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121.
Siyu Qin Rachel E. Golden Kroner Carly Cook Anteneh T. Tesfaw Rowan Braybrook Carlos Manuel Rodriguez Claire Poelking Michael B. Mascia 《Conservation biology》2019,33(6):1275-1285
Protected areas (PAs) are expected to conserve nature and provide ecosystem services in perpetuity, yet widespread protected area downgrading, downsizing, and degazettement (PADDD) may compromise these objectives. Even iconic protected areas are vulnerable to PADDD, although these PADDD events are often unrecognized. We identified 23 enacted and proposed PADDD events within World Natural Heritage Sites and examined the history, context, and consequences of PADDD events in 4 iconic PAs (Yosemite National Park, Arabian Oryx Sanctuary, Yasuní National Park, and Virunga National Park). Based on insights from published research and international workshops, these 4 cases revealed the diverse pressures brought on by competing interests to develop or exploit natural landscapes and the variety of mechanisms that enables PADDD. Knowledge gaps exist in understanding of the conditions through which development pressures translate to PADDD events and their impacts, partially due to a lack of comprehensive PADDD records. Future research priorities should include comprehensive regional and country-level profiles and analysis of risks, impacts, and contextual factors related to PADDD. Policy options to better govern PADDD include improving tracking and reporting of PADDD events, establishing transparent PADDD policy processes, coordinating among legal frameworks, and mitigating negative impacts of PADDD. To support PADDD research and policy reforms, enhanced human and financial capacities are needed to train local researchers and to host publicly accessible data. As the conservation community considers the achievements of Aichi Target 11 and moves toward new biodiversity targets beyond 2020, researchers, practitioners, and policy makers need to work together to better track, assess, and govern PADDD globally. 相似文献
122.
Food and Environmental Virology - Hepatitis A virus (HAV) was detected in frozen strawberries which had been implicated in a large outbreak of hepatitis A in 1997. The sample was analysed after... 相似文献
123.
Cook R Isakov V Touma JS Benjey W Thurman J Kinnee E Ensley D 《Journal of the Air & Waste Management Association (1995)》2008,58(3):451-461
A large body of literature published in recent years suggests increased health risk due to exposure of people to air pollution in close proximity to roadways. As a result, there is a need to more accurately represent the spatial concentration gradients near roadways to develop mitigation strategies. In this paper, we present a practical, readily adaptable methodology, using a "bottom-up" approach to develop a detailed highway vehicle emission inventory that includes emissions for individual road links. This methodology also takes advantage of geographic information system (GIS) software to improve the spatial accuracy of the activity information obtained from a Travel Demand Model. In addition, we present an air quality modeling application of this methodology in New Haven, CT. This application uses a hybrid modeling approach, in which a regional grid-based model is used to characterize average local ambient concentrations, and a Gaussian dispersion model is used to provide texture within the modeling domain because of spatial gradients associated with highway vehicle emissions and other local sources. Modeling results show substantial heterogeneity of pollutant concentrations within the modeling domain and strong spatial gradients associated with roadways, particularly for pollutants dominated by direct emissions. 相似文献
124.
Rich W. Baldauf Pete Gabele William Crews Richard Snow J. Rich Cook 《Journal of the Air & Waste Management Association (1995)》2013,63(9):1263-1268
Abstract The U.S. Environmental Protection Agency (EPA) implemented a program to identify tailpipe emissions of criteria and air-toxic contaminants from in-use, light-duty low-emission vehicles (LEVs). EPA recruited 25 LEVs in 2002 and measured emissions on a chassis dynamometer using the cold-start urban dynamometer driving schedule of the Federal Test Procedure. The emissions measured included regulated pollutants, particulate matter, speciated hydrocarbon compounds, and carbonyl compounds. The results provided a comparison of emissions from real-world LEVs with emission standards for criteria and air-toxic compounds. Emission measurements indicated that a portion of the in-use fleet tested exceeded standards for the criteria gases. Real-time regulated and speciated hydrocarbon measurements demonstrated that the majority of emissions occurred during the initial phases of the cold-start portion of the urban dynamometer driving schedule. Overall, the study provided updated emission factor data for real-world, in-use operation of LEVs for improved emissions modeling and mobile source inventory development. 相似文献
125.
