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771.
Chung‐Min Liao Huang‐Min Liang 《Journal of environmental science and health. Part. B》2013,48(3):357-378
Abstract Two models for evaluating the contents and advection of manure moisture on odor causing volatile organic compounds (VOC‐odor) volatilization from stored swine manure were studied for their ability to predict the volatilization rate (indoor air concentration) and cumulative exposure dose: a MJ‐I model and a MJ‐II model. Both models simulating depletion of source contaminant via volatilization and degradation based on an analytical model adapted from the behavior assessment model of Jury et al. In the MJ‐I model, manure moisture movement was negligible, whereas in the MJ‐II model, time‐dependent indoor air concentrations was a function of constant manure moisture contents and steady‐state moisture advection. Predicted indoor air concentrations and inhaled doses for the study VOC‐odors of p‐cresol, toluene, and p‐xylene varied by up to two to three orders of magnitude depending on the manure moisture conditions. The sensitivity analysis of both models suggests that when manure moisture movement exists, simply MJ‐I model is inherently not sufficient to represent a more generally volatilization process, which can even become stringent as moisture content increases. The conclusion illustrates how one needs to include a wide variety of manure moisture values in order to fully assess the complex volatilization mechanisms that are present in a real situation. 相似文献
772.
Pseudomonas sp. (Strain 10–1B): A potential inoculum candidate for green and sustainable remediation 下载免费PDF全文
Maryam Bello‐Akinosho Rasheed Adeleke Mapitsi S. Thantsha Mphekgo Maila 《补救:环境净化治理成本、技术与工艺杂志》2017,27(3):75-79
Soil pollution caused by polycyclic aromatic hydrocarbons (PAHs) is a consequence of various industrial processes which destabilizes the ecosystem. Bioremediation by bacteria is a cost‐effective and environmentally safe solution for reducing or eliminating pollutants in soils. In the present study, we artificially polluted agricultural soil with used automobile engine oil with a high PAH content and then isolated bacteria from the soil after 10 weeks. Pseudomonas sp. strain 10–1B was isolated from the bacterial community that endured this artificial pollution. We sequenced its genomic DNA on Illumina MiSeq sequencer and evaluated its ability to solubilize phosphate, fix atmospheric nitrogen, and produce indoleacetic acid, in vitro, to ascertain its potential for contribution to soil fertility. Its genome annotation predicted several dioxygenases, reductases, ferredoxin, and Rieske proteins important in the ring hydroxylation initiating PAH degradation. The strain was positive for the soil fertility attributes evaluated. Such combination of attributes is important for any potential bacterium partaking in sustainable bioremediation of PAH‐polluted soil. 相似文献
773.
Sam Lapp Tianhao Wu Corinne Richards-Zawacki Jamie Voyles Keely Michelle Rodriguez Hila Shamon Justin Kitzes 《Conservation biology》2021,35(5):1659-1668
Anurans (frogs and toads) are among the most globally threatened taxonomic groups. Successful conservation of anurans will rely on improved data on the status and changes in local populations, particularly for rare and threatened species. Automated sensors, such as acoustic recorders, have the potential to provide such data by massively increasing the spatial and temporal scale of population sampling efforts. Analyzing such data sets will require robust and efficient tools that can automatically identify the presence of a species in audio recordings. Like bats and birds, many anuran species produce distinct vocalizations that can be captured by autonomous acoustic recorders and represent excellent candidates for automated recognition. However, in contrast to birds and bats, effective automated acoustic recognition tools for anurans are not yet widely available. An effective automated call-recognition method for anurans must be robust to the challenges of real-world field data and should not require extensive labeled data sets. We devised a vocalization identification tool that classifies anuran vocalizations in audio recordings based on their periodic structure: the repeat interval-based bioacoustic identification tool (RIBBIT). We applied RIBBIT to field recordings to study the boreal chorus frog (Pseudacris maculata) of temperate North American grasslands and the critically endangered variable harlequin frog (Atelopus varius) of tropical Central American rainforests. The tool accurately identified boreal chorus frogs, even when they vocalized in heavily overlapping choruses and identified variable harlequin frog vocalizations at a field site where it had been very rarely encountered in visual surveys. Using a few simple parameters, RIBBIT can detect any vocalization with a periodic structure, including those of many anurans, insects, birds, and mammals. We provide open-source implementations of RIBBIT in Python and R to support its use for other taxa and communities. 相似文献
774.
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
775.
Irasema Alcntara‐Ayala 《Disasters》2019,43(Z1):S18-S27
LA RED (Network of Social Studies on the Prevention of Disasters in Latin America) has become the most influential group analysing disasters in Latin America and the Caribbean. Its contributions have paved the way for a new way of understanding disasters, disaster risk, and their management, concerning: (i) that disasters are not natural, but socially constructed; (ii) the inherent nexus between disaster risk, development, and the environment; (iii) the significance of small‐ and medium‐sized disasters and extensive and intensive risks; (iv) disaster risk management at the local level; and (v) integrated disaster risk research and the need for forensic investigations of disasters. As a result of this unification of challenges, intellectual communities of connected individuals were formed. Nonetheless, a focus on territorial management, exposure, and vulnerability remains a challenge for academia. In addition, the labyrinths of disaster risk governance must be disentangled by other stakeholders, such as national authorities, policymakers, and practitioners. 相似文献
776.
