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261.
Despite the large implications of the use of tropical land for exports (“land absorption”) on ecosystem services (ES) and global biodiversity conservation, the magnitude of these externalities is not known. We quantify the net value of ES lost in tropical countries as a result of cropland, forestland and pastureland absorption for exports after deducting ES gains through imports (“land displacement”). We find that net ES gains occur only in 7 out of the 41 countries and regions considered. We estimate global annual net losses of over 1.7 x 1012 international dollars (I$) (I$1.1 x 1012 if carbon-related services are not considered). After deducting the benefits from agricultural, forest and livestock rents in land replacing tropical forests, the net annual losses are I$1.3 and I$0.7 x 1012, respectively. The results highlight the large magnitude of tropical ES losses through international trade that are not compensated by the rents of land uses in absorbed land.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-016-0768-7) contains supplementary material, which is available to authorized users.  相似文献   
262.
National Park Development in China: Conservation or Commercialization?   总被引:1,自引:0,他引:1  
Wang G  Innes JL  Wu SW  Krzyzanowski J  Yin Y  Dai S  Zhang X  Liu S 《Ambio》2012,41(3):247-261
The rapid development of parks and ecotourism in China has attracted worldwide attention, not only for the beauty of the landscape that the parks are protecting but also for their abundant and often unique biodiversity. However, in some areas, the development of ecotourism has actually led to the degradation of local ecological, economic, and social systems. Using National Forest Parks for demonstration, this article analyzes the current political, institutional, legal, environmental, and economic issues concerning National Parks in China, and examines their potential future development. Although the intention of National Park systems in China is to raise environmental quality, and to protect biodiversity and social livelihoods, their success has varied. Future success will be measured by their capacity to reduce poverty, to promote long-term rehabilitation of wildlife habitats, and to simultaneously protect Chinese culture and biodiversity.  相似文献   
263.
Based on the norm activation theory we developed assumptions about how parents may influence specific pro-environmental behaviours (i.e. re-use of paper and recycling) of their children (age 8–10). A sample of 206 parent-child-dyads were investigated using questionnaires recording norm activation model variables for children (i.e. awareness of need, awareness of consequences, personal norm, subjective norm, pro-environmental behaviour), as well as communication behaviour and actual behaviour of parents. For both behaviours (re-use and recycling) two separate structural equation models were tested (N = 206 and N = 194). Model fit statistics indicate a good fit of empirical data and model structure for both behaviours, supporting our assumption that the norm activation model can be applied to pro-environmental behaviour of young children. Communication behaviour of parents had a different influence on the two respective behaviours. While parents seemed to influence their children's recycling behaviour via sanctions and their own behaviour, re-use of paper was mainly influenced via communication of problem knowledge.  相似文献   
264.
Like many developing countries, Nepal has adopted a community-based conservation (CBC) approach in recent years to manage its protected areas mainly in response to poor park–people relations. Among other things, under this approach the government has created new “people-oriented” conservation areas, formed and devolved legal authority to grassroots-level institutions to manage local resources, fostered infrastructure development, promoted tourism, and provided income-generating trainings to local people. Of interest to policy-makers and resource managers in Nepal and worldwide is whether this approach to conservation leads to improved attitudes on the part of local people. It is also important to know if personal costs and benefits associated with various intervention programs, and socioeconomic and demographic characteristics influence these attitudes. We explore these questions by looking at the experiences in Annapurna and Makalu-Barun Conservation Areas, Nepal, which have largely adopted a CBC approach in policy formulation, planning, and management. The research was conducted during 1996 and 1997; the data collection methods included random household questionnaire surveys, informal interviews, and review of official records and published literature. The results indicated that the majority of local people held favorable attitudes toward these conservation areas. Logistic regression results revealed that participation in training, benefit from tourism, wildlife depredation issue, ethnicity, gender, and education level were the significant predictors of local attitudes in one or the other conservation area. We conclude that the CBC approach has potential to shape favorable local attitudes and that these attitudes will be mediated by some personal attributes.  相似文献   
265.
Agricultural productivity growth is vital for economic and food security outcomes which are threatened by climate change. In response, governments and development agencies are encouraging the adoption of ‘climate-smart’ agricultural technologies, such as conservation agriculture (CA). However, there is little rigorous evidence that demonstrates the effect of CA on production or climate resilience, and what evidence exists is hampered by selection bias. Using panel data from Zimbabwe, we test how CA performs during extreme rainfall events - both shortfalls and surpluses. We control for the endogenous adoption decision and find that use of CA in years of average rainfall results in no yield gains, and in some cases yield loses. However, CA is effective in mitigating the negative impacts of deviations in rainfall. We conclude that the lower yields during normal rainfall seasons may be a proximate factor in low uptake of CA. Policy should focus promotion of CA on these climate resilience benefits.  相似文献   
266.
