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351.
《Geoforum》2017
Canada is in a liminal space, with renewed struggles for and commitments to indigenous land and food sovereignty on one hand, and growing capital interest in land governance and agriculture on the other. While neoliberal capital increasingly accumulates land-based control, settler-farming communities still manage much of Canada’s arable land. This research draws on studies of settler colonialism, racial hierarchy and othering to connect the ideological with the material forces of settler colonialism and show how material dominance is maintained through colonial logics and racially ordered narratives. Through in-depth interviews, I investigate how white settler farmers perceive and construct two distinctly ‘othered’ groups: Indigenous peoples and migrant farmers and farm workers. Further, I show the disparate role of land and labour in constructing each group, and specifically, the cultural and material benefits of these constructions for land-based settler populations. At the same time, settler colonial structures and logics remain reciprocally coupled to political conditions. For instance, contemporary neoliberalism in Canadian agriculture modifies settler colonial structures to be sure. I argue, however, that political economic analyses of land and food production in Canada (such as corporate concentration, land grabbing and farm consolidation) ought to better integrate the systemic forces of settler colonialism that have conditioned land access in the first place. Of course, determining who is able to access land—and thus, who is able to grow food—continues to be a territorial struggle. Thus, in order to shift these conditions we ought to examine how those with access and control have acquired and maintained it. 相似文献
352.
《Marine Policy》2017
This paper suggests that detrimental effects of certain neoliberal fisheries policies are key drivers behind the development of alternative seafood marketing programs in North America. It examines the structures, market and non-market values, and challenges of these programs. The primary aim of the research, based on interviews involving 20 programs and a conference workshop, was to advance understanding of the market value of alternative seafood marketing to fishers and communities. However, the importance of a broader set of non-market values was repeatedly highlighted by those engaged in these programs. Overall, the research suggests that alternative seafood marketing can enable fishers to participate in fisheries managed by neoliberal, market-based policies, through the promotion of market values along their diverse value chains. At the same time, alternative seafood marketing appears to resist market-based fishing systems, sometimes through the promotion of broader, non-market outcomes. Common challenges along these alternative seafood value chains highlight the structural conflicts that exist while simultaneously participating in and resisting neoliberal fisheries structures. 相似文献
353.
我国农田土壤碳库演变研究:全球变化和国家粮食安全 总被引:99,自引:0,他引:99
《京都议定书》已于2005年生效,我国面临着CO2减排的巨大压力。分析了我国农业土壤有机碳库及其演变研究的现状,认为当前我国农业在耕地资源严重短缺、耕地地力趋于下降的背景下面临着2个巨大挑战:提高和稳定粮食生产能力与补偿日益增加的工业CO2排放。有机碳贫乏作为我国耕地土壤的基本特点,这一方面提供了我国较大的固碳空间,另一方面也体现了我国实施固碳农业的必要性和紧迫性。目前迫切需要了解我国农业土壤在最近20年来的碳库演变态势与规模,明确我国农业土壤的固碳潜力与容量,在国家层面上实施农业固碳稳产工程,以在农业可持续发展和争取国家CO2排放的较大配额上实现双嬴。 相似文献
354.
355.
Biomagnification in marine systems: the perspective of an ecologist 总被引:14,自引:0,他引:14
Gray JS 《Marine pollution bulletin》2002,45(1-12):46-52
Biomagnification is the process where xenobiotic substances are transferred from food to an organism resulting in higher concentrations compared with the source. It is widely believed that this is a general phenomenon for marine food webs. An analysis of 148 papers with biomagnification in the title shows that under half show biomagnification. Of studies on metals only organic mercury shows biomagnification and most metals are regulated and excreted and do not biomagnify. Of the studies on organic compounds 67% claimed to show biomagnification. However, bioconcentration (uptake from the surrounding water) is the most usual way that organic compounds are accumulated in organisms from invertebrates to and including fish. Only in sea-birds and marine mammals is food intake the major route and where biomagnification can be clearly shown. Body concentrations of organic compounds vary with lipid content and thus in order to compare across species normalisation to uniform lipid content should be done. Yet often this is not done so data purporting to show biomagnification merely relate to differing lipid content in the different species studied. Finally suggestions are made as to how data can be collected to better interpret the process of biomagnification in marine food webs. 相似文献