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101.
Abstract: The demographic impacts of harvesting nontimber forest products (NTFP) have been increasingly studied because of reports of potentially unsustainable harvest. Nevertheless, our understanding of how plant demographic response to harvest is altered by variation in ecological conditions, which is critical for developing realistic sustainable‐use plans, is limited. We built matrix population models to test whether and how variation in ecological conditions affects population responses to harvest. In particular, we examined the effect of bark and foliage harvest on the demography of populations of African mahogany (Khaya senegalensis) in two contrasting ecological regions of Benin, West Africa. K. senegalensis bark and foliage harvest significantly reduced its stochastic population growth rates, but ecological differences between regions had a greater effect on population growth rates than did harvest. The effect of harvest on population growth rates (Δλ) was slightly stronger in the moist than in the drier region. Life‐table response experiments revealed that the mechanism by which harvesting reduced λ differed between ecological regions. Lowered stasis (persistence) of larger life stages lead to a reduction in λ in the drier region, whereas lowered growth of all life stages lowered λ in moist region. Potential strategies to increase population growth rates should include decreasing the proportion of individuals harvested, promoting harvester‐owned plantations of African mahogany, and increasing survival and growth by promoting no‐fire zones in gallery forests. Our results show how population responses to harvest of NTFP may be altered by ecological differences across sites and emphasize the importance of monitoring populations over the climatic range in which they occur to develop more realistic recommendations for conservation. 相似文献
102.
Danielle Tessaro 《国际发展与全球生态学杂志》2013,20(5):471-479
In South Africa, extreme rural poverty often geographically overlaps with areas of high and important biodiversity. Attempts to bring about land-based poverty reduction projects in such areas tends to trigger tensions among stakeholders purporting to be concerned about local people’s welfare, as well as the environment. Using discursive document analysis and semi-structured interviews, the paper discusses a case study of the Wild Coast, an area celebrated for its high biodiversity and ‘beauty’, which reveals that a tension among environmental non-government organisations, government agencies and the private sector, on the best development option, exacerbates the threats to local livelihood options and biodiversity conservation. 相似文献
103.
《Environmental Communication: A Journal of Nature and Culture》2013,7(2):206-224
Tourism is the way we understand the world: tourists travel in an increasingly mediated environment in which ubiquitous promotional material and other popular artifacts employ stunning images and romantic travel narratives to describe local environments. Tourist texts “sell” local landscapes to entice visitors, employing an environmental aesthetic that urges travel. With its mission to “explore the planet,” the National Geographic Society contributes to this tourist aesthetic. This essay examines three special issues on Africa simultaneously published by the National Geographic Society: its official journal, National Geographic, and its sister magazines, National Geographic Traveler, and National Geographic Adventure. The photographic images and travel narratives in these tourist texts produce an environmental aesthetic that positions the traveler at the center of these environments. This essay first analyzes how National Geographic constructs Africa's environmental landscapes. These magazines depict Africa as a vast desert plain, a wilderness theme park, and a part of the global scenery. The second part of the analysis examines how National Geographic locates the tourist in these environments. I discuss how National Geographic positions the tourist as protagonist, expert, and hero of Africa's environment. In the conclusions, I argue this environmental aesthetic renders Africa invisible through anthropocentric distance, and I discuss the need for more critical readings of tourist discourse. 相似文献
104.
This paper explores a fruitful convergence between the distributive and procedural dimensions of environmental justice theory and current debates in the field of development studies over capitals and capabilities, institutions, and discourse formation to shed new light on natural resource management projects in the developing world. Specifically, we document the planning and implementation of two types of water interventions in two contrasting regions: watershed development programmes in northeast India and small reservoirs in sub‐Saharan West Africa. We find that there is a contradiction between the inherently political nature of water interventions and the fact that such projects remain grounded in apolitical, technical and managerial narratives. In contrast to the new semantic of development, this depoliticization results in the near absence of attention paid to procedural (participation and empowerment) and distributive (equity) justice concerns and in local actors having to revert to covert ways to achieve their ends. A constructive dialogue between development studies and environmental justice scholars can offer a fresh look on the society‐environment nexus in the developing world. 相似文献
105.
Robert B. Kehew Mthobeli Kolisa Christopher Rollo Alejandro Callejas Gotelind Alber Liana Ricci 《Local Environment》2013,18(6):723-737
Faced with the prospects of a changing climate, a small but increasing number of countries are developing legal and regulatory frameworks that explicitly address climate change. Moreover at least some of these laws and policies carve out substantial roles for local governments. The present paper surveys three countries from different regions in the Global South that have developed or are developing such laws and policies: the Philippines (Asia-Pacific), Mexico and more specifically its State of Chiapas (Latin America), and South Africa (Africa). It examines those experiences through two different lenses. The paper first reviews the steps by which those laws or policies were developed. For this review, criteria for effective consultative processes are proposed. The study then examines the three climate change laws or policies per se. To this end, a framework including four modes of multi-level urban climate governance (governing by regulation, governing through enabling, governing by provision, governing with representation and consultation) is utilised. The paper ends with synthetic conclusions as to which experiences represent promising practices, and what other lessons are relevant for countries embarking on such processes. 相似文献
106.
