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441.
Drivers of agricultural sustainability in developing countries: a review   总被引:1,自引:0,他引:1  
Agricultural development has been an effective instrument for poverty alleviation and economic development in developing countries over the latter half of the twentieth century, and over 80 % of rural people globally still depend on agriculture for their living. However, issues such as water availability, land degradation and an increasing dependence on chemical fertilisers and pesticides continue to be on-going threats to sustainable agricultural development. These threats are being driven by the pressing need to ensure food security in the face of rapidly growing and urbanising populations. Developing countries will therefore continue to need improved methods for planning sustainable agricultural development. This paper presents a review of agricultural sustainability assessment in developing countries. The review highlights some of the key weaknesses that persist in sustainability assessment and the need to consider not only indicators of sustainability but also the drivers that influence indicator behaviour. We argue that without a good understanding of the drivers of sustainability and their systemic relationships to indicators, sustainability assessments run the risk of focusing on symptoms without addressing underlying causes of adverse indicator trends. Drivers of agricultural sustainability in developing countries encompass a range of demographic, natural, socio-economic, political, institutional and management factors. Understanding these and their relationships to sustainability indicators is needed in order to develop agricultural development policy that supports sustainability. The paper presents a conceptual framework for guiding systemic agricultural sustainability assessment and agricultural development planning in developing countries that includes both sustainability indicators and drives, and considers the broad relationships between them.  相似文献   
442.
The promotion of development projects based on the commercialization of non‐timber forest products has increased in recent decades, showing a positive contribution to rural development; yet it has led to controversial approaches in resource preservation. This paper examines the case of Candelilla wax from the Chihuahuan Desert in northern Mexico, identifying its potential contribution to poverty alleviation in marginal areas, and its unique opportunity to access potential markets of a wide variety of industries all around the world. In this paper, the authors base their analysis on three main aspects: social, economic and environmental. Potential benefits that could be obtained from the collaboration of private institutions, development organizations, policymakers and rural producers through integrated rural development projects are featured.  相似文献   
443.
Applying Higgins' regulatory focus theory, we hypothesized that the effect of positive/negative feedback on motivation and performance is moderated by task type, which is argued to be an antecedent to situational regulatory focus (promotion or prevention). Thus, first we demonstrated that some tasks (e.g., tasks requiring creativity) are perceived as promotion tasks, whereas others (e.g., those requiring vigilance and attention to detail) are perceived as prevention tasks. Second, as expected, our tests in two studies of the moderation hypothesis showed that positive feedback increased self‐reported motivation (meta‐analysis across samples: N = 315, d = 0.43) and actual performance (N = 55, d = 0.67) among people working on promotion tasks, relative to negative feedback. Positive feedback, however, decreased motivation (N = 318, d = ?0.33) and performance (N = 55, d = ?0.37) among individuals working on prevention tasks, relative to negative feedback. These findings suggest that (a) performance of different tasks can affect regulatory focus and (b) variability in positive/negative feedback effects can be partially explained by regulatory focus and task type. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
444.
There is a growing interest among scholars in instruments based on environmental worldview. Several studies have used instruments of this kind to compare groups of children or to assess the impact of environmental education initiatives (EEIs) on children’s environmental worldview. When using scales of this nature, it is important to control for factors that might blur the true impact of EEIs. One such factor - and which may have been neglected - is personality. This study (n = 957) examines the link between environmental worldview of Belgian adolescents (as measured by the New Environmental Paradigm scale for children - NEP) and their personality (as measured by the Hierarchical Personality Inventory for Children - HiPIC). The results show that adolescents who are willing to take responsibility for their actions and who feel in control over the outcomes of their decisions are more likely to have an ecocentric worldview. Furthermore, this study demonstrates that, for Belgian adolescents, egocentrism and ecocentrism are opposite conceptions. All correlations were, however, small and showed no deterministic pattern in the relationship between adolescents’ environmental worldview and personality, indicating that worldviews are not stable or innate characteristics within individuals, but can be influenced by interactions between the individual and its context. Personality traits explained only a very small part of the variation in adolescents’ environmental worldview (.7%), suggesting that they are unlikely to blur the impact of EEIs in worldview-based assessment. This is an important finding as it indicates that the results of studies showing differences in the environmental worldview of different groups of respondents or changes in their environmental worldview as a result of taking part in an EEI are not artefacts of non-control for personality and that they may, therefore, reflect genuine differences, changes or impacts.  相似文献   
445.
Armitage KB  Van Vuren DH  Ozgul A  Oli MK 《Ecology》2011,92(1):218-227
We investigated factors influencing natal dispersal in 231 female yearling yellow-bellied marmots (Marmota flaviventris) using comprehensive analysis of 10 years (1983-1993) of radiotelemetry and 37 years (1963-1999) of capture-mark-recapture data. Only individuals whose dispersal status was verified, primarily by radiotelemetry, were considered. Univariate analyses revealed that six of the 24 variables we studied significantly influenced dispersal: dispersal was less likely when the mother was present, amicable behavior with the mother and play behavior were more frequent, and spatial overlap was greater with the mother, with matriline females, and with other yearling females. Using both univariate and multivariate analyses, we tested several hypotheses proposed as proximate causes of dispersal. We rejected inbreeding avoidance, population density, body size, social intolerance, and kin competition as factors influencing dispersal. Instead, our results indicate that kin cooperation, expressed via cohesive behaviors and with a focus on the mother, influenced dispersal by promoting philopatry. Kin cooperation may be an underappreciated factor influencing dispersal in both social and nonsocial species.  相似文献   
446.
