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541.
Ecological risk assessment of arsenic and metals in sediments of coastal areas of northern Bohai and Yellow Seas, China 总被引:3,自引:0,他引:3
Distributions of arsenic and metals in surface sediments collected from the coastal and estuarine areas of the northern Bohai and Yellow Seas, China, were investigated. An ecological risk assessment of arsenic and metals in the sediments was evaluated by three approaches: the Sediment Quality Guidelines (SQGs) of the United States Environmental Protection Agency (USEPA), the degree of contamination, and two sets of SQGs indices. Sediments from the estuaries of the Wuli and Yalu Rivers contained some of the greatest concentrations of arsenic, cadmium, copper, mercury, lead, and zinc. Median concentrations of cadmium and mean concentrations of lead and zinc were greater than background concentrations determined for the areas. All sediments were considered to be heavily polluted by arsenic, but moderately polluted by chromium, lead, and cadmium. Current concentrations of arsenic and metals are unlikely to be acutely toxic, but chronic exposures would be expected to cause adverse effects on benthic invertebrates at 31.4% of the sites. 相似文献
542.
Rob J. Lewis Francesco de Bello Jonathan A. Bennett Pavel Fibich Genevieve E. Finerty Lars Götzenberger Inga Hiiesalu Liis Kasari Jan Lepš Maria Májeková Ondřej Mudrák Kersti Riibak Argo Ronk Terezie Rychtecká Alena Vitová Meelis Pärtel 《Conservation biology》2017,31(1):40-47
Linking diversity to biological processes is central for developing informed and effective conservation decisions. Unfortunately, observable patterns provide only a proportion of the information necessary for fully understanding the mechanisms and processes acting on a particular population or community. We suggest conservation managers use the often overlooked information relative to species absences and pay particular attention to dark diversity (i.e., a set of species that are absent from a site but that could disperse to and establish there, in other words, the absent portion of a habitat‐specific species pool). Together with existing ecological metrics, concepts, and conservation tools, dark diversity can be used to complement and further develop conservation prioritization and management decisions through an understanding of biodiversity relativized by its potential (i.e., its species pool). Furthermore, through a detailed understanding of the population, community, and functional dark diversity, the restoration potential of degraded habitats can be more rigorously assessed and so to the likelihood of successful species invasions. We suggest the application of the dark diversity concept is currently an underappreciated source of information that is valuable for conservation applications ranging from macroscale conservation prioritization to more locally scaled restoration ecology and the management of invasive species. 相似文献
543.
Katharine R. E. Sims Jonathan R. Thompson Spencer R. Meyer Christoph Nolte Joshua S. Plisinski 《Conservation biology》2019,33(5):1035-1044
Land protection, whether public or private, is often controversial at the local level because residents worry about lost economic activity. We used panel data and a quasi-experimental impact-evaluation approach to determine how key economic indicators were related to the percentage of land protected. Specifically, we estimated the impacts of public and private land protection based on local area employment and housing permits data from 5 periods spanning 1990–2015 for all major towns and cities in New England. To generate rigorous impact estimates, we modeled economic outcomes as a function of the percentage of land protected in the prior period, conditional on town fixed effects, metro-region trends, and controls for period and neighboring protection. Contrary to narratives that conservation depresses economic growth, land protection was associated with a modest increase in the number of people employed and in the labor force and did not affect new housing permits, population, or median income. Public and private protection led to different patterns of positive employment impacts at distances close to and far from cities, indicating the importance of investing in both types of land protection to increase local opportunities. The greatest magnitude of employment impacts was due to protection in more rural areas, where opportunities for both visitation and amenity-related economic growth may be greatest. Overall, we provide novel evidence that land protection can be compatible with local economic growth and illustrate a method that can be broadly applied to assess the net economic impacts of protection. 相似文献
544.
Naomi L. Indigo Chris J. Jolly Ella Kelly James Smith Jonathan K. Webb Ben L. Phillips 《Conservation biology》2021,35(4):1245-1255
Cultural adaptation is one means by which conservationists may help populations adapt to threats. A learned behavior may protect an individual from a threat, and the behavior can be transmitted horizontally (within generations) and vertically (between generations), rapidly conferring population-level protection. Although possible in theory, it remains unclear whether such manipulations work in a conservation setting; what conditions are required for them to work; and how they might affect the evolutionary process. We examined models in which a population can adapt through both genetic and cultural mechanisms. Our work was motivated by the invasion of highly toxic cane toads (Rhinella marina) across northern Australia and the resultant declines of endangered northern quolls (Dasyurus hallucatus), which attack and are fatally poisoned by the toxic toads. We examined whether a novel management strategy in which wild quolls are trained to avoid toads can reduce extinction probability. We used a simulation model tailored to quoll life history. Within simulations, individuals were trained and a continuous evolving trait determined innate tendency to attack toads. We applied this model in a population viability setting. The strategy reduced extinction probability only when heritability of innate aversion was low (<20%) and when trained mothers trained >70% of their young to avoid toads. When these conditions were met, genetic adaptation was slower, but rapid cultural adaptation kept the population extant while genetic adaptation was completed. To gain insight into the evolutionary dynamics (in which we saw a transitory peak in cultural adaptation over time), we also developed a simple analytical model of evolutionary dynamics. This model showed that the strength of natural selection declined as the cultural transmission rate increased and that adaptation proceeded only when the rate of cultural transmission was below a critical value determined by the relative levels of protection conferred by genetic versus cultural mechanisms. Together, our models showed that cultural adaptation can play a powerful role in preventing extinction, but that rates of cultural transmission need to be high for this to occur. 相似文献
545.
