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231.
Curtis M. Oldenburg Steven L. Bryant Jean-Philippe Nicot 《International Journal of Greenhouse Gas Control》2009,3(4):444-457
We have developed a certification framework (CF) for certifying the safety and effectiveness of geologic carbon sequestration (GCS) sites. Safety and effectiveness are achieved if CO2 and displaced brine have no significant impact on humans, other living things, resources, or the environment. In the CF, we relate effective trapping to CO2 leakage risk which takes into account both the impact and probability of leakage. We achieve simplicity in the CF by using (1) wells and faults as the potential leakage pathways, (2) compartments to represent environmental resources that may be impacted by leakage, (3) CO2 fluxes and concentrations in the compartments as proxies for impact to vulnerable entities, (4) broad ranges of storage formation properties to generate a catalog of simulated plume movements, and (5) probabilities of intersection of the CO2 plume with the conduits and compartments. We demonstrate the approach on a hypothetical GCS site in a Texas Gulf Coast saline formation. Through its generality and flexibility, the CF can contribute to the assessment of risk of CO2 and brine leakage as part of the certification process for licensing and permitting of GCS sites around the world regardless of the specific regulations in place in any given country. 相似文献
232.
Abstract: Models of what makes good koala habitat are a key to developing effective conservation policy and practices. Koala habitat models are based on (1) ecological studies of high-density koala populations in limited areas, (2) physiological studies of koala nutrition and characteristics of food plants, and (3) surveys of koala geographic distribution and biophysical features of forests and woodlands. The role of models in koala conservation varies because legislators, decisionmakers, land managers, and citizens have different expectations and uses for models. Although current habitat models address many of these needs, overall they lack sufficient certainty and authority to resolve disputes and develop policy. Unpublished and inadequately peer-reviewed data and models add to misinterpretation and argument. Improvements are needed in the decision-making process to increase the constructive involvement of all interest groups and to focus on the koala conservation problem, thereby reducing use of the popular media and courts of law to achieve objectives. 相似文献
233.
Extracting Humans from Nature 总被引:9,自引:0,他引:9
234.
Zhang Wei Price Steven J. Bonner Simon J. 《Environmental and Ecological Statistics》2021,28(2):405-422
Environmental and Ecological Statistics - Misidentification of animals is a common problem for many capture-recapture experiments. Considerably misleading inference may be obtained when traditional... 相似文献
235.
Daniel Ovando Jennifer E. Caselle Christopher Costello Olivier Deschenes Steven D. Gaines Ray Hilborn Owen Liu 《Conservation biology》2021,35(6):1861-1870
Marine protected areas (MPAs) cover 3–7% of the world's ocean, and international organizations call for 30% coverage by 2030. Although numerous studies show that MPAs produce conservation benefits inside their borders, many MPAs are also justified on the grounds that they confer conservation benefits to the connected populations that span beyond their borders. A network of MPAs covering roughly 20% of the Channel Islands National Marine Sanctuary was established in 2003, with a goal of providing regional conservation and fishery benefits. We used a spatially explicit bioeconomic simulation model and a Bayesian difference-in-difference regression to examine the conditions under which MPAs can provide population-level conservation benefits inside and outside their borders and to assess evidence of those benefits in the Channel Islands. As of 2017, we estimated that biomass densities of targeted fin-fish had a median value 81% higher (90% credible interval: 23–148) inside the Channel Island MPAs than outside. However, we found no clear effect of these MPAs on mean total biomass densities at the population level: estimated median effect was –7% (90% credible interval: –31 to 23) from 2015 to 2017. Our simulation model showed that effect sizes of MPAs of <30% were likely to be difficult to detect (even when they were present); smaller effect sizes (which are likely to be common) were even harder to detect. Clearly, communicating expectations and uncertainties around MPAs is critical to ensuring that MPAs are effective. We provide a novel assessment of the population-level effects of a large MPA network across many different species of targeted fin-fish, and our results offer guidance for communities charged with monitoring and adapting MPAs. 相似文献
236.
237.
Many recreational anglers practice catch-and-release angling, where fish are returned to the water with the presumption that
they will survive. However, not all fish survive, and those that do often experience sublethal consequences including injury
and stress. There is compelling scientific evidence that angler behavior and gear choice can affect the success of catch-and-release
as a management and conservation strategy. Because anglers often look to government natural resource agencies for guidance
on how to handle and release fish properly, there is a need to assess whether their outreach materials are readily accessible
and provide the necessary and correct information on the subject. Therefore, on-line catch-and-release guidelines developed
by state and provincial natural resource agencies across North America were evaluated to determine whether their guidelines
were consistent with the best available scientific information. This analysis revealed that there was immense variation in
the depth and breadth of coverage among jurisdictions. Agency guidelines contradicted one another in several areas including
air exposure, angling in deep water, venting trapped gases, and resuscitation. In many cases, the guidelines failed to provide
sufficient direction to actually be of use to anglers or provide direction consistent with contemporary scientific literature.
