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Climate change is increasingly affecting organisms and ecosystems. The amount of research and the number of articles in this field is overwhelming. However, single studies necessarily consider limited aspects. Hence, there is an increasing need for structuring the research approaches and findings in climate change research in order to direct future action in an efficient way towards research gaps and areas of uncertainty. Here, we review the current state of knowledge accumulated over the last 10 years (2003–2012) about impacts of climate change on species and ecosystems. Almost 1,200 articles of the scientific literature listed in the ISI Web of Science are analysed. We explore the geographical distribution of knowledge gain, the studied taxonomic groups, ecosystems and environmental parameters as well as the applied methods. Several knowledge gaps arise. Most of the first authors of the analysed articles are residents of North America, Australia or Europe. A similar pattern is found for the study areas. Vascular plants and therewith forests are the most studied taxonomic group and ecosystem. The use of models to estimate potential impacts of climate change is well established in climate change impact research and is continuously developing. However, there is a lack of empirical data derived from experimental climate change simulations. In a rapidly evolving research landscape, this review aims at providing an overview of the current patterns of knowledge distribution and research demands arising from knowledge gaps and biases. Our results should help to identify future research needs and priorities.  相似文献   
96.
This study compared three different disinfection processes(chlorination, E-beam, and ozone) and the efficacy of three oxidants(H2O2, S2O-8, and peroxymonosulfate(MPS)) in removing antibiotic resistant bacteria(ARB) and antibiotic resistance genes(ARGs) in a synthetic wastewater. More than30 mg/L of chlorine was needed to remove over 90% of ARB and ARG. For the E-beam method, only1 dose(kGy) was needed to remove ARB and ARG, and ozone could reduce ARB and ARG by more than 90% even at 3 mg/L ozone concentration. In the ozone process, CT values(concentration × time)were compared for ozone alone and combined with different catalysts based on the 2-log removal of ARB and ARG. Ozone treatment yielded a value of 31 and 33(mg·min)/L for ARB and ARGs respectively. On the other hand, ozone with persulfate yielded 15.9 and 18.5(mg·min)/L while ozone with monopersulfate yielded a value of 12 and 14.5(mg·min)/L. This implies that the addition of these catalysts significantly reduces the contact time to achieve a 2-log removal, thus enhancing the process in terms of its kinetics.  相似文献   
97.
Changes in forest and agricultural land management practices have the potential to increase carbon (C) storage by terrestrial systems, thus offsetting C emissions to the atmosphere from energy production. This study assesses that potential for three terrestrial management practices within the state of Virginia, USA: afforestation of marginal agricultural lands; afforestation of riparian agricultural lands; and changing tillage practices for row crops; each was evaluated on a statewide basis and for seven regions within the state. Lands eligible for each practice were identified, and the C storage potential of each practice on those lands was estimated through a modeling procedure that utilized land-resource characteristics represented in Geographic Information System databases. Marginal agricultural lands’ afforestation was found to have the greatest potential (1.4 Tg C yr−1, on average, over the first 20 years) if applied on all eligible lands, followed by riparian afforestation (0.2 Tg C yr−1 over 20 years) and tillage conversion (0.1 Tg C yr−1 over 14 years). The regions with the largest potentials are the Ridge and Valley of western Virginia (due to extensive areas of steep, shallow soils) and in the Mid-Atlantic Coastal Plain in eastern Virginia (wet soils). Although widespread and rapid implementation of the three modeled practices could be expected to offset only about 3.4% of Virginia’s energy-related CO2 emissions over the following 20 years (equivalent to about 8.5% of a Kyoto Treaty–based target), they could contribute to achievement of C-management goals if implemented along with other mitigation measures.  相似文献   
98.
The aim of the present study, is to identify strengths and weaknesses of the technical safety review process at a Swedish Nuclear Power Plant (NPP). In this context, the function of safety reviews are understood as expert judgements on proposals for design modifications1 and redesign of technical systems (i.e. commercial nuclear reactors), supported by formalised safety review processes. The chosen methodology is using two complementary methods: interviews of personnel performing safety reviews, and analysis of safety review reports from 2005 to 2009.The study shows that personal integrity is a trademark of the review staff and there are sufficient support systems to ensure high quality. The partition between primary and independent review is positive, having different focus and staff with different skills and perspectives making the reviews, which implies supplementary roles. The process contributes to “getting the right things done the right way”. The study also shows that though efficient communication, feedback, processes for continuous improvement, and “learning organizations” are well known success factors in academia, it is not that simple to implement and accomplish in real life.It is argued that future applications of safety review processes should focus more on communicating and clarifying the process and its adherent requirements, and improve the feedback system within the process.  相似文献   
99.
A limnological survey was conducted of Little Black Lake, MI, and its tributaries during summer 2007. This small, shallow lake is located in a rapidly developing area of west Michigan. As such, our analytical approach and recommendations can serve as a model for other similar systems threatened by urbanization. Soluble reactive phosphorus and nitrate concentrations in both the inflows to (during baseflow) and Little Black Lake itself were low (??0.007 and ??270 mg/L, respectively). Nutrient concentrations increased during stormflow conditions, although the magnitude of the increase depended on the nutrient and sampling location. Macrophyte growth was extensive throughout most parts of the lake, with Chara and Potamogeton spp. present in most sites; based on the coefficient of conservatism, plant composition was indicative of good water quality conditions. Chlorophyll a concentration averaged 1.7 ??g/L in Little Black Lake, with cryptophytes and cyanobacteria being the most dominant members (by biovolume) of the phytoplankton community. The fish community in Little Black Lake was dominated by bluegill (Lepomis macrochirus) and pumpkinseed (L. gibbosus), with no invasive species observed. Overall, abiotic and biotic conditions indicate that Little Black Lake is in good ecological health despite increasing pressures of urbanization in its watershed. To maintain this status, it is recommended that the local municipalities develop a comprehensive watershed management plan and implement best management practices to limit nonpoint source pollutant loading to Little Black Lake.  相似文献   
100.
ABSTRACT: A number of criteria can be used in the selection of an area for the irrigation disposal of secondary treated waste water. The inherent capacity of the surface soil to retain, or at least detain, the various nutrient ions passing through the profile in the percolating waters becomes the prime consideration in regions with shallow water tables or in Karst areas such as the Missouri Ozarks where the risk of ground water supply contamination is high. A comprehensive study of the nutrient renovation potential of several soils was undertaken at a proposed effluent irrigation site along the Ozark National Scenic Riverways in south central Missouri. The surface soil hydrology was evaluated employing selected soil water parameters. Exchange equilibria studies determined the retention capacity for Ca and Mg while the concentrations of other selected ions were analyzed in the soil water to measure their retention time and net removal. The movement of a bromine tracer was monitored as an index of the renovation capacity of these soils for the more mobile anions such as nitrate. Neutron activation analysis proved to be a useful tool in the water quality analyses. All surface soil profiles demonstrated some degree of nutrient renovation for the various nutrients studied.  相似文献   
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