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111.
The resource curse 总被引:7,自引:0,他引:7
Countries that possess rich mineral deposits, it is widely assumed, are fortunate. Such deposits are assets, part of a country's natural capital. Mining is the key that converts dormant mineral wealth into schools, homes, ports, and other forms of capital that directly contribute to economic development. Over the past two decades, however, a more negative view of mining has emerged that questions the positive relationship between mineral extraction and economic development. The impetus for the alternative view came from empirical studies suggesting that countries where mining is important have not grown as rapidly as other countries. More recent studies have explored the possible reasons behind the disappointing performance of many mineral producing countries. While the central point of contention between the conventional and alternative views — namely, whether or not mining usually promotes economic development — remains unresolved, there is widespread agreement that rich mineral deposits provide developing countries with opportunities, which in some instances have been used wisely to promote development, and in other instances have been misused, hurting development. The consensus on this issue is important, for it means that one uniform policy toward all mining in the developing world is not desirable, despite the recent suggestions by some to the contrary. The appropriate public policy question is not should we or should we not promote mining in the developing countries, but rather where should we encourage it and how can we ensure that it contributes as much as possible to economic development and poverty alleviation. 相似文献
112.
R. J. Portier D. L. Sattler D. G. Hoover T. M. Davis S. E. Williams 《补救:环境净化治理成本、技术与工艺杂志》1998,8(4):95-105
Well-recovery networks coupled to immobilized microbe bioreactors (IMBRs) were installed at a 172-acre former wood preserving facility for the bioremediation of organic wood preservatives present in site groundwater. Free-phase creosote from the hardpan and soluble preservative fractions contained in subsurface groundwater were pumped separately to different holding tanks. Trace creosote fractions contained in the subsurface groundwater were further gravity separated in the holding tank. Immobilized microbial isolates evaluated in earlier laboratory and field pilot tests were established into two 40, 000-liter bioreactors for the biodegradation of all targeted consitituents. Microbial growth, dissolved oxygen, pH, nutrients, flow rate, and temperature were monitored in this in situ/ex situ bioremediation system. The process was used to remove the polycyclic aromatic hydrocarbon (PAH) and phenolic components of creosote and pentachlorophenol from contaminated groundwater. Data generated during the past 2 1/2 years indicate that 26 target compounds consistently are reduced to levels acceptable for discharge. Currently operating in Baldwin, Florida, this full-scale prototype is remediating the former wood preserving facility and is being used as a model system for the design and construction of new bioreactor systems needed at similar industrial sites in the United States and abroad. 相似文献
113.
David L. Rick John W. Davis Shari L. Kram Michael N. Mang Tim D. Lickly 《Journal of Polymers and the Environment》1998,6(3):143-157
An epoxy-based thermoplastic polyester, poly(hydroxy ester ether), was incubated under aerobic conditions in a laboratory-scale compost system for 168 days to evaluate its potential for biodegradation. Radiolabeled test polymer [uniformly 14C ring-labeled, poly(hydroxy ester ether)] was incorporated into a mature compost and a sludge-amended compost at a loading of 3 mg test polymer/g compost. 14C-Cellulose was used as the positive control and a biologically inhibited control reactor was used to assess abiotic degradation of the test polymer. Degradation of the test polymer was assessed by measuring the amount of 14C-CO2 from each of the test reactors. In addition, at selected time intervals subsamples of the compost were collected and serially extracted with water, methanol, and dimethylformamide to monitor degradation of the 14C-test polymer and provide a partial characterization of the degradation intermediates. Extensive degradation of 14C-poly(hydroxy ester ether) was observed in the test reactors with degradation half-life of the parent polymer (t
1/2) of approximately 32 days. By the end of the study, only 2% of the total 14C activity in the test reactors was attributed to intact polymer, with most of the measurable 14C activity converted to either 14C-CO2 (26% of total 14C activity) or nonextractable products (accounting for 60% of the total activity). In contrast to the test reactors, only 3% of the 14C-poly(hydroxy ester ether) added to the biologically inhibited control reactor was mineralized to 14C-CO2. The results obtained from the microbially active and biologically inhibited compost systems indicate that the poly(hydroxy ester ether) polymer was degraded, at least in part, by a biologically mediated process. 相似文献
114.
