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141.
The Adaptation for Conservation Targets (ACT) Framework: A Tool for Incorporating Climate Change into Natural Resource Management 总被引:1,自引:0,他引:1
MS Cross ES Zavaleta D Bachelet ML Brooks CA Enquist E Fleishman LJ Graumlich CR Groves L Hannah L Hansen G Hayward M Koopman JJ Lawler J Malcolm J Nordgren B Petersen EL Rowland D Scott SL Shafer MR Shaw GM Tabor 《Environmental management》2012,50(3):341-351
As natural resource management agencies and conservation organizations seek guidance on responding to climate change, myriad potential actions and strategies have been proposed for increasing the long-term viability of some attributes of natural systems. Managers need practical tools for selecting among these actions and strategies to develop a tailored management approach for specific targets at a given location. We developed and present one such tool, the participatory Adaptation for Conservation Targets (ACT) framework, which considers the effects of climate change in the development of management actions for particular species, ecosystems and ecological functions. Our framework is based on the premise that effective adaptation of management to climate change can rely on local knowledge of an ecosystem and does not necessarily require detailed projections of climate change or its effects. We illustrate the ACT framework by applying it to an ecological function in the Greater Yellowstone Ecosystem (Montana, Wyoming, and Idaho, USA)-water flows in the upper Yellowstone River. We suggest that the ACT framework is a practical tool for initiating adaptation planning, and for generating and communicating specific management interventions given an increasingly altered, yet uncertain, climate. 相似文献
142.
Esther Coz Begoña Artíñano Lisa M. Clark Mark Hernandez Allen L. Robinson Gary S. Casuccio Traci L. Lersch Spyros N. Pandis 《Atmospheric environment (Oxford, England : 1994)》2010,44(32):3952-3962
Scanning electron microscopy coupled to energy-dispersive x-ray spectroscopy (SEM/EDX) was used to quantify individual bioparticles in PM2.5 samples collected during the Pittsburgh Air Quality Study. Microscopy-based estimates of primary biogenic organic aerosol (PBOA) mass were compared to carbohydrate mass associated with PM2.5. Carbohydrates show substantial seasonal variations, with higher concentrations in the spring and the fall. During the summer, carbohydrates were about 30% of the estimated PBOA concentrations, but in the winter carbohydrate concentrations often greatly exceeded the PBOA mass estimate. Spores and insect detritus were the most abundant PBOA types in the summer samples, while winter samples were comprised predominantly of a mixture of microorganisms, insect and vegetative detritus. During the summer PBOA contributed on average 6.9 ± 5.4% by mass of the PM2.5 versus 3.3 ± 1.4% of the PM2.5 mass during the winter. 相似文献
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144.
Lisa M. Fraley Andrew J. Miller Claire Welty 《Journal of the American Water Resources Association》2009,45(3):748-766
Abstract: A study was conducted between September 2003 and September 2006 to obtain baseline sediment inventories and monitor sediment transport and storage along a 3.7 km length of the channel of Valley Creek within Valley Forge National Historical Park, Pennsylvania. Valley Creek is a tributary of the Schuylkill River and drains an urbanizing 60.6 km2 watershed that currently has 18% impervious land cover. Numerous field methods were employed to measure the suspended sediment yield, longitudinal profile, cross‐sections, banklines, and particle size distribution of the streambed. Suspended sediment yield for the watershed was measured at a USGS gage located just upstream of the park boundary between July 2004 and July 2005, the period corresponding to field surveys of bank erosion and channel change. The estimated suspended sediment yield of 95.7 t/km2/year is representative of a year with unusually high discharge, including a storm event that produced a peak of 78 m3/s, the second highest discharge on record for the USGS gage. Based on the median annual streamflow for the 24 years of record at the USGS gage from 1983 to 2006, the median annual sediment yield is estimated to be closer to 34 t/km2/year, considerably lower than median and mean values for other sites within the region. The mass of silt, clay, and fine sand derived from bank erosion along the 3.7 km study reach during the field survey period accounts for an estimated 2,340 t, equivalent to about 43% of the suspended sediment load. The mass of fine sediment stored in the bed along the study reach was estimated at 1,500 t, with about 330 t of net erosion during the study period. Although bank erosion appears to be a potentially dominant source of sediment by comparison with annual suspended sediment load, bed sediment storage and potential for remobilization is of the same order of magnitude as the mass of sediment derived from bank erosion. 相似文献
145.
146.
Lisa M. Smith Janet A. Nestlerode Linda C. Harwell Pete Bourgeois 《Environmental monitoring and assessment》2010,171(1-4):611-620
The availability of wetlands and shallow water habitats significantly influences Gulf of Mexico (GOM) penaeid shrimp fishery productivity. However, the GOM region has the highest rate of wetland loss in the USA. Protection and management of these vital GOM habitats are critical to sustainable shrimp fisheries. Brown shrimp (Farfantepenaeus aztecus) are a major component of GOM fisheries. We present an approach for estimating the areal extent of suitable habitat for post-larval and juvenile brown shrimp in Mobile Bay, Alabama, using an existing habitat suitability index model for the northern GOM calculated from probabilistic survey of water quality and sediment data, land cover data, and submerged aquatic vegetation coverages. This estuarine scale approach is intended to support targeted protection and restoration of these habitats. These analyses indicate that approximately 60% of the area of Mobile Bay is categorized as suitable to near optimal for post-larval and juvenile shrimp and 38% of the area is marginally to minimally suitable. We identify potential units within Mobile Bay for targeted restoration to improve habitat suitability. 相似文献
147.
