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1.
Sodium monofluoroacetate (1080) is a mammalian pesticide used in different parts of the world for the control of mammalian pest species. In New Zealand it is used extensively and very successfully as a conservation management tool for the control of brushtail possums (Trichosurus vulpecula) – an introduced marsupial that has become a substantial agricultural and conservation management pest. Possums pose a threat to cattle farming in New Zealand as they are a vector for bovine tuberculosis. In protected natural areas, possum browsing is responsible for large scale defoliation of native vegetation. As with many other pesticides, there has been some degree of popular concern about the use of this toxin and its safety, with particular reference to non-target effects. These concerns have been associated with potential non-target effects on human health, and the health of animals of recreational value (e.g., hunting dogs and game animals). This has led to the development of a strong “anti-1080” lobby in New Zealand. In contrast, this study encompasses a science-based risk analysis focusing on the potential risks to non-target native wildlife with a particular focus on chronic toxicity. It finds that there is evidence that 1080 may have endocrine disrupting capabilities (with potential relevance for non-target wildlife) but that this still needs more detailed investigation. This can be clarified by further targeted research. Further research is also needed to test the degradation rates of 1080 and its breakdown products at ecologically-relevant temperatures (i.e., winter stream temperatures – below 11 °C). Such research may demonstrate that some adjustment to 1080 risk management is warranted in New Zealand, or it may help to put to rest the current controversy over the use of this cost effective conservation management tool.  相似文献   

2.
Abstract: For a number of years, best management practices (BMPs) have been implemented within the Town Brook watershed as part of a watershed wide effort to reduce phosphorus losses to the New York City water supply reservoirs. Currently, there are no quantitative indications of the effectiveness of these practices at the watershed scale. Additionally, work is needed to evaluate management practice solutions for costs in relation to effectiveness. In this study we develop a methodology for evaluating management solutions to determine the best way(s) to select and place management practices so that pollutant removal targets are met at minimum cost. The study combines phosphorus losses as simulated by the Soil and Water Assessment Tool (SWAT), management practice effectiveness estimates from a predeveloped characterization tool, and practice costs in optimizations using a genetic algorithm. For a user defined target phosphorus removal (60 percent for this study), optimization favors nutrient management plans, crop rotations, contour strip cropping, and riparian forest buffers; the most cost effective scenario achieves a cost effectiveness of 24/kg phosphorus removal per year compared to the 34/kg phosphorus removal per year associated with the current basic implementation scheme. The study suggests that there is a need to evaluate potential solutions prior to implementation and offers a means of generating and evaluating the solutions.  相似文献   

3.
This paper discusses the complexity of the protected area mosaic that has evolved in the United Kingdom over the past 40 or so years. Experimental matrices have been used to assist in the analysis of the various types of protected areas. The trend has been towards the development of protected areas to serve multiple objectives, although categories of protected area introduced under European legislation are more narrowly defined. There has been a proliferation in the number of categories of protected area in the past ten years; since 1990 six new categories of protected area have been established, two resulting from European directives. Most of the protected areas operate indirectly through the planning system and/or voluntary agreements. However, a distinction is drawn between systems for nature conservation and landscape protection with the former relying more on direct controls (ownership and/or legal force). There is considerable potential overlap of protected areas. New categories of protected area have often been superimposed upon the existing system without consideration of whether they will result in duplication of effort, expenditure etc. We conclude that there is scope for some rationalization of the system. Ideally this would involve replacing existing protected areas with broader based ones but considerable simplification could be obtained in practice by making the powers of the agencies more flexible and changing the administrative arrangements for managing the various protected areas.  相似文献   

4.
ABSTRACT: Integrated watershed management encompasses complex physical and social issues that have impacts on environmental resources. A key aspect of this holistic effort is public education. Most researchers and practitioners agree that an informed public is a crucial part of the environmental management process. Yet, educational programs that provide stakeholders with information about physical processes in watersheds are often unavailable. This paper assesses the effect of an education program for residents of the New York City watershed. Surveys evaluated certain knowledge levels and attitudes of participants and compared three groups: individuals who utilized the educational materials completely (full users), those who received the materials but did not use them completely (partial users), and watershed residents who did not receive the educational program (nonrecipients). Full users displayed a higher level of knowledge concerning specific watershed processes than did partial users and nonrecipients. In terms of applying that knowledge across linked concepts, however, we observed no significant differences between the three readership levels. Furthermore, partial users engaged in less evaluation of issues that related to the broader watershed context. The findings from this project have implications for educational and regulatory institutions and program development relating to watershed protection.  相似文献   

