the goals of the EU THESEUS project is the integrated consideration of coastal habitats within flood risk assessments. This paper investigates the integration within flood risk assessments of the two aspects of coastal habitats using the 2D SPR conceptual model. The construction of the model is first illustrated by application to a generic study site. The model is then applied to a case-study where data on habitat elevations and vulnerabilities to flood events have been collected. The model provides a unique and robust means of combining information on ecological vulnerability indices for different habitat associations with information on their distribution and spatial relationships within the coastal floodplain. Used in conjunction with information on habitat vulnerability indices, the conceptual model serves as a powerful tool for integrated and structured consideration of coastal habitats within flood risk assessments.
Dune slack habitats are highly dependent on the availability of water to support flora and fauna.... more Dune slack habitats are highly dependent on the availability of water to support flora and fauna. Typically this is provided by shallow groundwater. This paper describes the seasonal and long term variation in groundwater levels in part of the Sefton coastline between 1972 and 2007. The effects of climate change, vegetation management and coastline realignment on groundwater levels are modelled. The observed annual water table levels rise and fall with an amplitude of 1.5 m, but longer term variations and trends are apparent. A stochastic water balance model was used to describe the changes in water table levels in slack floors in the open dunes and also in areas afforested with pine trees. It was found that the pine trees evaporated 214 mm/year more than open dunes vegetation, resulting in the water table being 0.5-1.0 m lower under the trees than under the open dunes. The effects of climate change on the ground water was simulated using predictions of future climate conditions based on the UKCIP02 medium high emissions scenario. The increase in temperature and change in rainfall patterns will result in a decrease in mean ground water levels by 1.0-1.5 mm in the next 90 years. Typical patterns consist of sequences of 5-10 years of low water table levels interspersed by infrequent sequences consisting of 2-5 years of relatively high or "normal" levels. These results indicate that that flora and fauna that cannot survive a 5-10 year period of water table levels >2.5 m below ground level are unlikely to survive or persist in many slack areas and a change in the ecology of these slack may become inevitable. Other effects of climate change include sea level rise which will result in a gradual rise in water table levels. Coastal erosion will increase the water table gradient to the sea and result in a slight lowering of the ground water levels. Conversely coastal accretion will reverse this process. The spatial distribution of coastal erosion and accretion along the Sefton coastline and its likely impacts on groundwater levels are discussed. The modelling work described in this paper has identified the factors which have the largest effect on groundwater levels in temperate coastal dune systems.
The FAO AquaCrop model has been widely applied throughout the world to simulate crop responses to... more The FAO AquaCrop model has been widely applied throughout the world to simulate crop responses to deficit water applications. However, its application to saline conditions is not yet reported, though saline soils are common in coastal areas. In this study, we parameterized and tested AquaCrop to simulate rice yield under different salinity regimes. The data and information required in the model were collected through a field experiment at the Bangladesh Agricultural Research Institute, Gazipur. The experiment was conducted with the BRRI Dhan28, a popular boro rice variety in Bangladesh, with five levels of saline water irrigation, three replicates for each level. In addition, field monitoring was carried out at Satkhira in the southwest coastal region of Bangladesh to collect data and information based on farmers' practices and to further validate the model. The results indicated that the AquaCrop model with most of its default parameters could replicate the variation of rice yield with the variation of salinity reasonably well. The root mean square error and mean absolute error of the model yield were only 0.12 t per ha and 0.03 t per ha, respectively. The crop response versus soil salinity stress curve was found to be convex in shape with a lower threshold of 2 dS m(-1), an upper threshold of 10 dS m(-1) and a shape factor of 2.4. As the crop production system in the coastal belt of Bangladesh has become vulnerable to climate induced sea-level rise and the consequent increase in water and soil salinity, the AquaCrop would be a useful tool in assessing the potential impact of these future changes as well as other climatic parameters on rice yield in the coastal region.
r To investigate loss of skeletal muscle mass in intrauterine growth-restricted (IUGR) fetuses ne... more r To investigate loss of skeletal muscle mass in intrauterine growth-restricted (IUGR) fetuses near term, which may result from myoblast dysfunction, we examined semitendinosus myofibre and myoblast morphology in placental insufficiency-induced IUGR sheep fetuses; we also isolated and cultured IUGR fetal myoblasts to determine whether reduced rates of proliferation were due to intrinsic cellular defects or extrinsic factors associated with serum. r Using tests for myogenin and pax7 to identify differentiated and undifferentiated fetal myoblasts, respectively, we found that myofibre area and percentage of myogenin-positive nuclei were less in IUGR fetal semitendinosus muscles than in controls, but myofibre density and percentage of pax7-positive nuclei were not different.
