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231.
While many scientific assessments have been recommending general strategies for biodiversity conservation under climate change, translation of these recommendations into specific actions and practice has been limited. Focusing on two biomes, rainforest and wetlands in biodiverse South East Queensland, Australia, we demonstrate how general principles can be translated into specific actions for stakeholders and responsible agencies. We synthesize research that is contextualizing protection of refugia and habitat connectivity, establishing baseline data sets to detect change and developing strategic conservation planning scenarios to adjust reserve boundaries or situate new reserves. This has been achieved by coupling spatial information on biological assets (i.e. ecosystems and species) with future climate scenarios and process models to anticipate movement of critical habitats. Conservation planning software is also being used to prioritize investment to meet specific objectives. This approach is enabling us to identify at-risk biological assets, opportunities to ameliorate threats and obstacles to delivering regional adaptation actions. A larger total reserved area is needed, with proactive planning to capture areas further inland and along watercourses. Major obstacles include conflict between urbanization and priorities for habitat conservation and the need for greater levels of investment for monitoring programmes and to protect landward shifted wetlands on private land.  相似文献   
232.
Metal mobilization in soil by two structurally defined polyphenols   总被引:2,自引:0,他引:2  
Polyphenols including tannins comprise a large percentage of plant detritus such as leaf litter, and affect soil processes including metal dynamics. We tested the effects of tannins on soil metal mobilization by determining the binding stoichiometries of two model polyphenols to Al(III) and Fe(III) using micelle-mediated separation and inductively coupled plasma optical emission spectroscopy (ICP-OES). By fitting the data to the Langmuir model we found the higher molecular weight polyphenol (oenothein B) was able to bind more metal than the smaller polyphenol (epigallocatechin gallate, EGCg). For example, oenothein B bound 9.43 mol Fe mol?1, while EGCg bound 4.41 mol of Fe mol?1. Using the parameters from the binding model, we applied the Langmuir model for competitive binding to predict binding for mixtures of Al(III) and Fe(III). Using the parameters from the single metal experiments and information about polyphenol sorption to soils we built a model to predict metal mobilization from soils amended with polyphenols. We tested the model with three natural soils and found that it predicted mobilization of Fe and Al with r2 = 0.92 and r2 = 0.88, respectively. The amount of metal that was mobilized was directly proportional to the maximum amount of metal bound to the polyphenol. The secondary parameter in each model was the amount of weak organically chelated Fe or Al that was in the soil. This study provides the first compound-specific information about how natural polyphenols interact with metals in the environment. We propose a model that is applicable to developing phytochelation agents for metal detoxification, and we discuss how tannins may play a role in metal mobilization from soils.  相似文献   
233.
The bioaccumulation of lipophilic contaminants such as polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), and polybrominated diphenyl ethers (PBDEs) can result in a reduction in fitness and spawner quality in eels and may be a factor in Anguillid sp. population declines. Contaminant concentrations in eels have been studied extensively in Europe, but data for American eels are severely lacking. Concentrations of PCBs, OCPs, and PBDEs were determined in American eel from eastern Canada and New York, USA, along with European eel from Belgium. Principal component analysis revealed that eels captured in the St. Lawrence estuary were a mixture of upstream migrants from the St. Lawrence River watershed, and fish captured in local tributaries. Contaminant concentrations were dependent on origin, related to the local environment, and were lower than historic values. In Canada, concentrations of OCPs and PCBs in eel tissues were below the Canadian human consumption guidelines for contaminants in fish, indicating that the current risk to consumers is low. However, concentrations of PCBs, total DDT, and mirex in eels from L. Ontario and the upper St. Lawrence R. were above Great Lakes guidelines for the protection of piscivorous predators. Concentrations of penta-BDE homologs exceeded the Canadian guideline for environmental quality in over half of the eels in this study, but concentrations of the other homolog groups were below the guideline.  相似文献   
234.
Directly comparable data on the environmental and socio-economic impacts of alien species informs the effective prioritisation of their management. We used two frameworks, the Environmental Impact Classification for Alien Taxa (EICAT) and Socio-Economic Impact Classification for Alien Taxa (SEICAT), to create a unified dataset on the severity and type of impacts caused by alien leporids (rabbits and hares). Literature was reviewed to collate impact data, which was categorised following EICAT and SEICAT guidelines. We aimed to use these data to identify: (1) alien leporid species with severe impacts, (2) their impact mechanisms, (3) the native species and local communities vulnerable to impacts and (4) knowledge gaps. Native species from a range of taxonomic groups were affected by environmental impacts which tended to be more damaging than socio-economic impacts. Indirect environmental impacts were particularly damaging and underreported. No impact data were found for several alien leporid species.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01642-7.  相似文献   
235.
Polycyclic aromatic hydrocarbons (PAHs) and their health risks in surface soils (n?=?31) collected from coastal and estuarine areas of the northern Bohai and Yellow Seas (CEANBYS), China, were investigated. Total concentrations of PAHs ranged from 6.6?×?101 to 9.2?×?102?ng?g?1 dry weight, with an average of 3.1?×?102?ng?g?1 dw. The locations where greater concentrations of PAHs were observed were all near factories emitting black smoke or on the edge of the urban areas. These observations are consistent with concentrations of PAHs in soils being influenced by human activities, especially industrialization and urbanization. Concentrations of PAHs were significantly correlated with concentrations of organic carbon in soils. The patterns of relative concentrations and types of PAHs observed as well as knowledge of the potential sources were consistent with the primary sources of PAHs in soils of the CEANBYS being derived from the pyrolytic processes such as combustion of fossil fuel. The incremental lifetime cancer risks of exposing to PAHs for child, youth, and adult were 1.6?×?10?6, 1.2?×?10?6, and 1.9?×?10?6.  相似文献   
236.
