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S. T. Garnett S. H. M. Butchart G. B. Baker E. Bayraktarov K. L. Buchanan A. A. Burbidge A. L. M. Chauvenet L. Christidis G. Ehmke M. Grace D. G. Hoccom S. M. Legge I. Leiper D. B. Lindenmayer R. H. Loyn M. Maron P. McDonald P. Menkhorst H. P. Possingham J. Radford A. E. Reside D. M. Watson J. E. M. Watson B. Wintle J. C. Z. Woinarski H. M. Geyle 《Conservation biology》2019,33(2):456-468
Although evidence-based approaches have become commonplace for determining the success of conservation measures for the management of threatened taxa, there are no standard metrics for assessing progress in research or management. We developed 5 metrics to meet this need for threatened taxa and to quantify the need for further action and effective alleviation of threats. These metrics (research need, research achievement, management need, management achievement, and percent threat reduction) can be aggregated to examine trends for an individual taxon or for threats across multiple taxa. We tested the utility of these metrics by applying them to Australian threatened birds, which appears to be the first time that progress in research and management of threats has been assessed for all threatened taxa in a faunal group at a continental scale. Some research has been conducted on nearly three-quarters of known threats to taxa, and there is a clear understanding of how to alleviate nearly half of the threats with the highest impact. Some management has been attempted on nearly half the threats. Management outcomes ranged from successful trials to complete mitigation of the threat, including for one-third of high-impact threats. Progress in both research and management tended to be greater for taxa that were monitored or occurred on oceanic islands. Predation by cats had the highest potential threat score. However, there has been some success reducing the impact of cat predation, so climate change (particularly drought), now poses the greatest threat to Australian threatened birds. Our results demonstrate the potential for the proposed metrics to encapsulate the major trends in research and management of both threats and threatened taxa and provide a basis for international comparisons of evidence-based conservation science. 相似文献
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Environmental and Ecological Statistics - Species distribution modelling (SDM) is a family of statistical methods where species occurrence/density/richness are combined with environmental... 相似文献
396.
G. Yuan D. Chen L. Yin Z. Wang L. Zhao J.Y. Wang 《Waste management (New York, N.Y.)》2014,34(6):1045-1050
In this research a gas–liquid fluidized bed reactor was developed for removing chlorine (Cl) from polyvinyl chloride (PVC) to favor its pyrolysis treatment. In order to efficiently remove Cl within a limited time before extensive generation of hydrocarbon products, the gas–liquid fluidized bed reactor was running at 280–320 °C, where hot N2 was used as fluidizing gas to fluidize the molten polymer, letting the molten polymer contact well with N2 to release Cl in form of HCl. Experimental results showed that dechlorination efficiency is mainly temperature dependent and 300 °C is a proper reaction temperature for efficient dechlorination within a limited time duration and for prevention of extensive pyrolysis; under this temperature 99.5% of Cl removal efficiency can be obtained within reaction time around 1 min after melting is completed as the flow rate of N2 gas was set around 0.47–0.85 Nm3 kg?1 for the molten PVC. Larger N2 flow rate and additives in PVC would enhance HCl release but did not change the final dechlorination efficiency; and excessive N2 flow rate should be avoided for prevention of polymer entrainment. HCl is emitted from PVC granules or scraps at the mean time they started to melt and the melting stage should be taken into consideration when design the gas–liquid fluidized bed reactor for dechlorination. 相似文献
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Pesticide leaching models are being used to assist in the regulation and management of pesticides by indicating their potential for leaching to groundwater. Uncertainty in model input data is not, regrettably, included in most pesticide leaching assessments. In the work described here, we use logarithmic transformations of the attenuation factor (AF), a simple process-based index model, to represent uncertainty in a pesticide leaching assessment. Characterization of a wide range of pesticides as `leachers' or `non-leachers' for a specific Hawaii hydrogeological setting is facilitated by comparing the log-transformed AF, designated AFR, for each chemical with two reference chemicals for which leaching behavior in Hawaii is known. Defining a mean and uncertainty interval for the AFR index of each chemical being ranked provides a practical method of incorporating data uncertainty into a regulatory protocol. 相似文献
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Z. M. Grahovac S. S. Mitić E. T. Pecev A. N. Pavlović 《Journal of environmental science and health. Part. B》2013,48(8):783-789
In the present study, a new sensitive and simple kinetic-spectrophotometric method for the determination of the insecticide diflubenzuron [1-(4-chlorophenyl)-3-(2,6-diflubenzoil)urea] is proposed. The method is based on the inhibited effect of diflubenzuron on the oxidation of sulphanilic acid (SA) by hydrogen peroxide in phosphate buffer in presence Cu(II) ion. Diflubenzuron was determined with linear calibration graph in the interval from 0.31 to 3.1 μg mL?1 and from 3.1 to 31.0 μg mL?1. The optimized conditions yielded a theoretical detection limit of 0.18 μg mL?1corresponding to 0.036 mg Kg?1mushroom sample based on the 3Sb criterion. The RSD is 5.03–1.83 % and 2.81–0.71 % for the concentration interval of diflubenzuron 0.31–3.1 μg mL?1and 3.1–31.0 μg mL?1, respectively. The reaction was followed spectrophotometrically at 370 nm. The kinetic parameters of the reaction are reported, and the rate equations are suggested. The developed procedure was successfully applied to the rapid determination of diflubenzuron in spiked mushroom samples of different mushroom species. The HPLC method was used like a comparative method to verify results. 相似文献
400.
The cationic polymerization of soybean oils was initiated by boron trifluoride diethyl etherate in supercritical carbon dioxide
medium. The resulting polymers had molecular weight ranging from 21,842 to 118,300 g/mol. Nuclear magnetic resonance spectroscopy
and gel permeation chromatography analysis confirmed the polymerization had occurred. Parameters affecting the polymerization
were studied, which included initiator amount and reaction time. Results show that the longer reaction time, up to 3 h, favored
the higher molecular weight of polymers at conditions of 140 °C and initiator BF3·OEt2 (2.5 g, 0.018 mol). When reaction time was increased further, the molecular weight of polymers stayed the same or slightly
decreased. Increased concentration of initiator gave the higher molecular weight of polymers. The high molecular weight polymers
were possibly formed through two path ways: polymerization and intermolecular Diels-Alder reaction. 相似文献