The WTO leaves discretion over environmental policies to its members, but requests that a fundamental non-discrimination principle is respected: National Treatment (NT). The provision seeks to prevent protectionist use of domestic policy instruments, requesting that when an imported product is sufficiently similar to a domestic product, they are treated identically. WTO adjudicators will often face severe informational problems in environmental disputes. Important for the practical implementation of NT is therefore the allocation of the burden of proof (BoP). This paper highlights basic implications of the BoP for the occurrence of judicial errors, for the environment and for welfare, using a setting where NT serves its intended role of supporting negotiated tariff liberalization. The paper suggests that NT may indeed constrain environmental policies, but that this may be desirable from an efficiency point of view. Also, BoP rules that benefit the environment may not benefit global welfare, and conversely.  相似文献   
447.
Cypress needles collected at the edge of the Malvési uranium facility (SW France) exhibit enhanced activities of actinides and some decay products (uranium, americium, plutonium, (230)Th, (226)Ra) compared to a remote site. These enhanced activities resulted from the release of U via smokestacks and passive release from former artificial ponds located inside the nuclear site. Enhanced activities are also observed in selected produce (wheat, lettuce, fruits) sampled from the edge of the site. However, excess actinides measured in wheat grains in 2007 are inconsistent with the activities and the uranium ratio measured in the soils. This result suggests that the studied annual crops were contaminated mainly through the short-term release of airborne actinides, and that other transfer pathways, such as, uptake through the roots or adhesion of soil particles, were negligible.  相似文献   
448.
Small-holder farmers in Ethiopia are facing several climate related hazards, in particular highly variable rainfall with severe droughts which can have devastating effects on their livelihoods. Projected changes in climate are expected to aggravate the existing challenges. This study examines farmer perceptions on current climate variability and long-term changes, current adaptive strategies, and potential barriers for successful further adaptation in two case study regions—the Central Rift Valley (CRV) and Kobo Valley. The study was based on a household questionnaire, interviews with key stakeholders, and focus group discussions. The result revealed that about 99 % of the respondents at the CRV and 96 % at the Kobo Valley perceived an increase in temperature and 94 % at CRV and 91 % at the Kobo Valley perceived a decrease in rainfall over the last 20–30 years. Inter-annual and intraseasonal rainfall variability also has increased according to the farmers. The observed climate data (1977–2009) also showed an increasing trend in temperature and high inter-annual and intra-seasonal rainfall variability. In contrast to farmers’ perceptions of a decrease in rainfall totals, observed rainfall data showed no statistically significant decline. The interaction among various bio-physical and socio-economic factors, changes in rainfall intensity and reduced water available to crops due to increased hot spells, may have influenced the perception of farmers with respect to rainfall trends. In recent decades, farmers in both the CRV and Kobo have changed farming practices to adapt to perceived climate change and variability, for example, through crop and variety choice, adjustment of cropping calendar, and in situ moisture conservation. These relatively low-cost changes in farm practices were within the limited adaptation capacity of farmers, which may be insufficient to deal with the impacts of future climate change. Anticipated climate change is expected to impose new risks outside the range of current experiences. To enable farmers to adapt to these impacts critical technological, institutional, and market-access constraints need to be removed. Inconsistencies between farmers’ perceptions and observed climate trends (e.g., decrease in annual rainfall) could lead to sub-optimal or counterproductive adaptations, and therefore must be removed by better communication and capacity building, for example through Climate Field Schools. Enabling strategies, which are among others targeted at agricultural inputs, credit supply, market access, and strengthening of local knowledge and information services need to become integral part of government policies to assist farmers to adapt to the impacts of current and future climate change.  相似文献   
449.
Not much is known about lay public perceptions of non-native species and their underlying values. Public awareness and engagement, however, are important aspects in invasive species management. In this study, we examined the relations between the lay public’s visions of nature, their knowledge about non-native species, and their perceptions of non-native species and invasive species management with a survey administered in the Netherlands. Within this framework, we identified three measures for perception of non-native species: perceived risk, control and engagement. In general, respondents scored moderate values for perceived risk and personal engagement. However, in case of potential ecological or human health risks, control measures were supported. Respondents’ images of the human–nature relationship proved to be relevant in engagement in problems caused by invasive species and in recognizing the need for control, while images of nature appeared to be most important in perceiving risks to the environment. We also found that eradication of non-native species was predominantly opposed for species with a high cuddliness factor such as mammals and bird species. We conclude that lay public perceptions of non-native species have to be put in a wider context of visions of nature, and we discuss the implications for public support for invasive species management.  相似文献   
450.
Since 1994, more than 2000 European local governments have adopted the principles of the Aalborg Charter as a basis for local sustainability action. Now, ten years later in June 2004, these local governments will gather once again in Aalborg, Denmark at the Fourth European Conference on Sustainable Cities and Towns in Europe, Inspiring Futures—Aalborg+10. The Aalborg+10 event will celebrate a decade of European local sustainability action, evaluate progress and stagnation, and, more importantly, will adopt new commitments to move from Agenda to Action. The conference will be crucial for accelerating local sustainability in Europe and to move towards Local Action. Here an overview is provided on the context against which this important conference is set and its expected outcomes.  相似文献   
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