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1.
In a meeting between FUNAI (the Brazilian Indian National Foundation) and the Kayapo in the Kayapo village of Aukre, in October 2005, the Kayapo Indians requested support to increase the culture of coconuts (Cocos nucifera) in their lands. The introduction of exotic species is a cause of biological diversity loss throughout the world. However, this is by no means applicable to all kinds of exotic species. We argue that the culture of coconuts may actually be a useful tool for the conservation of this country’s indigenous lands, despite criticism to the contrary. It may also be useful as source for raw material for the indigenous people who are presently experiencing a population boom. For the Kayapo of south-eastern Amazonia, such a demographic explosion, coupled with their increasing dependence on money to purchase industrialized goods, tend to substantially increase the pressure on their lands, which still contain a substantial amount of well-preserved seasonally-dry Amazonian forests. We investigated the actual economic relevance of coconuts for the Kayapo by measuring human and coconut populations and found that this exotic palm is not important for the subsistence of these Indians, due to coconut scarcity, and that such importance is not forthcoming. In the Amazon, coconuts may be particularly useful for the Indians’ nutrition due to the high energetic value of the solid endosperm of the mature fruit. Therefore, given the importance of indigenous lands for the conservation of the Amazonian forests, the encouragement of subsistence coconut cultures in indigenous lands is defensible as a measure for the conservation of biodiversity.  相似文献   

2.
Few would now deny that the use of organobromine compounds to achieve fire retardancy in a diverse array of products and materials has led to contamination of the ecosphere on a widespread scale. This environmental prevalence and persistence of the brominated flame retardants, coupled with growing evidence of their potential for harm, present all too familiar parallels with the previous generation of persistent organic pollutants. Indeed, given the intrinsic properties of these brominated chemicals, the nature and extent of the current problem could well have been predicted in advance. The question is then whether we are prepared to let history repeat itself once more or to take precautionary action now to switch to more sustainable alternatives. The choice facing society is not between brominated flame retardants and unsafe products, but between fire safety leading to global contamination or fire safety achieved in less polluting ways. If we look beyond options for simple chemical-for-chemical substitution to alternative materials and designs, many of the solutions are already available. The remainder could undoubtedly be developed given the incentives to do so. However, a strong and clear policy approach, backed by legislative phase-outs within specified (and challenging) timeframes, will be necessary to break our current dependency on organobromine chemistry. This paper presents the justification for such an approach, reviews those initiatives already underway to replace brominated flame retardants and identifies pathways to the use of more sustainable products in the service of society.  相似文献   

3.
On the basis of Annals of Nature of the Prioksko-Terrasnyi Biosphere Reserve, its colonization by invasive mammal species and the current state of their populations have been analyzed. In the mammal fauna of the reserve, 13 out of 60 species can be classified as invasive. They differ in the degree of impact on the biota. The house mouse, Norway and black rats, and European bison have virtually no effect on natural ecosystems; the effect of the muskrat, raccoon dog, American mink, red and axis deer is insignificant; and that of stray dogs and Tartarian roe deer is considerable. The European beaver and wild boar play an environment-forming role. The impact of beaver activities is strong but local, whereas activities of wild boars put into question the very possibility of conservation and analysis of representative biosphere areas and biological diversity in the reserve.  相似文献   

4.
This paper investigates the explanatory power of development, prosperity and regulatory capability as proximate causes of non-indigenous species (NIS) occurrence in different countries, doing this by statistically analysing a global cross-sectional data set. Since the quantification of development is subject to much discussion, two different indicators are tested: gross domestic product (GDP) per capita and the United Nations human development index (HDI). A corruption index is used as an indicator of regulatory capacity. In addition, variables capturing country openness, which facilitates NIS introduction, and habitat conditions, which determine NIS establishment, are included as explanatory variables. The GDP indicator together with the corruption index fits the NIS data best, where the number of NIS is higher in countries with larger incomes. However, countries with relatively high income but low institutional capacity show a larger number of NIS than countries with a similar level of income but with higher institutional capacity. The results also point to the significant contributions of openness and habitat fragmentation to NIS occurrences in the countries.  相似文献   