This analysis will assist with developing outreach materials that promote sustainable recreational fisheries and in maintaining
the welfare status of individual fish. 相似文献
238.
Yuichi Fukunishi Howard I. Browman Caroline M. F. Durif Reidun M. Bjelland Steven D. Shema David M. Fields Anne Berit Skiftesvik 《Marine Biology》2013,160(10):2591-2596
Levels of ultraviolet-B radiation (UV-B: 280–315 nm) reaching the earth’s surface have increased over the past few decades due to ozone depletion. It is well documented that exposure to UV-B radiation increases mortality in marine fish larvae. However, few studies have examined sub-lethal effects of UV-B radiation such as, for example, the possibility that it affects prey consumption by fish larvae. Atlantic cod larvae were exposed to a sub-lethal level of ultraviolet-B radiation (UV-B: 280–315 nm) for 15 h. After the exposure, rotifers (4/mL) were fed to cod larvae at three different post-exposure intervals (20 min, 3 and 6 h). Trials were replicated three times for each post-exposure interval. The number of rotifers in the gut and the percent of empty guts (number of fish with empty gut/number of fish examined × 100) were analyzed. Results were compared to those of unexposed fish (the control treatment). UV-B exposed cod larvae had consumed significantly fewer rotifers than control fish at all post-exposure intervals. There was no significant difference in the frequency of empty guts between fish in the UV-B treatment versus fish in the control treatment at any of the post-exposure time points (although the difference at 20 min post-exposure was borderline significant). These observations suggest that cod larvae exposed to sub-lethal levels of UV-B have lower net energy gain which may lead to reduced growth rate and possibly poorer survival. 相似文献
239.
Maricica Pacurari Diane Schwegler-Berry Sherri Friend Steven S. Leonard Robert R. Mercer Val Vallyathan 《毒物与环境化学》2013,95(5):1045-1072
Single-walled carbon nanotubes (SWCNT) are being developed to be used in many industrial and biomedical applications. However, SWCNT's durability and likely fibrous morphology have raised health concerns. The present investigations were focused on understanding the cellular and molecular mechanisms induced by raw SWCNT (SWCNT) in human bronchial-epithelial cells (BEAS-2B). Asbestos (crocidolite) was used as a positive control. Exposure of BEAS-2B cells to SWCNT induced apoptosis, DNA damage, and oxidative stress. The generation of hydroxyl radical (?OH) and increase of superoxide dismutase (SOD) activity were concentration-dependent. The increase in apoptosis was associated with activation of caspase-3, caspase-7, and poly (ADP-ribose) polymerase-1 (PARP-1). A short recovery period of 6?h of cells from SWCNT exposure resulted in reversal of caspase-3 and caspase-7, and a partial reversal of PARP-1 activation. The activation of PARP-1, caspase-3, and caspase-7 was only partially diminished after a recovery of 6?h from the exposure to crocidolite. Exposure of BEAS-2B cells to SWCNT resulted in the phosphorylation of protein p42/44 (p42/44) and protein p38 (p38). SWCNT did not induce protein serine-threonine kinase (AKT) phosphorylation. For all the above end points, crocidolite induced a greater response compared to SWCNT. SWCNT induced a significant activation of activator protein-1 (AP-1) and nuclear factor kappa B (NF-κB), and the effect was inhibited by mitogen-activated protein kinase (MAPK) inhibitors. SWCNT also induced significant increase in the expression levels of c-Jun, βIGH3, and CD44 genes. The results of this study show that the molecular mechanism for raw SWCNT-mediated toxicity in BEAS-2B cells is through the activation of caspase-3, caspase-7, and PARP-1. Furthermore, the mechanism of AP-1 and NF-κB activation is through MAPK. This bioactivity of raw SWCNT is associated with the generation of oxidative stress and DNA damage. Considering the role of airway epithelium as a critical barrier for normal pulmonary function and focal point for tumor development, this study demonstrates that raw SWCNT activate molecular events which may be linked to adverse biological responses implicated in pulmonary diseases. 相似文献
240.
Steven A Cobb 《Journal of Environmental Economics and Management》1977,4(3):214-218
There has been considerable debate as to the information contained in the coefficients of a cross-sectional regression of site rent on air quality. Much of the confusion surrounding the analysis of the relationships (a) between air quality changes and property value changes, (b) between property value changes and benefits derived from quality changes, and (c) between the estimated cross-sectional coefficients and all of the above, can be cleared up by a discussion of the meaning of the hedonic equation. In that context, the implications for demand analysis are clarified. 相似文献