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531.
Hummel Michelle A. Wood Nathan J. Schweikert Amy Stacey Mark T. Jones Jeanne Barnard Patrick L. Erikson Li 《Regional Environmental Change》2018,18(5):1343-1355
Regional Environmental Change - Sea level is projected to rise over the coming decades, further increasing the extent of flooding hazards in coastal communities. Efforts to address potential... 相似文献
532.
Sorrel Jones Aidan Keane Freya St John Juliet Vickery Sarah Papworth 《Conservation biology》2019,33(4):895-905
Audience segmentation could help improve the effectiveness of conservation interventions. Marketers use audience segmentation to define the target audience of a campaign. The technique involves subdividing a general population into groups that share similar profiles, such as sociodemographic or behavioral characteristics. Interventions are then designed to target the group or groups of interest. We explored the potential of audience segmentation for use in defining conservation target groups with a case study of hunters in Liberia. Using 2 data sets describing households (n = 476) and hunters (n = 205), we applied a clustering method in which infinite binomial mixture models group hunters and households according to livelihood and behavior variables and a simple method to define target groups based on hunting impact (hunting households and high-impact hunters). Clusters of hunters and households differed in their experiences with confiscation of catch at roadblocks and participation in livelihood-support programs, indicating that these interventions operate unevenly across subsets of the population. By contrast, the simple method masked these insights because profiles of hunting households and high-impact hunters were similar to those of the general population. Clustering results could be used to guide the development of livelihood and regulatory interventions. For example, a commonly promoted agricultural activity, cocoa farming, was practiced by only 2% (out of 87) of the largest hunter cluster of nonlocal gun hunters but was prevalent among local trappers, suggesting that assistance aimed at cocoa farmers is less appropriate for the former group. Our results support the use of audience segmentation across multiple variables to improve targeted intervention designs in conservation. 相似文献
533.
534.
The use of proteins in blending with traditional polymers in the formation of thermoplastics can produce plastics with properties that are superior to traditional petroleum-based plastics. We investigated the physical and thermal properties of albumin and zein thermoplastic blends plasticized with glycerol and mixed with varying amounts of low-density polyethylene (LDPE). Several mechanical models were utilized to determine how tensile properties will be altered when varying amounts of protein/LDPE were added into the thermoplastic blend. When analyzed for thermal properties, we found that as the amount of LDPE in the thermoplastic blend increased, the resulting plastic possessed thermal properties that were more similar to pure LDPE plastics. In terms of mechanical properties, comparison between the experimental data and model predictions points to a synergistic effect between albumin and LDPE that leads to higher modulus, while a potential lack of compatibility between zein and LDPE leads to a plastic with lower modulus. Based on our results, the use of albumin and zein proteins when blended with LDPE in the production of thermoplastics has potential use in the areas of medical and food packaging applications. 相似文献
535.
Parvulastra exigua, a species that lacks a dispersive larva, is paradoxically one of the most widely distributed and abundant sea stars in Australia.
The potential that self-fertilization and successful development of self-generated progeny might contribute to population
maintenance in this species was investigated through induction of spawning in isolated individuals collected from five populations
near Sydney, New South Wales (34°S, 151°E), during the spawning period (August–October 2010, 2011). Evidence of selfing differed
significantly among the five populations but the level of selfing within individual egg masses did not. Overall, there was
a mean of 8.9% fertilization in egg masses with embryos. Some clutches developed to the juvenile stage while others arrested
development before hatching. The presence of miniscule testis tissue in gonads that appeared to be ovaries indicated that
hermaphroditism may be more common in some populations than indicated by anatomy. Mixed mating (selfing + outcrossing), pseudocopulation
during egg laying and developmental success of self-fertilized embryos may contribute to the ecological success of P. exigua. These might influence population genetic structure and would facilitate establishment of founder populations by a small
number of migrants. 相似文献
536.
