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41.
A review of the use of planning and design briefs by local authorities in the United Kingdom was carried out in 1982–83 to test whether the role of the brief as an instrument of local policy and as a promotional tool in the development process was being fully exploited. The paper provides a state of the art review, presents a summary of the findings and offers some comments on the results. It concludes that most authorities now use briefs as part of their normal planning procedures, but that there is potential which is not yet being exploited.  相似文献   
42.
根据我国宪法和地方组织法等的规定,对地方环境立法中的若干关系问题,从理论和实践的结合上作了探讨。  相似文献   
43.
We review the basic mathematical concepts of random walk particle tracking (RWPT) and its advantages and limitations. Three different numerical approaches to overcome the local mass conservation problem of the random walk methodology are examined: (i) the interpolation method, (ii) the reflection principle, and (iii) the generalized stochastic differential equations (GSDE). Analytical solutions of the spatial moments for a two-layer system are compared to model predictions using the different techniques and results demonstrate that the interpolation method reproduces correctly average velocity, but fails to reproduce macrodispersion at higher hydraulic conductivity contrasts between the two layers. On the contrary, the reflection principle and the GSDE approach underestimate average velocity, but reproduce macrodispersion better for high contrasts. The different behavior is based on an artificial shift of mass for increasing heterogeneities for the GSDE approach and the reflection principle, whereas the interpolation method suffers from the smoothing of the dispersion tensor. The behavior of these approaches was furthermore analyzed in two-dimensional heterogeneous hydraulic conductivity fields, which are characterized by different random function models. Solute transport was simulated correctly by all three approaches for the reference fields having Gaussian structures or non-Gaussian structures with an isotropic spatial correlation, even for a variance of the natural log of hydraulic conductivity of sigma(lnK)(2)=4. However, for the non-Gaussian model with a strong anisotropic spatial correlation and a variance of sigma(lnK)(2)=2 and higher, the interpolation method was the only technique modelling solute transport correctly. Furthermore, we discuss the general applicability of random walk particle tracking in comparison to the standard transport models and conclude that in advection-dominated problems using a high spatial discretization or requiring the performance of many model runs, RWPT represents a good alternative for modelling contaminant transport.  相似文献   
44.
山地林火特征与扑救的若干问题   总被引:5,自引:2,他引:3  
根据火灾科学、流体力学、气象学和地理科学中的一些基本理论以及实际火场经验,分析了山地条件下:(1)坡度对火行为的直接影响;(2)简单地形中局地风特征和火行为特征;(3)典型山地地形—流系地形中的局地风和林火行为特征,提出了扑救山地林火应注意的若干问题  相似文献   
45.
Global greenhouse gas emissions from air travel (GHG-A) are on the rise, and projections point towards a rapid growth in the coming decades. This study aims to examine how local government (cities), addresses GHG-A in their Sustainable Energy Action Plans (SEAP). To fulfil this aim, over 200 SEAPs were analysed focusing on three issues: (1) Treatment of GHG-A in local emissions inventories; (2) Policy initiatives within this domain; and (3) The cities’ perceptions of the conflicts of interests. Results showed that more than half of the cities acknowledge the challenge of GHG-A, around one third include GHG-A in their emissions inventories, and more than one quarter have initiated policy interventions. To categorise these interventions, we have added a mode ‘governing by agenda setting’ to an existing analytical framework, ‘Modes of governing’. With their authority limited to the local setting, this mode of governing is a common channel for cities to push changes at higher levels.  相似文献   
46.
乌鲁木齐市市民环境意识万人问卷调查报告   总被引:3,自引:0,他引:3  
为贯彻全国和自治区第4次环保会议精神,了解和提高全市各族群众的环境意识,使环境保护基本国策深入人心,乌鲁木齐市环保局在1998年“六·五”世界环境日之际开展了以“关心环境保护,共建美丽首府”为主题的市民环境意识万人问卷活动。由全市7区1县及2个开发区环保局(站)协助,分别在政府机关、厂矿、学校、街头、摊点进行发放问卷活动。调查结果初步摸清了乌鲁木齐市在环境宣传教育中所取得的成效和存在的问题,为今后更好地加强环境宣传教育,普及环境科学知识,提高社会各界环境意识提供了参考信息。  相似文献   
47.
Patterns of sex ratio variation and maternal investment reported in the literature are often inconsistent. This could be due to intra- and inter-specific variation in social systems, but may also be a result of the a posteriori nature of much of this type of analysis or the testing of models which are inappropriate. Two recent papers reported directly opposed results concerning variation in offspring sex ratios in relation to maternal condition in roe deer, interpreting the results as support for the Trivers and Willard model and for the local resource competition hypothesis, respectively. In this paper, we present data on offspring sex ratios and early juvenile body weight from two long-term studies of this species to test predictions arising from these two models concerning sex biases in litter composition and maternal care. First, we observed no consistent pattern of sex differences in an index of weaning weight or body weight at 1 month old in either population, indicating a lack of sex bias in maternal care. However, in one population, higher maternal body weight was associated with higher juvenile body weight of daughters, but not of sons. Secondly, we found a negative, but not statistically significant, relationship between maternal body weight and litter sex ratio such that heavier females tended to produce more daughters and lighter females to produce more sons. These results indicate that roe females which have additional investment potential available do not invest it in sons, as predicted by the Trivers and Willard model. Our results may provide some support that roe deer are subject to local resource competition acting at the level of the individual mother; however, the fact that particular trends in sex ratio data can be explained in functional terms provides no indication that they are actually adaptive. Received: 9 December 1997 / Accepted after revision: 11 November 1998  相似文献   
48.
云南省土著民族在长期生产实践中积累了丰富的知识,形成了特有的习俗。这些知识和习俗对保护当地生态环境和资源发挥了重大作用。本文从宗教信仰、民俗、耕作制度、栽培、选种等方面进行归纳,以期从中汲取有益于农业持续发展的精华。  相似文献   
49.
This paper presents the results of research conducted between 2009 and 2014 in the village of Khanda Sharol in the state of Rajasthan, India. Our research objective was to determine how the livelihoods of village residents have been affected by the intensification of forest use, and the resulting loss of domestic access to traditionally used forest resources. Results indicate that changes in forest cover have resulted in a loss of livelihood options for village residents. Yet rather than being victimized by environmental change processes, this paper shows how villagers have responded by partnering with public and private actors to develop a community protected forest area that is now helping villagers to meet their livelihood needs. These findings suggest that sustainable livelihoods in rural regions of India require committed and scaled approaches involving local, public, and private actors.  相似文献   
50.
Florida is one of the largest spenders on the environment in the U.S. Employing a database from Florida counties, this study examines two distinct environmental funding areas in government: funding to protect the environment, and funding to develop the environment. These two types of funding serve different purposes, support different activities and operations, and draw from different revenue sources. The results show that environmental funding in government is a response to the environmental pressure generated by economic activities and population growth. Counties with a higher level of manufacturing and farming activity spend more to protect the environment, while counties with higher population densities spend more to develop the environment. Moreover, counties with more funding for public safety and economic development activities spend less on the environment, indicating that environmental funding is influenced by the political processes in public budgeting in which diversified interests compete for resources. These results show that environmental spending in government is the result of combined forces arising from environmental pressure and budgetary politics.  相似文献   
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