5.
Sustainability science is emerging as a transdisciplinary effort to come to grips with the much-needed symbiosis between human activity and the environment. While there is recognition that conventional economic growth must yield to policies that foster sustainable development, this has not yet occurred on any broad scale. Rather, there is clear evidence that the Earth’s ecosystems and landscapes continue to degrade as a consequence of the cumulative impact of human activities. Taking an ecohealth approach to sustainability science provides a unique perspective on both the goals and the means to achieve sustainability. The goals should be the restoration of full functionality to the Earth’s ecosystems and landscapes, as measured by the key indicators of health: resilience, organization, vitality (productivity), and the absence of ecosystem distress syndrome. The means should be the coordinated (spatially and temporally) efforts to modify human behaviors to reduce cumulative stress impacts. Achieving ecosystem health should become the cornerstone of sustainability policy—for healthy ecosystems are the essential precondition for achieving sustainable livelihoods, human health, and many other societal objectives, as reflected in the Millennium Development Goals.  相似文献   

6.
PurposeAnthrax is caused by Bacillus anthracis, which can naturally infect livestock, wildlife and occupationally exposed humans. However, for its resistance due to spore formation, ease of dissemination, persistence in the environment and high virulence, B. anthracis has been considered the most serious bioterrorism agent for a long time. During the last century anthrax evolved from limited natural disease to potentially global threat if used as bioweapon. Several factors may mitigate the consequences of an anthrax attack, including 1. the capability to promptly recognize and manage the illness and its public health consequences; 2. the limitation of secondary contamination risk through an appropriate decontamination; and 3. the evolution of genotyping methods (for microbes characterization at high resolution level) that can influence the course and/or focus of investigations, impacting the response of the government to an attack.MethodsA PubMed search has been done using the key words “bioterrorism anthrax”.ResultsOver one thousand papers have been screened and the most significant examined to present a comprehensive literature review in order to discuss the current knowledge and strategies in preparedness for a possible deliberate release of B. anthracis spores and to indicate the most current and complete documents in which to deepen.ConclusionsThe comprehensive analysis of the two most relevant unnatural anthrax release events, Sverdlovsk in the former Soviet Union (1979) and the contaminated letters in the USA (2001), shows that inhalational anthrax may easily and cheaply be spread resulting in serious consequences. The damage caused by an anthrax attack can be limited if public health organization, first responders, researchers and investigators will be able to promptly manage anthrax cases and use new technologies for decontamination methods and in forensic microbiology.  相似文献   

7.
Consideration is given to the examples of suppression of restorative succession by invasive plant species (Solidago canadensis L., Helianthus subcanescens (A. Gray) E. Watson, Impatiens glandulifera Royle) in anthropogenic landscapes of southeastern Belarus. Characteristics of communities blocking the succession process have been revealed: low species richness, dominance of alien species in coverage, high level of synanthropization, and the absence of natural regeneration of trees and shrubs. It is suggested that a delay in succession is caused by the suppressing influence of transformer species on seed germination in apophytic trees.  相似文献   

8.
9.
In this survey the earth is viewed from the astrophysical perspective, i.e. using global mean values of environmental parameters. The role of carbon dioxide is described in the processes of energy transfer from the earth's surface to space, which determine “global climate” as measured by the mean surface temperature. Analogies and differences between the problems of the terrestrial atmosphere and those of the solar and stellar atmospheres are examines, both in the computation of model atmosphere and in remote sensing of atmospheric temperature and composition. Subsequently, the temporal astrophysical perspective, with a review of the evolution of CO2 abundance and climate on astrophysical or geological time scales, on earth as on Venus (the runaway greenhouse) and on Mars is introduced. Variation of CO2 may have been critical to the maintenance of an environment in which life could originate and evolve, and may itself have been affected by life. On human time scales, the recent and continuing increase in atmospheric CO2 raises new problems, which are briefly surveyed. It is argued, that the differential greenhouse effect of increased CO2 in the earth's atmosphere is essentially identical to the “blanketing effect” of spectral lines on the temperature structure of stellar atmospheres. The methods used by astrophysicists in such studies are reviewed and compared with those used to evaluate the differential greenhouse effect of CO2 in radiative-convective models of the earth's atmosphere. The latter methods remain relatively crude, but recent results by different authors are in reasonably good agreement; however, the astrophysical perspective, i.e. the use of one-dimensional global mean models, remains a gross simplification of the real complexity of the earth's climate system, which is also true in stellar atmospheres.  相似文献   