This work shows the applicability of two-dimensional (2D) (1)H-(13)C heteronuclear correlation (HETCOR) nuclear magnetic resonance (NMR) spectroscopy to the characterization of whole soils. A combination of different mixing times and cross polarization (CP) methods, namely Lee-Goldberg (LG)-CP and Ramp-CP are shown to afford, for the first time, intra- and inter- molecular connectivities, allowing for molecular assemblage information to be obtained on a whole soil. Our results show that, for the brackish marsh histosol under study, two isolated domains could be detected. The first domain consists of O-alkyl and aromatic moieties (lignocellulose material), while the second domain is comprised of alkyl type moieties (cuticular material). The role of these domains is discussed in terms of hydrophobic organic compound sorption within soil organic matter (SOM), including the possible effects of wetting and drying cycles. 相似文献
126.
Marcus IM Bolster CH Cook KL Opot SR Walker SL 《Journal of environmental monitoring : JEM》2012,14(3):984-991
The aim of this investigation is to determine the effect that growth solution has on the cell surface properties and transport behavior of eleven Escherichia coli isolates through saturated porous media. The two growth solutions used were a standard laboratory growth medium (LB) and a dairy manure extract solution. In general, cells grown in manure extract were more hydrophobic, had a more negative zeta potential, had lower amounts of surface macromolecules, and had lower attachment efficiencies than isolates grown in LB. An inverse relationship between the natural log of zeta potential and the attachment efficiency of the isolates for the cells grown in LB media was the only statistically significant correlation observed between transport behavior and cell characteristics of the isolates. This study shows the need to consider growth conditions when studying bacteria to better mimic the environmental stresses that bacteria undergo in the natural environment. This approach could lead to a better understanding of the behavior of manure-derived bacteria in aquatic and terrestrial environments. 相似文献
127.
Geraint A. Tarling Jennifer J. Freer Neil S. Banas Anna Belcher Mayleen Blackwell Claudia Castellani Kathryn B. Cook Finlo R. Cottier Malin Daase Magnus L. Johnson Kim S. Last Penelope K. Lindeque Daniel J. Mayor Elaine Mitchell Helen E. Parry Douglas C. Speirs Gabriele Stowasser Marianne Wootton 《Ambio》2022,51(2):333
The changing Arctic environment is affecting zooplankton that support its abundant wildlife. We examined how these changes are influencing a key zooplankton species, Calanus finmarchicus, principally found in the North Atlantic but expatriated to the Arctic. Close to the ice-edge in the Fram Strait, we identified areas that, since the 1980s, are increasingly favourable to C. finmarchicus. Field-sampling revealed part of the population there to be capable of amassing enough reserves to overwinter. Early developmental stages were also present in early summer, suggesting successful local recruitment. This extension to suitable C. finmarchicus habitat is most likely facilitated by the long-term retreat of the ice-edge, allowing phytoplankton to bloom earlier and for longer and through higher temperatures increasing copepod developmental rates. The increased capacity for this species to complete its life-cycle and prosper in the Fram Strait can change community structure, with large consequences to regional food-webs.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01667-y. 相似文献
128.
Cook R Touma JS Fernandez A Brzezinski D Bailey C Scarbro C Thurman J Strum M Ensley D Baldauf R 《Journal of the Air & Waste Management Association (1995)》2007,57(12):1469-1479
Analyses of U.S. Environmental Protection Agency (EPA) certification data, California Air Resources Board surveillance testing data, and EPA research testing data indicated that EPA's MOBILE6.2 emission factor model substantially underestimates emissions of gaseous air toxics occurring during vehicle starts at cold temperatures for light-duty vehicles and trucks meeting EPA Tier 1 and later standards. An unofficial version of the MOBILE6.2 model was created to account for these underestimates. When this unofficial version of the model was used to project emissions into the future, emissions increased by almost 100% by calendar year 2030, and estimated modeled ambient air toxics concentrations increased by 6-84%, depending on the pollutant. To address these elevated emissions, EPA recently finalized standards requiring reductions of emissions when engines start at cold temperatures. 相似文献
129.
