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1.
The US EPA published guidelines for the application of ecological risk assessment (ERA) in the USA in 1998 (US EPA 1998). The process diagram derived by Murray and Claassen (1999) in an evaluation of the US EPA framework is discussed in the context of the South African National Water Act. The evaluation discusses the various steps involved in an ERA and how it can be applied in the implementation of the National Water Act. It is concluded that the application of ERA can make a significant contribution towards sustainable water resource management. Two requirements for this are the need for more demonstration projects and that capacity be developed in risk assessment and risk-based decision making.  相似文献   

2.
Human influence is now so pervasive that every ecosystem on Earth is being managed, whether intentionally or inadvertently. It is therefore imperative for scientists and managers to work together so that appropriate management regimes can be put in place wherever possible. However, it is not always clear what is appropriate, and the difficulties that often arise when scientists and managers work together can be even further compounded by the inclusion of lay stakeholders in the decision-making process. The expansion of interdisciplinary undergraduate and graduate programs would help both scientists and managers to deal more effectively with sociological issues and to understand how economic and demographic changes impact on natural resources. In addition, continuing education programs in these areas should be made available to established professionals to help them deal with new challenges. The concept of ecosystem services should be used to communicate the importance of various ecosystem components and processes to a broader audience. Consensus on a management regime can often be achieved through adaptive management. The process by which interdisciplinary collaboration can lead to new insights and research initiatives is exemplified by a resource management study on the island of Kosrae, Federated States of Micronesia. As a paradigm of natural resource management, microcosms like this small island community offer a unique opportunity for training and education. Received 4 October 2000; accepted 20 March 2001.  相似文献   

3.
The precautionary principle, a familiar constituent of international and European environmental law, has only very recently entered the vocabulary of domestic environmental policy debates in the United States. The question naturally arises what role such a principle should play in American law. By breaking down statements of the precautionary principle into distinct ele ments, one can more readily find ways in which U.S. law reflects the precau tionary principle. This analysis reveals that American environmental law con tains precautionary elements and goals in many and varied settings, from the management of natural ecosystems, to pollution control standards, to risk assessment methodology. However, the precautionary approach appears in a highly diluted or compromised form. With rare exceptions, U.S. law balances precaution against other considerations, most importantly cost. Therefore, while precautionary elements are firmly entrenched in U.S. environmental law, it is more accurate to say that it reflects a precautionary preference rather than the precautionary principle.  相似文献   

4.
William Ascher 《Ecosystems》2001,4(8):742-757
To cope with the daunting challenges posed by system complexity while maximizing their organizational interests, resource management institutions must implement strategies aimed at reducing some of the particular dimensions of complexity. Virtually all of the recent initiatives to improve resource management—ecosystem management, adaptive management, stakeholder negotiation, disturbance prevention, multiple mandates for resource management agencies, resource homogenization, restoration ecology, the creation of protected areas, the restoration of local-user rights, and algorithmic resource exploitation rules—are vulnerable to inappropriate interest-driven simplifications, many of which result from patterns of perverse learning. A research agenda designed to identify better means of coping with complexity and the effects of organizational interests could help to improve resource and environmental management. Received 4 October 2000; accepted 15 June 2001.  相似文献   

5.
In his analysis of U.S. legal prohibitions of marriage with relatives, Heider rejects the Old Testament model as an explanation of the configuration of current state laws. Although Heider's statement is generally accurate, the statutes seem to express two basic models, an attenuated Biblical and a Western American pattern. These patterns are the inverse of each other with regard to prohibition of first-cousin marriage and marriage between affines. Historical review of statutes reveals a trend from Biblical to Western American patterns. The historical perspective suggests that confounding the two models may have weakened Heider's analysis.  相似文献   

6.
This paper uses a variety of historical evidence from Indonesia to explore the conditions for sustainable management of natural resources. In the agricultural sphere, history gives reason for optimism regarding the ability of individuals to conserve and improve soil resources on an uncoordinated, anarchic basis under systems of intensive smallholder farming and agroforestry. It also suggests that this ability may be enhanced, rather than eroded, both by population growth and by the commercialization of agriculture. When it comes to the management of forests and fisheries and the conservation of nature, by contrast, there is less reason for optimism. If sustainable solutions are to be found in these spheres, the historical evidence suggests that they will involve political hierarchy, and will depend on the honouring of a social contract in which the state serves the public interest while retaining the powers of coercion which it needs in order to do just that.  相似文献   

