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131.
Removal of Prussian blue from contaminated soil in the rhizosphere of cyanogenic plants 总被引:1,自引:0,他引:1
The fate of radiolabeled cyanide in soil was investigated during exposure to cyanogenic plant species, sorghum (Sorghum bicolor var. P721) and flax (Linum usitassimum var. Omega-Gold), in fully-contained growth chambers. Labeled cyanide was subject to microbial transformation, assimilation by plant roots, incorporation and biodegradation in plant tissue. For this study, (14)C-labeled cyanide was added to soil, and distribution of (14)C activity was assessed before plant establishment and after harvest. After 3 months of plant growth, 7% of the (14)C-labeled cyanide was converted to (14)CO(2) with sorghum and 6% with flax, compared with only 2% conversion in unplanted soil. A small amount of unaltered cyanide was shown to be accumulated by the plants (approximately 140 mg cyanide/kg plant or <0.1% of the total). Results from this experiment demonstrate the potential of cyanogenic plants for use in phytoremediation of cyanide-contaminated soil. 相似文献
132.
Katherine Shields Andrew Fischer Chris Burke 《Journal of Environmental Planning and Management》2015,58(7):1270-1290
Discharge from the Great Barrier Reef Catchment (GBRC) is considered the second most serious threat to the Great Barrier Reef, Australia. Utilising principal component analysis (PCA) and cluster analysis (CA), this research aimed to assess the variability and co-variation of 28 water basins (WBs) within the GBRC, in order to improve the institutional arrangements and regulation of water quality and increase collaboration horizontally between management organisations, and vertically between government tiers. Water basin variability was measured by nine variables: size (ha), population, agricultural land use (ha), number of major water storages, major rivers and major towns, total nitrogen exported (T/yr), total phosphorus exported (T/yr) and herbicide use (ha). The Fitzroy WB, with PC scores of 7.0081, 2.2897 and ?1.6504, was identified as the most dissimilar and therefore needing to be managed differently. Many WBs within the same regions were very dissimilar to each other, indicating that current management practices, based largely on geographic location, are unlikely to be the most efficient and effective. Instead, managing groups of WBs with similar geo-political properties (determined by the CA) could be more effective and efficient. Coordination and collaboration are key to successful ecosystem based management, therefore managing similar WBs together through inter-NRM (natural resource management) agreements, irrespective of their geographical location, facilitates management bodies building strong, cooperative working relationships. 相似文献
133.
134.
Jennifer L. Cochran‐Biederman Katherine E. Wyman William E. French Grace L. Loppnow 《Conservation biology》2015,29(1):175-186
Reintroduction of imperiled native freshwater fish is becoming an increasingly important conservation tool amidst persistent anthropogenic pressures and new threats related to climate change. We summarized trends in native fish reintroductions in the current literature, identified predictors of reintroduction outcome, and devised recommendations for managers attempting future native fish reintroductions. We constructed random forest classifications using data from 260 published case studies of native fish reintroductions to estimate the effectiveness of variables in predicting reintroduction outcome. The outcome of each case was assigned as a success or failure on the basis of the author's perception of the outcome and on whether or not survival, spawning, or recruitment were documented during post‐reintroduction monitoring. Inadequately addressing the initial cause of decline was the best predictor of reintroduction failure. Variables associated with habitat (e.g., water quality, prey availability) were also good predictors of reintroduction outcomes, followed by variables associated with stocking (e.g., genetic diversity of stock source, duration of stocking event). Consideration of these variables by managers during the planning process may increase the likelihood for successful outcomes in future reintroduction attempts of native freshwater fish. Identificación de Correlaciones de Éxito y Fracaso de Reintroducciones de Peces de Nativos Agua Dulce 相似文献
135.