Anne Ostermann Jing Gao Gerhard Welp Jan Siemens Marco Roelcke Lisa Heimann Rolf Nieder Qiaoyun Xue Xianyong Lin Alexandra Sandhage-Hofmann Wulf Amelung 《Environmental monitoring and assessment》2014,186(11):7693-7707
In regions with high livestock densities, the usage of antibiotics and metals for veterinary purposes or as growth promoters poses a risk in manured soils. We investigated to which degree the concentrations and depth distributions of Cu, Zn, Cr and As could be used as a tracer to discover contaminations with sulfonamides, tetracyclines and fluoroquinolones. Besides, we estimated the potential vertical translocation of antibiotics and compared the results to measured data. In the peri-urban region of Beijing, China, soil was sampled from agricultural fields and a dry riverbed contaminated by organic waste disposal. The antibiotic concentrations reached 110 μg kg?1 sulfamethazine, 111 μg kg?1 chlortetracycline and 62 μg kg?1 enrofloxacin in the topsoil of agricultural fields. Intriguingly, total concentrations of Cu, Zn, Cr and As were smaller than 65, 130, 36 and 10 mg kg?1 in surface soil, respectively, therewith fulfilling Chinese quality standards. Correlations between sulfamethazine concentrations and Cu or Zn suggest that in regions with high manure applications, one might use the frequently existing monitoring data for metals to identify potential pollution hotspots for antibiotics in topsoils. In the subsoils, we found sulfamethazine down to ≥2 m depth on agricultural sites and down to ≥4 m depth in the riverbed. As no translocation of metals was observed, subsoil antibiotic contamination could not be predicted from metal data. Nevertheless, sulfonamide stocks in the subsoil could be estimated with an accuracy of 35–200 % from fertilisation data and potential leaching rates. While this may not be sufficient for precise prediction of antibiotic exposure, it may very well be useful for the pre-identification of risk hotspots for subsequent in-depth assessment studies. 相似文献
148.
Larry D. Johnson M. Rodney Midgett Ruby H. James Michael M. Thomason M. Lisa Manier 《Journal of the Air & Waste Management Association (1995)》2013,63(5):709-713
The body of information presented in this paper is directed to those individuals concerned with developing or implementing screening strategies for characterizing organic emissions from incinerators and other combustion sources. The need to characterize hazardous waste incinerator emissions for multiple organic compounds has been steadily increasing for several years. The regulatory approach makes use of a type of indicator compound procedure that concentrates on principal organic hazardous constituents (POHCs). In addition to continuing interest in POHCs, interest has been growing in the types and concentrations of products of incomplete combustion (PICs). Sampling and analysis methods have been developed previously for approximately 225 of the more important POHCs and PICs. These methods may be used as components of a cost-effective screening protocol aimed at maximum characterization of emissions, whether the project budget is large or small. This paper contains a discussion of fundamental principles of several kinds of screening strategies and recommends an approach suitable for incinerators and other combustion sources. The concept of a risk-driven analysis strategy is introduced and illustrated with a simplified example. 相似文献
149.
This research investigates the environmental behavior of two widely prescribed cholesterol-lowering statin drugs that are expected to be present at significant concentrations in wastewater influents, namely: atorvastatin and simvastatin. Batch biodegradation experiments suggest that both statins are well degraded during secondary treatment, and removal rates exhibit a substrate-enhancement model reflecting elements of both first-order behavior and cometabolism. Resulting biodegradation parameters are used in conjunction with literature sorption parameters to construct a mass-balance model of statin concentrations during conventional treatment. Model results exhibit excellent accuracy compared to measurements from a medium-sized WWTP in the Southeastern USA. Influent concentrations of 1.56 μg L(-1) and 1.23 μg L(-1) were measured for atorvastatin and simvastatin. Results also suggest that 85-90% of each drug is removed during conventional treatment, with sorption accounting for less than 10% of overall removal. Expected effluent concentrations are orders of magnitude less than previously reported ecotoxicity thresholds for both drugs. Overall, results suggest statin active ingredients do not pose a significant environmental threat. It is recommended that future work characterize the fate of statin metabolites and that the same mass-balance modeling approach be used to assess other highly-prescribed pharmaceutical drugs. 相似文献
150.
Planetary Stewardship in an Urbanizing World: Beyond City Limits 总被引:1,自引:0,他引:1
Sybil P. Seitzinger Uno Svedin Carole L. Crumley Will Steffen Saiful Arif Abdullah Christine Alfsen Wendy J. Broadgate Frank Biermann Ninad R. Bondre John A. Dearing Lisa Deutsch Shobhakar Dhakal Thomas Elmqvist Neda Farahbakhshazad Owen Gaffney Helmut Haberl Sandra Lavorel Cheikh Mbow Anthony J. McMichael Joao M. F. deMorais Per Olsson Patricia Fernanda Pinho Karen C. Seto Paul Sinclair Mark Stafford Smith Lorraine Sugar 《Ambio》2012,41(8):787-794
Cities are rapidly increasing in importance as a major factor shaping the Earth system, and therefore, must take corresponding responsibility. With currently over half the world’s population, cities are supported by resources originating from primarily rural regions often located around the world far distant from the urban loci of use. The sustainability of a city can no longer be considered in isolation from the sustainability of human and natural resources it uses from proximal or distant regions, or the combined resource use and impacts of cities globally. The world’s multiple and complex environmental and social challenges require interconnected solutions and coordinated governance approaches to planetary stewardship. We suggest that a key component of planetary stewardship is a global system of cities that develop sustainable processes and policies in concert with its non-urban areas. The potential for cities to cooperate as a system and with rural connectivity could increase their capacity to effect change and foster stewardship at the planetary scale and also increase their resource security. 相似文献