10.
Environment, Development and Sustainability - This study assessed the vulnerability of five indigenous agroforestry trees to climate change: Adansonia. digitata, Vitellaria paradoxa, Parkia...  相似文献   

11.
This research examines how the Kandozi indigenous group governs access to fish and timber for sale and evaluates their perceptions of sustainability of those natural resources. The Kandozi occupy a biodiverse tropical forest in the northern Peruvian Amazon with lakes and seasonally flooded areas. Qualitative methods and a comparative examination of access to resources were used to explore current processes that shape access and the people’s perceptions of their benefit from natural resources. Results indicated that environmental heterogeneity, kinship, land tenure, the legal framework, and knowledge all shaped access with some differences due to the dissimilar natures of fish and timber. This research concludes that the sustainability of this and similar systems are dependent upon the moment at which the analysis is done, because of the changing needs of people over time, in addition to changes in external factors and the natural variations that occur in the resources used. The range of relations and interactions among different processes that shape access, and the historically contingent characteristic of access and its evolution over time, help better understand the complexity of a given social-ecological system.  相似文献   

12.
A view of pollination systems is that they tend to generalization. Here we show that patterns exist in pollination systems that suggest otherwise. We examine how specialization may be affected by latitude, species richness and plant life-forms in 33 plant-pollinator interaction networks. Connectance increases with latitude (P = 0.040), but specialization at the community level significantly declines with increasing latitude, with the strongest evidence in the Northern Hemisphere (P = 0.001). The relationship between specialization level and connectance is negative (P < 0.001). While plants are more specialized in tropical areas and are more generalized at higher latitudes, specialization level also increases with plant richness (P < 0.001), total species richness (P = 0.041) and network size (P = 0.009). Specialization level of life forms of 1129 species differ substantially (P < 0.001), with herbs showing the highest specialization (74%), and tree species the lowest (62%).  相似文献   

13.
The aim of this study was to determine whether the latitudinal distribution of fish species that use estuaries to complete their entire life cycle has shifted northward as an expected consequence of global warming. The mean latitude of past fish species distributions found in 1970s’ literature was compared with the mean latitude of distributions today based on fish density indices collected in 55 tidal estuaries along the Atlantic European seaboard, from Portugal to Scotland. Among the 15 most common species, 11 displayed a positive difference between current and past mean latitudes suggesting a northward shift of the populations. Using the occurrence of subtropical species in temperate areas as an indicator of water warming, the northernmost range limit of 10 subtropical species was subsequently focused on. Six of them were recorded up to their past northern latitudinal limit. These results reinforced the idea that a number of fish species associated to estuaries have migrated northwards over the last 30 years, possibly due to water warming. These ecological changes can get important managerial implications, i.e. in the assessment of the ecological status in European directives.  相似文献   

14.
Policy development related to marine protected areas (MPAs) occurs at three levels: international, national, and local. Recent developments with MPAs highlight their close links to broader national-level park and protected area policies, which in turn take their lead from initiatives and recommendations initiated, and increasingly dictated, by international organizations. Local-level inputs to MPA policies have tended to be limited to the immediate local area context despite the vital importance of community-level support and knowledge in meeting broader regional goals of marine conservation tied to networked MPAs. In this paper, we highlight the mechanisms to facilitate cooperation and communication among international, national, and local levels of policy and practice needed to address this deficit. These include the creation of a social network of institutions that both internationalizes and localizes MPA policy development, facilitating a more meaningful engagement of local people through their legitimate participation in national and international MPA gatherings. In addition, mechanisms to formalize partnerships, feedback information, resolve conflicts, and report accountabilities are needed. The success of the latter will depend on the level of recognition and support given to community-level institutions as opposed to the suite of technical training and short-term project-based interventions that have characterized local support over recent decades.  相似文献   