7.
From Findley Lake and two ponds in the Cascade Mountains (U.S.A.) Chironomidae started to emerge as soon as the ice thawed in 1972 and 1973. The 1051 Chironomidae that emerged per m2 from Findley Lake included 307 individuals ofTanytarsus and 358 ofProcladius. Tanytarsus outnumberedChironomus at all depths from 0 to 19.3 m. The 1506 Chironomidae that emerged per m2 from the 4.5 m deep pond included 997 individuals ofTanytarsus. The 1490 Chironomidae that emerged per m2 from the 2 m deep pond included 1363 Tanytarsus. The emerging biomass was 216 and 186 mg dry weight per m2 in Findley Lake and the 4.5 m deep pond, respectively, and only 78 mg in the 2 m deep pond. Most species had their maximum emergence where there was organic detritus from the surrounding forest.Orthocladius emerged from sand bottom at 2.7 to 5.2 m depth.Stictochironomus emerged from mud and sand at 8.4 m depth.Chironomus emerged from soft mud at 15 to 27.5 m depth.  相似文献   

8.
9.
Beyond Territory and Scarcity: Exploring Conflicts over Natural Resource Management. Quentin Gausset, Michael A. Whyte, and Torben Birch-Thomsen, eds. Uppsala: Nordiska Afrikainstitutet, 2005. 218 pp.  相似文献   

10.
    
From data on interpopulation genetic structure of the Atlantic salmon from the rivers of the Barents, White and Baltic Sea basins on U.S.S.R. territory, it is suggested that salmon colonized the Onega and Pechora River basins from the Baltic drainage as the last ice-sheet receded, and that the Kola Peninsula rivers were colonized separately from the Barents Sea area.  相似文献   

11.
    
This cross-sectional study examined whether length of time in the U.S., language use, and birthplace (proxy measures of acculturation) were associated with body mass index (BMI) and obesity in a sample of 174 low-income Puerto Rican women from Hartford, Connecticut. The mean BMI for the total sample (N = 174) was 27.39 (S.D. = 5.07), and nearly 34% of the sample was considered obese (BMI > or = 30). There was a statistically significant increase in BMI with length of time in the U.S. (P = 0.012) and these differences were even greater among women born in Puerto Rico (P = 0.003). Moreover, obesity prevalence was highest among women who had been in the U.S. for 10 years or more (40%), as compared to those who had been in the U.S. less than 1 year (29%; P = 0.045). There were no statistically significant associations between language and BMI for the total sample. However, among bilingual speakers born in Puerto Rico, there were significant differences in BMI according to their level of English fluency. Those who spoke fluent or very good English had a significantly higher BMI (mean = 29.72; SD = 4.12) than women whose English was good to not-so-good (mean = 26.8; SD = 5.24; P = 0.016). The findings from this study point to the need for more research on the acculturation process and obesity, in order to design culturally tailored obesity prevention programs.  相似文献   

12.
A rat heart plasma membrane preparation isolated in a sucrose medium and some of its enzymatic properties have been investigated.It has been shown that a rat heart plasma membrane fraction contains high creatine phosphokinase activity which can not be diminished by repeated washing with sucrose solution. Creatine phosphokinase extracted from a plasma membrane fraction with potassium chloride and 0.01% deoxycholate solution is electrophoretically identical to MM isoenzyme of creatine phosphokinase. Under the conditions where (Na+,K+)-ATPase is activated by addition of Na+,K+ and MgATP, creatine phosphokinase of plasma membrane fraction is able to maintain a low ADP concentration in the medium if creatine phosphate is present. The rate of creatine release is dependent upon MgATP concentration in accordance with the kinetic parameters of the (Na+,K+)-ATPase and is significantly inhibited by ouabain (0.5 mM). The rate of creatine release is also dependent on creatine phosphate concentration in conformance with the kinetic parameters of MM isozyme of creatine phosphokinase,It is concluded that in intact heart cells the plasma membrane creatine phosphokinase may ensure effective utilization of creatine phosphate for immediate rephosphorylation of ADP produced in the (Na+,K+)-ATPase reaction.  相似文献   

13.
Lisa Robins 《EcoHealth》2007,4(3):247-263
This paper examines capacity-building measures used by the health sector relevant to natural resource management (NRM) using the delivery of two programs in Australia through its recently formalized 56 community-based regional NRM Boards as a reference point. The delivery of NRM outcomes through devolved governance arrangements has been hampered by inadequate capacity in other countries (e.g., New Zealand, Canada). The inherent complexities of NRM, coupled with professional “comfort zones,” often limit actors from looking to other sectors confronting similar issues. This paper summarizes findings from ∼70 sources in health reviewing nine major capacity-building measures. The outcomes of research evaluating the relative benefits and disbenefits of applying these measures are discussed. The paper identifies several opportunities to trial some of these measures in NRM.
Lisa RobinsEmail:
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14.
Much of the literature on the psychological treatment of victims of violence focuses on demographic populations that do not represent the majority of victims. Part of the origin of this problem is that the prototypical victim and the prototypical perpetrator are often the same. Young, poor, minority males often constitute both the victim and the perpetrator class in America. As a group, these individuals, while disproportionately thought of as suitable for incarceration, are not thought of as good candidates for psychological treatment. However, their suffering is real, unrelenting and often not addressed. Therapists face significant barriers, in the patient, in society and in themselves, in trying to help these individuals. This article examines the issues of racism, drugs, ongoing danger, class inequalities, misogyny and the blended victim/perpetrator, all of which complicate engagement and understanding between therapist and patient.  相似文献   

