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131.
Nadra Hashim 《Local Environment》2015,20(6):611-636
The Urban Farming Movement is relatively young in Louisville, Kentucky but it seems to be off to a good start. Being in its earliest stages, assessments of this effort must be made cautiously, even tentatively. Examining a movement that is in progress requires a study of the state's land use and segregation policies, both of which have been dynamic in Kentucky. Further, this study is also relevant as there is a growing convergence of national and regional attitudes towards American obesity, while there are competing notions of food preference and food choice. All of which are influenced by racial politics, and there is a deep concern regarding food security. Considering all of these, it is necessary to examine the Government's efforts to address obesity/food imbalance in a variety of settings, especially where urban farming is expanding, such as Chicago and Detroit. In New York, roof-top gardens dot the landscape and the urban farm movement is largely a “success”. So, city leaders have chosen to address another health issue – trans fat. Rather than joining the food choice/preference debate by banning fast-food restaurants, city leaders have chosen to enact a trans-fat ban. Unpopular at first, other cities and states have followed, and the Federal Government will mandate a trans-fat ban this year. In Louisville, Chicago and Detroit, where the trans-fat bans did not succeed, the urban farm movement may be the primary means of addressing malnutrition, in the form of obesity. 相似文献
132.
Amenity migration to attractive and accessible non-metropolitan areas changes social and environmental relations with consequences for natural resource management and landscape composition and trajectories. Lifestyler oriented rural landholders are often cast as a problem for land management and extension. Managers and some researchers see them as a cause of landscape and social fragmentation and report difficulties in engaging such landowners on natural resource management issues and responsibilities. In contrast, limited existing research indicates that lifestylers do join and form networks of personal and other contacts for advice and support in land management. We contribute to this research with a survey of rural landholders in southeastern New South Wales (NSW). We explicitly compare the sources of advice for land management for lifestylers with those of farmers. We focus on the types of sources available to rural landholders in Australian regions and their relative importance to these two landholder groups. We find that lifestylers and farmers are different in their sources of advice but that both prefer personal sources rather than sources such as agencies. We reflect on the significance of the differences for engagement with lifestyle oriented rural landowners and for understanding landscape change. 相似文献
133.
134.
Pluriactivity of farms, or part-time farming, is a common feature of agriculture in all countries regardless of their socioeconomic
system and level of development. Currently, pluriactivity is related to the values of sustainable agriculture. The objective
of this study is to delineate those specific characteristics of pluriactive farms that contribute to sustainable agriculture.
In rural areas of Boetia in Greece, a socioeconomic survey was carried out on 114 farms to determine the types of farming
applied. The results demonstrate that pluriactivity is a stable component of the agricultural structure in the rural areas
of Boetia. It is widespread in plains, but its presence is more important in mountainous and semimountainous areas. The choice
of young farmers is to opt for pluriactivity. Farm size does not differ between pluriactive and full-time farms. Pluriactive
and full- time farms use the same level of input and get the same output for the same type of crop. However, pluriactive farmers
under the same land-productive conditions are oriented toward a more extensive farming system, managing their land with crops
that need less inputs. Considering these findings, it can be claimed that pluriactivity can contribute to diminishing the
demand on natural resources in favored (level and irrigated) areas, to continue agricultural production in unfavorable (mountainous
and semimountainous) areas, and to help the sustenance of the rural population. 相似文献
135.
Natividad Aguilera-Alcal Eneko Arrondo Roberto Pascual-Rico Zebensui Morales-Reyes Jos M. Gil-Snchez Jos A. Donzar Marcos Molen Jos A. Snchez-Zapata 《Ambio》2022,51(5):1330
In recent decades, intensive techniques of livestock raising have flourished, which has largely replaced traditional farming practices such as transhumance. These changes may have affected scavengers’ behaviour and ecology, as extensive livestock is a key source of carrion. This study evaluates the spatial responses of avian scavengers to the seasonal movements of transhumant herds in south-eastern Spain. We surveyed the abundance of avian scavengers and ungulates, and analysed the factors affecting the space use by 30 GPS-tracked griffon vultures (Gyps fulvus). Griffons’ foraging activity increased in the pasturelands occupied by transhumant herds, which implied greater vulture abundance at the landscape level during the livestock season. In contrast, facultative scavengers were more abundant without transhumant livestock herds, and the abundance of wild ungulates did not change in relation to livestock presence. We conclude that fostering transhumance and other traditional farming systems, to the detriment of farming intensification, could favour vulture conservation.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01668-x. 相似文献
136.