5.
ABSTRACT: Considerable effort is expended each year in making flood peak estimates at both gaged and ungaged sites. Many methods, both simplistic and complex, have been proposed for making such estimates. The hydrologist that must make an estimate at a particular site is interested in the accuracy of the estimate. Most methods are developed using either statistical analyses or analytical optimization schemes. While publications describing these methods often include some statistical measure of goodness-of-flt, the terminology often does not provide the potential user with an answer to the question,‘How accurate is the estimate?’ That is, statistical terminology often are not used properly, which may lead to a false sense of security. The use of the correct terminology will help potential users evaluate the usefulness of a proposed method and provide a means of comparing different methods. This study provides definitions for terms often used in literature on flood peak estimation and provides an interpretation for these terms. Specific problems discussed include the use of arbitrary levels of significance in statistical tests of hypotheses, the identification of both random and systematic variation in estimates from hydrologic methods, and the difference between accuracy of model calibration and accuracy of prediction.  相似文献   

6.
Stakeholder participation is expected to improve the efficiency, equity, and sustainability of natural resource management research and development (R&D) projects by ensuring that research reflects users’ priorities, needs, capabilities, and constraints. Use of participatory methods and tools is growing rapidly; however, there is little systematic evidence about what participation actually means in practice, or about what difference it makes. Based on an inventory of 59 self‐described participatory R&D projects in the area of natural resource management, this article characterizes the typical project and analyzes how stakeholders are selected, how they participate in the research process, and what their involvement means for project costs and impacts. The results suggest that, while projects are generating a range of direct and indirect benefits for participants, more careful attention needs to be paid to achieving equitable impacts. Current practices may lag behind best practices in key areas, such as power sharing and participant selection, and may therefore be missing important contributions from women and other marginalized groups.  相似文献   

7.
ABSTRACT: This paper describes the development of an interdisciplinary model that analyzes the effects of resource management decisions on New Mexico fishery production, yield, sportfishing effort, and economic benefit to anglers. The model recreates river flows and materials transported through reservoirs and their tailwaters from 1974 through 1987. Solar radiation, water temperature, phosphorus, nitrogen, suspended solids, and water exchange rates determine primary production. Organic loads from watershed sources, added to primary production, form a trophic base for sportfish forage. Fish production is partitioned into biomass and growth of each age class in sportfish and forage fish groups by differential responses to food type, light, water-level fluctuation and predation. Fish biomass, with angler population distribution and site condition, contributes to determining angler effort and economic benefits. Model users can vary and analyze water level and quality, stocking, fishing regulations, site access, site facilities, and site entry fees. The model (on floppy disks with a user manual) is available for operation on MS DOS compatible computers with a hard disk. Contact R. M. Wilson, NMGF, State Capitol, Santa Fe, New Mexico, 87503.  相似文献   

8.
许碧君  陆光华 《四川环境》2006,25(5):87-90,117
应用水生生物胆碱脂酶作为生物标志物对水环境中有机磷和氨基甲酸盐杀虫剂的暴露和效应进行评价日益受到重视。它作为一种快捷有效的监测工具,将会在环境监测中得到越来越广泛深入的应用。本文介绍了该生物标志物的作用原理、应用方向,以及检测酶活性抑制的研究方法,并对它的影响因子进行分析。最后阐述了发展前景。  相似文献   

