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171.
A method is described for the rapid survey and determination of the ecological value of woodlots. The three dominant tree species in a stand are given a visual ranking that is converted to awoodlot index through the use of species adaptation values. The woodlot index is scaled by presettlement vegetation type to yield awoodlot scale. The ecologically most valuable woodlots in a region are identified by using the woodlot scale and data on woodlot area, human disturbance, and tree density. The woodlot index corresponds closely to results from conventional methods of woodlot surveys. This method should be valuable to land-use planners for environmental impact assessment and regional planning.  相似文献   
172.
A central government Consultation Paper issued in 1984 argues the case for simplified planning zones. These are seen to offer greater speed and certainty to developers and are closely related to the Enterprise Zone concept. This paper examines the context to the proposal, reviews the details of the Consultation Paper, and identifies the nature of the response to the idea.  相似文献   
173.
The New Cities of Egypt represent a major effort to redistribute investment and population away from Cairo and the Delta in a brave attempt to use desert land. Through a study of three cities under construction, the reliance on government‐built walk‐up flats for housing provision is discussed and its relevance for later phases questioned. In conclusion, the efficacy of the New Cities as counter‐attractions is doubted in the absence of effective controls on the growth of Cairo.  相似文献   
174.
Levees and floodwalls are used extensively throughout the United States for flood control. Levee projects often lack ecological, recreational, and aesthetic values, except for incidental fish and wildlife benefits derived from borrow pits and recreational facilities found in some urban settings. In recent years increased environmental concern within construction agencies and greater responsiveness to public opinion have resulted in increasing numbers of levee projects designed, built, and maintained with environmental objectives in mind. This paper reviews environmental concepts successfully employed on levee projects constructed in recent years by the US Army Corps of Engineers. Some of the most innovative concepts are described and illustrated and design considerations are discussed.  相似文献   
175.
Integrated resource management (IRM) is currently implemented in many parts of the world. This article promotes a pragmatic interpretation and suggests that idealistic beliefs in the problem-solving capacities of IRM are not justified. Successful implementation and performance of IRM are primarily a function of the historical context into which a project is placed. A comparative analysis of several case studies in Western Canada provides evidence for this argument, and the results can be summarized in a conceptual model about integration in resource management. IRM is interpreted as a process of constructing an objective reality of integration for sectorial management decisions, and this construction involves the transformations of power structures. This article suggests several pragmatic conclusions for IRM practice.  相似文献   
176.
This paper analyses the currents which gave rise to the 1947 Town & Country Planning Act. It describes the main statutory events in the first half of the 20th century and considers the progress made in implementing the legislation. It is argued that, while the 1947 Act was a major advance on what went before, it is not a significant departure.  相似文献   
177.
The paper examines characteristics of science parks in the face of employment decline, raising doubts about the scale of their success. The paper re‐examines previous research on the existence and causes of long waves of economic growth and decline and concludes that if these are not generated by innovations in production, then it should not be surprising that science parks have not lived up to expectations.  相似文献   
178.
The historical and regional context to the development of a planning strategy for Barcelona is examined, providing an explanation of the obstacles to development of new towns in the region, and that of Riera de Caldes in particular. The paper analyses the reasons for the failure to develop the new town, and its subsequent reversion to rural uses and a place of pilgrimage for environmentalists.  相似文献   
179.
The computer and telecommunications technology has created new opportunities for developing interaction between offices and enterprises located far away from each other. Even if the market forces favour concentration to R & D centres in the big cities and in university towns, there are expectations that the distance over‐bridging qualities of the new technology can create development opportunities for sparsely populated peripheral areas. In this paper the interplay between the new technology and other important factors in the local and regional environment are discussed with the focus on both opportunities and restrictions.  相似文献   
180.
ABSTRACT: Water resource scientists face complex tasks in evaluating aspects of water projects, but relatively few assessment procedures have been applied and accepted as standard applications. Decision-makers often rely on environmental assessments to evaluate the value and operation of projects. There is often confusion about scientists' role in policy decisions. The scientist can affect policy-making as an expert withess, an advocate or a surrogate. By understanding the policy process, scientists can make their work more “policy relevant.” Using the Terror Lake hydro project in Alaska as a guide, three lessons are discussed: (1) not all problems are able to be solved with technology; (2) policy-relevant technology is rarely imposed on a problem; and (3) the scientist need not just react to the policy process, but can have an impact on how that process unfolds.  相似文献   
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