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排序方式: 共有232条查询结果,搜索用时 15 毫秒
191.
DavidYoung RachelMonk 《世界环境》2002,(6):37-38
新西兰卫生部已宣布,从2001年12月7日起,将对所有转基因食品,即该食品最终成品中引入了新的DNA或异源蛋白,实行强制标签制度。任何进口和国产的食品只要含有转基因成分都将要求贴上标签。新西兰食品主管部门在2000年12月上旬根据食品标准法典18款修正案(转基因技术生产的食品法规)公布了以上决定。 相似文献
192.
Bridget Guerrero Rachel Owens Steve Amosson Kunlapath Sukcharoen John Richeson Lal Almas 《Journal of the American Water Resources Association》2019,55(3):670-679
The dairy industry in the Texas High Plains has experienced rapid expansion in the past two decades. This study assesses the impact of the increased presence of dairies on overall water use, crop composition, and the local economy. The increase in water use related to the dairy industry from 2000 to 2015 was primarily due to an increase in demand for drinking by the cows (direct water) as well as an increased demand for silage (indirect water). However, a comparative analysis (dairy presence vs. no dairy presence) from a single year indicates minimal impacts on total water use due to dairies. During the same time period, the number, size, and employment of related local business establishments have increased economic activity in rural areas. Editor's note : This paper is part of the featured series on Optimizing Ogallala Aquifer Water Use to Sustain Food Systems. See the February 2019 issue for the introduction and background to the series. 相似文献
193.
Bringing Out the Best in People: a Psychological Perspective 总被引:1,自引:0,他引:1
194.
Rachel T. Noble John H. Dorsey Molly Leecaster Victoria Orozco-Borbón Daniel Reid Kenneth Schiff Stephen B. Weisberg 《Environmental monitoring and assessment》2000,64(1):435-447
A regional survey of the microbiological water quality along the shoreline of the Southern California Bight (SCB), from Point Conception south to Ensenada, Mexico, was conducted during August, 1998, by 36 agencies under the coordination of the Southern California Coastal Water Research Project (SCCWRP). Microbiological water quality was assessed by calculating the percentage of shoreline-mile-days that exceeded bacterial indicator thresholds for total and fecal coliforms, total/fecal ratios, and enterococci. Sample sites were selected using a stratified random sampling approach, with the SCB recreational shoreline divided into six strata: high- and low-use sandy beaches, high- and low-use rocky shoreline, and perennial and ephemeral freshwater outlets. Samples were collected on a weekly basis at a total of 253 sites, beginning on August 2nd, 1998 and continuing for five weeks. Samples were analyzed by 22 participating labs using their normal methods (multiple tube fermentation, membrane filtration, Colilert® and/or Enterolert®). All labs met testing criteria established through intercalibration exercises and quality control check samples distributed during the sampling period. Nearly 95% of the shoreline-mile days did not exceed daily and monthly bacterial indicator thresholds, demonstrating good bacteriological water quality along the SCB shoreline. Freshwater outlets, comprised mainly of storm drains, had the poorest water quality with 60% and 40% of the shoreline-miles exceeding monthly and daily thresholds, respectively. Freshwater outlets were also more likely to demonstrate exceedances by multiple indicators at a single site, and repeat exceedances at sites over the five-week period. Compared with the southern California beaches, Mexican beaches had nearly 5 times the number of exceedances for total and fecal coliforms, and nearly 8 times the number of exceedances for total/fecal ratios. 相似文献
195.
Rachel Freeman Chris McMahon Patrick Godfrey 《International Journal of Sustainable Engineering》2017,10(4-5):260-271
AbstractRe-distributed manufacturing (RDM), broadly described as manufacturing done at a smaller-scale and locally, could be beneficial to business and urban society through creating jobs, reducing the environmental impacts of production, and improving resilience to future disturbances. Consideration of RDM within a city-region requires the consideration of a wide range of issues – societal, technical, economic and environmental. This paper presents the results of a study into the potential for RDM to contribute to a sustainable, resilient city in the face of a range of expected future disturbances on the city and on manufacturing sectors. The study took an integrated assessment approach which incorporated the development of a conceptual framework; a ‘strawman’ causal loop diagram which was reviewed by participants in a workshop; and a stock and flow system dynamics model that represents our understanding about the structure and behaviour of urban manufacturing. Several key themes emerged: similarities between RDM and traditional manufacturing, availability of physical space for RDM to be done, achieving urban resilience through RDM by enabling responsiveness to disturbances, changes in environmental impacts from production, additions or losses in jobs, the competitiveness of local manufacturing, and skills and innovation for RDM technologies. Further work is recommended. 相似文献
196.
Back-pedaling or continuing quietly? Assessing the impact of ICLEI membership termination on cities’ sustainability actions 总被引:1,自引:0,他引:1
Over the past decade, cities have emerged as leaders in sustainability and climate protection in the United States. ICLEI, a voluntary network of local governments, played an important role driving this trend. After years of steady growth, ICLEI became a target of political opposition and its membership dropped significantly from 2010 to 2012. This begs the question of whether cities’ termination of their ICLEI affiliation diminishes their implementation of sustainability actions. Two surveys administered in 2010 and 2014 provide data on cities’ implementation of an array of sustainability actions. Using a difference-in-differences (DiD) method, the impact of ICLEI termination on local governments’ administrative and policy commitments to sustainability is assessed. The results suggest that ending ICLEI membership does not significantly impact local sustainability actions, and also indicate that the durability of policy actions may be only loosely linked to the policies that justify them. 相似文献
197.
