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Article
Publication date: 1 August 2004

D.Z. Seker, A. Tanik, M. Gurel, A. Ekdal, A. Erturk, S. Kabdasli and A. Aydingakko

This paper presents part of the results of ongoing integrated and interdisciplinary studies conducted at a vulnerable coastal lagoon system with the aim of protecting it…

Abstract

This paper presents part of the results of ongoing integrated and interdisciplinary studies conducted at a vulnerable coastal lagoon system with the aim of protecting it from further anthropogenic pollution. The target area is in southwestern Turkey, consisting of a lake that joins the Mediterranean Sea via a lagoon channel system. Land resources in the watershed are identified, including all the elements of the physical environment that influence potential land‐use, and are illustrated by the application of geographical information systems through mapping and visualization of various thematic layers of land. This study will enlighten those working on lagoon watersheds aiming at conservation of natural resources since it states the results of the studies conducted so far through various disciplines, and presents how data are utilized by the groups in an integrated manner. Based on the available data, pre‐modelling studies on hydrodynamic modelling and on water quality modelling are also referred. Identification of a watershed depends on gathering satisfactory data, which will further be used to establish sustainable development and management plans, apart from utilizing the obtained data for watershed and hydrodynamic modelling approaches and to better understand such complex systems.

Details

Management of Environmental Quality: An International Journal, vol. 15 no. 4
Type: Research Article
ISSN: 1477-7835

Keywords

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Article
Publication date: 4 January 2008

Chung‐Hung Tsai, Cheng‐Wu Chen, Wei‐Ling Chiang and Meng‐Lung Lin

Fuzzy theory provides a rigorous, flexible approach to the problem of defining and computing. Therefore, to facilitate decision making in a geographic information system…

Abstract

Purpose

Fuzzy theory provides a rigorous, flexible approach to the problem of defining and computing. Therefore, to facilitate decision making in a geographic information system (GIS), the graph layer indicator and the Takagi‐Sugeno (T‐S) fuzzy model must be integrated. This study aims to explain several versions of the T‐S fuzzy model based on fuzzy theory and fuzzy operation.

Design/methodology/approach

An inference model is constructed for GIS using the T‐S fuzzy model to formulate an integrated T‐S decision‐making (TSDMK) system.

Findings

The TSDMK system accommodates inexact, linguistic, vague and uncertain GIS data. The operator assigns most graph layer indicators by intuition.

Practical implications

Simulation results for the Hualien main station show that the proposed TSDMK system is an effective approach for GIS decision making.

Originality/value

This investigation assesses applications of fuzzy logic for decision making in a GIS based on TSDMK graphs focusing on model‐based systems.

Details

Engineering Computations, vol. 25 no. 1
Type: Research Article
ISSN: 0264-4401

Keywords

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Article
Publication date: 2 October 2007

Serafeim Polyzos and Dionissios Minetos

Non‐marketable natural coastal resources such as beaches, sand‐dune systems and cliff sides have an economic value deriving not least from the various services which they…

Abstract

Purpose

Non‐marketable natural coastal resources such as beaches, sand‐dune systems and cliff sides have an economic value deriving not least from the various services which they provide as well as the human demand for consuming some of these services. Coastal defence projects designed to protect the coast against erosion and flooding by the sea have often caused irreversible degradation to coastal natural resources. The main aim of this article is to investigate whether the joint use of cost‐benefit analysis and environmental resource valuation techniques can give any insights toward the sustainable use of the coast. Design/methodology/approach – This paper employs cost‐benefit analysis (CBA) in order to assess the justifiability of carrying out coast protection works in a particular location. This paper also uses contingent valuation methodology (CVM) to estimate the economic values of non‐marketable coastal environmental services. In particular, this paper employs willingness to pay (WTP) technique and try to elicit satisfaction values from beach users by conducting an on‐site questionnaire survey. Findings – his paper argues that there are many advantages in approaching shoreline protection project appraisal both from an environmental as well as an economics point of view. However, when conducting a cost‐benefit analysis the monetary value of environment elicited by contingent valuation techniques has very limited use in it self. It can set the financial budget within which likely coast protection options should be considered but it cannot determine which option is more sustainable. What the decision‐maker needs is to give real meaning to this value by translating it into people's specific preferences and behavioural characteristics. The next step should be setting out pragmatic project characteristics to accommodate the above preferences. Practical implications – Knowledge‐based planning and scheduling as well as informed coastal protection decisions is central to achieving sustainability in the coastal zone. Prior to managing a coastal area, the baseline information needed is the economic value of services that the coastal location in question provides. Originality/value – Generally speaking, the economic value of non‐marketable natural coastal resources such as beaches is closely associated with the way in which society perceives the environment. Both use and non‐use values that are placed upon the environment by individuals have an anthropocentric basis. In this respect, it could be argued that these values often reflect multiple coastal zone uses, conflicts of human interests, levels of environmental education, environmental awareness and environmental appreciation.

Details

Management of Environmental Quality: An International Journal, vol. 18 no. 6
Type: Research Article
ISSN: 1477-7835

Keywords

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Article
Publication date: 5 January 2010

Meng‐Lung Lin and Cheng‐Wu Chen

The purpose of this paper is to better understand landscape dynamics in arid and semi‐arid environments. Land degradation has recently become an important issue for land…

Abstract

Purpose

The purpose of this paper is to better understand landscape dynamics in arid and semi‐arid environments. Land degradation has recently become an important issue for land management in western China. The oasis ecosystem is especially sensitive to environmental disturbances, such as abnormal/extreme precipitation events, variations in the water supply from the upper watersheds, fluctuations in temperature, etc. Satellite remote sensing of terrestrial ecosystems can provide us with the temporal dynamics and spatial distributions of green cover over large areas of landscape. Seasonal green cover data are especially important in assessing landscape health (e.g. desertification, rate of urban sprawl, natural disturbances) in arid and semi‐arid regions. In this study, green cover data are derived from vegetation indices retrieved from moderate resolution imaging spectroradiometer (MODIS) sensors onboard the satellite Terra.