Jonathan Salerno Karen Bailey Andrea E. Gaughan Forrest R. Stevens Tom Hilton Lin Cassidy Michael D. Drake Narcisa G. Pricope Joel Hartter 《Conservation biology》2020,34(4):891-902
Interactions between humans and wildlife resulting in negative impacts are among the most pressing conservation challenges globally. In regions of smallholder livestock and crop production, interactions with wildlife can compromise human well-being and motivate negative sentiment and retaliation toward wildlife, undermining conservation goals. Although impacts may be unavoidable when human and wildlife land use overlap, scant large-scale human data exist quantifying the direct costs of wildlife to livelihoods. In a landscape of global importance for wildlife conservation in southern Africa, we quantified costs for people living with wildlife through a fundamental measure of human well-being, food security, and we tested whether existing livelihood strategies buffer certain households against crop depredation by wildlife, predominantly elephants. To do this, we estimated Bayesian multilevel statistical models based on multicounty household data (n = 711) and interpreted model results in the context of spatial data from participatory land-use mapping. Reported crop depredation by wildlife was widespread. Over half of the sample households were affected and household food security was reduced significantly (odds ratio 0.37 [0.22, 0.63]). The most food insecure households relied on gathered food sources and welfare programs. In the event of crop depredation by wildlife, these 2 livelihood sources buffered or reduced harmful effects of depredation. The presence of buffering strategies suggests a targeted compensation strategy could benefit the region's most vulnerable people. Such strategies should be combined with dynamic and spatially explicit land-use planning that may reduce the frequency of negative human–wildlife impacts. Quantifying and mitigating the human costs from wildlife are necessary steps in working toward human–wildlife coexistence. 相似文献
546.
Relative importance of male and territory quality in pairing success of male rock ptarmigan (Lagopus mutus) 总被引:4,自引:0,他引:4
We studied pairing success in male rock ptarmigan (Lagopus mutus) in northern Alaska to learn whether males obtaining more females possessed phenotypic traits that influenced female choice
directly, whether these traits permitted males to obtain territories favored by females, or whether both processes occurred.
The number of females per male varied from zero to three. Several male and territory traits were significantly correlated
with number of females per male. We used multiple regression to obtain a single measure of male quality and a single measure
of territory quality. These measures of male and territory quality correlated with each other and with male pairing success.
We used path analysis to separate direct effects of male quality on pairing success from indirect effects due to high-quality
males obtaining high-quality territories. Both direct and indirect pathways had significant effects on pairing success, and
direct and indirect effects of male traits on pairing success were about equal. This study illustrates an analytical approach
for estimating the relative importance of direct and indirect causal relationships in natural systems.
Received: 13 January 1998 / Accepted after revision: 7 November 1998 相似文献
547.
A Suggestion for an Improved Vegetation Scheme for Local and Global Mapping and Monitoring 总被引:1,自引:0,他引:1
Jonathan M. Adams 《Environmental management》1999,23(1):1-13
The next stage in the process will be to obtain the views of as many people working in as many different fields as possible,
to see whether the proposed scheme suits their needs and how it should be modified. With a few modifications, such a scheme
could easily be appended to an existing land cover classification scheme, such as the FAO system, greatly increasing the usefulness
and accessability of the results of the landcover classification. 相似文献
548.
Jonathan Levinson 《环境质量管理》1999,8(3):93-104
Environmental Information Services, Inc. (EIS) publishes detailed reports and offers custom research related to the full spectrum of environmental issues facing corporations. This article highlights several key sections from EIS's new 1998 Electrical Equipment Industry Report. It details the environmental performance, policies, and expenditures of the largest companies in the electrical equipment industry. EIS industry reports contain data on five key performance criteria—toxic waste management, hazardous waste generation, penalties and enforcement actions, and spills. Here we examine one of those—penalties and enforcement actions—and the policies of the largest companies. 相似文献
549.
Jonathan Levinson 《环境质量管理》1999,8(4):79-91
Environmental Information Services (EIS) publishes detailed reports and offers custom research related to the full spectrum of environmental issues facing corporations. This article highlights key sections from EIS's new Utility Industry 1999 Environmental Research Report.© 1999 John Wiley & Sons, Inc. 相似文献
550.
Marsh surface sediment deposition and the role of tidal creeks: Implications for created and managed coastal marshes 总被引:3,自引:0,他引:3
Denise J. Reed Thomas Spencer Anne L. Murray Jonathan R. French Lynn Leonard 《Journal of Coastal Conservation》1999,5(1):81-90
The need to understand the processes contributing to marsh sedimentation has become more urgent with the recent recognition
of the role of tidal marshes as sea defences, as well as the many restoration efforts currently under way. This study was
designed to build upon previous sedimentation work at Scolt Head Island by Combining techniques for measuring short-term sedimentation,
with detailed assessment of hydroperiod, previously used only in comparison with longer-term accretion measurements or in
micro-tidal systems. Measurements of water level, sediment deposition (at various distances from the creek margin) and suspended
sediment concentration (SSC) (creek margin and an interior site) were made at Hut Marsh over three sequential over-marsh tides
during May 1994. Sediment trap data show a significant trend of declining sediment deposition away from the creek when data
from all three tides are combined. All tides show higher SSC on the flood tide than on the ebb tide at the creek margin location.
There is little difference in flood and ebb SSCs at the interior site. An order of magnitude decrease in sediment deposition
within 20 m on the creek shows the rapidity with which sediment is deposited on these marshes. Higher tides influence both
the magnitude and pattern of marsh surface sediment deposition. Increased creek velocities on higher tides provide more potential
for resuspension within the creek and increase the supply of sediment to the marsh surface. This study suggests that the design
of tidal creeks may be essential for the development of sustainable coastal marshes in restoration projects. 相似文献