198.
Richard Schuster Rachel Buxton Jeffrey O. Hanson Allison D. Binley Jeremy Pittman Vivitskaia Tulloch Frank A. La Sorte Patrick R. Roehrdanz Peter H. Verburg Amanda D. Rodewald Scott Wilson Hugh P. Possingham Joseph R. Bennett 《Conservation biology》2023,37(3):e14048
Protected areas are a key instrument for conservation. Despite this, they are vulnerable to risks associated with weak governance, land-use intensification, and climate change. We used a novel hierarchical optimization approach to identify priority areas for expanding the global protected area system that explicitly accounted for such risks while maximizing protection of all known terrestrial vertebrate species. To incorporate risk categories, we built on the minimum set problem, where the objective is to reach species distribution protection targets while accounting for 1 constraint, such as land cost or area. We expanded this approach to include multiple objectives accounting for risk in the problem formulation by treating each risk layer as a separate objective in the problem formulation. Reducing exposure to these risks required expanding the area of the global protected area system by 1.6% while still meeting conservation targets. Incorporating risks from weak governance drove the greatest changes in spatial priorities for protection, and incorporating risks from climate change required the largest increase (2.52%) in global protected area. Conserving wide-ranging species required countries with relatively strong governance to protect more land when they bordered nations with comparatively weak governance. Our results underscore the need for cross-jurisdictional coordination and demonstrate how risk can be efficiently incorporated into conservation planning. Planeación de las áreas protegidas para conservar la biodiversidad en un futuro incierto 相似文献
199.
Restoration of foundation species promises to reverse environmental degradation and return lost ecosystem services, but a lack of standardized evaluation across projects limits understanding of recovery, especially in marine systems. Oyster reefs are restored to reverse massive global declines and reclaim valuable ecosystem services, but the success of these projects has not been systematically and comprehensively quantified. We synthesized data on ecosystem services associated with oyster restoration from 245 pairs of restored and degraded reefs and 136 pairs of restored and reference reefs across 3500 km of U.S. Gulf of Mexico and Atlantic coastlines. On average, restoration was associated with a 21-fold increase in oyster production (mean log response ratio = 3.08 [95% confidence interval: 2.58–3.58]), 34–97% enhancement of habitat provisioning (mean community abundance = 0.51 [0.41–0.61], mean richness = 0.29 [0.19–0.39], and mean biomass = 0.69 [0.39–0.99]), 54% more nitrogen removal (mean = 0.43 [0.13–0.73]), and 89–95% greater sediment nutrients (mean = 0.67 [0.27–1.07]) and organic matter (mean = 0.64 [0.44–0.84]) relative to degraded habitats. Moreover, restored reefs matched reference reefs for these ecosystem services. Our results support the continued and expanded use of oyster restoration to enhance ecosystem services of degraded coastal systems and match many functions provided by reference reefs. 相似文献
200.
The promising spread of sustainable agriculture in Asia 总被引:1,自引:0,他引:1
Despite great successes in increasing food production, Asia still faces enormous food security challenges. Most commentators agree that there will have to be increases in food production from existing agricultural land, but many are pessimistic about the future, judging likelihood of success on the basis of past performance of 'modern' agricultural development. Sustainable agriculture, though, offers entirely new opportunities, by emphasising the productive values of natural, social and human capital, all assets that Asian countries either have in abundance or that can be regenerated at relatively low financial cost.
This paper sets out an assets-based model of agricultural systems, together with a typology of eight approaches for sustainable agriculture improvements. In the 16 projects/initiatives spread across eight countries that are analysed, some 2.86 million households have substantially improved total food production on 4.93 million hectares, resulting in greatly improved household food security. Proportional yield increases are greatest in rainfed systems, but irrigated systems have seen small cereal yield increases combined with added production from additional productive system components (such as fish in rice, vegetables on dykes). The additional positive impacts on natural, social and human capital are also helping to build the assets base so as to sustain these improvements in the future.
This analysis indicates that sustainable agriculture can deliver large increases in food production in Asia. But spreading these to much larger numbers of farm households will not be easy. It will require fundamental policy reform. 相似文献
This paper sets out an assets-based model of agricultural systems, together with a typology of eight approaches for sustainable agriculture improvements. In the 16 projects/initiatives spread across eight countries that are analysed, some 2.86 million households have substantially improved total food production on 4.93 million hectares, resulting in greatly improved household food security. Proportional yield increases are greatest in rainfed systems, but irrigated systems have seen small cereal yield increases combined with added production from additional productive system components (such as fish in rice, vegetables on dykes). The additional positive impacts on natural, social and human capital are also helping to build the assets base so as to sustain these improvements in the future.
This analysis indicates that sustainable agriculture can deliver large increases in food production in Asia. But spreading these to much larger numbers of farm households will not be easy. It will require fundamental policy reform. 相似文献