15.
Specific structural features of absorbing roots have been studied in Acer negundo (an invasive species in the southern Cisural region), compared to native Acer platanoides and A. tataricum. A comparative analysis of the diameter of fine roots, stele and bark volumes, and the frequencies of roots with retained primary bark, root hairs, arbuscular mycorrhiza, and dark septate endophytes has been performed in the invasive and native species from four habitats (by two habitats in the forest–steppe and steppe zones). The roots of A. negundo have been additionally studied in trees from two monospecific stands. It has been found that the structure of fine roots significantly differs between the invasive and native species: the roots of A. negundo are larger, with relatively poorly developed root hairs and low occurrence of dark septate endophytes. In monospecific stands, the frequency of mycorrhiza in A. negundo roots is very low, with arbuscules and dark septate endophytes being totally absent. It is concluded that specific structural features of the belowground absorbing apparatus in A. negundo are accounted for mainly by traits autonomously formed in a plant, rather than by characteristics of symbiotic relationships, and that they are not consistent with the assumption that the invasive species can utilize soil resources more effectively or more rapidly than taxonomically close native species.  相似文献   

16.
The present work seeks to assess the sustainability of different solar photovoltaic (SPV) electricity-generating systems based upon energy, environment and economics. The sustainability indicators evaluated for energy, environment and economics are electrical output, life-cycle greenhouse gas (GHG) emissions and life-cycle cost of electricity generated per kilowatt hour. The selected SPV-based electricity generation technologies for sustainability evaluation are amorphous, monocrystalline and polycrystalline at different locations and tilt angles across India. For SPV systems, most of the emissions are the result of electricity use during manufacturing. In these cases, an average grid mix for the region of manufacture is typically used to calculate energy use and emissions. Based upon these three indicators, a figure of merit (FM) has been proposed. The results proposed that polycrystalline gives the maximum electrical output, minimum GHG emission, minimum cost and maximum FM at a radiation level of 6 kWh/m2/day with latitude and tilt angle of 34° and 35°, respectively. This work will be helpful to users of solar energy, academicians, researchers and other concerned persons, in understanding the importance, severity and benefits obtained by the application and implementation of the SPV electricity-generating systems.  相似文献   

17.
Environment, Development and Sustainability - Consumers’ interest is accelerating toward environmentally sustainable products, which are commonly known as green products. Companies use...  相似文献   

18.
19.
The causes and ecological consequences of alien plant species invasions in the Southern Urals are analyzed. Aggressive invasive species of North American origin??Ambrosia trifida L., A. psylostachya DC., Cyclachaena xanthiifolia (Nutt.) Fresen., Hordeum jubatum L., Oenothera biennis L., Bidens frondosa L., etc.??have invaded synanthropic and natural plant communities and became dominant, with their proportion varying from 10 to 99%. The biomass of these plants may reach 6 kg/m2; density, more than 1000 shoots per square meter; and seed production, up to 30000 seeds per plant, which explains their dominance in communities. The ecological hazard they pose lies in the displacement of native species, overgrowing of disturbed land areas, and allergenicity of their pollen.  相似文献   

20.
International projects frequently struggle with the dilemmas of community participation, whether the community in question is the object of a development or aid intervention, or is to be persuaded to cooperate on a conservation project. This paper discusses the challenges facing interventionists and the obstacles and opportunities that local people encounter as they come into contact with exogenous conservation and development projects. The key issues presented can be summarized as legacy, legitimacy, agency and communication. We argue that project planners need to understand the history of past interventions in order to respond appropriately to local expectations. At the same time, the complexity of community leadership and representation complicates the sometimes conflicting agendas of project developers and communities. Much depends on personal relations, individual agency, and initiative. Finally, the physical means of communication—language, print and broadcast media, transport and telecommunications—are important aspects to consider when assessing the limitations to community participation. Although there have been valuable successes in international projects in Russia, as in other regions of the world, a better understanding of community participation is needed to ensure more effective and sustainable means for engaging communities in project development and implementation. This paper explores these questions through a locally-grounded analysis based on the academic research and practitioner experience of the two authors in the remote home of a World Heritage site—the Kamchatka Peninsula, in the Russian Far East.  相似文献   

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