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281.
The views expressed here are the author's and do not necessarily reflect an expression of opinion on the part of the United Nations. The objective of sustainable development is to integrate environmental concerns with mainstream socio-economic policies. Integrated policies need to be supported by integrated data. Environmental accounting achieves this integration by incorporating environmental costs and benefits into conventional national accounts. Modified accounting aggregates can thus be used in defining and measuring environmentally sound and sustainable economic growth. Further development objectives need to be assessed by more comprehensive, though necessarily less integrative, systems of environment statistics and indicators. Integrative frameworks for the different statistical systems in the fields of economy, environment and population would facilitate the provision of comparable data for the analysis of integrated development.  相似文献   
282.
This paper argues that in Kenya, environmental and economic factors will favour the continued use of biomass as a primary fuel for household and institutional cooking for the next decade or longer. The paper describes several successful projects which have improved the efficiency of urban charcoal use and of rural woodfuel use. The Kenya Ceramic Jiko, a more efficient version of the traditional charcoal stove, is a model programme sustained by free market competition, artisans participation, and widespread public acceptance. The Maendeleo stove is the best example of a successful rural woodstove project. The performance attributes of the stove, and its promotion through Kenya's largest women's organization, have resulted in the distribution of an estimated 26 000 Maendeleo stoves. Rural stove efficiency will become important as the cash-based economy expands in those areas. Agroforestry will also be critical to an enhanced use of biomass energy in Kenya. Experience to date shows that successful agroforestry programmes will have to be appropriate to local conditions and crops .  相似文献   
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284.
ABSTRACT. The ability to replicate storms on a rainfall simulator over an iconic watershed model permits the study of the effectiveness of dams of different sizes and locations in reducing flood peaks. This study empirically confirms that, when storms uniformly and completely cover the watershed, large dams are nearly twice as effective as a network of small and medium dams in reducing the flood.  相似文献   
285.
Three fundamental concepts linking drainage basin characteristics, stream behavior, and management of watersheds are deduced from field data and observations. An electrical analogy of a watershed clarifies definitions and broadens understanding of this complex natural resource. The three basic principles deal with (1) the interrelationships of watershed morphology, constitution, and appearance; (2) the nature of the control man can exert over runoff-influencing forces, and (3) the efficiency of watershed management efforts. Recognition of these principles can assist educators, managers, planners and researchers to more fully inform students and to more effectively guide and evaluate management decisions.  相似文献   
286.
A 30-year record of monthly precipitation for Northern New Jersey was analyzed for its statistical components. With a weak annual periodicity eliminated, the series was found to be random. The data for each month were fit with a gamma distribution using Thom's suggested best estimates of the distribution parameters. A one-thousand-year simulated monthly precipitation series was generated using random values from the twelve gamma distributions. The statistical properties of the simulated and sample time series agreed well. Numerous anomalous precipitation regimes were observed in the simulated data.  相似文献   
287.
Moths learn to associate a flower odor with a food reward after a few learning trials. Can a hungry, male moth learn to associate a sex attractant with food instead of with sex? We provided a hungry male with odors of single female sex pheromone components, of the full sex pheromone blend or of a flower odor component as cues in an appetitive learning assay. The male learned the single pheromone components just as well as the flower odor. Learning was, however, severely impaired when the full sex pheromone blend was used as conditioning stimulus. The "hard-wiring" between pheromone odor and sex thus seems to be restricted to those circumstances when the male moth experiences the full blend.  相似文献   
288.
Prompted by the calls in recent years to link relief practice to peace-building, development, or both, several conferences and papers have recently mounted a strong critique, seeing these 'broadenings' of relief as 'eroding' or 'corrupting' core humanitarian principles and playing into neo-isolationist agendas to slash humanitarianism. This paper argues that whereas these critiques have important goals in mind when they encourage a concentration on the basics of relief, there has been a loss of subtlety in the ensuing debate. Considering each element of the debate in turn, the paper argues that there is more common ground between 'new' and 'old', 'broadened' and 'basics' relief than at first appears. In concluding, it is argued that further research on key questions, and an openness to hear all perspectives will get us further than entrenched positions and rallying cries.  相似文献   
289.
ABSTRACT

City strategic plans and enabling policies provide a framework for and inform future development across multiple scales. An exemplar city strategic plan will be one based on evidence, enabled by complementary policy outcomes, and built on the knowledge of the existing landscape. This study evaluated the plan quality of eighteen metropolitan strategic plans for city members in the 100 Resilient Cities initiative. A protocol was developed containing thirty-two indicators to assess plans capacity to act as a strategic planning tool to develop, analyse and implement strategies for the Urban Heat Island (UHI) and climate change mitigation and adaptation. The evaluation indicated that strategies addressing the UHI are rarely included in metropolitan plans. Strategic plans showed a lack of evidence-base to inform the potential actions. Urban warming is often linked to extreme weather events anticipated under climate change, not the UHI as a systemic and increasing phenomenon. We recommend that the pathway to addressing UHI mitigation and adaptation may lie in its nexus to aspects of climate change that concurrently can serve to support liveable and resilient cities.  相似文献   
290.
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