15.
Dyadic, reciprocal equilibrating relationships, such as trading partnerships in agrarian markets, have been reported from many societies. Data from a competitive marketplace in St. Louis, Missouri is analyzed in a multiple regression to test for the existence of such relationships between merchants and consumers. The interpretation of variables representing each firm's price level and consistency of stock reveals that economic custom is important even in this competitive marketplace.  相似文献   

16.
The mainstream view in natural resource management in African drylands has been that local people are responsible for natural resource degradation. Today, alternative views or new paradigms are emerging in several fields. These new paradigms, which support decentralization of natural resource management, are discussed in relation to the ongoing decentralization process in Mali. During the colonial period, heavily centralized governments were installed in all the French colonies. This structure was maintained by Malian governments after independence. However, following the recent transition to democracy, a decentralizing reform is being implemented. It is presently not clear whether these reforms will lead to mere deconcentration, involving the redistribution of administrative responsibilities within the central government, or whether Mali is heading toward real decentralization, devolving decision making powers to local communities. The gestion de terroir approach, which may be a useful tool in achieving decentralization in farming communities, would, in pastoral areas, cause more damage than benefit.  相似文献   

17.
The U.S. EPA is developing a new monitoring program, the Environmental Monitoring and Assessment Program (EMAP), to monitor and assess the ecological health of major ecosystems, including surface waters, forests, near-coastal waters, wetlands, agricultural lands, arid lands, and the Great Lakes, in an integrated, systematic manner. The program is designed to operate at regional and national scales, for decades, and to evaluate the extent and condition of entire ecological resources. EMAP has a common sampling framework for all resource types. The frame consists of a systematic grid of about 12,500 points in the conterminous United States that can be subdivided into subgrids of varying densities. A subset of 3,200 40 km2 hexagons will be selected for field sampling of surface water resources. A four-year resampling cycle will allow approximately 800 lakes and 800 stream sites to be evaluated annually. Ecological assessments for surface waters will address three environmental values of concern: biotic integrity, fishability, and trophic state. The focus will be on biological assemblages, including fish, zooplankton, macroinvertebrates, birds and diatoms, as response indicators of ecological condition.  相似文献   

18.
We have investigated the actions of beta-ecdysone and fat body on wing disks of Plodia interpunctella in a series of sequential incubations in vitro. These experiments revealed that extended treatment times of beta-ecdysone at concentrations of 0·5 μg/ml or greater inhibited development of disks, and confirm that the presence of a fat body factor in the culture medium prevents this inhibition.  相似文献   

19.
    
Objective: To examine the relationship between physical activity and inactivity patterns and overweight in U.S. adolescents using baseline and 1-year change in activity and inactivity data. Research Methods and Procedures: Nationally representative data from 12,759 participants (6997 non-Hispanic whites, 2676 non-Hispanic blacks, 2185 Hispanics, and 901 Asians) in the National Longitudinal Study of Adolescent Health (1995 and 1996). Data on moderate to vigorous and low-intensity physical activity, TV/video viewing, and video game/computer use were obtained from questionnaires. Multivariate models assessed the association of overweight (body mass index ≥ 95th percentile Centers for Disease Control and Prevention/National Center for Health Statistics 2000 curves) with initial (and 1-year change) activity and inactivity levels, controlling for age, ethnicity, socioeconomic status, urban residence, cigarette smoking, and region of residence. Results: Overweight prevalence was positively associated with high level TV/video viewing among white boys (odds ratio [OR] = 1.52; 95% confidence interval [1.08 to 2.14]) and girls (OR = 2.45 [1.51 to 3.97]). The odds of overweight decreased with high levels of moderate to vigorous physical activity among white boys (OR = 0.81 [0.76 to 0.87]), non-Hispanic black boys (OR = 0.86 [0.76 to 0.98]) and girls (OR = 0.88 [0.78 to 0.99]), and Hispanic boys (OR = 0.90 [0.83 to 0.97]) and girls (OR = 0.91 [0.84 to 0.99]). Discussion: Predicted probabilities generated from the logistic regression models, which examined the experimental effects of altering hours of TV/video viewing and bouts of moderate to vigorous physical activity, show lower overweight among adolescents who watched less TV per week combined with frequent moderate to vigorous physical activity than those who watched more TV per week combined with fewer bouts of weekly moderate to vigorous physical activity. Predicted probabilities suggest important sex and ethnic differences in these associations.  相似文献   

20.
The newly designed Army Collapsible Insect Surveillance trap for nocturnal collection of flying Diptera that are attracted by light is described. A polyvinyl chloride construction increases durability, while the capability to collapse from a height of 92.1 cm to 24.1 cm facilitates transportation and storage.  相似文献   

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