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121.
122.
Agriculture is a key land user implicated in the causes of, and solutions to, the problem of biodiversity decline. The development, in the late 1990s, of farm biodiversity action plans (farm BAPs) represents an important step towards achieving greater farmer involvement in biodiversity and is the first specific attempt to devise a practical mechanism for meeting biodiversity targets at the farm level. In this paper the processes surrounding the design and implementation of farm BAPs are used to explore how farmers are responding to the biodiversity issue and to highlight challenges and opportunities being faced by the organizations delivering biodiversity to the farming community. It describes the formulation and operation of farm BAPs, and then moves on to present two conceptual domains, governance and ecological modernization, which provide a framework for interpreting the emergence of farm BAPs. Following a brief elaboration of methodology, the paper presents and discusses selected findings from empirical research into farm BAPs across the UK. 相似文献
123.
Differential Assessment of Designations of Wetland Status Using Two Delineation Methods 总被引:1,自引:0,他引:1
Two different methods are commonly used to delineate and characterize wetlands. The U.S. Army Corps of Engineers (ACOE) delineation method uses field observation of hydrology, soils, and vegetation. The U.S. Fish and Wildlife Service’s National Wetland Inventory Program (NWI) relies on remote sensing and photointerpretation. This study compared designations of wetland status at selected study sites using both methods. Twenty wetlands from the Wetland Boundaries Map of the Ausable–Boquet River Basin (created using the revised NWI method) in the Ausable River watershed in Essex and Clinton Counties, NY, were selected for this study. Sampling sites within and beyond the NWI wetland boundaries were selected. During the summers of 2008 and 2009, wetland hydrology, soils, and vegetation were examined for wetland indicators following the methods described in the ACOE delineation manual. The study shows that the two methods agree at 78 % of the sampling sites and disagree at 22 % of the sites. Ninety percent of the sampling locations within the wetland boundaries on the NWI maps were categorized as ACOE wetlands with all three ACOE wetland indicators present. A binary linear logistic regression model analyzed the relationship between the designations of the two methods. The outcome of the model indicates that 83 % of the time, the two wetland designation methods agree. When discrepancies are found, it is the presence or absence of wetland hydrology and vegetation that causes the differences in delineation. 相似文献
124.
Julie A. Mansfield Yadetsie N. Zaragoza-Rivera Gretchen H. Baker John H. Bolte IV 《Traffic injury prevention》2019,20(5):534-539
Objectives: The objective of the study is to determine whether specific child restraint system (CRS) or vehicle conditions improve top tether attachment rates during volunteer installations.Methods: A factorial randomized controlled trial was designed to evaluate 4 different experimental categories: (1) Color of tether adjuster casing (black or red), (2) labeling on tether adjuster casing (labeled with “Tether: Use for forward-facing” or unlabeled), (3) storage location of tether (bundled in a rubber band on the back of CRS or Velcroed over the forward-facing belt path), and (4) labeling in vehicle (labeled under head restraint and below anchor or unlabeled). Ninety-six volunteers were randomly assigned to one combination of conditions. One installation per volunteer was completed. The primary outcome measure was acceptable attachment of the top tether to the tether anchor. The secondary outcome measure was overall secureness of the installation. Pearson’s chi-square tests were used to identify significant predictors of acceptable outcomes and logistic regression was used to investigate interaction effects.Results: A total of 66/96 subjects (68.8%) attached the top tether in an acceptable manner, with either zero errors (n?=?50) or minor errors (n?=?16). A total of 30/96 subjects (31.2%) had unacceptable tether outcomes, with either major errors (n?=?10) or nonuse the tether at all (n?=?20). None of the 4 experimental categories significantly affected tether outcomes. Subjects who opted to install the CRS with the lower anchors (LAs) had higher rates of acceptable tether attachment compared to subjects who installed using the seat belt or those who used both LA and seat belt together (χ2 = 6.792, P = .034). Tether outcomes were not correlated with previous CRS experience, use of instruction manual(s), age, or sex. Only 15.6% of subjects produced overall correct and tight installations. Of those who used the seat belt in some manner, 70.2% neglected to switch the retractor into locking mode.Conclusions: Conditions in this study including tether color, tether labeling, storage location, and vehicle labeling did not significantly affect tether attachment rates. High rates of tether misuse and nonuse warrant further exploration to find effective solutions to this usability problem. 相似文献
125.
