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21.
Biodiversity offsets aim to counterbalance the residual impacts of development on species and ecosystems. Guidance documents explicitly recommend that biodiversity offset actions be located close to the location of impact because of higher potential for similar ecological conditions, but allowing greater spatial flexibility has been proposed. We examined the circumstances under which offsets distant from the impact location could be more likely to achieve no net loss or provide better ecological outcomes than offsets close to the impact area. We applied a graphical model for migratory shorebirds in the East Asian–Australasian Flyway as a case study to explore the problems that arise when incorporating spatial flexibility into offset planning. Spatially flexible offsets may alleviate impacts more effectively than local offsets; however, the risks involved can be substantial. For our case study, there were inadequate data to make robust conclusions about the effectiveness and equivalence of distant habitat-based offsets for migratory shorebirds. Decisions around offset placement should be driven by the potential to achieve equivalent ecological outcomes; however, when considering more distant offsets, there is a need to evaluate the likely increased risks alongside the potential benefits. Although spatially flexible offsets have the potential to provide more cost-effective biodiversity outcomes and more cobenefits, our case study showed the difficulty of demonstrating these benefits in practice and the potential risks that need to be considered to ensure effective offset placement.  相似文献   
22.
Environmental Science and Pollution Research - Over the last few decades, economic policy uncertainty (EPU) has surged across the globe. Furthermore, EPU affects economic activities, which may also...  相似文献   
23.
This study analyzes the effectiveness and efficiency of the two principal United Nations (UN) climate change mitigation finance mechanisms, the Clean Development Mechanism (CDM) and the Global Environment Facility (GEF). The realised abatement and costs of the two mechanisms in India and Brazil (using data from 28 GEF and 233 CDM project documents) are compared with theoretical marginal abatement cost curves, based on bottom-up technology studies. We find that both mechanisms have focused on negative and low-cost abatement potential but still leave substantial theoretical potential in this cost range untapped. CDM has more effectively harvested abatement potential of industrial gases and methane emissions, whereas GEF has more successfully targeted demand-side energy efficiency (EE) and transport emission reduction opportunities. CDM has excelled at capturing abatement potential in areas with a limited understanding of abatement, highlighting the shortcomings of theoretical estimates (such as Marginal Abatement Cost Curves) and the benefits of a market mechanism. In some sectors and technologies (particularly renewable energy), the two mechanisms overlapped, which suggests a need for better coordination in the future.  相似文献   
24.
In this paper, the deterioration of catalysts in small, four-stroke, spark-ignition engines is described. The laboratory testing performed followed a proven test method that mimics the lifetime of a small air-cooled utility engine operating under normal field conditions. The engines used were single-cylinder, 6.5-hp, side-valve engines. These engines have a nominal 125-hr lifetime. The effectiveness of the catalysts was determined by testing exhaust emissions before and after the catalyst to determine the catalyst's efficiency. This was done several times during the lifetime of the engines to determine the deterioration in the performance of the catalysts at lowering pollutant emissions. Additional testing was performed on the catalysts to determine wear patterns, contamination, and recoverable activity. The results indicate that considerable catalyst deterioration is occurring over the lifetime of the engine. The results reveal that soot buildup, poisons, and active surface loss appear to be the contributing factors to the deterioration. These results were determined after analyzing the exhaust emissions data, scanning electron microscope results analysis, and the impact of regeneration attempts. An ANOVA statistical analysis was performed, and it was determined that the emissions are also impacted, to some degree, by time and the engine itself.  相似文献   
25.
Muckian L  Grant R  Doyle E  Clipson N 《Chemosphere》2007,68(8):1535-1541
Bacterial community structure was examined in polycyclic aromatic hydrocarbon (PAH) contaminated soil taken from a timber treatment facility in southern Ireland. Profiles of soil bacterial communities were generated using a molecular fingerprinting technique, terminal restriction fragment length polymorphism (TRFLP), and results were interpreted using sophisticated multivariate statistical analysis. Findings suggested that there was a correlation between PAH structure and bacterial community composition. Initial characterisation of soil from the timber treatment facility indicated that PAH contamination was unevenly distributed across the site. Bacterial community composition was correlated with the type of PAH present, with microbial community structure associated with soil contaminated with two-ringed PAHs only being distinctly different to communities in soils contaminated with multi-component PAH mixtures. Typically the number of bacterial ribotypes detected in samples did not appear to be adversely affected by the level of contamination.  相似文献   
26.