Understanding the circumstances and conditions surrounding disaster‐attributed deaths may contribute to designing and implementing emergency preparedness and response programmes. This paper introduces a three‐step cluster analysis of multiple binary variables to investigate mortality patterns related to tropical cyclones. It is designed to overcome the difficulties of performing cluster analysis in a disaster database that is composed in part of nominal variables and is unavoidably incomplete owing to missing information. The first step in the process codes all variables as binary data in order to accommodate the nominal variables. The second step calculates Spearman's rank correlation coefficients for pairs of variables. And the third step subjects the correlation coefficients to cluster analysis. Data related to 1,575 deaths attributed to tropical cyclones (also known as typhoons) that struck Taiwan between 2000 and 2015 are used to illustrate the method. The results yield two distinct groups of variables that are worthy of further exploration. 相似文献
777.
Associations of Forest Cover,Fragment Area,and Connectivity with Neotropical Understory Bird Species Richness and Abundance 总被引:1,自引:0,他引:1
Alexandre Camargo Martensen Milton Cezar Ribeiro Cristina Banks‐Leite Paulo Inácio Prado Jean Paul Metzger 《Conservation biology》2012,26(6):1100-1111
Theoretical and empirical studies demonstrate that the total amount of forest and the size and connectivity of fragments have nonlinear effects on species survival. We tested how habitat amount and configuration affect understory bird species richness and abundance. We used mist nets (almost 34,000 net hours) to sample birds in 53 Atlantic Forest fragments in southeastern Brazil. Fragments were distributed among 3 10,800‐ha landscapes. The remaining forest in these landscapes was below (10% forest cover), similar to (30%), and above (50%) the theoretical fragmentation threshold (approximately 30%) below which the effects of fragmentation should be intensified. Species‐richness estimates were significantly higher (F= 3715, p = 0.00) where 50% of the forest remained, which suggests a species occurrence threshold of 30–50% forest, which is higher than usually occurs (<30%). Relations between forest cover and species richness differed depending on species sensitivity to forest conversion and fragmentation. For less sensitive species, species richness decreased as forest cover increased, whereas for highly sensitive species the opposite occurred. For sensitive species, species richness and the amount of forest cover were positively related, particularly when forest cover was 30–50%. Fragment size and connectivity were related to species richness and abundance in all landscapes, not just below the 30% threshold. Where 10% of the forest remained, fragment size was more related to species richness and abundance than connectivity. However, the relation between connectivity and species richness and abundance was stronger where 30% of the landscape was forested. Where 50% of the landscape was forested, fragment size and connectivity were both related to species richness and abundance. Our results demonstrated a rapid loss of species at relatively high levels of forest cover (30–50%). Highly sensitive species were 3‐4 times more common above the 30–50% threshold than below it; however, our results do not support a unique fragmentation threshold. Asociaciones de la Cobertura Forestal, Superficie del Fragmento y Conectividad con la Riqueza y Abundancia de Aves Neotropicales de Sotobosque 相似文献
778.
ABSTRACT: The purpose of this paper is to investigate the sensitivity of a hydrologic models to the type of DEM used. This was done while modeling basin water quality with 1:24,000 and 1:250,000 U.S. Geological Survey DEMs as input to model hydro‐logical processes. The manner in which the model results were sensitive to the choice of raster cell size (scale) is investigated in this study. The Broadhead watershed, located in New Jersey, USA, was chosen as a study area. Curve numbers were estimated by a trial and error to match simulated and observed total discharge. Monthly runoff for the watershed was used in the calibration process. Higher runoff volumes were simulated by the model when the 1:24,000 DEM were used as input data, probably due to the finer resolution which simulated increased average slope and hence higher estimated runoff from the watershed. As the simulated slope of the watershed is flatten with the 1:250,000 DEM, the response of stream flow was delayed and simulated less runoff volume. 相似文献
779.
Soon Thiam Khu Shie‐Yui Liong Vladan Babovic Henrik Madsen Nitin Muttil 《Journal of the American Water Resources Association》2001,37(2):439-451
ABSTRACT: Genetic programming (GP), a relatively new evolutionary technique, is demonstrated in this study to evolve codes for the solution of problems. First, a simple example in the area of symbolic regression is considered. GP is then applied to real‐time runoff forecasting for the Orgeval catchment in France. In this study, GP functions as an error updating scheme to complement a rainfall‐runoff model, MIKE11/NAM. Hourly runoff forecasts of different updating intervals are performed for forecast horizons of up to nine hours. The results show that the proposed updating scheme is able to predict the runoff quite accurately for all updating intervals considered and particularly for updating intervals not exceeding the time of concentration of the catchment. The results are also compared with those of an earlier study, by the World Meteorological Organization, in which autoregression and Kalman filter were used as the updating methods. Comparisons show that GP is a better updating tool for real‐time flow forecasting. Another important finding from this study is that nondimensionalizing the variables enhances the symbolic regression process significantly. 相似文献
780.
Two studies were used to examine the moderating effect of gender on the justice–outcome relationships. Contrary to hypothesis, gender moderates the relationship between distributive justice and trust in supervisor in sample 1. It is possible that women are concentrating more on distributive issues rather than procedural justice issues in order to address past pay discrepancies. Further, gender did not moderate any other justice–outcome relationships. These results may indicate a recent trend toward work value similarity and narrowing of gender differences. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献