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Evaluators frequently cite the absence of effective participation by constituent governments and the need for consensus or even unanimity prior to action as the causes of poor performance by regional resource management institutions. Major governments either will not join the regional institution, will not participate even if legally members, or will exercise a veto over many important management projects.This paper examines the variables that may cause these problems and provides an improved understanding of why rational political actors would act in ways that inhibit the efficient management of resources. Among the principal variables determining participation are expected benefits of collective decisions, perceived losses of autonomy and representation, the number and homogeneity of other participants, decision costs, and the decision rule used to determine actions. Analysis of these factors suggests why consensus and unanimity decision rules are frequently chosen and why participation is usually limited. 相似文献
254.
Douglas W. Kuehl Edward N. Leonard Brian C. Butterworth Kenneth L. Johnson 《Environment international》1983,9(4):293-299
Over 50 non-PCB polyhalogenated organic chemicals have been identified by GC/MS in fish from the Great Lakes and other major watersheds near the Great Lakes. p,p′-DDE, hexachlorobenzene, and components of tech-chlordane were the most frequently found chemicals. Also described are advances in sample preparation methodology which allow the identification of many frequently occuring unusual chemicals. Several chemicals not previously reported in environmental samples are identified. 相似文献
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Mathematical modeling of competing risks often uses a single risk function for all individuals within a population. In this paper we use several specific examples to argue that such representations remain approximations until account is taken of the existence of genetic variability within and between populations, and the impact of this upon liability to disease. The extent of human genetic variability is also indicated. 相似文献
258.
OBJECTIVES: To compare drivers who were: (1) exposed to Maryland's sobriety "Checkpoint Strikeforce" campaign; (2) not exposed but were aware of it; and (3) neither exposed nor aware of it. This six-month campaign involved periodic road-side sobriety checkpoints, in which police attempted to detect and arrest drunk drivers and a series of radio Public Service Announcements (PSAs) that promoted public awareness. METHODS: A statewide sample of 1725 drivers were interviewed by telephone to determine their exposure to and awareness of this campaign, as well as their beliefs and behaviors concerning drunk driving and seat belt usage. RESULTS: Relatively few people (9.6%) were exposed in any way to the campaign; however almost 30% were aware of it. Significant increases in perceived vulnerability to arrest for drinking and driving were found among those who were exposed. There were no differences in reported drinking and driving, but seat belt usage in the last 30 days was higher among those who were exposed. There were no differences among those people who had been directly exposed to the campaign (i.e., personally gone through a sobriety checkpoint) and those who were indirectly exposed (i.e., knew a family member or someone else who went through a checkpoint). CONCLUSIONS: Exposure to a sobriety checkpoint was associated with increased perceptions of drink-driving risk (i.e., likelihood of getting caught by the police), which was not dependent upon having personally experienced it. Awareness without exposure appears to be insufficient to change perceived risk. The need to increase the reach and frequency of the sobriety "Checkpoint Strikeforce" campaign is indicated. 相似文献
259.
Woodard KR French EC Sweat LA Graetz DA Sollenberger LE Macoon B Portier KM Wade BL Rymph SJ Prine GM Van Horn HH 《Journal of environmental quality》2002,31(6):1980-1992
Florida dairies need year-round forage systems that prevent loss of N to ground water from waste effluent sprayfields. Our purpose was to quantify forage N removal and monitor nitrate N (NO3(-)-N) concentrations in soil water below the rooting zone for two forage systems during four 12-mo cycles (1996-2000). Soil in the sprayfield is an excessively drained Kershaw sand (thermic, uncoated Typic Quartzipsamment). Over four cycles, average loading rates of effluent N were 500, 690, and 910 kg ha(-1) per cycle. Nitrogen removed by the bermudagrass (Cynodon spp.)-rye (Secale cereale L.) system (BR) during the first three cycles was 465 kg ha(-1) per cycle for the low loading rate, 528 kg ha(-1) for the medium rate, and 585 kg ha(-1) for the high. For the corn (Zea mays L.)-forage sorghum [Sorghum bicolor (L.) Moench]-rye system (CSR), N removals were 320 kg ha(-1) per cycle for the low rate, 327 kg ha(-1) for the medium, and 378 kg ha(-1) for the high. The higher N removals for BR were attributed to higher N concentration in bermudagrass (18.1-24.2 g kg(-1)) than in corn and forage sorghum (10.3-14.7 g kg(-1)). Dry matter yield declined in the fourth cycle for bermudagrass but N removal continued to be higher for BR than CSR. The BR system was much more effective at preventing NO3(-)-N leaching. For CSR, NO3(-)-N levels in soil water (1.5 m below surface) increased steeply during the period between the harvest of one forage and canopy dosure of the next. Overall, the BR system was better than CSR at removing N from the soil and maintaining low NO3(-)-N concentrations below the rooting zone. 相似文献
260.
Runoff from sloping landscapes cropped with established alfalfa (Medicago sativa L.) may contain bioavailable P (BAP) which accelerates eutrophication of surface water bodies. Such BAP exists as either dissolved reactive P (DRP) or bioavailable reactive particulate P (BPP). We hypothesized that before and after harvest, sod-forming smooth bromegrass (Bromus inermis Leyss.) or alfalfa-smooth bromegrass mixtures would have less BAP, DRP, and BPP runoff losses than taprooted alfalfa. Swards established in 1992 near Lancaster, WI were subjected to a 72 mm simulated rainfall applied for 1 h in 1993 and 1994 to forage regrowth at 4 and 6 wk after first harvest and immediately (0 wk) after second harvest. Hourly BAP losses for all sward types were 82% less when 1.5 Mg ha(-1) of forage dry matter was present. High DRP losses (>0.050 kg ha(-1)) were associated with high DRP concentrations (>7.1 micromol L(-1)) and high surface soil P concentrations (>59 mg kg(-1)) resulting from broadcast maintenance P fertilizer. High BPP losses (>0.035 kg ha(-1)) were associated with high runoff volumes (>24 mm) and sediment concentrations (>2 g L(-1)). Summed over all 6 rainfall simulations, total BAP loss was only 0.07 kg ha(-1) at the 6 wk stage of regrowth compared with 0.35 at 4 wk, and 0.41 at 0 wk. Moreover, there was no significant difference between sward types for DRP concentration, DRP loss, or BAP loss. We conclude that avoiding excessive defoliation was more effective at reducing BAP losses than specific forage species selection. 相似文献