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61.
Cooperatives are increasingly advocated as a means to improve incomes, livelihoods and the sustainability of smallholder farmers. This study analyzes the impact of commercial vegetable cooperative membership on smallholder agricultural performance in Cambodia. Institutional heterogeneities are considered across cooperatives and various econometric techniques are used to control for potential selection bias. The impacts of horticulture on agricultural outcomes are also analyzed. The results indicate that membership of commercial vegetable cooperatives has so far had no effect on agricultural incomes or the value or amounts of agricultural inputs. However, results indicate that membership has affected technology choice, access to credit services and information transmission through technological training. Additionally, there is evidence that horticulture, as a component of overall agricultural diversification, can augment farm income. The results suggest that much of the benefit of cooperative membership stems from the cooperative's provision of services, which might not be easily inferred from measures of member incomes.  相似文献   
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Water is a salient issue in the Intermountain West of the United States (U.S.), with concerns ranging from water scarcity and drought to intermittent flooding and water quality risks. This paper investigates coverage of water issues across seven newspapers in the core of the U.S. Intermountain West region. Newspapers have the potential to set agendas and influence perceived salience of issues among consumers. The Intermountain West region shares common concerns about water supply and demand, climate change, and water quality. We investigate whether or not local daily newspaper coverage of water issues provides a more local or regional sensitivity. Findings from this exploratory study reveal differences in water coverage across local daily newspapers. The overall volume of water‐related articles differed across newspapers as did proportion of articles on specific water topics and connecting issues. Coverage of local issues was more dominant than might be expected given mass media trends, but water geography in articles extended across the U.S. and the world in every newspaper studied. Variations in newspaper coverage of water issues suggests more local nuance persists despite the experience of common water issues across the region.  相似文献   
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Accurate estimation of evapotranspiration (ET) is essential to improve water use efficiency of crop production systems managed under different water regimes. The Agricultural Policy/Environmental eXtender (APEX) model was used to simulate ET using four potential ET (ETp) methods. The objectives were to determine sensitive ET parameters in dryland and irrigated cropping systems and compare ET simulation in the two systems using multiple performance criteria. Measured ET and crop yield data from lysimeter fields located in the United States Department of Agriculture‐Agricultural Research Service Bushland, Texas were used for evaluation. The number of sensitive parameters was higher for dryland (11–14) than irrigated cropping systems (6–8). Only four input parameters: soil evaporation plant cover factor, root growth soil strength, maximum rain intercept, and rain intercept coefficient were sensitive in both cropping systems. Overall, it is possible to find a set of robust parameter values to simulate ET accurately in APEX in both cropping systems using any ETp method. However, more computation time is required for dryland than irrigated cropping system due to a relatively larger number of sensitive input parameters. When all inputs are available, the Penman–Monteith method takes the shortest computation time to obtain one model run with robust parameter values in both cropping systems. However, in areas with limited datasets, one can still obtain reasonable ET simulations using either Priestley–Taylor or Hargreaves. 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   
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Food and Environmental Virology - The availability of drinking water is one of the main determinants of quality of life, disease prevention and the promotion of health. Viruses are important agents...  相似文献   
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An in‐well sediment incubator (ISI) was developed to investigate the stability and dynamics of sediment‐associated microbial communities to prevailing subsurface oxidizing or reducing conditions. Herein we describe the use of these devices at the Old Rifle Uranium Mill Tailings Remedial Action (UMTRA) site. During a seven‐month period in which oxidized Rifle Aquifer background sediment (RABS) were deployed in previously biostimulated wells under iron‐reducing conditions, cell densities of known iron‐reducing bacteria, including Geobacteraceae, increased significantly, showing the microbial community response to local subsurface conditions. Phospholipid fatty acid (PLFA) profiles of RABS following in situ deployment were strikingly similar to those of adjacent sediment cores, suggesting ISI results could be extrapolated to the native material of the test plots. Results for ISI deployment with laboratory‐reduced sediments showed only slight changes in community composition and pointed toward the ability of the ISI to monitor microbial community stability and response to subsurface conditions. © 2009 Wiley Periodicals, Inc.  相似文献   
66.

Improved agricultural practices that increase yields and preserve soils are critical to addressing food insecurity and undernutrition among smallholder farmer families. Urine-enriched biochar has been shown to be an accessible and effective fertilization option in various subtropical countries; however, it is new to Bangladesh. To better understand attitudes and experiences preparing and using urine-enriched biochar fertilizer, mixed-methods research was undertaken among smallholder farmers in northeastern Bangladesh in 2016/2017. In-depth interviews were conducted with 25 respondents who had compared the production of crops grown with biochar-based fertilizer to usual practice. In addition, in areas where trainings on biochar-based fertilization had been offered, 845 farmers were asked about their experience through a quantitative survey. Interview results indicated that cow urine-enriched biochar was favored over human urine because cow urine was perceived as clean and socially acceptable, whereas human urine was considered impure and disgusting. Respondents praised biochar-based fertilizer because it increased yields, cost little, was convenient to prepare with readily available natural materials, produced tastier crops, and allowed families to share their larger yields which in turn enhanced social and financial capital. Comparative field trials indicated a 60% yield benefit in both cabbage and kohlrabi crops. Challenges included uneven access to ingredients, with some respondents having difficulty procuring cow urine and biomass feedstock. The low social, health, and financial risk of adoption and the perceived benefits motivated farmers to produce and apply biochar-based fertilizer in their gardens, demonstrating strong potential for scale-up of this technology in Bangladesh.

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The administration of Jiuzhaigou National Park in Sichuan Province, China, is in the process of considering a range of upgrades to their sanitation and wastewater treatment systems. Their case history involves an ongoing series of engineering design flaws and management failures. The administration of the Park identified sustainability, environmental protection, and education goals for their sanitation and wastewater treatment system. To meet the goal of sustainability, environmental and economic concerns of the Park’s administration had to be balanced with socio-cultural needs. An advanced reconnaissance method was developed that identified reasons for previous failures, conducted stakeholder analysis and interviews, determined evaluation criteria, and introduced innovative alternatives with records of successful global implementations. This evaluation also helped the Park to better define their goals. To prevent future failures, the administration of the Park must commit to a balanced and thorough evaluation process for selection of a final alternative and institute effective long-term management and monitoring of systems. In addition, to meet goals and achieve energy efficient, cost-effective use of resources, the Park must shift their thinking from one of waste disposal to resource recovery. The method and criteria developed for this case study provides a framework to aid in the successful implementation of sanitation projects in both underdeveloped and developed areas of the world, incorporating socio-cultural values and resource recovery for a complex group of stakeholders.  相似文献   
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