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Jessica Spijkers Tiffany H Morrison Robert Blasiak Graeme S Cumming Matthew Osborne James Watson Henrik Österblom 《Fish and Fisheries》2018,19(5):798-806
Conflict over marine fishery resources is a growing security concern. Experts expect that global changes in our climate, food systems and oceans may spark or exacerbate resource conflicts. An initial scan of 803 relevant papers and subsequent intensive review of 31 fisheries conflict studies, focused on subnational and international conflicts, suggests that four substantial scientific gaps need addressing to improve our understanding of the nature and drivers of fisheries conflict. First, fisheries conflict and levels of conflict intensity are not precisely defined. Second, complex adaptive systems thinking is underutilized but has the potential to produce more realistic causal models of fishery conflict. Third, comparative large‐scale data and suitably integrative methodologies are lacking, underscoring the need for a standardized and comparable database of fisheries conflict cases to aid extrapolation beyond single case‐studies. Fourth, there is room for a more widespread application of higher order concepts and associated terminology. Importantly, the four gaps highlight the homogenized nature of current methodological and theoretical approaches to understanding fishery conflict, which potentially presents us with an oversimplified understanding of these conflicts. A more nuanced understanding of the complex and dynamic nature of fishery conflict and its causes is not only scientifically critical, but increasingly relevant for policymakers and practitioners in this turbulent world. 相似文献
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In vitro Utilization of Gold and Green Kiwifruit Oligosaccharides by Human Gut Microbial Populations
Parkar SG Rosendale D Paturi G Herath TD Stoklosinski H Phipps JE Hedderley D Ansell J 《Plant foods for human nutrition (Dordrecht, Netherlands)》2012,67(3):200-207
We examined the effects of whole kiwifruit on gut microbiota using an in vitro batch model of gastric-ileal digestion and colonic fermentation. Faecal fermentations of gold and green kiwifruit, inulin and water (control) digests were performed for up to 48?h. As compared to the control, gold and green kiwifruit increased Bifidobacterium spp. by 0.9 and 0.8 log(10) cfu/ml, respectively (P?0.001), and the Bacteroides-Prevotella-Porphyromonas group by 0.4 and 0.5 log(10) cfu/ml, respectively. Inulin only had a bifidogenic effect (+0.4 log(10) cfu/ml). This was accompanied with increases in microbial glycosidases, especially those with substrate specificities relating to the breakdown of kiwifruit oligosaccharides, and with increased generation of short chain fatty acids. The microbial metabolic activity was sustained for up to 48?h, which we attribute to the complexity of the carbohydrate substrate provided by whole kiwifruit. Kiwifruit fermenta supernatant was also separately shown to affect the in vitro proliferation of Bifidobacterium longum, and its adhesion to Caco-2 intestinal epithelial cells. Collectively, these data suggest that whole kiwifruit may modulate human gut microbial composition and metabolism to produce metabolites conducive to increased bifidobacteria-host association. 相似文献
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Phytophthora root rot on Abies fraseri trees was monitored from 2001 to 2007 within the disease front of a 12‐year‐old Virginia plantation where trees had been dying of the disease since 1994. After a slow increase in early foliage symptom development from July 2001 to September 2002, the frequency of A. fraseri trees with early symptoms accelerated for about 15 months. While the slow increase occurred during a 18.7% lower than normal rainfall period and the acceleration occurred during a 31.2% higher than normal rainfall period, the percentage of trees with early symptoms continued to increase during the mid‐winter months (December–February) when the estimated mean minimum daily soil temperature (25 cm depth) was unfavourable (<10°C) to Phytophthora cinnamomi pathogenic activity. The time required for trees to progress from early foliage symptoms to completely dead foliage, from November 2000 to October 2007, was highly variable, ranging from 4 to 35 months. Root recovery rates for P. cinnamomi, assayed on a selective medium, were 6.4 times greater for symptomatic foliage trees than for asymptomatic foliage trees in this deep, silt‐loam soil. Following an atypical cold period in February 2007, when the mean minimum daily soil temperature was 0.8°C, symptomatic roots yielded only a low level of germinable propagules of P. cinnamomi. Further, during an atypical midsummer in 2007 (June–August), when the soil water potential was at or below ?9 bars for 68 of 92 days, symptomatic roots yielded no germinable propagules of P. cinnamomi. Addition of thiophanate‐methyl to the selective medium aided P. cinnamomi isolation by inhibiting many undesired pythiaceous colonies growing from symptomatic roots. 相似文献
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