Environmental Degradation (environmental + degradation)

Distribution by Scientific Domains
Distribution within Life Sciences


Selected Abstracts


Modeling of Environmental Degradation in Fatigue-Life Prediction of Near-, Titanium Alloy IMI 834 under Complex High-Temperature Loading Conditions,

ADVANCED ENGINEERING MATERIALS, Issue 6 2003
R.G. Teteruk
The crack propagation model successfully applies to life-prediction of near-,-titanium alloy IMI 834 under complex high-temperature fatigue-loading conditions. The predictive capabilities of the model can be attributed to the close correlation of the model with the relevant damage mechanisms (among them environmental degradation under varying conditions) and micro-structural processes. The Figure shows an SEM image of a typical crack-initiation site for a test run at 400,°C. [source]


Not How, But Why ? Beyond proximate cause for environmental degradation

CONSERVATION, Issue 1 2005
David Rains Wallace
[source]


Conservation Challenges for the Austral and Neotropical America Section

CONSERVATION BIOLOGY, Issue 4 2009
GERARDO CEBALLOS
América Austral y Neotropical; América Latina; desarrollo de capacidades Abstract:,The Austral and Neotropical America (ANA) section of the Society for Conservation Biology includes a vast territory with some of the largest relatively pristine ecosystems in the world. With more than 573 million people, the economic growth of the region still depends strongly on natural resource exploitation and still has high rates of environmental degradation and biodiversity loss. A survey among the ANA section membership, with more than 700 members, including most of the section's prominent ecologists and conservationists, indicates that lack of capacity building for conservation, corruption, and threats such as deforestation and illegal trade of species, are among the most urgent problems that need to be addressed to improve conservation in the region. There are, however, strong universities and ecology groups taking the lead in environmental research and conservation, a most important issue to enhance the ability of the region to solve conservation and development conflicts. Resumen:,La sección América Austral y Neotropical (AAN) de la Sociedad para la Biología de la Conservación incluye un vasto territorio con unos de los ecosistemas relativamente prístinos más extensos del mundo. Con más de 573 millones de habitantes, el crecimiento económico de la región aun depende fuertemente de la explotación de recursos naturales y aún tiene altas tasas de degradación ambiental y pérdida de biodiversidad. Un sondeo de la membresía de la sección AAN, con más de 700 miembros, incluyendo la mayoría de los ecólogos y conservacionistas más prominentes de la sección, indica que la carencia de desarrollo de capacidades para la conservación, la corrupción y amenazas como la deforestación y el comercio ilegal de especies, son algunos de los problemas que requieren ser atendidos más urgentemente para mejorar la conservación en la región. Sin embargo, hay universidades y grupos ecológicos que están tomando el liderazgo en investigación ambiental y conservación, un tema importante para mejorar la habilidad de la región para resolver conflictos de conservación y desarrollo. [source]


Motivations for the Restoration of Ecosystems

CONSERVATION BIOLOGY, Issue 2 2006
ANDRE F. CLEWELL
cambio climático; capital natural; restauración ecológica Abstract:,The reasons ecosystems should be restored are numerous, disparate, generally understated, and commonly underappreciated. We offer a typology in which these reasons,or motivations,are ordered among five rationales: technocratic, biotic, heuristic, idealistic, and pragmatic. The technocratic rationale encompasses restoration that is conducted by government agencies or other large organizations to satisfy specific institutional missions and mandates. The biotic rationale for restoration is to recover lost aspects of local biodiversity. The heuristic rationale attempts to elicit or demonstrate ecological principles and biotic expressions. The idealistic rationale consists of personal and cultural expressions of concern or atonement for environmental degradation, reengagement with nature, and/or spiritual fulfillment. The pragmatic rationale seeks to recover or repair ecosystems for their capacity to provide a broad array of natural services and products upon which human economies depend and to counteract extremes in climate caused by ecosystem loss. We propose that technocratic restoration, as currently conceived and practiced, is too narrow in scope and should be broadened to include the pragmatic rationale whose overarching importance is just beginning to be recognized. We suggest that technocratic restoration is too authoritarian, that idealistic restoration is overly restricted by lack of administrative strengths, and that a melding of the two approaches would benefit both. Three recent examples are given of restoration that blends the technocratic, idealistic, and pragmatic rationales and demonstrates the potential for a more unified approach. The biotic and heuristic rationales can be satisfied within the contexts of the other rationales. Resumen:,Las razones por la que los ecosistemas deben ser restaurados son numerosas, dispares, generalmente poco sustentadas, y comúnmente poco apreciadas. Ofrecemos una tipología en la que estas razones,o motivaciones,son ordenadas entre cinco razonamientos: tecnocrático, biótico, heurístico, idealista y pragmático. El razonamiento tecnocrático se refiere a la restauración que es llevada a cabo por agencias gubernamentales u otras grandes organizaciones para satisfacer misiones y mandatos institucionales específicos. El razonamiento biótico de la restauración es la recuperación de aspectos perdidos de la biodiversidad local. El razonamiento heurístico intenta extraer o demostrar principios ecológicos y expresiones bióticas. El razonamiento idealista consiste de expresiones personales y culturales de la preocupación o reparación de la degradación ambiental, reencuentro con la naturaleza y/o cumplimiento espiritual. El razonamiento pragmático busca recuperar o reparar ecosistemas por su capacidad de proporcionar una amplia gama de servicios y productos naturales de la que dependen las economías humanas y para contrarrestar extremos en el clima causados por la pérdida de ecosistemas. Proponemos que la restauración tecnocrática, como se concibe y practica actualmente, es muy corta en su alcance y debiera ampliarse para incluir al razonamiento pragmático, cuya importancia apenas comienza a ser reconocida. Sugerimos que la restauración tecnocrática es demasiado autoritaria, que la restauración idealista esta muy restringida por la falta de fortalezas administrativas, y que una mezcla de los dos enfoques podría beneficiar a ambas. Proporcionamos tres ejemplos recientes de restauración que combinan los razonamientos tecnocrático, idealista y pragmático y demuestran el potencial para un enfoque más unificado. Los razonamientos biótico y heurístico pueden ser satisfechos en el contexto de los otros razonamientos. [source]