Five marine cosmopolitan phytoplankton species namely; Calcidiscus leptoporus, Emiliania huxleyi, Phaeodactylum tricornutum, Chaetoceros neogracilis and Dunaliella tertiolecta were screened for emissions of selected VOCs using head space gas chromatography/mass spectrometry (HS-GC/MS) in single ion mode. The VOCs investigated included isoprene and various halogenated compounds. Among the different algae groups, the two diatoms Ch. neogracilis and P. tricornutum were the strongest emitters of methyl bromide (CH3Br), and Ch. neogracilis was the strongest emitter of isoprene. Furthermore, we present evidence that several chlorinated organic compounds, normally considered as anthropogenic, can be produced from marine phytoplankton (namely chloroform, dichloromethane, trichloroethylene, tetrachloroethylene, chlorobenzene and dichlorobenzene).  相似文献   
237.
ABSTRACT

An intercomparison study has been performed with six empirical ozone interpolation procedures to predict hourly concentrations in ambient air between monitoring stations. The objective of the study is to use monitoring network data to empirically identify an improved procedure to estimate ozone concentrations at subject exposure points. Four of the procedures in the study are currently used in human exposure models (nearest monitors daily mean and maximum, regression estimate used in the U.S. Environmental Protection Agency's (EPA) pNEM, and inverse distance weighting), and two are being evaluated for this purpose (kriging in space and kriging in space and time). The study focused on spatial estimation during June 1-June 5, 1996, with relatively high observed ozone levels over Houston, Texas. The study evaluated these procedures at three types of locations with monitors of varying proximity. Results from the empirical evaluation indicate that kriging in space and time provides excellent estimates of ozone concentrations within a monitoring network, while the more often used techniques failed to capture observed pollutant concentrations. Improved estimation of pollutant concentrations within the region, and thus at subject locations, should result in improved exposure modeling.  相似文献   
238.
Air trajectory and particle scattering data (bsp) for the period 1984-1989 are used to determine the relationship between atmospheric transport and visual air quality at the Grand Canyon National Park. Using cluster analysis, 72-hour back-trajectories arriving four times per day were grouped into distinct transport patterns. Northwesterly and southerly/southwesterly flow dominate in the winter and summer seasons, respectively. Comparisons of bsp values accompanying different transport patterns showed a clear relationship between air flow pathway and light scattering due to small particles during the non-summer months only. An index is defined which describes the percentage of annual trajectories belonging to specific transport routes delivering predominantly clear air to the GCNP.  相似文献   
239.
The fate and transport of antibiotics in natural water systems is controlled in part by interactions with nanometer (10−9 m) metal oxide particles. Experiments were performed by mixing solutions of ampicillin (AMP), a common, penicillin-class human and veterinary antibiotic, with 25 nm-TiO2 (anatase) nanoparticles at different pH conditions. Both sorption and degradation of AMP were observed in the AMP-nanoparticle solutions. For AMP concentrations from ∼3 μM to 2.9 mM the overall AMP removal from solution can be described by linear isotherms with removal coefficients (Kr) of 3028 (±267) L kg−1 at pH 2, 11,533 (±823) L kg−1 at pH 4, 12,712 (±672) L kg−1 at pH 6, and 1941 (±342) L kg−1 at pH 8. Mass spectral analysis of AMP solutions after removal of the solid nanoparticles yielded ions that indicate the presence of peniclloic acid, penilloic acid and related de-ammoniated by-products as possible compounds resulting from the degradation of AMP at the TiO2 surface.  相似文献   
240.
INTRODUCTION: Flowing of the acid mine drainage may contaminate the adjacent water bodies causing substantial changes in the aquatic ecosystem. This aspect is the most relevant problem in the southern of Santa Catarina once the contaminated areas are inserted in the watershed of the Araranguá, Urussanga, and Tubar?o rivers, increasing the need for recovery studies. These areas are between Criciúma, I?ara, Urussanga, Siderópolis, Lauro Müller, Orleans, and Alfredo Wagner towns where a conservation unit exist called the Environmental Preservation Area of Baleia Franca. Aiming to compare the kinetics of the ash derived from burning coal and to neutralize acid mine drainage, different neutralizer, limestone, fly, and bottom ash, was mounted on a pilot scale experiment. DISCUSSION: The transport parameters showed the same order of infiltration and dispersion: fly ash < bottom ash < limestone. The order of measured alkalinity was: limestone < fly ash < bottom ash, with pH values of 9.34, 12.07, and 12.25, respectively. The limestone kinetics of acidic drainage neutralization was first order with reaction rate constant k?=?0.0963 min(-1), bottom ash was 3/4 with k?=?0.0723 mol(1/4) L(-1/4) min(-1), and the fly ash had higher order kinetics, 4/3, with reaction rate constant k?=?27.122 L(1/3) mol(-1/3) min(-1). However, by mathematical modeling, it was found that due to a combination of transport and kinetics, only limestone treatment reached a pH above 6 within 5 years, corresponding to the ideal as planned.  相似文献   
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