Katrina F. Phillips Katherine L. Mansfield David J. Die David S. Addison 《Marine Biology》2014,161(4):863-870
Few long-term mark-recapture tagging datasets exist to estimate population parameters for loggerhead sea turtle (Caretta caretta) recovery units. Using a two-state open robust design model, we analyzed a 20-year (1990–2009) mark-recapture dataset from the Keewaydin Island loggerhead nesting assemblage off the southwest coast of Florida (USA) in the eastern Gulf of Mexico. For this analysis, 2,292 turtle encounters were evaluated, representing 841 individual nesting turtles. Survival was estimated at 0.73 (95 % CI 0.69–0.76). This estimate is comparable with survival estimates elsewhere in the Peninsular Florida subpopulation and is among the lowest estimates for the Northwest Atlantic loggerhead population. We documented no changes in remigration rates or clutch frequency over time. These are the first survival and remigration probabilities estimated for a loggerhead nesting assemblage in the eastern Gulf of Mexico. 相似文献
126.
127.
Clausen CA 《Waste management (New York, N.Y.)》2004,24(4):407-411
Remediation processes for recovery and reuse of chromated-copper-arsenate- (CCA) treated wood are not gaining wide acceptance because they are more expensive than landfill disposal. One reason is the high cost of the nutrient medium used to culture the metal-tolerant bacterium, Bacillus licheniformis, which removes 70-100% of the copper, chromium, and arsenic from CCA-treated southern yellow pine (CCA-SYP) in a two-step process involving oxalic acid extraction and bacterial culture. To reduce this cost, the nutrient concentration in the culture medium and the ratio of wood to nutrient medium were optimized. Maximum metal removal occurred when B. licheniformis was cultured in 1.0% nutrient medium and at a wood to nutrient medium ratio of 1:10. Also, malted barley, an abundant by-product of brewing, was evaluated as an alternative nutrient medium. Tests were done to determine absorption of metals by barley, and the results indicate that the barley acted as a biosorbent, removing heavy metals from the liquid culture after their release from CCA to SYP. For comparison, tests were also performed with no nutrient medium. Following bacterial remediation, 17% copper and 15% arsenic were removed from an aqueous slurry of CCA-SYP (no medium). When oxalic acid extraction preceded the aqueous bacterial culture, 21% copper, 54% chromium, and 63% arsenic were removed. The two-step process (oxalic acid extraction and bacterial culture with nutrient medium) appears to be an effective, yet costly, way to remove metals. 相似文献
128.
The use of seaweed as an agricultural soil conditioner gives rise to a potential pathway for the transfer of Technetium-99 ((99)Tc) from marine to terrestrial ecosystems and thence to man. However, to date there is little information on the extent of the release of (99)Tc from seaweed into soil and the mechanisms involved. This pot experiment has shown that (99)Tc is released fairly rapidly from Fucus vesiculosus into a sandy coastal soil. Despite low temperature conditions, 60% of the (99)Tc added with the seaweed had accumulated in the soil 15 weeks after addition. Concurrent CO(2) monitoring (used as a measure of microbial decomposition or catabolism) suggested that the initial (99)Tc release (up to 40% in the first 8 weeks) was due to leaching from the seaweed and that microbial decomposition was responsible for the release of the remaining (99)Tc in the latter phase (12-15 weeks). 相似文献
129.
130.
Thomas E. Croley Carol L. Luukkonen 《Journal of the American Water Resources Association》2003,39(1):149-163
ABSTRACT: Computer simulations involving general circulation models, a hydrologic modeling system, and a ground water flow model indicate potential impacts of selected climate change projections on ground water levels in the Lansing, Michigan, area. General circulation models developed by the Canadian Climate Centre and the Hadley Centre generated meteorology estimates for 1961 through 1990 (as a reference condition) and for the 20 years centered on 2030 (as a changed climate condition). Using these meteorology estimates, the Great Lakes Environmental Research Laboratory's hydrologic modeling system produced corresponding period streamflow simulations. Ground water recharge was estimated from the streamflow simulations and from variables derived from the general circulation models. The U.S. Geological Survey developed a numerical ground water flow model of the Saginaw and glacial aquifers in the Tri‐County region surrounding Lansing, Michigan. Model simulations, using the ground water recharge estimates, indicate changes in ground water levels. Within the Lansing area, simulated ground water levels in the Saginaw aquifer declined under the Canadian predictions and increased under the Hadley. 相似文献