Effects of Economic Prosperity on Numbers of Threatened Species

CONSERVATION BIOLOGY, Issue 4 2001
Robin Naidoo
We corrected for factors that might otherwise confound such a relationship. Our study was motivated by the continuing debate over the relationship between environmental degradation and per-capita income. Proponents of the environmental Kuznets-curve hypothesis argue that although environmental degradation may increase initially, increases in per-capita income will eventually result in greater environmental quality. Theoretical objections and the lack of widespread empirical evidence recently have thrown doubt on the existence of such a pattern. Treating threat to biodiversity as one potential indicator of environmental degradation, we divided threatened species into seven taxonomic groups ( plants, mammals, birds, amphibians, reptiles, fishes, and invertebrates) and analyzed each group separately. Count-data regression analysis indicated that the number of threatened species was related to per-capita gross national product in five of seven taxonomic groups. Birds were the only taxonomic group in which numbers of threatened species decreased throughout the range of developed countries' per-capita gross national product. Plants, amphibians, reptiles, and invertebrates showed increasing numbers of threatened species throughout this same range. If these relationships hold, increasing numbers of species from several taxonomic groups are likely to be threatened with extinction as countries increase in prosperity. A key challenge is to understand the interactions among consumer preferences, biology, and institutions that lead to the relationship observed for birds and to see whether this knowledge can be applied to conservation of other taxa. Resumen: Utilizamos datos de más de 100 países para investigar la relación entre números de especies amenazadas y el producto interno bruto per cápita. Hicimos ajustes para factores que pudieran confundir tal relación. Nuestro estudio fue motivado por el continuo debate sobre la relación entre la degradación ambiental y el ingreso per cápita. Proponentes de la hipótesis de la curva ambiental de Kuznets argumentan que, aunque la degradación ambiental puede aumentar inicialmente, el incremento en el ingreso per cápita eventualmente resultará en una mejor calidad ambiental. Recientemente, objeciones teóricas y la carencia de evidencia empírica generalizada hacen dudar de la existencia de ese patrón. Tratando la amenaza a la biodiversidad como un potencial indicador de la degradación ambiental, dividimos a las especies amenazadas en siete grupos taxonómicos (plantas, mamíferos, aves, anfibios, reptiles, peces e invertebrados) y analizamos cada uno por separado. El análisis de regresión de los datos de conteo indicó que el número de especies amenazadas se relacionó con el producto interno bruto per cápita en 5 de los 7 grupos taxonómicos. Las aves fueron el único grupo en el que el número de especies amenazadas decreció a lo largo del rango del producto interno bruto per cápita de los países desarrollados. Las plantas, anfibios, reptiles e invertebrados mostraron un incremento en el número de especies amenazadas en este mismo rango. Si estas relaciones persisten, es posible que aumente el número de especies, de varios grupos taxonómicos, amenazadas de extinción a medida que los países incrementen su prosperidad. Constituye un reto clave entender las interacciones entre la preferencia de los consumidores y los factores biológicos e institucionales que conducen a la relación observada en las aves, y ver si este conocimiento puede aplicarse en la conservación de otros taxones. [source]


The role of organizational size in the adoption of green supply chain management practices in China

CORPORATE SOCIAL RESPONSIBILITY AND ENVIRONMENTAL MANAGEMENT, Issue 6 2008
Qinghua Zhu
Abstract Economic globalization, increasing resource scarcity and environmental degradation have caused green supply chain management (GSCM) to become an important competitive approach for organizations involved in international trade. Using survey data collected from over 200 China-based organizations, we compare the implementation levels of five GSCM practices among small-, medium- and large-sized organizations in China. We find that medium- and large-sized organizations are more advanced than their smaller-sized counterparts on most aspects, but not necessarily all, of these GSCM practices. Future research includes possible studies on GSCM practices and promotion, especially targeting small manufacturing organizations. In addition, the influence of globalization and foreign direct investment, especially after China's entry into the WTO, could be more carefully examined. Copyright © 2008 John Wiley & Sons, Ltd and ERP Environment. [source]


Prospects and Challenges for Growth and Poverty Reduction in Asia

DEVELOPMENT POLICY REVIEW, Issue 2006
John Humphrey
The extent of poverty reduction in Asia by 2015 will depend upon two linked issues: sustaining the current rates of economic growth and avoiding increases in income inequality. Rapid growth over the past 15 years has itself created three challenges for its continuation: inadequate infrastructure; energy shortages and insecurity; and depletion of natural resources and environmental degradation. The ways in which these problems are addressed will have impacts not only on growth but also on inequality, requiring policy interventions at multiple levels, having implications for governance at multiple levels, and involving the development of new partnerships within the region and beyond. [source]