Begg Katherine Van der Horst Dan 《Mitigation and Adaptation Strategies for Global Change》2004,9(2):181-200
The European Union EU project PROBASE hasexplored a range of possible multi projectstandardised benchmarks as a way ofencouraging projects under Joint Implementation (JI) and the Clean Development Mechanism (CDM)by minimising transaction costs. The aim ofthis paper is to examine the environmentalintegrity of the use of standardisedbaselines and to explore the role ofadditionality. The environmental integritydepends on the uncertainty in emissionreductions, which was estimated bygenerating scenario baselines and comparingthese with the standardised baselines. Thishas allowed a comparison of selected multiproject baselines with the envelope ofuncertainty on the reductions. The projectsincluded a range of electricity supply,heat sector, cogeneration and methane(CH$_{4}$) projects in different countries. Theanalysis showed that the key uncertaintieswere in the technology fuel selection inthe baseline, the continued additionalityof the project emission reductions,uncertainties in some project emissions(e.g. spinning reserve emissions for wind)and data uncertainties. The effect on theestimation of reductions was in the range±12% to ±46% for the electricityprojects and from ±19% to ±57%for the heat and Combined Heat and Power CHP sector projects.Comparison with the envelope of uncertaintyfor the range of projects showed that multiproject electricity sector baselines whichhave been weighted or use high technologyperformance benchmarks (e.g. Organization for Economic Cooperation and Development OECD)can provide conservative estimates buttheir general nature can lead to variationsbetween countries. We would recommend thatthe country-specific context must be takeninto account so that standardised baselinesfor the electricity sector are generated onthe basis of country specificcharacteristics, the project type, andwhether it provides new or existing demand.The conservative scenario produced shouldthen be weighted. Whereas weightings havebeen applied to account for uncertaintiesor to bias towards renewables, we havesuggested a weighting factor of 25% on theelectricity baseline for large projectsbased on an analysis of the effect ofnon-additionality on emission reductionuncertainty. For heat projects, theappropriate benchmark is a technology/fuelbenchmark which is deemed relevant for theheat sector in that (part of the) country.Again we suggest that a weighted sectorbaseline is required to take account of theuncertainties. These recommendations applyto large projects only for a 10-yearcrediting lifetime. 相似文献
136.
The distribution and diet of juvenile (<750 mm) Patagonian toothfish are described from four annual trawl surveys (2003–2006)
around the island of South Georgia in the Atlantic sector of the Southern Ocean. Recruitment of toothfish varies inter-annually,
and a single large cohort dominated during the four years surveyed. Most juveniles were caught on the Shag Rocks shelf to
the NW of South Georgia, with fish subsequently dispersing to deeper water around both the South Georgia and Shag Rocks shelves.
Mean size of juvenile toothfish increased with depth of capture. Stomach contents analysis was conducted on 795 fish that
contained food remains and revealed that juvenile toothfish are essentially piscivorous, with the diet dominated by notothenid
fish. The yellow-finned notothen, Patagonotothen guntheri, was the dominant prey at Shag Rocks whilst at South Georgia, where P. guntheri is absent, the dominant prey were Antarctic krill and notothenid fish. The diet changed with size, with an increase in myctophid
fish and krill as toothfish grow and disperse. The size of prey also increased with fish size, with a greater range of prey
sizes consumed by larger fish. 相似文献
137.
Michael J. Scott James A. Dirks Katherine A. Cort 《Mitigation and Adaptation Strategies for Global Change》2008,13(4):307-339
US residential and commercial buildings were responsible for about 41 exajoules (EJ) of primary energy use per year in 2002,
accounting for approximately 9% of the world fossil-fuel related anthropogenic carbon (C) emissions of 6.7 Gt that contribute
to climate change. US Government-sponsored building energy efficiency research and implementation programs are focused on
reducing energy consumption in US residential and commercial buildings and reducing these carbon (C) emissions. Although not
specifically intended for adaptation to a warmer climate and less effective than under today’s cooler climate, these programs
also could help reduce energy demand in a future warmer world. Warming scenarios projected by the United Nations Intergovernmental
Panel on Climate Change (IPCC) in 2001 imply net overall decreases in both site energy and primary energy consumption in US
residential and commercial buildings, largely because of the reduced need for heating. However, there would be as much as
a 25% increase in building space cooling demand and a significant part of the increase could be offset by energy-efficiency
improvements in buildings. Overall, in the US, buildings-related energy efficiency programs would reduce site energy consumption
in buildings in the US by more than 2 EJ in 2020 and primary energy by more than 3.5 EJ, more than enough to offset the projected
growth in cooling energy consumption due to climate change and growth in the US building stock. The savings would have an
estimated annual net value at 2005 energy prices of between $45.0 and $47.3 billion to consumers.