Ray Jay Davis George William Sherk Donald Phelps 《Journal of the American Water Resources Association》1995,31(4):583-588
ABSTRACT: Whomever would affect water policy development must influence the water legislative process. This paper discusses in the context of the Model State Water Allocation Code the following ten ideas about doing that: (1) seek the right timing for enactment; (2) set modest goals; (3) prepare a well-drafted proposal; (4) recognize diversity by offering legislative choices; (5) consider the impacts of adoption; (6) make alliances; (7) respect executive influence; (8) become involved in legislative interaction; (9) be flexible; and (10) persist. Heeding these ideas, although not guaranteeing enactment, is sure to be educational for participants and useful to legislators. 相似文献
115.
This research considers the question of changing environmental values within the leadership of firms responsible for the management of pollution as an unwanted byproduct. Information was obtained from a pair of surveys mailed to the chief executive officers (CEOs) of the 50 largest firms listed within the mining and manufacturing directories of Colorado, Montana, Utah, and Wyoming in 1976 and again in 1986. The authors found that industry CEOs were more supportive of environmental concerns in 1986 than 1976, suggesting that ecological values have become institutionalized to some extent. Yet, there is little indication that this attitudinal shift in environmental concern among CEOs has been accompanied by a willingness to spend a larger proportion of the company budget on pollution control or to improve working relationships with federal regulatory officials. 相似文献
116.
A process is described for making comparative valuations of a wide range of environmental management activities when the combined social, economic, managerial, and political benefits of some (but not all) of these activities cannot be adequately described in economic terms and when budgetary constraints do not permit funding of all activities under consideration. The process accounts for subjective judgment and contains a formal rigorous decision strategy that takes the place of intuition when quantitative and qualitative values of environmental activities need to be evaluated. 相似文献
117.
Recent legislation mandates an increased role for public participation in natural resource policy making. This paper presents an operational way to provide those impacted with relevant information and to enable public officials to assess public reaction to proposed policies. The methodology transforms results obtained from a multisector model of income formation and distribution into positive economic measures of distributional impacts. The usefulness of the methodology is illustrated in the context of a policy to increase coal surface mining on public lands. 相似文献
118.
Joel Michaelsen Laura Haston Frank W. Davis 《Journal of the American Water Resources Association》1987,23(5):809-818
ABSTRACT: Coastal central California is a region that has never been the subject of tree-ring studies. New tree-ring chronologies developed from cores of big cone spruce (Pseudotusuga macrocarpa (Torr.) Mayr.) growing in the Transverse Ranges of central Santa Barbara county were used to reconstruct precipitation fluctuations for this region. To verify the new reconstructions, calibration with recorded rainfall using cross-validation, comparison with other reconstructions, and documentary evidence from historical sources were utilized. The precipitation reconstructions show that there have not been fluctuations in mean precipitation on time scales longer than 30 years, but there have been major fluctuations in precipitation variability including changes in the frequency of extremes and rare events that have not occurred in the modern record. 相似文献
119.
Gary E. Davis 《Environmental monitoring and assessment》1993,26(2-3):99-105
Natural resource managers must know the condition of resources entrusted to their steward-ship so that they can maintain unimpaired resources and know when to restore impaired ecosystems. Resource monitoring programs should be designed to provide indications of ecosystem health, define limits of normal variation, identify abnormal conditions, and suggest potential agents of abnormal changes. Development of a conceptual model that identifies all ecosystem components and their relationships is the first step in the design of such a diagnostic monitoring program. Design studies, with field testing on each selected system component, are required to determine the parameters to be measured and to establish monitoring protocols. The best approach to diagnostic monitoring appears to be based on the population dynamics of selected species relative to physical and chemical environmental factors. Both management and monitoring of natural ecosystems need to be recognized as experimental endeavors, and thus approached in an iterative fashion with the scientific method to reduce uncertainty and cost. 相似文献
120.
Regulatory agencies commonly set standards for a myriad of chemical and physical hazards, with a special focus on carcinogens. This focus can obscure the need to update previously set standards for non-carcinogenic hazards in response to new scientific data. This paper considers n-hexane as a representative chemical hazard: the occupational standard of 500 ppm over an 8 hr time weighted average for a 40 hr week as set in 1948. In the last 12 yr, n-hexane has been shown to cause adverse effects on the peripheral and central nervous systems, the eye, and the respiratory tract. Yet, these new data have not, as yet, been incorporated into a revised standard for n-hexane. The lack of scientific data on the carcinogenicity of n-hexane may be an underlying reason explaining the failure of regulatory agencies to revise their standards. Perhaps, the most troubling problem to regulatory agencies is the sheer magnitude of the chemical regulatory burden. Research should proceed on developing meaningful categories or groupings both for the initial setting of standards and for revising existing standards. 相似文献