9.
ABSTRACT: The power of computers has increased in recent decades, and one might expect improved management to result because decisions can be made with understanding available only via models. However, there is potential for quite the opposite: poor decisions due to unrealistic model output generated by users without access to appropriate training in the use of models. We discuss and, by reference to water demand models (IWR-MAIN, MWD-MAIN), illustrate three areas in which unintended errors of judgment by untrained personnel may cause difficulty:
  • * Attributes of management models; if output from any type of model has no measure of confidence, then results may be over- or undervalued
  • * Input data; with complex models, problems here typically will be difficult to detect.
  • * Calibration and history-matching (verification); if these steps or data are combined, then users should be less trustful of model output than otherwise.
Because all models have weaknesses and because there always is uncertainty about output from any model, we end with suggestions for coping with complex models. Monitoring programs play a central role in such efforts because they can identify discrepancies between model predictions and actual events and because they can ensure time is available to develop solutions for problems unanticipated in the modeling effort.  相似文献   

10.
The rapid development of wireless technologies leads to increased human exposure to electromagnetic fields from new devices. Most of these technologies communicate in short to medium range. Communication devices, such as mobile phones (GSM, UMTS, LTE) and wireless computer networks (WLAN, HSDPA, WIMAX) usually work at distances up to some 10 km. Other techniques like Bluetooth, RFID, and wireless USB work at distances up to a few meters. RFID systems can use several frequency bands from low frequencies up to microwaves. The other technologies are mainly using microwave frequencies. Most of these technologies have a rather low-output power, typically <1 W average power, except for fixed transmitters like base stations. This means that the exposure from distant sources is low. If the devices are kept close to the body, the local exposure can be in the range of the levels in the ICNIRP recommendation; this is the case, for example, for mobile phones and WLAN transmitters in laptops. For distant sources, there exist several measurement techniques such as spectrum analysers, measurement receivers, and broadband meters. For sources used close to the body, the local SAR levels have to be determined. For this purpose, instruments measuring the local electric field inside body phantoms have been developed. An alternative to measurements is numerical simulations. If one has knowledge of the signal characteristics of the different technologies then it is possible to find a suitable measurement technique to assess the human exposure.  相似文献   

11.
ABSTRACT: The aim of this paper is to present a multicriteria methodology for decision aid at the stage of programming a water supply system (WSS) for a rural area. The programming stage is an intermediate one between planning and designing water supply facilities, and can be decomposed into two problems: (a) setting up a priority order of water users, taking into account socio-economic criteria; and (b) choosing the best technical variant of the WSS. Among the criteria considered for the latter problem, there is a criterion of distance between the socio-economic priorities of users and the precedence orders of users according to the technical programming, which plays a coordinating role between problems (a) and (b). All steps of the presented methodology are illustrated by a real case study.  相似文献   

12.
ABSTRACT: Municipalities will be implementing structural best management practices at increasing rates in their effort to comply with Phase II of the National Pollutant Discharge Elimination System (NPDES). However, there is evidence that structural best management practices (BMPs) by themselves may be insufficient to attain desired water quality standards. This paper reports on an analysis of the median removal efficiencies of structural BMPs and compares them to removal efficiencies estimated as being necessary to attain water quality standards in the Rouge River in Detroit, Michigan. Eight water quality parameters are reviewed using data collected from 1994 to 1999 in the Rouge River. Currently, five of the eight parameters in the Rouge River including bacteria, biochemical oxygen demand, and total suspended solids (TSS) exceed the required water quality standards. The reported analysis of structural BMP efficiencies reveals that structural BMPs appear capable of reducing only some of the pollutants of concern to acceptable levels.  相似文献   

13.
ABSTRACT: Site specific studies of water based recreation participation are intended to describe use at a particular recreation area. Two common strategies employed in site specific studies are the on-site “entry” or “exit” survey and the off-site mailed questionnaire to known users of an area. Previous research has reported differences in psychological perceptions of a recreation engagement depending on whether a survey was administered during or after a trip. If such bias exists for behavioral reports, then managers and planners must be cautious in interpreting results of survey based use assessments for a particular site. Findings may be affected by the particular survey strategy employed. In this study, entry point and post-trip mailed questionnaire measures of water based recreation participation were compared for a sample of reservoir users. For most activities, a high degree of consistency in measures was found. Inconsistent reports were most likely to occur among participants in activities sharing significant common behaviors, such as power boating and water skiing. Inconsistency was also observed for those reporting very generalized behaviors, such as relaxing. In general, the use of either pre- or post-trip measures of water based recreation participation was supported.  相似文献   