Design/methodology/approach

Satellite images recorded during the period from April 2000 to December 2005 are analyzed and the spatial distribution and temporal changes of the Ejin Oasis quantified.

Findings

This study shows that it is possible to derive important parameters linked to landscape sensitivity from MODIS and the derived imagery, such as normalized difference vegetation index (NDVI) time‐series data. Such a MODIS‐based time‐series monitoring system is particularly useful in arid and semi‐arid environments. The results of landscape sensitivity analysis prove the effectiveness of the method in assessing landscape sensitivity from the years 2001‐2005.

Practical implications

The novel strategy used in this investigation is based on the T‐S fuzzy model, which is in turn based on fuzzy theory and fuzzy operations.

Originality/value

Simulation results based on fuzzy models will help to improve the monitoring techniques used to evaluate land degradation and to estimate the newest tendency in landscape green cover dynamics in the Ejin Oasis.

Details

Engineering Computations, vol. 27 no. 1
Type: Research Article
ISSN: 0264-4401

Keywords

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Article
Publication date: 9 October 2009

Meng‐Lung Lin, Cheng‐Wu Chen, Qiu‐Bing Wang, Yu Cao, Jyh‐Yi Shih, Yung‐Tan Lee, Chen‐Yuan Chen and Shin Wang

The growing rate of desertification in Northwestern China and Mongolia that is occurring as a result of the conflict between economic development and natural conservation…

Abstract

Purpose

The growing rate of desertification in Northwestern China and Mongolia that is occurring as a result of the conflict between economic development and natural conservation has been demonstrated in many studies. There have, for example, been some large studies using variations in bi‐weekly normalized difference vegetation index (NDVI) satellite images as a parameter for evaluating the vegetation dynamics in these areas. The purpose of this paper is to identify multi‐temporal variation in vegetated and non‐vegetated areas in remotely sensed satellite images to assess the status of desertification in East Asia.

Design/methodology/approach

Spatial data derived from these satellite images are applied to evaluate vegetation dynamics on a regional level, to identify the areas most vulnerable to desertification.

Findings

Analytical results indicate that the desert areas in East Asia are primarily distributed over Southern Mongolia, Central and Western Inner Mongolia, and Western China (the Taklimakan Desert). These desert areas expanded from 2000 to 2002, shrunk in 2003, then expanded again from 2003 to 2005. The areas most at risk for desertification are principally distributed in Southeastern Mongolia, and Eastern Inner Mongolia.

Originality/value

Simulation results based on data for deserts distributed throughout Northwestern China and Mongolia indicate that the proposed fuzzy model‐based method would be helpful for assessing and monitoring desertification. These analytical results will help administrators refine planning processes, define the boundaries of protected areas, and facilitate decisions for prioritizing areas for desertification protection.

Details

Engineering Computations, vol. 26 no. 7
Type: Research Article
ISSN: 0264-4401

Keywords

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Article
Publication date: 30 April 2020

Perumandla Karunakar and Snehashish Chakraverty

The purpose of this paper is to find the solution of classical nonlinear shallow-water wave (SWW) equations in particular to the tsunami wave propagation in crisp and…

Abstract

Purpose

The purpose of this paper is to find the solution of classical nonlinear shallow-water wave (SWW) equations in particular to the tsunami wave propagation in crisp and interval environment.

Design/methodology/approach

Homotopy perturbation method (HPM) has been used for handling crisp and uncertain differential equations governing SWW equations.

Findings

The wave height and depth-averaged velocity of a tsunami wave in crisp and interval cases have been obtained.

Originality/value

Present results by HPM are compared with the existing solution (in crisp case), and they are found to be in good agreement. Also, the residual error of the solutions is found for the convergence conformation and reliability of the present results.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 31 no. 1
Type: Research Article
ISSN: 0961-5539

Keywords

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Article
Publication date: 27 February 2009

Maja Radetic, Darinka Radojevic, Vesna Ilic, Darka Mihailovic and Petar Jovancic

The purpose of this paper is to investigate the possible application of recycled wool‐based nonwoven material (RWNM) for removal of different dyes that are used in textile…

Abstract

Purpose

The purpose of this paper is to investigate the possible application of recycled wool‐based nonwoven material (RWNM) for removal of different dyes that are used in textile dye houses.

Design/methodology/approach

The sorption kinetics, the influence of initial dye concentration, pH and temperature are analyzed. Basic, reactive, direct and metal complex dyes are studied.

Findings

The sorption properties are highly influenced by the type of the dye owing to differences in their chemical structure and thus, the mechanism of binding to wool. Modification of material with chitosan and hydrogen peroxide improves the sorption capacities and sorption rates but no general trend can be established. Consequently, the sorption behaviour is analyzed separately for each type of the dye.

Originality/value

The results indicate that RWNM can be used as an efficient, low‐cost sorbent for decolorisation of effluents.

Details

International Journal of Clothing Science and Technology, vol. 21 no. 2/3
Type: Research Article
ISSN: 0955-6222

Keywords

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