The Machakos Case Study: Solid Outcomes, Unhelpful Hyperbole

DEVELOPMENT POLICY REVIEW, Issue 1 2006
Jules Siedenburg
This article revisits the well-known study of Machakos District, Kenya reported in the book More People, Less Erosion by Tiffen et al., which found dramatic, compelling evidence of successful endogenous adaptation to changing circumstances by rural Africans. The article seeks to elucidate discrepancies between the Machakos findings and other findings in the interest of both scientific accuracy and policy relevance. It is suggested that the Machakos study comprises hopeful data, on the one hand, and problematic calculations and assertions, on the other. After exploring problems with the study, the article suggests an alternative interpretation of the data that is arguably more pertinent to contemporary concerns with rural poverty and environmental degradation as well as more widely applicable in sub-Saharan Africa. [source]


Implications of Liebig's law of the minimum for the use of ecological indicators based on abundance

ECOGRAPHY, Issue 2 2005
J. G. Hiddink
Many ecological responses to environmental variables or anthropogenic agents are difficult and expensive to measure. Therefore it is attractive to describe such responses in terms of indicators that are easier to measure. In ecosystem management, indicators can be used to monitor spatial and temporal changes in an environmental feature. The aim of this paper is to show that it is important to take Liebig's law of the minimum into consideration to understand when it is appropriate or inappropriate to use ecological indicators based on abundance. When developing indicators that relate the abundance of an organism to an environmental factor, it is likely that this relationship will be polygonal rather than a simple linear relationship. The upper boundary of the distribution describes how abundance is limited by this factor, while the variation below the upper boundary is explained by situations when factors other than the factor of interest limit abundance. The variation below the upper boundary of the distribution means that the use of indicators to examine spatial patterns in the response of abundance to an environmental factor can be problematic. Thus, while abundance-based indicators can identify sites that are in a good condition, they are less useful to detect those affected by environmental degradation. In contrast, abundance-based ecological indicators may enable temporal monitoring of the impact of environmental factors, as it is expected that limiting factors are less variable in time than in space. In conclusion, when multiple factors are limiting, a significant correlation between an indicator and a variable is not enough to validate the status of a factor as an indicator. [source]


Edible insects: Traditional knowledge or western phobia?

ENTOMOLOGICAL RESEARCH, Issue 5 2009
Alan L. YEN
Abstract With an increasing human population and environmental degradation, the world faces a major problem in providing adequate animal based proteins. Many traditional societies have used or still use insects as a protein source, while westernized societies are reluctant to use insects, despite being the major consumers of animal proteins. We now need to consider insects as a source of food for humans in a manner that acknowledges both the role of entomophagy in indigenous societies and the need for westernized societies to reduce the size of their environmental footprint with regard to food production. The situation on continents such as Africa, Asia, and Central and South America has some parallels to Australia in that there are two forces in operation: the sustainable traditional use of edible insects and the "westernization" of these societies leading to a movement away from entomophagy. However, the potential to reach a compromise is greater in these continents because entomophagy is already accepted. The major challenges will be establishing sustainable production systems that include food safety and security as well as environmental protection. Whether this will happen or not will depend upon: (i) a major change in attitude in westernized societies towards entomophagy; (ii) pressure to conserve remaining habitats in a sustainable manner; (iii) economic impetus to develop food production systems that include insects; and (iv) an acknowledgement that achieving adequate nutrition on a global basis will involve different diets in much of the developed world. [source]


Understanding the costs of an environmentally ,friendly' common agricultural policy for the European Union1,

ENVIRONMENTAL POLICY AND GOVERNANCE, Issue 1 2001
Pamela M. Barnes
Part of the bedrock of the European Union's (EU's) Environmental Policy is the principle that those who pollute the environment should pay for the cost of remedying the damage they cause (the polluter pays principle) (Article 174 para. 2 TEC ex Article 130r TEC). In addition environmental objectives must be integrated into all the sectoral policies of the European Union (Article 6 TEC ex Article 3c TEC). The Common Agricultural Policy's (CAP's) role at the centre of the EU's sectoral policies would appear to make it an ideal focus for implementing Article 6 of the Treaty establishing the European Community (TEC). If integration of environmental protection can be achieved in this central area of the EU's activities then a major source of environmental degradation could be overcome. However, if these requirements are applied to European agriculture the sector will face a budgetary and financial crisis of even greater magnitude than at the present time. Recent reforms of the CAP have been designed with the objective of achieving an agricultural sector that is moving towards sustainability. As this article argues the political, social and economic significance of the agriculture sector is such that national governments of the EU have repeatedly shied away from adopting the measures, which could significantly reduce the pollution from the sector. The proposals for reform made by the Agricultural Commissioner, Franz Fischler, were amended by the meeting of the European Council that took place in Berlin on 24/25 March 1999. These amendments substantially weakened the ambitions of the strategy for development of the EU, the ,Agenda 2000' adopted in 1997, for a number of reasons (CEC, 1997). This article examines the reasons for the disappointments with the amended reforms and speculates on the possible future path that may be taken to improve matters. Copyright © 2001 John Wiley & Sons, Ltd and ERP Environment. [source]


Genetic diversity of Clethrionomys glareolus populations from highly contaminated sites in the Chornobyl region, Ukraine

ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 8 2000
Cole W. Matson
Abstract At radioactive sites, at least two mechanisms may affect the genetic diversity of populations of a given species. Increased mutation rates due to radiation exposure may increase the amount of genetic diversity in a population. Alternatively, population bottlenecks exacerbated by environmental degradation may lead to a reduction of diversity. The relationship between these two contradictory forces is complex. To explore this relationship, long-term monitoring of a genetic marker within a population is needed. To provide baseline data on the population genetics of the bank vole (Clethrionomys glareolus) living in the most contaminated regions at Chornobyl, Ukraine, we have sequenced 291 base pairs of the mitochondrial DNA control region. Bank voles were chosen as a model system because they have the highest levels of internal dose of cesium-134, cesium-137, and strontium-90 within the Chornobyl exclusion zone. We sampled three geographic sites, which were Oranoe, a reference site with virtually no radioactive contamination (<2 Ci/km2), and two highly contaminated sites, Glyboke Lake and the Red Forest (both 1,000 Ci/km2). Genetic diversity in the population from Red Forest (0.722 ± 0.024) was significantly greater than at the Oranoe reference site (0.615 ± 0.039), while genetic diversity at Glyboke Lake (0.677 ± 0.068) was intermediate. It is concluded that long-term studies of historical and demographic characteristics for experimental and reference populations are required in order to employ population genetics to understand the biological impact of environmental contaminants on the genetics of natural populations. [source]


Loss of phosphorus from soil in semi-arid northern Tanzania as a result of cropping: evidence from sequential extraction and 31P-NMR spectroscopy

EUROPEAN JOURNAL OF SOIL SCIENCE, Issue 4 2000
D. Solomon
Summary In semi-arid northern Tanzania, the native woodland is being rapidly cleared and replaced by low input agriculture. This has resulted in pronounced environmental degradation, and in particular loss of phosphorus (P) from the soil. We have used sequential extraction and 31P-NMR to investigate the effects of land use changes, i.e. native woodland, degraded woodland, cultivation for 3 and 15 years and homestead fields where manure was applied, on the amount and structural composition of P in this soil. Clearing and continuous cultivation reduced both organic and inorganic P in the soil. The difference in the amount of organic P from the bulk soil of the fields cultivated for 3 and 15 years was not statistically significant (P <,0.05), suggesting that most of the depletion in organic P occurred during the first 3 years of cultivation. By contrast, in the homesteads, there was much organic and inorganic P in the soil. The 31P-NMR revealed that cultivation resulted in a 53% depletion of orthophosphate diester P, whereas only a 30% and 39% reduction of orthophosphate monoester P was found in the bulk soil after 3 and 15 years of cultivation, respectively. These results concur with the suggestion that diester P constitutes more easily mineralizable forms of organic P in soil than does monoester P. Our 31P-NMR also showed that 70% of the inorganic orthophosphate P was depleted from the coarse and fine sand separates as a result of cultivation. The influence of clearing and subsequent cropping on the amount and forms of P was more pronounced in the coarse and fine sand than in the silt and clay, stressing the importance of particle size and chemical properties such as organic matter and oxides in the availability of P in this soil. Our results show that the current low input agricultural practice is not sustainable, and that practices must be developed to combat the ongoing degradation of the soil. A combined use of available organic materials such as animal manure with the judicious use of inorganic fertilizers can replenish the soil's fertility. [source]


Seed supply for broadscale restoration: maximizing evolutionary potential

EVOLUTIONARY APPLICATIONS (ELECTRONIC), Issue 4 2008
Linda M. Broadhurst
Abstract Restoring degraded land to combat environmental degradation requires the collection of vast quantities of germplasm (seed). Sourcing this material raises questions related to provenance selection, seed quality and harvest sustainability. Restoration guidelines strongly recommend using local sources to maximize local adaptation and prevent outbreeding depression, but in highly modified landscapes this restricts collection to small remnants where limited, poor quality seed is available, and where harvesting impacts may be high. We review three principles guiding the sourcing of restoration germplasm: (i) the appropriateness of using ,local' seed, (ii) sample sizes and population characteristics required to capture sufficient genetic diversity to establish self-sustaining populations and (iii) the impact of over-harvesting source populations. We review these topics by examining current collection guidelines and the evidence supporting these, then we consider if the guidelines can be improved and the consequences of not doing so. We find that the emphasis on local seed sourcing will, in many cases, lead to poor restoration outcomes, particularly at broad geographic scales. We suggest that seed sourcing should concentrate less on local collection and more on capturing high quality and genetically diverse seed to maximize the adaptive potential of restoration efforts to current and future environmental change. [source]


Modeling of Environmental Degradation in Fatigue-Life Prediction of Near-, Titanium Alloy IMI 834 under Complex High-Temperature Loading Conditions,

ADVANCED ENGINEERING MATERIALS, Issue 6 2003
R.G. Teteruk
The crack propagation model successfully applies to life-prediction of near-,-titanium alloy IMI 834 under complex high-temperature fatigue-loading conditions. The predictive capabilities of the model can be attributed to the close correlation of the model with the relevant damage mechanisms (among them environmental degradation under varying conditions) and micro-structural processes. The Figure shows an SEM image of a typical crack-initiation site for a test run at 400,°C. [source]


Reconciling traditional inland fisheries management and sustainability in industrialized countries, with emphasis on Europe