Changes in land use and extreme rainfall trends can lead to increased flood vulnerability in many parts of the world, especially for urbanized watersheds. This study investigates the performance of existing stormwater management strategies for the Upper Yahara watershed in Dane County, WI to determine whether they are adequate to protect urban and suburban development from an extreme rainfall. Using extreme storm transposition, we model the performance of the stormwater infiltration practices required for new development under current county ordinances. We find during extreme rainfall the volume of post‐development runoff from impervious surfaces from a typical site would increase by over 55% over pre‐development conditions. We recommend the ordinance be strengthened to reduce vulnerability to flooding from future urban expansion and the likely increase in the magnitude and frequency of extreme storms.  相似文献   
27.
Corals and coral-associated species are highly vulnerable to the emerging effects of global climate change. The widespread degradation of coral reefs, which will be accelerated by climate change, jeopardizes the goods and services that tropical nations derive from reef ecosystems. However, climate change impacts to reef social–ecological systems can also be bi-directional. For example, some climate impacts, such as storms and sea level rise, can directly impact societies, with repercussions for how they interact with the environment. This study identifies the multiple impact pathways within coral reef social–ecological systems arising from four key climatic drivers: increased sea surface temperature, severe tropical storms, sea level rise and ocean acidification. We develop a novel framework for investigating climate change impacts in social–ecological systems, which helps to highlight the diverse impacts that must be considered in order to develop a more complete understanding of the impacts of climate change, as well as developing appropriate management actions to mitigate climate change impacts on coral reef and people.  相似文献   
28.
Halobenzoquinones(HBQs) are emerging disinfection byproducts(DBPs) with a widespread presence in drinking water that exhibit much higher cytotoxicity than regulated DBPs. However, the developmental neurotoxicity of HBQs has not been studied in vivo. In this work, we studied the neurotoxicity of HBQs on zebrafish embryos, after exposure to varying concentrations(0-8 μmol/L) of three HBQs, 2,5-dichloro-1,4-benzoquinone(2,5-DCBQ), 2,6-dichloro-1,4-benzoquinone(2,6-DCBQ), and 2,5-dibromo-1,4-benzoqu...  相似文献   
29.
Abstract

A sudden increase in serum creatinine after paraquat intoxication has been reported in several clinical studies. However, this dramatic change of creatinine may be possibly due to an interconversion of creatine-creatinine in relation to paraquat toxicity. In order to investigate the creatine-creatinine relationship, a liquid chromatography tandem mass spectrometry in combination with electrospray ionization was developed and validated for simultaneous determination of creatine and creatinine in the serum. The chromatographic separation was achieved on a Gemini® C6-Phenyl column with a gradient elution consisting of 0.1% formic acid in ultrapure water and methanol as the mobile phase. The method yielded suitable levels of specificity and selectivity, and calibration curves of creatine and creatinine in serum were linear over the concentration range of 0.5–200?µg mL?1. The limit of quantification of both compounds was 0.5?µg mL?1, and the method was accurate within the recovery range of 96.23–102.75%, indicating the robustness of the method. The method was successfully applied to toxicological samples from paraquat-intoxicated patients, and the concentrations of creatine and creatinine were quantified. High creatine concentrations in serum samples were observed which may lead to high serum creatinine despite normal kidney function as creatine is converted to creatinine in proportion to its concentration.  相似文献   
30.
Conservation discourses tend to portray invasive species as biological entities temporally connected to colonial timelines, using terms such as “alien”, “colonizing”, “colonial”, and “native”. This focus on a colonial timeline emerges from scientific publications within conservation biology and invasion ecology and is enacted through invasive species management by state and NGO actors. Colonialism is influential for indigenous nations in myriad ways, but in what ways do indigenous understandings of invasive species engage with colonialism? We conducted ethnographic research with indigenous Anishnaabe communities to learn about the ways Anishnaabe people conceptualize invasive species as a phenomenon in the world and were gifted with three primary insights. First, Anishnaabe regard plants, like all beings, as persons that assemble into nations more so than “species”. The arrival of new plant nations is viewed by some Anishnaabe as a natural form of migration. The second insight highlights the importance of actively discovering the purpose of new species, sometimes with the assistance of animal teachers. Lastly, while Anishnaabe describe invasive species as phenomenologically entangled with colonialism, the multiple ways Anishnaabe people think about invasive species provide alternatives to native–non-native binaries that dominate much of the scientific discourse.  相似文献   
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