相似文献
Michael J. ScottEmail: |
138.
Ralf M. Staebler Sean M. McGinn Brian P. Crenna Thomas K. Flesch Katherine L. Hayden Shao-Meng Li 《Atmospheric environment (Oxford, England : 1994)》2009,43(38):6091-6099
In Canada approximately 45% of ammonia (NH3) emissions are attributed to dairy and beef cattle industries. The present study focused on NH3 emissions from a beef feedlot with a one-time capacity of 17,220 head. The aim was to improve the Canadian NH3 emission inventories and air quality forecasting capabilities. A Cessna 207, equipped with a fast-response NH3/NOy detector and a quadrupole aerosol mass spectrometer, was flown in a grid pattern covering an area of 8 × 8 km centered on a feedlot (800 × 800 m) at altitudes ranging from 30 to 300 m above ground. Stationary ground measurements of NH3 concentration and turbulence parameters were made downwind of the feedlot. Three flights were conducted under varying meteorological conditions, ranging from very calm to windy with near-neutral stratification. NH3 mixing ratios up to 100 ppbv were recorded on the calm day, up to 300 m above ground. An average feedlot NH3 emission rate of 76 ± 4 μg m?2 s?1 (equivalent to 10.2 g head?1 h?1) was estimated. Characteristics of the measured NH3 plume were compared to those predicted by a Lagrangian dispersion model. The spatially integrated pattern of NH3 concentrations predicted and measured agreed but the measured was often more complex than the predicted spatial distribution. The study suggests that the export of NH3 through advection accounted for about 90% of the emissions from the feedlot, chemical transformation was insignificant, and dry deposition accounted for the remaining 10%. 相似文献
139.
140.
Katherine E. Moseby Hugh McGregor Brydie M. Hill John L. Read 《Conservation biology》2020,34(1):220-231
Spillover effects are an expansion of conservation benefits beyond protected areas through dispersal of species that reside within. They have been well documented in marine but not terrestrial systems. To understand the effects on wildlife created by conservation fences, we explored the internal and external gradients of activity in mammal, reptile, and bird species at a conservation reserve in arid Australia that is fenced to exclude invasive rabbits (Oryctolagus cuniculus), cats (Felis catus), and foxes (Vulpes vulpes). Two methods were used: counts of animal tracks along transects on sand dunes and captures at pitfall-trapping sites. In both cases, sites were spaced at different distances from the reserve fenceline inside and outside the reserve. We recorded a range of spillover, source-sink, step, and barrier effects that combined to create a zone within and around the reserve with fence-induced species-specific wildlife gradients. Two endemic rodents but none of the 4 mammal species reintroduced to the reserve showed positive spillover effects. Barrier effects, where activity was highest close to the fence, were recorded for the feral cat and native bettong (Bettongia lesueur), species that could not breach the fence. In comparison, some reptiles and native mammal species that could permeate the fence displayed source-sink effects; that is, their activity levels were reduced close to the fence likely due to constant emigration to the side with lower density. Activity of some reptiles was lowest at sites inside the reserve and gradually increased at outside sites with distance from the fence, a gradient likely related to trophic cascades triggered by predator exclusion. Our result shows that fenced reserves can create overlapping layers of species-specific gradients related to each species’ ability to permeate the fence and its varying susceptibility to threats. Managers should be aware that these gradients may extend for several kilometers either side of the fence and that not all contained species will increase in abundance. Creating wider conservation benefits may require increased fence permeability and threat reduction outside the fence. 相似文献