FISH AND FISHERIES, Issue 4 2002
Robert Arlinghaus
Abstract In northern industrialized countries, the inland fisheries sector has long been dominated by recreational fisheries, which normally exploit fish for leisure or subsistence and provide many (poorly investigated) benefits to society. Various factors constrain the development and existence of inland fisheries, such as local user conflicts, low social priority and inadequate research and funding. In many cases, however, degradation of the environment and loss of aquatic habitat are the predominant concerns for the sustainability of inland fisheries. The need for concerted effort to prevent and reduce environmental degradation, as well as conservation of freshwater fish and fisheries as renewable common pool resources or entities in their own right is the greatest challenge facing sustainable development of inland waters. In inland fisheries management, the declining quality of the aquatic environment coupled with long-term inadequate and often inappropriate fisheries management has led to an emphasis on enhancement practices, such as stocking, to mitigate anthropogenic stress. However, this is not always the most appropriate management approach. Therefore, there is an urgent need to alter many traditional inland fisheries management practices and systems to focus on sustainable development. This paper reviews the literature regarding the inputs needed for sustainability of inland fisheries in industrialized countries. To understand better the problems facing sustainable inland fisheries management, the inland fisheries environment, its benefits, negative impacts and constraints, as well as historical management, paradigms, trends and current practices are described. Major philosophical shifts, challenges and promising integrated management approaches are envisaged in a holistic framework. The following are considered key elements for sustainable development of inland fisheries: communication, information dissemination, education, institutional restructuring, marketing outreach, management plans, decision analysis, socioeconomic evaluation and research into the human dimension, in addition to traditional biological and ecological sciences. If these inputs are integrated with traditional fisheries management practices, the prospects for sustainability in the inland fisheries will be enhanced. [source]


Land use change and the dependence of national priority species on protected areas

GLOBAL CHANGE BIOLOGY, Issue 9 2008
SARAH F. JACKSON
Abstract The establishment and maintenance of a system of protected areas is central to regional and global strategies for the conservation of biodiversity. The current global trend towards human population growth and widespread environmental degradation means that such areas are becoming increasingly isolated, fragmented habitat islands. In regions in which this process is well advanced, a high proportion of species are thus predicted to have become restricted to protected areas. Here, using uniquely detailed datasets for Britain, a region with close to the global level of percentage coverage by statutory protected areas, we determine the extent of restriction of species of conservation concern to these areas. On the basis of currently known distributions, more than a half of such species are highly dependent on protected areas for their continued persistence, occurring either entirely or largely within their bounds. Such coverage is of particular importance for those species with narrower distributions, and therefore, under the greatest threats, underlining the vital importance of adequately resourcing, maintaining, and developing protected areas to prevent these species from being lost. [source]


Functional biotic homogenization of bird communities in disturbed landscapes

GLOBAL ECOLOGY, Issue 2 2008
Vincent Devictor
ABSTRACT Aim, Worldwide, functional homogenization is now considered to be one of the most prominent forms of biotic impoverishment induced by current global changes. Yet this process has hardly been quantified on a large scale through simple indices, and the connection between landscape disturbance and functional homogenization has hardly been established. Here we test whether changes in land use and landscape fragmentation are associated with functional homogenization of bird communities at a national scale. Location, France. Methods, We estimated functional homogenization of a community as the average specialization of the species present in that community. We studied the spatial variation of this community specialization index (CSI) using 1028 replicates from the French Breeding Bird Survey along spatial gradients of landscape fragmentation and recent landscape disturbance, measured independently, and accounting for spatial autocorrelation. Results, The CSI was very sensitive to both measures of environmental degradation: on average, 23% of the difference in the CSI values between two sample sites was attributed to the difference in fragmentation and the disturbance between sites. This negative correlation between CSI and sources of landscape degradation was consistent over various habitats and biogeographical zones. Main conclusions, We demonstrate that the functional homogenization of bird communities is strongly positively correlated to landscape disturbance and fragmentation. We suggest that the CSI is particularly effective for measuring functional homogenization on both local and global scales for any sort of organism and with abundance or presence,absence data. [source]


Multi-level Environmentalism and the European Union: The Case of Trans-European Transport Networks

INTERNATIONAL JOURNAL OF URBAN AND REGIONAL RESEARCH, Issue 1 2006
HEIN-ANTON VAN DER HEIJDEN
In the European Union, trans-European transport networks (TENs) are a vital element in the constitution of one European space in order to enable the free movement of people and goods throughout the Union. Their construction, however, often causes environmental degradation. Opposition to EU politics is mostly voiced at the level of individual nation-states. As the case of TENs reveals, however, protest against European policy projects with environmental side effects can take the form of ,multi-level environmentalism', linking lobbying and ,conscientization' in Brussels with direct action at the national and local levels. Civil society theory, social movement theory and governance theory help ensure a theoretically informed answer to the question of how the resistance to TENs is organized and framed. By questioning dominant problem definitions and solution strategies, environmental movements and movement organizations, both in Brussels and in the individual nation-states, point to the possibility of looking at social and political reality from another, non-hegemonic point of view. In this way, they contribute to challenging the often biased technocratic, growth-oriented character of the European Union. [source]


A sceptical view of climate change and water resources planning

IRRIGATION AND DRAINAGE, Issue 3 2001
Geoff Kite
changement du climat; l'aménagement des ressources en eau Abstract Journals, both academic and otherwise, are full of papers describing in detail the impacts of climate change, and a presumed causal link to man's activities, especially the contribution of "greenhouse gases". Despite the abundance of funding to study the hypothesised anthropogenic link, it has yet to be demonstrated, while evidence to the contrary can readily be derived from available data. This brief paper summarises some information that may give cause for thought and suggests that environmental degradation should be of more concern than an imaginary climate change. Copyright © 2001 John Wiley & Sons, Ltd. Aujourd'hui les journaux (scientifiques inclus) sont pleins d'articles qui décrivent en détail les effets du changement du climat et qui présentent ses effets comme un résultat des activités anthromorphiques, en particulier notre effet sur les "greenhouse gases". Même avec tout l'argent dépensé de ces études, il n'y a aucune évidence pour cette hypothèse. Au contraire, les données suggèrent que le changement actuel du climat est, pour la grande plupart, naturel. Cet article bref donne un point de vue un peu différent qui constate, en bréf, que bien sûr il y a toujours des changements du climat mais pour l'aménagement des ressources en eau il y a, au moins, un problème plus important. Copyright © 2001 John Wiley & Sons, Ltd. [source]