Lindahl P Maquet A Hult M Gasparro J Marissens G González de Orduña R 《Journal of environmental radioactivity》2011,102(2):163-169
The distribution of natural radionuclides was studied in winter wheat plants collected from three sites in Belgium during 2004-2007. Activity concentrations of 40K, 226Ra, 228Ra and 228Th in organically and conventionally grown wheat, and in the corresponding soil samples, were determined using ultra low-level gamma-ray spectrometry. The observed soil-to-wheat concentration ratios were calculated for the different parts of the wheat plant (root, stem and grain) in the two agricultural systems (organic and conventional). There were large variations in radionuclide activity concentrations between the sites and fields, but no significant difference between conventionally and organically grown wheat plants was observed. 相似文献
137.
通过建立引入气候因素的种植业生产函数模型,利用1990-2009年山东省40个县市种植业生产及气象面板数据,运用产出增长分解法,实证分析气候因素和非气候因素对山东省种植业产出的影响并对产出增长的各要素贡献进行分解。结果表明:气候变暖对山东省种植业带来明显的负面影响。1990-2009年间气候因素对山东省40个县市的总体产出增长的影响为-11.03%,在其他条件不变的情况下,平均温度每升高1℃,总体种植业总产值减少2.2%,总体产值增长下降1.48%;温度升高对鲁西北地区、鲁南地区种植业产出的影响最为明显;同时,降水对种植业产出影响显著,降水因素使得山东省种植业产出增长减少16.86%;物质投入中化肥和农药对种植业产出增长贡献最大,但农业劳动力减少,特别是种植业劳动力的减少,开始显著地影响种植业产出,使得种植业产出增长减少5.90%;技术进步的影响作用在下降。 相似文献
138.
139.
Combination of multispectral remote sensing, variable rate technology and environmental modeling for citrus pest management 总被引:1,自引:0,他引:1
The Lower Rio Grande Valley (LRGV) of south Texas is an agriculturally rich area supporting intensive production of vegetables, fruits, grain sorghum, and cotton. Modern agricultural practices involve the combined use of irrigation with the application of large amounts of agrochemicals to maximize crop yields. Intensive agricultural activities in past decades might have caused potential contamination of soil, surface water, and groundwater due to leaching of pesticides in the vadose zone. In an effort to promote precision farming in citrus production, this paper aims at developing an airborne multispectral technique for identifying tree health problems in a citrus grove that can be combined with variable rate technology (VRT) for required pesticide application and environmental modeling for assessment of pollution prevention. An unsupervised linear unmixing method was applied to classify the image for the grove and quantify the symptom severity for appropriate infection control. The PRZM-3 model was used to estimate environmental impacts that contribute to nonpoint source pollution with and without the use of multispectral remote sensing and VRT. Research findings using site-specific environmental assessment clearly indicate that combination of remote sensing and VRT may result in benefit to the environment by reducing the nonpoint source pollution by 92.15%. Overall, this study demonstrates the potential of precision farming for citrus production in the nexus of industrial ecology and agricultural sustainability. 相似文献
140.
Nicholas P. Guehlstorf 《Journal of Agricultural and Environmental Ethics》2008,21(6):541-558
In the beginning, policy debates between critics and advocates of genetically modified (GM) crops focused on scientifically
determined risks. Ten years later, the argument between environmentalists or consumers and regulators or industry has changed
into a discussion about the implementation of more democratic policymaking about GM farming. A notable omission from the political
debate about food biotechnology in the United States, however, is the opinion of farmers who cultivate the GM crops. Policymakers
should value practical knowledge based on experiences from farmers, not only scientific industry reports or consumer product
opinions. This project uses in-depth interviews to create an original mail survey that uses the practical discourse of farmers
in order to explore the relationship of farmer attitudes and GM agriculture. Although national research indicates that larger
yields are the most common reason for GM adoption, qualitative information suggest that the potential of GM crops to increase
revenue per acre does not truly reflect all the concerns of modern farmers. For example, farmers who use GM seeds indicate
that they constantly question the social impacts of their agricultural practices. As such, GM policies should be restructured
as a political rationalization of both economic modeling and political theory because this research suggests that farmers’
business decisions are utility calucations that consider economics without ignoring environmental and political contexts.
Farmers’ concerns about non-economic risks suggest that they need more information about GM crops and that governmental policies
should respond to their interests, as they are more democratic or pluralistic than industry or consumer arguments. 相似文献