Ecological restoration is an increasingly important tool for managing and improving highly degraded or altered environments. Faced with a large number of sites or ecosystems to restore, and a diverse array of restoration approaches, investments in ecological restoration must be prioritized. Nevertheless, there are relatively few examples of the systematic prioritization of restoration actions. The development of a general theory for ecological restoration that is sufficiently sophisticated and robust to account for the inherent complexity of restoration planning, and yet is flexible and adaptable to ensure applicability to a diverse array of restoration problems is needed. In this paper we draw on principles from systematic conservation planning to explicitly formulate the ‘restoration prioritization problem’. We develop a generalized theory for static and dynamic restoration planning problems, and illustrate how the basic problem formulation can be expanded to allow for many factors characteristic of restoration problems, including spatial dependencies, the possibility of restoration failure, and the choice of multiple restoration techniques. We illustrate the applicability of our generic problem definition by applying it to a case study - restoration prioritization on The Irvine Ranch Natural Landmark in Southern California. Through this case study we illustrate how the definition of the general restoration problem can be extended to account for the specific constraints and considerations of an on-the-ground restoration problem.  相似文献   
267.
The small playa-lakes and other saline wetlands of Monegros, scattered over a dry area with winter cereal monoculture, are threatened by the settlement of new irrigation districts and other kinds of human pressure. Enforcing the protection rules of European Union in these valuable habitats requires, first, their delimitation and monitoring. This article shows how these tasks can be undertaken using remote sensing in conjunction with field observations. A series of Landsat images covering different seasons provided a comprehensive view of these wetlands encompassing their changing facies, hydrologic regime, state of conservation, and functional status. Remotely-sensed data were the primary, and in most cases the only available, source of consistent information. Our approach can help planning and surveying for the implementation of saline wetland protection measures in harmony with the conterminous agricultural areas.  相似文献   
268.
Protected areas present a global heritage. Assessing conservation achievements in protected areas is of crucial importance with respect to the on-time delivery of international biodiversity conservation targets. However, monitoring data from publicly accessible databases for comparative studies of conservation achievements in the protected areas of the world are very scarce, if not non-existent. At first glance this is surprising because, with regards to protected areas, at least according to well established protected area management guidelines and widely accepted public mandates, a great deal of monitoring work and data gathering is to be conducted. This would imply that data on changes of biodiversity in protected areas could be expected to exist, and the constant progress in information technologies and Web tools engenders hope that some of it might even be available online for the global public. This review article presents the results of an extensive online search and review of existing monitoring data from freely accessible online databases for its use in an assessment of conservation achievements in a larger sample of protected areas. Results show two contrary sides to the status quo of accessible data from the World Wide Web for conservation science: data overkill and data scarcity with poor metadata provision. While ever more research is, in fact, based on open-access online data, such as extrapolations of species ranges used in conservation management and planning, it remains almost impossible to obtain a basic set of information for an assessment of conservation achievements within a larger number of protected areas. This awareness has triggered a detailed discussion about the discrepancies in sharing data at the level of protected areas; mismatching relationships between expected activities in protected areas and the capacity for delivering these requirements are certainly among the main challenges. In addition, the fear of data misuse potentially resulting in harm for nature, careers, and competencies still seems to be a critical barrier strictly controlling the willingness to share data. Various initiatives aimed at tackling technical and cultural obstacles are introduced and discussed to reach the goal of a modern resource management based on adaptive management using digital opportunities of the new millennium for a sustainable global village.  相似文献   
269.
The effectiveness of different conservation policies is debated, but the policies are rarely evaluated quantitatively. A voluntary or 'soft' policy based mainly on education provides information about ecosystems and effects of land use, to encourage conservation action. Swedish forestry relies mainly on soft policy, with substantial resources for education and advice to more than 200,000 forest owners, while legal regulation is weak. Increased retention of broadleaved trees at clear-cutting, with environmental benefits in the conifer-dominated forestry, is important in the policy. We used the Swedish National Forest Inventory to analyse this policy for young forests in southern Sweden. Between 1983-1987 and 1998-2002 the policy had no positive effect on saplings (1.3m tall to 4.9 cm dbh) of birch, oak, beech and other species that mostly decreased in density, due to planting of conifers and browsing by ungulates. However, broadleaved conservation trees (>or=15 cm dbh) increased in density, e.g. to about one oak and six birches per ha in young coniferous forest in 1998-2002. The relative increase in density was higher for large (>or=20 cm dbh) than for small trees (15-20 cm dbh). The density of conservation trees was higher on forestland of high than of low productivity. Thus, the soft conservation policy did not influence regeneration of saplings in this type of forestry system, but large broadleaved trees were increasingly saved at 'clear-cuttings'. Advice and educational programmes probably contributed to this result. A continued increase in conservation trees at harvest may require economical support to forest owners.  相似文献   
270.
The River Hayle in south-west England is impacted with metals and can be divided into three regions depending on the copper and zinc concentrations: a low-metal upper section; a highly-contaminated middle section and a moderately contaminated lower section. Hayle river water is toxic to metal-naive brown trout, but brown trout are found in the upper and lower regions. The study aimed to evaluate the population genetic structure of River Hayle brown trout and to determine if the highly-contaminated section acts as a chemical barrier to migration. Population genetic analysis indicated that metals were not a barrier to gene flow within the river, but there was a high level of differentiation observed between fish sampled at two sites in the upper region, despite being separated by only 1 km. The metal tolerance trait exhibited by this brown trout population may represent an important component of the species genetic diversity in this region.  相似文献   
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