Relay Cropping of Sorghum and Legume Shrubs for Crop Yield Improvement and Striga Control in the Subsistence Agriculture Region of Tigray (Northern Ethiopia)

JOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 1 2005
F. Reda
Abstract Striga hermonthica is a major constraint in the subsistence agriculture regions of northern Ethiopia. Low soil fertility and overall environmental degradation has contributed to the build up of the parasitic weed infestation. Improved cropping systems have to be introduced to address the interrelated problems of Striga and soil fertility decline. Thus, relay cropping of sorghum with legume shrubs was investigated at two locations representing different environments. Results showed that the output of the improved cropping system was dependent on ecological endowments. Relay cropping led to significant improvement in yield at Sheraro, at the site with relatively better weather and soil conditions. The legume shrubs resulted in significantly lower sorghum yield in a dryland location (Adibakel). Overall Striga infestation declined over the 3-year period; however, treatment differences were not apparent. Among the two legume shrubs, Sesbania sesban was better adapted to the dryland areas. Relay cropping could provide a viable option for farmers in both types of environments that are characterized by accelerated decline in natural resource base. However, it could mean compromising the yield of non-fertilized sorghum in the interest of long-term benefits of low incidence of Striga and more rewarding crop enterprise in dry areas. [source]


Offshore renewable energy: ecological implications of generating electricity in the coastal zone

JOURNAL OF APPLIED ECOLOGY, Issue 4 2005
ANDREW B. GILL
Summary 1Global-scale environmental degradation and its links with non-renewable fossil fuels have led to an increasing interest in generating electricity from renewable energy resources. Much of this interest centres on offshore renewable energy developments (ORED). The large scale of proposed ORED will add to the existing human pressures on coastal ecosystems, therefore any ecological costs and benefits must be determined. 2The current pressures on coastal ecology set the context within which the potential impacts (both positive and negative) of offshore renewable energy generation are discussed. 3The number of published peer-review articles relating to renewable energy has increased dramatically since 1991. Significantly, only a small proportion of these articles relate to environmental impacts and none considers coastal ecology. 4Actual or potential environmental impact can occur during construction, operation and/or decommissioning of ORED. 5Construction and decommissioning are likely to cause significant physical disturbance to the local environment. There are both short- and long-term implications for the local biological communities. The significance of any effects is likely to depend on the natural disturbance regime and the stability and resilience of the communities. 6During day-to-day operation, underwater noise, emission of electromagnetic fields and collision or avoidance with the energy structures represent further potential impacts on coastal species, particularly large predators. The wider ecological implications of any direct and indirect effects are discussed. 7Synthesis and applications. This review demonstrates that offshore renewable energy developments will have direct and, potentially, indirect consequences for coastal ecology, with these effects occurring at different scales. Ecologists should be involved throughout all the phases of an ORED to ensure that appropriate assessments of the interaction of single and multiple developments with the coastal environment are undertaken. [source]


Climate variability and change over southern Africa: impacts and challenges

AFRICAN JOURNAL OF ECOLOGY, Issue 2009
Alec Sithole
Abstract In this paper, the influence of climate variability and change on the environment was studied over southern Africa using ground-based and remotely sensed data. A time series analysis of rainfall and temperature anomalies indicated that there was a high rainfall and temperature variability in the region. The influence of global teleconnections on rainfall patterns over southern Africa showed that in some areas there was a spatial variation in their strength, increasing from west to east. Maps of NDVI, from 1982 to 2004, showed that changes in vegetation cover were more apparent during the dry season than during the wet season. The study also revealed that climate variability and change are linked to decreasing rainfall and hence, decreasing regional water resources and biodiversity and increasing environmental degradation. With the regional population expected increase, this depletion of resources poses the greatest regional environmental challenge to humankind. [source]


Vegetation dynamics in western Uganda during the last 1000 years: climate change or human induced environmental degradation?

AFRICAN JOURNAL OF ECOLOGY, Issue 2009
Julius B. Lejju
Abstract A multi-proxy analysis of microfossils from sedimentary records, together with evidence from historical and archaeological data, has provided evidence of vegetation dynamics and human environment interactions in western Uganda for the last 1000 years. Pollen, fungal spores and phytoliths extracted from sediment cores obtained from a papyrus swamp at Munsa archaeological site indicate a relatively wet and forested environment in western Uganda prior to ca 1000 yr bp (cal 977,1159 ad). A subsequent decline in forest vegetation occurred from ca 920 yr bp (cal 1027,1207 ad). However, the deforestation period occurred during a wet period as registered in the River Nile water records, suggesting a human induced deforestation at Munsa rather than reduced precipitation. Increased numbers of herbivores, presumably domesticated cattle, postdeforestation are evidenced by the presence of dung fungal spores and broad accord with the archaeological evidence for initial occupation of the site at Munsa and the establishment of a mixed economy based on crops, cattle and iron working between 1000 and 1200 ad. From ca 200 yr bp (cal 1647,1952 ad), forest recovery occurred at Munsa site and appears to reflect abandonment of the site, as suggested by archaeological evidence, possibly following a period of prolonged drought and famine between 1600 and 1800 ad, as recounted in the oral rich traditions of western Uganda and also reflected by low water levels of River Nile. [source]