Design of Hydraulically Efficient Power-Law Channels with Freeboard
Journal of Irrigation and Drainage Engineering, 2005
Design of Hydraulically Efficient Power-Law Channels with Freeboard. [Journal of Irrigation and D... more Design of Hydraulically Efficient Power-Law Channels with Freeboard. [Journal of Irrigation and Drainage Engineering 131, 560 (2005)]. Arif A. Anwar, Derek Clarke. Abstract. A power-law channel is a generalized form of the parabolic channel. ...
Evaluation of a Genetic Algorithm for the Irrigation Scheduling Problem
Journal of Irrigation and Drainage Engineering, 2008
A typical irrigation scheduling problem is one of preparing a schedule to service a group of outl... more A typical irrigation scheduling problem is one of preparing a schedule to service a group of outlets which may be serviced simultaneously. This problem has an analogy with the classical earliness/tardiness problem in operations research. In previously published work an ...
Irrigation Scheduling Using Mixed-Integer Linear Programming
Journal of Irrigation and Drainage Engineering, 2001
Irrigation Scheduling Using Mixed-Integer Linear Programming. [Journal of Irrigation and Drainage... more Irrigation Scheduling Using Mixed-Integer Linear Programming. [Journal of Irrigation and Drainage Engineering 127, 63 (2001)]. Arif A. Anwar, Derek Clarke. Abstract. A mixed-integer program is presented for scheduling canal ...
To date, arranged demand irrigation and on-demand irrigation were considered as two distinct type... more To date, arranged demand irrigation and on-demand irrigation were considered as two distinct types of systems. This paper presents the hypothesis that arranged demand is a continuous function with on-demand as one extreme and fully arranged demand as the other. This paper introduces the index of relative timeliness to capture this semantic. This index assumes a value of 1 for an ondemand system and 0 for a fully arranged demand system. This paper then demonstrates that how this index can be incorporated in mathematical modelling. An earlier integer programme is modified to include the concept of relative timeliness. As a case study an existing tertiary unit is simulated using this tool to investigate whether, given its current capacity, the tertiary unit can be operated on an arranged demand basis, and if so what level of service can be expected. The model also indicates what capacity is required if the tertiary unit were to be operated on an on-demand basis. The capacity requirements as predicted by the model developed in this work relate well to earlier empirical/ experience guidelines. The model developed is useful for investigating and simulating existing tertiary units, but in its current form cannot be used for general design guidelines for new designs. Some recommendations for further developments are made. #
Long term archives of reported flooding in the UK from 1884-2012 are used to build an indicator d... more Long term archives of reported flooding in the UK from 1884-2012 are used to build an indicator dataset of significant flooding at a national scale in England. The report describes the occurrence of significant flood events on a national scale based on the monthly UK Met Office weather reports and auxiliary sources. Unlike previous studies, which use flow gauging records, these data describe the occurrence of a flood event that affected people and property i.e. they are not flow station specific. The descriptions of reported flood events are classified in order of magnitude, extent and impact. Notable and significant reported flood events are analysed to determine long term temporal trends, changes in seasonality (summer/winter) and to detect any changes in spatial distribution and scale over the last 120 years. The 19th century reports are less frequent, suggesting that flooding became much more common over the 20th century; however this may be due to an increase in rates of exposu...
Coastal Bangladesh experiences significant poverty and hazards today and is highly vulnerable to ... more Coastal Bangladesh experiences significant poverty and hazards today and is highly vulnerable to climate and environmental change over the coming decades. Coastal stakeholders are demanding information to assist in the decision making processes, including simulation models to explore how different interventions, under different plausible future socio-economic and environmental scenarios, could alleviate environmental risks and promote development. Many existing simulation models neglect the complex interdependencies between the socio-economic and environmental system of coastal Bangladesh. Here an integrated approach has been proposed to develop a simulation model to support agriculture and poverty-based analysis and decision-making in coastal Bangladesh. In particular, we show how a simulation model of farmer's livelihoods at the household level can be achieved. An extended version of the FAO's CROPWAT agriculture model has been integrated with a downscaled regional demography model to simulate net agriculture profit. This is used together with a household income-expenses balance and a loans logical tree to simulate the evolution of food security indicators and poverty levels. Modelling identifies salinity and temperature stress as limiting factors to crop productivity and fertilisation due to atmospheric carbon dioxide concentrations as a reinforcing factor. The crop simulation results compare well with expected outcomes but also reveal some unexpected behaviours. For example, under current model assumptions, temperature is more important than salinity for crop production.
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