Jess Jones Steven Ahlstedt Brett Ostby Braven Beaty Michael Pinder Nathan Eckert Robert Butler Don Hubbs Craig Walker Shane Hanlon John Schmerfeld Richard Neves 《Journal of the American Water Resources Association》2014,50(4):820-836
The Clinch River is located in northeastern Tennessee (TN) and southwestern Virginia (VA) of the United States, and contains a diverse mussel assemblage of 46 extant species, including 20 species listed as federally endangered. To facilitate quantitative monitoring of the fauna, quadrat data were collected from 2004 to 2009 at 18 sites in the river, including 12 sites in TN and 6 sites in VA. Thirty‐eight mussel species were collected alive in total from quadrat samples taken annually at sites in the TN section of the river. Over the five‐year study period, mussel density averaged 25.5 m?2 at all sites sampled in TN. In contrast, mussel density averaged only 3.1 m?2 at sites sampled in VA. The best historical site in VA was Pendleton Island in Scott County, where mussel density was estimated as high as 25 m?2 in 1979, comparable to current densities recorded in TN. Mussel densities are now <1 m?2, indicating a collapse of the fauna. A severe reduction in mussel abundance has occurred in a 68‐km section of the river from St. Paul, VA, downstream to approximately Clinchport, VA (river kilometers 411.5‐343.3). While the environmental factors responsible for the faunal decline are largely unknown, they must have been severe and sustained to reduce such large populations to their current low levels. Long‐term water and habitat quality monitoring is needed to determine whether environmental degradation is still occurring in the river. 相似文献
537.
Jennifer E. Price Carl E. Zipper Jess W. Jones Christopher T. Franck 《Journal of the American Water Resources Association》2014,50(4):837-858
The Clinch River, in eastern United States, supports a diverse freshwater fauna including endangered mussels. Although mussel populations are stable in the Clinch's northeastern Tennessee segment, long‐term declines have been documented upstream in Virginia. We analyzed water and sediment quality data collected by government agencies from the 1960s through 2013 in an effort to inform current management. The river was divided into sections considering data availability and major tributaries. We tested for spatial differences among river sections and for temporal trends, and compared measured values to potentially protective levels if available. Ammonia concentrations approaching and exceeding protective levels were recorded, most often during the 1970s and 1980s in upstream sections. Sediment metals occurred at levels potentially causing biological effects, mainly during the 1980s and 1990s. In the 2000s, water‐column metals have been well below protective levels for general aquatic life. Dissolved solids (DS) increased in most river sections over the study period but mussel‐specific protective levels are not known. Analysis of water pH, total N, and total P did not generate conservation concern. Enhanced monitoring for sediment metals, water‐column metals, and ionic composition of DS; closer alignment of agency water monitoring practices in the two states; and research to determine biological effects of DS at current and anticipated levels can aid future conservation management. 相似文献
538.
Nadine Mellor Colin Mackay Claire Packham Rhiannon Jones David Palferman Simon Webster Peter Kelly 《Safety Science》2011,49(7):1040-1046
The aim of this paper is to identify what constituted barriers to progress in the implementation of the Management Standards for preventing and reducing work-related stress nationally, an approach advocated by the Health and Safety Executive in Great Britain. Data were collected from more than 100 public sector organisations through inspector visits and research interviews. Findings show that under supportive contexts, organisations were able to follow the process of a stepwise method for assessing psychosocial risks and implementing interventions using HSE assessment tools and guidance. Main enabling factors included the active and visible support from senior management, human resource departments, and line managers; regular communications on progress, sufficient organisational capability in terms of resources and expertise; departmental/team level assessment as opposed to an overall corporate wide assessment, and involvement of key stakeholders (e.g. Trade Union, employees). Some of the critical barriers across many public sector organisations included in this study were: major or on-going organisational changes; lack of organisational capability; and the resource intensive aspect of the method requiring focus groups in addition to stress survey data. Implications of the findings for policy development are discussed. 相似文献
539.
Bigliardi Ana Paula dos Santos Marina Fernandes Caroline Lopes Feijo Garcia Edariane Menestrino dos Santos Marcelli Evans Telles Jones Marcus Herbert Soares Maria Cristina Flores Baisch Ana Luíza Muccillo da Silva Júnior Flavio Manoel Rodrigues 《Environmental science and pollution research international》2022,29(31):46803-46812
Environmental Science and Pollution Research - Coal mining and burning activities in coal-fired power plants are among the most polluting activities in developing countries. In Brazil, the Candiota... 相似文献
540.