The implications of improved communications for participatory forest management in Tanzania

AFRICAN JOURNAL OF ECOLOGY, Issue 2009
Elizabeth J. Z. Robinson
Abstract Following the 1998 National Forest Policy and Forest Act of 2002, participatory forest management (PFM) is being introduced in Tanzania. PFM has two key objectives: to reduce forest degradation thereby increasing ecosystem services, and to improve the livelihoods of local villagers. A unique data set collected in 2006 suggests that significant challenges remain with respect to communicating the new forest policies if the objectives of PFM are to be achieved. First, villagers as a group are much less well informed than other stakeholders, and their knowledge is often inaccurate. Second, women are less likely than men to have heard of the changes. Third, how PFM will contribute to poverty reduction (a key objective of PFM) is not always clear. Fourth, environmental degradation may not be reduced as much as anticipated , without alternatives sources, villagers often continue to cut trees for charcoal and firewood in the protected forests. Finally, several mismatches in perceptions are identified that could lead to difficulties in implementing PFM. [source]


Ecological, environmental and socioeconomic aspects of the Lake Victoria's introduced Nile perch fishery in relation to the native fisheries and the species culture potential: lessons to learn

AFRICAN JOURNAL OF ECOLOGY, Issue 2 2007
John S. Balirwa
Abstract Inland fishery ecosystems in Africa are characterized by patterns of overexploitation, environmental degradation and exotic species introductions. Ecological complexity and diversity of aquatic habitats dictate that fishes in general are not evenly distributed in a water body. However, fisheries management regimes tend to ignore this basic principle, assume generalized conditions in a water body, and focus more on ,desired' objectives such as maximizing catch. The result is to disregard fish habitat boundaries and anthropogenic influences from the catchment that influence fish production. Overexploitation and environmental degradation disrupt sustainable socioeconomic benefits from the fisheries, create uncertainty among investors, but leave some managers calling for more information with the expectation that the fisheries will recover with time. Open access to the fisheries and full control of fishing effort remain challenges for managers. Exotic species introductions and fish farming can increase production, but such interventions require firm commitment to sound ecological principles and strict enforcement of recommended conservation and co-management measures in capture fisheries. The general tendency to downplay fishing effort issues, other ecosystem values and functions or rely on temperate fisheries models until a new cycle of overexploitation emerges, characterizes many management patterns in inland fisheries. Aquaculture is not an option to challenges in capture fisheries management. Aquaculture should be developed to increase fish production but even this practice may have negative environmental impacts depending on practice and scale. Decades of information on Lake Victoria fisheries trends and aquaculture development did not stop the collapse of native fisheries. The successfully introduced Nile perch (Lates niloticus) has shown signs of overexploitation and aquaculture has again been considered as the option. By reviewing significant trends associated with Nile perch and its feasibility in aquaculture this paper uses Lake Victoria to illustrate ,special interest management' targeting selected species of fish rather than the fisheries. Résumé Les écosystèmes africains où se pratique la pêche intérieure se caractérisent par des schémas de surexploitation, de dégradation environnementale et d'introductions d'espèces exotiques. La complexité et la diversité des habitats aquatiques impliquent que les poissons ne sont, en général, pas distribués de façon uniforme dans une entité aquatique. Pourtant, les divers régimes de gestion des pêcheries tendent à ignorer ce principe élémentaire, présument de conditions uniformes dans une entité aquatique et visent plus les objectifs « souhaités », comme des prises maximales. Le résultat, c'est que l'on ne tient pas compte des limites de l'habitat des poissons et des impacts anthropiques du bassin versant qui influencent la production de poisson. La surexploitation et la dégradation de l'environnement compromettent les bénéfices socio-économiques durables de la pêche, engendrent l'incertitude parmi les investisseurs et font que certains gestionnaires sollicitent plus d'informations dans l'attente que la pêche se redresse avec le temps. L'accès libre à la pêche et le contrôle total des efforts de pêche restent de vrais défis pour les gestionnaires. Les introductions d'espèces exotiques et les fermes piscicoles peuvent augmenter la production, mais ces interventions exigent un engagement solide vis-à-vis des principes écologiques responsables et l'application stricte des mesures de conservation et de co-gestion recommandées pour la pêche. La tendance générale à minimiser les problèmes des efforts de pêche et les autres valeurs et fonctions de l'écosystème, ou à se baser sur des modèles de pêche tempérés jusqu'à ce qu'un nouveau cycle de surexploitation émerge, caractérise de nombreux schémas de gestion de pêche intérieure. L'aquaculture n'est pas une option pour les défis auxquels fait face la gestion de la pêche. L'aquaculture devrait être développée pour augmenter la production de poisson, mais même cette pratique peut avoir des impacts environnementaux négatifs dus à l'échelle et à la façon dont on la pratique. Des décennies d'informations sur les tendances de la pêche et le développement de l'aquaculture dans le lac Victoria n'ont pas empêché l'effondrement de la pêche originale. La perche du Nil (Lates niloticus), introduite avec succès montre des signes de surexploitation et l'aquaculture a de nouveau été envisagée. En passant en revue les tendances significatives liées à la perche du Nil et la faisabilité de son aquaculture, cet article se sert du lac Victoria pour illustrer la « gestion d'intérêt spécial » qui vise des espèces de poissons sélectionnées plutôt que la pêche. [source]


