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T. Bruce Lauber Nancy A. Connelly Jeff Niederdeppe Barbara A. Knuth 《Human Dimensions of Wildlife》2014,19(5):458-468
We consider the implications of public trust administration principles for collaborative fish and wildlife management. Collaboration can increase the capacity of agencies to provide fish- and wildlife-related benefits but increases the ties of agencies to some stakeholders—potentially privileging those stakeholders’ needs. We conducted two case studies of collaborative management in which we identified ways that collaboration enhanced and detracted from agencies’ capacities. We found that collaboration led to benefits for agencies, but that agencies had to make tradeoffs in the goals and objectives they pursued. With regard to meeting public trust responsibilities, we hypothesized that: (a) agencies gain from collaboration when they do not have the capacity to provide a certain type of fish- or wildlife-related benefit on their own; but (b) it is more challenging for agencies to provide benefits through collaborative efforts when they work with organizations that have goals that differ considerably from their own. 相似文献
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Knuth DE 《Science (New York, N.Y.)》1976,194(4271):1235-1242
By presenting these examples, I have tried to illustrate four main points. 1) Finite numbers can be really enormous, and the known universe is very small. Therefore the distinction between finite and infinite is not as relevant as the distinction between realistic and unrealistic. 2) In many cases there are subtle ways to solve very large problems quickly, in spite of the fact that they appear at first to require examination of too many possibilities. 3) There are also cases where we can prove that a fairly natural problem is intrinsically hard, far beyond our conceivable capabilities. 4) It takes a good deal of skill to decide whether a given problem is in the easy or hard class; but even if a problem does turn out to be hard there are useful and interesting ways to change it into one that can be done satisfactorily. 相似文献
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Wolfgang Wilcke Sven Günter Fabian Alt Christiane Geißler Jens Boy Jana Knuth Yvonne Oelmann Michael Weber Carlos Valarezo Reinhard Mosandl 《Forest Ecology and Management》2009
Management of natural forests might be one option to reduce the high deforestation rate in Ecuador. We therefore evaluated the response of water and nutrient cycles in a natural tropical montane forest to improvement fellings with the aim of favoring economically valuable target trees which will later be harvested with additional ecosystem impacts not considered here. 相似文献
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Global assessment of organic contaminants in farmed salmon 总被引:1,自引:0,他引:1
Hites RA Foran JA Carpenter DO Hamilton MC Knuth BA Schwager SJ 《Science (New York, N.Y.)》2004,303(5655):226-229
The annual global production of farmed salmon has increased by a factor of 40 during the past two decades. Salmon from farms in northern Europe, North America, and Chile are now available widely year-round at relatively low prices. Salmon farms have been criticized for their ecological effects, but the potential human health risks of farmed salmon consumption have not been examined rigorously. Having analyzed over 2 metric tons of farmed and wild salmon from around the world for organochlorine contaminants, we show that concentrations of these contaminants are significantly higher in farmed salmon than in wild. European-raised salmon have significantly greater contaminant loads than those raised in North and South America, indicating the need for further investigation into the sources of contamination. Risk analysis indicates that consumption of farmed Atlantic salmon may pose health risks that detract from the beneficial effects of fish consumption. 相似文献
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Ryan M Knuth Whitney C Stewart Joshua B Taylor Bledar Bisha Carl J Yeoman Megan L Van Emon Thomas W Murphy 《Journal of animal science》2021,99(4)
Mastitis is an economically important disease and its subclinical state is difficult to diagnose, which makes mitigation more challenging. The objectives of this study were to screen clinically healthy ewes in order to 1) identify cultivable microbial species in milk, 2) evaluate somatic cell count (SCC) thresholds associated with intramammary infection, and 3) estimate relationships between udder and teat morphometric traits, SCC, and ewe productivity. Milk was collected from two flocks in early (<5 d) and peak (30 to 45 d) lactation to quantify SCC (n = 530) and numerate cultivable microbial species by culture-based isolation followed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS; n = 243) identification. Within flock and lactation stage, 11% to 74% (mean = 36%) of samples were culture positive. More than 50 unique identifications were classified by MALDI-TOF MS analysis, and Bacillus licheniformis (18% to 27%), Micrococcus flavus (25%), Bacillus amyloliquefaciens (7% to 18%), and Staphylococcus epidermidis (26%) were among the most common within flock and across lactation stage. Optimum SCC thresholds to identify culture-positive samples ranged from 175 × 103 to 1,675 × 103 cells/mL. Ewe productivity was assessed as total 120-d adjusted litter weight (LW120) and analyzed within flock with breed, parity, year, and the linear covariate of log10 SCC (LSCC) at early or peak lactation. Although dependent on lactation stage and year, each 1-unit increase in LSCC (e.g., an increase in SCC from 100 × 103 to 1,000 × 103 cells/mL) was predicted to decrease LW120 between 9.5 and 16.1 kg when significant. Udder and teat traits included udder circumference, teat length, teat placement, and degree of separation of the udder halves. Correlations between traits were generally low to moderate within and across lactation stage and most were not consistently predictive of ewe LSCC. Overall, the frequencies of bacteria-positive milk samples indicated that subclinical mastitis (SCM) is common in these flocks and can impact ewe productivity. Therefore, future research is warranted to investigate pathways and timing of microbial invasion, genomic regions associated with susceptibility, and husbandry to mitigate the impact of SCM in extensively managed ewes. 相似文献
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A general account is given in this paper of history, incidence, pathogen properties, morphogenesis, isolation, and culturing of Tahyna virus. Reference is also made to methods for detection, host spectrum, immunity, epizootiology, pathogenesis, and clinical symptoms in man and animals and also to aspects relating to pathological anatomy as well as to regular and differential diagnosis. 相似文献
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Simon Marcel Pierre Knuth Dennis Böhm Leonard Wiltschka Katrin Schatz Marlene Düring Rolf-Alexander 《Journal of Soils and Sediments》2022,22(2):496-508
Journal of Soils and Sediments - Organochlorine pesticides (OCPs) like lindane and DDT have been used extensively after World War II until the 1990s. Still, residues of these pesticides can be... 相似文献
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