Defining ecologically relevant scales for spatial protection with long‐term data on an endangered seabird and local prey availability
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Richard B. Sherley Philna Botha Les G. Underhill Peter G. Ryan Danie van Zyl Andrew C. Cockcroft Robert J.M. Crawford Bruce M. Dyer Timothée R. Cook 《Conservation biology》2017,31(6):1312-1321
Human activities are important drivers of marine ecosystem functioning. However, separating the synergistic effects of fishing and environmental variability on the prey base of nontarget predators is difficult, often because prey availability estimates on appropriate scales are lacking. Understanding how prey abundance at different spatial scales links to population change can help integrate the needs of nontarget predators into fisheries management by defining ecologically relevant areas for spatial protection. We investigated the local population response (number of breeders) of the Bank Cormorant (Phalacrocorax neglectus), a range‐restricted endangered seabird, to the availability of its prey, the heavily fished west coast rock lobster (Jasus lalandii). Using Bayesian state‐space modeled cormorant counts at 3 colonies, 22 years of fisheries‐independent data on local lobster abundance, and generalized additive modeling, we determined the spatial scale pertinent to these relationships in areas with different lobster availability. Cormorant numbers responded positively to lobster availability in the regions with intermediate and high abundance but not where regime shifts and fishing pressure had depleted lobster stocks. The relationships were strongest when lobsters 20–30 km offshore of the colony were considered, a distance greater than the Bank Cormorant's foraging range when breeding, and may have been influenced by prey availability for nonbreeding birds, prey switching, or prey ecology. Our results highlight the importance of considering the scale of ecological relationships in marine spatial planning and suggest that designing spatial protection around focal species can benefit marine predators across their full life cycle. We propose the precautionary implementation of small‐scale marine protected areas, followed by robust assessment and adaptive‐management, to confirm population‐level benefits for the cormorants, their prey, and the wider ecosystem, without negative impacts on local fisheries. 相似文献
130.
Quantifying the extent of protected‐area downgrading,downsizing, and degazettement in Australia
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Carly N. Cook Rebecca S. Valkan Michael B. Mascia Melodie A. McGeoch 《Conservation biology》2017,31(5):1039-1052
The use of total area protected as the predominant indicator of progress in building protected area (PA) networks is receiving growing criticism. Documenting the full dynamics of PA networks, both in terms of the gains and losses in protection, provides a much more informative approach to tracking progress. To this end, documentation of PA downgrading, downsizing, and degazettement (PADDD) has increased. Studies of PADDD events generally fail to place these losses in the context of gains in protection; therefore, they omit important elements of PA network dynamics. To address this limitation, we used a spatially explicit approach to identify every parcel of land added to and excised from the Australian terrestrial PA network and PAs that had their level of protection changed over 17 years (1997–2014). By quantifying changes in the spatial configuration of the PA network with time‐series data (spatial layers for nine separate time steps), ours is the first assessment of the dynamics (increases and decreases in area and level of protection) of a PA network and the first comprehensive assessment of PADDD in a developed country. We found that the Australian network was highly dynamic; there were 5233 changes in area or level of protection over 17 years. Against a background of enormous increases in area protected, we identified over 1500 PADDD events, which affected over one‐third of the network, which were largely the result of widespread downgrading of protection. We believe our approach provides a mechanism for robust tracking of trends in the world's PAs through the use of data from the World Database on Protected Areas. However, this will require greater transparency and improved data standards in reporting changes to PAs. 相似文献