The status of fish conservation in South African estuaries

JOURNAL OF FISH BIOLOGY, Issue 9 2010
A. K. Whitfield
Estuary-dependent fish species are defined as those taxa whose populations would be adversely affected by the loss of estuarine habitats. Of the 155 species regularly recorded in South African estuaries, only 32 (21%) are completely dependent on these systems, but this figure increases to 103 species (66%) if partially dependent taxa are included in the analysis. The conservation of fishes in estuaries on the subcontinent is threatened by a number of factors, including habitat degradation, disruption of essential ecological processes, hydrological manipulations, environmental pollution, overexploitation due to fishing activities and, more recently, climate change and the effects of introduced aquatic animals. Although major threats to fishes are usually linked to environmental degradation, there is increasing evidence that the stocks of certain fish species are overexploited or collapsed. Fish conservation and fisheries management does not depend on the implementation of a single action, but rather the co-ordination of a detailed plan, often in a multidisciplinary context. Some examples of innovative means of contributing to estuarine fish conservation in a South African context include the determination and implementation of the ecological freshwater requirements for estuaries, the zoning of estuaries for different uses and the recognition that the maintenance of ecological processes are vital to aquatic ecosystem health. Apart from the designation of protected areas, the main direct means of conserving fish species and stocks include habitat conservation, controls over fishing methods, effort, efficiency and seasonality, pollution control and the prevention of artificial manipulation of estuary mouths. Since becoming a democracy in 1994, environmental legislation, policy and institutional arrangements in South Africa have undergone some major changes, which, if fully implemented, will be very positive for fish conservation in estuaries on the subcontinent. [source]


Horizontal transmission of Beauveria bassiana (Bals.) Vuill

AGRICULTURAL AND FOREST ENTOMOLOGY, Issue 1 2000
David W. Long
Summary 1 Factors influencing horizontal transmission of the entomopathogen Beauveria bassiana in the Colorado potato beetle (CPB) were examined through a series of laboratory studies. 2 Cadaver density, cadaver life stage, ambient temperature and conidial density were the factors manipulated. 3 Mortality and sporulation of burrowing CPB prepupae both increased significantly with increased sporulating second-instar cadaver density on the soil surface. 4 Mortality rates were significantly higher when prepupae were released into laboratory arenas containing third-instar cadavers compared to second-instar cadavers. 5 Mortality and sporulation decreased significantly as temperature increased from 15 °C to 30 °C, however, no temperature-dependent behavioural response by prepupae could be identified as a potential cause. 6 An 86.1% decrease in conidial density per cadaver had no significant effect on mortality or sporulation of prepupae, indicating that this level of environmental degradation of cadavers may not significantly reduce the probability of horizontal transmission. [source]


Novel Composites Constituted from Hafnia and a Polymer-Derived Ceramic as an Interface: Phase for Severe Ultrahigh Temperature Applications

JOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 10 2007
Sudhir Brahmandam
HfO2,SiCN (polymer-derived silicon carbonitride) composites were prepared by two methods. In one case, equal volume fractions of HfO2 and pyrolyzed powders of SiCN were co-sintered, to create a particulate composite. The second type, called interface composites, were prepared by coating HfO2 particles with a thin film of the polymer precursor, followed by sintering so that densification and pyrolysis of the precursor occurred simultaneously; this process results in a ,5-nm-thick grain boundary film constituted from Hf, O, and Si. The fracture properties and environmental degradation (in a humid environment at a velocity of 17.6,35.0 cm/s at 1300°C) of these two composites were measured. They were compared with the properties of a reference material made by sintering HfO2 powders without any additives, under similar conditions (1450°C for 2 h in air). The interface composite yielded the highest sintered density (0.90), exhibited negligible grain growth, and possessed the highest fracture strength (110 MPa). The strength remained immune to hydrothermal oxidation for several hundred hours. In contrast, the particulate composite suffered severe degradation in strength after hydrothermal exposure. The interface composites, with their highly refractory grain boundaries, represent a new class of ceramics for structural applications in harsh environments and at ultrahigh temperatures. [source]


Development of an Index of Biotic Integrity for a Southeastern Coastal Plain Watershed, USA,

JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 2 2007
Charles C. Morris
Abstract:, This study evaluated biological integrity expectations of fish assemblages in wadeable streams for the Alabama portion of the Choctawhatchee River watershed using a multimetric approach. Thirty-four randomly selected stream sites were sampled in late spring 2001 to calibrate an index of biotic integrity (IBI). Validation data were collected during the spring 2001, and summer and fall of 2003 from disturbed and least-impacted targeted sites (n = 20). Thirty-five candidate metrics were evaluated for their responsiveness to environmental degradation. Twelve metrics were selected to evaluate wadeable streams and four replacement metrics were selected for headwater streams. Scores that ranged from 58 to 60 were considered to be representative of excellent biotic integrity (none found in this study), scores of 48-52 as good integrity (31% of the sites in this study), 40-44 as fair (43%), 28-34 as poor (21%), and 12-22 as very poor (5%). Of the four stream condition categories (urban, cattle, row crop, and least impacted), the IBI scores for urban and cattle sites differed significantly from least-impacted sites. Row crop sites, although not significantly different from least-impacted, tended to have greater variability than the other categories. Lower IBI scores at both urban and cattle sites suggest that the IBI accurately reflects stream impairment in the Choctawhatchee River drainage. [source]