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排序方式: 共有247条查询结果,搜索用时 15 毫秒
81.
Sustainable seafood initiatives began with efforts to promote and certify seafood sourced from well‐managed stocks caught with a reduced impact on the marine environment. More recently, social equity in fisheries has been the subject of increased concern with suggestions that seafood cannot be certified as sustainable if its production results in social harm, such as unfair wages or the use of forced or child labour. Together with local seafood, which has been promoted as an eco‐friendly and socially conscious alternative to globally sourced seafood, these initiatives signal a growing interest in fisheries as a social–ecological system. However, this increasingly complex landscape of environmental sustainability and social justice may be difficult for the public and seafood consumers to navigate. Here, we investigate consumer understanding of and responsiveness to a range of seafood sustainability initiatives by testing preferences and willingness to pay (WTP) for seafood across the three types of sustainability: ecological sustainability, local origin and social sustainability. More than half of respondents demonstrated good understandings of both ecological sustainability and social sustainability with respect to seafood, and respondents were willing to pay more for all three types of sustainability. However, WTP for social sustainability benefits was the lowest, and consumers perceived a high degree of overlap of these benefits with those from locally sourced seafood. These results indicate that seafood certification taking a system‐wide approach has potential to succeed, but that it will need to emerge in concert with the increased public education about social problems associated with globalized fisheries. 相似文献
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83.
Journal of Soils and Sediments - 相似文献
84.
Zhang Di Ding Aifang Li Ting Wu Xiaoxia Liu Yanju Naidu Ravi 《Journal of Soils and Sediments》2021,21(6):2262-2272
Journal of Soils and Sediments - This study aims to investigate the dynamic changes over time in the immobilization efficiency of hydroxyapatite, bentonite, and biochar for Cd and Pb... 相似文献
85.
TONG De-wen WANG Jin-yi Brain Patchett Ravi Gooneratne 《中国农业科学(英文版)》2006,5(10):793-797
Lolines are a group of saturated pyrrolizidine alkaloids that possess broad bioactivity against a wide array of herbivorous insects. However, they do not exhibit toxicity to ruminants such as cattle and sheep. In order to study the direct and potential physiological effects on ruminants and the mechanism of insecticide/insectifuge, the distribution of loline alkaloids in endophyte-infected meadow fescue and the seasonal change of the distribution were analyzed. The crowns, roots and leaves of endophyte-infected meadow fescue at its four different growth periods, i.e., spring, summer, early autumn and late autumn, in New Zealand were colleted. After powdering, organic solvent extraction and purification by column chromatography, all loline alkaloid samples were analyzed by capillary gas chromatography with 4-phenylmorpholine (PM) as an internal standard. The analytic results showed that the loline contents in the roots, crowns and leaves of endophyte-infected meadow fescue vary with seasons. Even within the same season, the distribution of lolines in endophyte-infected meadow fescue varies. During summer, lolines mainly existed in the leaves and roots, but in early autumn, they are produced in the crowns. It was concluded that, lolines were mainly produced in the leaves and roots of endophyte-infected meadow fescue. In gas chromatographic analysis, N-formylloline, the major component of loline alkaloid in the plant, was employed to assay the alkaloids. 相似文献
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87.
Jin Hee Park Nanthi Bolan Mallavarapu Megharaj Ravi Naidu 《Water, air, and soil pollution》2012,223(2):599-608
Lead forms stable compounds with phosphate and the immobilized Pb becomes less available to soil biota. In this study, we
tested the bioavailabilty of Pb using earthworms (Eisenia fetida) and plants after immobilization of Pb by a soluble P compound and an insoluble rock phosphate compound in the presence of
phosphate-solubilizing bacteria (Enterobacter sp.). Rock phosphate in the presence of phosphate-solubilizing bacteria and a soluble P compound enhanced Pb immobilization
as measured by NH4NO3-extractable Pb concentration, thereby reduced its bioavailability as evaluated by earthworm Pb loading and sunflower (Helianthus annuus) Pb uptake under greenhouse conditions. However, soluble P treatment increased the concentration of Pb in soil solution thereby
inhibited the root elongation of mustard (Brassica hirta) seedlings. Sunflower plants in the Pb-spiked soil without P amendments showed symptoms of necrosis and stunting because
of Pb toxicity. Both soluble and insoluble P treatments significantly increased shoot and root weight and decreased Pb concentration
in shoot by more than 50% compared to the control. However, high Pb concentration in soil solution was found in soluble P
treatment, which can be attributed to dissolved organic carbon–Pb complex formation, thereby increasing Pb mobility. The inoculation
of phosphate-solubilizing bacteria can facilitate phytostabilization of Pb-contaminated site. 相似文献
88.
The effect of different nutrient media on growth, physicochemical, and agar properties of the marine algae Gracilaria cliftonii was investigated in ocean water (OW) and inland saline water (ISW). G. cliftonii fronds were cultured in 500-mL and 25-L containers with different nutrient media: Aquasol, Total, Guillard f2, Walnes, and Modified-Provasoli's Enriched Seawater in OW and ISW at 35 ppt. Specific growth rate (SGR) was higher in OW than ISW irrespective of nutrient media in both volumes. Growth of G. cliftonii in Guillard f2-supplemented OW was significantly higher than other nutrient media in both water types. Nutrient media had no influence on growth and agar properties. However, f2?supplemented OW resulted in significantly higher agar yield (58.3% db) as compared to other media. Either f2 or Walnes media are preferred nutrient sources for culturing G. cliftonii in ocean and inland saline water. 相似文献
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90.
The International Maize and Wheat Improvement Center (CIMMYT) is the global leader in publicly-funded maize and wheat research and in farming systems based on these crops. CIMMYT leads the Global Wheat Program (GWP), which includes some of the largest wheat breeding programs in the world. The GWP has been successful in developing wheat germplasm that is used extensively worldwide. Wheat quality improvement is a central component of all the breeding efforts at CIMMYT and the Wheat Chemistry and Quality Laboratory represents an integral part of the breeding programs. Wheat quality is addressed at CIMMYT over the full range of this very wide and variable concept with milling, processing, end-use and nutritional quality targeted. Wheat progenitors and advanced lines developed by the breeders are assessed for diverse quality attributes, with the aim of identifying those that fulfill the requirements in terms of milling, processing, end-use and nutritional quality in different target regions. Significant research is conducted to make more efficient the integration of wheat quality traits in the breeding programs. The main topics being addressed are (1) methodologies to analyze grain quality traits, (2) genetic control and environmental effects on quality traits, (3) characterization of genetic resources for quality improvement, and (4) diversifying grain properties for novel uses. 相似文献