14.
Many recreational anglers practice catch-and-release angling, where fish are returned to the water with the presumption that they will survive. However, not all fish survive, and those that do often experience sublethal consequences including injury and stress. There is compelling scientific evidence that angler behavior and gear choice can affect the success of catch-and-release as a management and conservation strategy. Because anglers often look to government natural resource agencies for guidance on how to handle and release fish properly, there is a need to assess whether their outreach materials are readily accessible and provide the necessary and correct information on the subject. Therefore, on-line catch-and-release guidelines developed by state and provincial natural resource agencies across North America were evaluated to determine whether their guidelines were consistent with the best available scientific information. This analysis revealed that there was immense variation in the depth and breadth of coverage among jurisdictions. Agency guidelines contradicted one another in several areas including air exposure, angling in deep water, venting trapped gases, and resuscitation. In many cases, the guidelines failed to provide sufficient direction to actually be of use to anglers or provide direction consistent with contemporary scientific literature. This analysis will assist with developing outreach materials that promote sustainable recreational fisheries and in maintaining the welfare status of individual fish.  相似文献   

15.
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17.
An important aspect of developing a philosophical foundation for management of reserves using an ecosystem approach is the exploration of the relationship of ecosystem management strategies to the need for conservation of species of special concern Colonial water birds are species that may deserve special consideration They occur in over 25 US national parks, but in no case do the parks have a monopoly on the total protection or management of these birds As an agency responsible for such populations, the National Park Service engages in activities such as inventory, monitoring, research, and management, using an ecosystem management philosophy Most parks contain only segments of natural ecosystems, and management actions, even those undertaken from an ecosystem perspective, may not be in the best interest of an individual species Management strategies for widely ranging special species require a regional perspective, including plans that take into consideration the differing objectives of the agencies responsible for such species A matrix of the different management strategies in various areas may provide a suitable, perhaps the best, method for protecting special species In practice, any one strategy, such as management of remnant ecosystem patches or intensive single-species management, may not be successful alone  相似文献   

18.
Advocates of eating locally offer a wide range of arguments in favor of the practice, but their ethical import is not always clear. Some locavore statements and arguments seem to imply a strong form of moral obligation; that eating locally is not merely instrumental to some other good, but has intrinsic value in its own right. This article examines standard arguments on behalf of eating locally, including arguments linked to the value of small farms and agrarianism, the environment, taste and health, trust, and relational markets. Most arguments put forward on behalf of eating locally value it instrumentally, the main exception being arguments based on relational markets. Although these arguments provide important motives for eating locally, the strength of obligation varies widely, and even the strongest arguments possess significant qualifications. While eating locally can play a role in reducing environmental impacts, this is not necessarily so, and once removed from instrumental considerations, eating locally is more likely at best an imperfect duty.  相似文献   

19.
Sustainable labels are considered the best way for consumers to identify brands with environmental or social attributes on the shelves, and therefore promoted as a means to develop the so-called “ethical markets”. However, little is known about how consumers use these brands. This paper tries to offer complementary theoretical insights on the determinants of sustainable label use by drawing on the economic model of information search; in particular, it examines the influence of two factors on the purchase of such labels: motivation and knowledge. Information was gathered through a structured questionnaire in personal interviews with 289 primary buyers. The study found that education influences directly knowledge, while Motivation influences Label use both directly and indirectly, via Label knowledge. This study concludes that Motivation is the most powerful factor to explain Label use; knowledge is a necessary but not sufficient condition. Even more, consumers may not have a good understanding of sustainable labels and still use them in their purchasing decisions. This suggests that there is a dual processing mode of sustainable labels, both systematic and heuristic.  相似文献   

20.
The United Kingdom offers some of the finest designed parks and garden landscapes in the world and, whilst there is a wide range of skills and a wealth of literature on the subject, there is little evidence of official effort to systematically record historic sites. This, it is argued, is a factor in the continuing decline of many examples. This paper records an attempt at a comprehensive examination of one county — Cheshire — begun in 1970. The method is described and the results discussed in some detail. Some suggestions are put forward for improvements to official incentives for site owners.  相似文献   

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