Snoussi M Kitheka J Shaghude Y Kane A Arthurton R Le Tissier M Virji H 《Environmental management》2007,39(5):587-600
Anthropogenic factors associated with damming and water abstraction, and the resultant environmental pressures, are reviewed
in six African river catchments using records and forecasts of climatic, demographic, and land-use change. Changes in the
states of the flow regime through catchment drainage systems to the coastal sea are considered in conjunction with climate
change and other human-induced pressures. The impacts of these changes on downstream and coastal environments and their communities
are described in past, present, and future perspectives. Linkages between the issues and the pressures of damming and water
abstraction are appraised and scientific, policy, and management responses proposed aimed at remedying existing and perceived
future negative impacts. The study proposes that there is a need to integrate catchment and coastal management to account
for the whole water flow regime together with its human dimensions. Management priorities relating to the operation of existing
damming and abstraction schemes and planning of future schemes include the following: consideration of ways in which water
discharges could be adjusted to provide improvements in downstream and coastal environmental and socioeconomic conditions;
addressing the problem of sediment trapping impacting on the sustainability of dam reservoirs; and assessment of downstream
and coastal impacts of future schemes in the light of climate change forecasts. 相似文献
107.
This paper presents the results of research which evaluated the performance of strategic environmental assessment (SEA) practice in South Africa in order to develop understanding of how SEA functions within a developing country with a voluntary SEA system. The research applied a combination of methods in a mixed research strategy, including a macro level survey of the SEA system together with case study reviews exploring micro level application. Three main ‘system features’ emerged, namely expansion of voluntary practice, diversity in practice and general ineffectiveness. The results also highlight a number of ‘application features’ such as a lack of focus due to an inability to deal with the concepts of ‘sustainability’ and ‘significance’, as well as poor understanding and integration with decision-making processes. Moreover, it emerged that none of the case studies seem to have conducted an ‘assessment’ per se, but rather provided a framework for strategic decision-making. The paper puts forward a number of interrelated explanations for these system and application features. In a parallel to the fable of the ‘emperor's new clothes’, SEA in South Africa appears to be regarded as the answer to all environmental problems, whilst being ineffective in practice. 相似文献
108.
R. A. Hope 《Environment, Development and Sustainability》2006,8(1):139-156
In 1995, the government of the Republic of South Africa launched the Working for Water (WfW) programme that links environmental
and developmental goals through the removal of high water-consuming alien plants with pro-poor rural employment opportunities.
Whilst bio-physical evaluations have widely reported on the hydrological, ecological and conservation components of the programme,
there exists growing uncertainty over the programme’s role as a poverty reduction mechanism. This paper evaluates three projects
in the Luvuvhu catchment, Limpopo Province, against five socio-economic workfare criteria and the underlying biophysical rationale.
Results show that asset creation from incremental streamflow is economically efficient and is likely to improve significantly
if biodiversity benefits, community harvesting of riparian goods and services, ecological non-use values and seasonal water
demand values are incorporated into the analysis. However, socio-economic benefits are more questionable: poverty targeting
is weak with wage rates failing to self-select the poor; a minor proportion (0.5%) of catchment households benefit from the
highly-valued employment opportunities; high variability in monthly employment causes financial difficulties for labourers;
labourers are not ‘empowered’ as is evidenced by the failure of the 2-year exit strategy; and programme efficiency is high
in proportional allocation of cash-flow to non-management wage labour. It is concluded that the Working for Programme is a
potentially replicable model in other semi-arid contexts in developing countries if based on its core biophysical remit but
is a transitory and limited poverty reduction mechanism for improving rural livelihoods. 相似文献
109.
In this paper, consideration has focused mainly on the extent and usefulness of the existing literature available so far on the understanding of the impact of climate change on water resources in Africa, focusing mainly on the Olifants River basin in South Africa. Here, the existing literature on the impact of climate change on the hydrological cycle (particularly the hydrological processes like temperature, precipitation and runoff) has been reviewed. The uncertainties, constraints and limitations in climate change research have been discussed at great length. A detailed discussion has been highlighted on the remaining knowledge gaps in climate change research, especially in Africa. In addition to the research gaps highlighted here, the emphasis on the need of climate change research by African scientists is included as part of lessons learnt. Overall, the importance of conducting further research in climate change, understanding the potential impact of climate change on our lives, and taking actions to effectively meet the adaptation needs of the people, emerge as an important theme in this review. 相似文献
110.
Dennis D. Mwanza 《Environment, Development and Sustainability》2003,5(1-2):95-115
Water is a precious yet non-renewable resource. Yet in Africa, the same water can be a source of life and death. Water is not only the most basic of need but also at the centre of sustainable development and essential for poverty eradication. Water is intimately linked to health, agriculture, energy and biodiversity. Without progress on water, reaching other Millennium Development Goals (MDGs) will be difficult if not impossible. The fight against poverty will remain a pipe dream.A lot of activities have been undertaken with the aim of highlighting the importance of water, linking water with sustainable development and indeed developing strategies for resolving the ever-increasing problems of water. These include the adoption of the Africa Water Vision in The Hague, Netherlands in March, 2000.In order to address the many problems of water in Africa especially related to the coordination of the increasing number of initiatives in the Water sector in Africa, the African Water Task Force (AWTF) was established.As part of developing solutions to the African water crisis, the AWTF held a regional conference in Accra Ghana. Some of the emerging issues from the Accra Conference are highlighted in the Accra declaration.This paper highlights the linkages between water and sustainable development, water and poverty and the many facets that relate to water. It mainly addresses issues of water from the African perspective. A number of key events that have taken place and which have served as a basis for many policy pronouncements have been given.The last section concentrates on what happened to water at the World Summit for Sustainable Development (WSSD) held in Johannesburg in September 2002. 相似文献