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101.
河北省主要农作物生产时空格局变化特征及安全评价   总被引:2,自引:0,他引:2  
曹永强  李维佳  袁立婷 《地理科学》2018,38(8):1319-1327
阐述主要粮食作物的时空格局变化特征,对中国粮食安全决策意义重大。基于河北省县市近15 a (2001~2015年)的农业数据资料,采用分段线性趋势以及生产指标-产量波动系数来分析河北省主要粮食作物的时空变化特征,并对河北省粮食作物进行安全评价。结果表明:从产量与播种面积来看,近15 a河北省主要粮食作物变化趋势经历了由波动减少到稳步增长2个阶段,且变化趋势显著;从空间格局变化来看,大致呈由南向北逐渐递减的规律分布,其中不同农作物分布规律各有差异;从粮食安全方面来看,河北省70%以上年份粮食波动系数均超过中国粮食安全平均水平,粮食波动系数较高,粮食安全风险较大;但从人均粮食产量来看,安全程度相对比较乐观,粮食安全状况渐趋于平稳。研究可为河北省粮食生产时空布局的优化、结构调整与社会经济协调发展提供依据。  相似文献   
102.
Food is essential for human survival, but harmful, toxic substances in food damage and threaten human health. Food production is inseparable from the place where the food is produced; that is, from the geographical environment that consists of natural and human environments, two parts of a unified whole. China’s territory is vast and its geographical environment is complex and diverse. Food production patterns in different parts of the country vary significantly, as do local socio-economic and cultural conditions. Such differences have an enormous impact on food safety. Based on the geographical area where food is produced in China, this paper reveals the main environmental problems arising from industrial and agricultural production activities, and related risks for food safety and health. In concluding, we make some recommendations for countermeasures. The main food safety related environmental problems include the excessive application of chemical fertilizers and pesticides; high background levels of heavy metals; discharge of wastewater and heavy metals; and excessive use of additives and antibiotics in livestock and poultry breeding and aquatic products. All these issues can lead to huge risks for food safety and thus health. These are not simply scientific issues, but also political, economic and legal issues, as well as social problems that differ from region to region. Therefore, comprehensive studies are needed to identify risks to food safety and health hazards in different areas. Systematic and comprehensive risk assessments of health problems caused by changing ecosystems, environmental pollution, nutrition problems and lifestyle, and especially comprehensive risk assessments of regional environmental changes and health risks are needed. Measures based on an understanding of local conditions must be put forward to protect food safety and health, to strengthen multi-sectoral management, and to improve environmental quality  相似文献   
103.
Environmental pollution, food safety and health are closely linked. A key challenge in addressing the problem of food safety and protecting public health is building an integrated knowledge base to inform policy and strengthen governance. This requires breaking down the trans-departmental information barrier across the environment, food and health domains to ensure the effective flow of data and the efficient utilization of resources, and facilitate the collaborative governance of food safety. Achieving this will be crucial for the development of health and medical care in China in the era of big data. Currently, the information resources commanded by various departments are incomplete and fragmented. Data resources are also organized in vertical silos and there is a lack of data sharing within and across policy streams. To provide the basis for more effective integrated collection and analysis of data in future, this study summarizes the information resources of various departments whose work relates to interactions between environment, food and health, and presents measures to strengthen top-down design, and establish unified data standards and a big data sharing platform. It also points to the need for increased training of data analysts with interdisciplinary expertise.  相似文献   
104.
This article investigates the sources of vegetables consumed by farmers, their perception of pesticide-related food safety risks and the behaviors they engage in to protect themselves, and explores the implications for the social co-governance (shehui gongzhi) of food safety emphasized by China’s recent Food Safety Law. The research site is a county in Yunnan Province where vegetable growing is the major source of income and livelihood for local farmers. We surveyed 417 farmers and collected 776 vegetable samples from 377 surveyed farmer households and tested them for organophosphate and carbamate pesticide residues using PR-12N Rapid Detection Instrument for Pesticide Residues. The results showed that farmers know about the risks to food safety caused by pesticides used in vegetable growing and they purposely avoid these risks by mainly consuming vegetables planted in home gardens or private plots that use little or no pesticides. Vegetable samples from these private plots had the lowest positive rate of pesticide residues (6.10%), compared with vegetable samples from commercial farmland (13.73%) and markets (12.66%), and the difference was statistically significant (X2=9.69,0.005相似文献   
105.
Farmers are both the producers and consumers of food, and as such have a dual role in food safety: they both generate risks and are exposed to them. Based upon a survey of the food production and consumption habits of 140 farm households and long-term research in two villages in Yunnan province, this study found that rural families are highly dependent on the market for food production and consumption. In their role as consumers, farmers are aware of food safety risks and concerned about them, but their ability to protect themselves is limited. They do so primarily by avoiding certain products and growing as much of their own food as possible. At the same time, in their role as producers, farmers engage in practices, primarily the overuse and inappropriate use of fertilizer and pesticides, that are damaging to food safety and the environment. There is therefore a disconnect in their roles as consumers and producers that needs to be addressed if policy goals for improving food safety and reducing the use of agricultural chemicals are to be achieved. Farmers need more information about food safety risks related to the products they consume themselves, and technical guidance on the safe use of farm chemicals when growing food for market. However, such measures will not be effective unless the external pressures on farmers are also addressed, through consideration of market incentives to use farm chemicals and the impact of consumer demand.  相似文献   
106.
Food security and sustainable agricultural development are the hot issues of scientific research, especially after the population affected by hunger surprisingly increased in 2016. Long-lasting and recurrent famines caused by natural disasters and wars have afflicted Ethiopia. Unlike Ethiopia, which is still struggling to achieve food self-sufficiency, China managed to quickly become food self-sufficient at a rapid speed, despite the fact that it also faced the same challenges of famine over the last century. In the backdrop of differing environmental and socio-political challenges the two countries face, comparing the similarities and differences between the two countries will yield important lessons and insights for Ethiopia to follow to achieve food self-sufficiency. Here, the progress towards food security in Ethiopia and China is presented to quantitatively compare the gap of agricultural production between both countries. We found that food production in Ethiopia is heavily constrained by drought, soil degradation, climate change, out-dated agricultural production technologies, and poverty. According to these challenges, we examined corresponding responses in China to propose solutions for achieving food self-sufficiency in Ethiopia, given the realities of its unique national situation.  相似文献   
107.
This paper offers a systematic analysis of the concepts and contexts that frame the climate-smart agriculture (CSA) discourse in the academic and policy literature. Documents (n?=?113) related to CSA and published in peer-reviewed journals, books, working papers, and scientific reports from 2004 to 2016 were reviewed. Three key trends emerged from the analysis: studies are biased towards global policy agendas; research focuses on scientific and technical issues; and the integration of mitigation, adaptation, and food security (the three pillars of CSA) is becoming a popular scholarly solution. Findings suggest that CSA is a fairly new concept used to describe a range of adaptation and mitigation practices without a specific set of criteria. Although CSA is often framed around the three pillars, the underlying issues constructing the discourse differ at global, developing, and developed country scales. Although there is increasing research on developing countries, particularly in relation to how CSA can transform smallholder agriculture, there is a paucity of research documenting the experiences from developed countries. The findings suggest that research on CSA needs to move beyond solely focussing on scientific approaches and only in certain geographical contexts. If CSA is to be applicable for farmers across the globe, then cross-disciplinary research that is underpinned by broad socio-economic and political contexts is essential to understand how differences in narratives might affect implementation on-the-ground in both developing and developed countries.

POLICY RELEVANCE

Although policy makers are increasingly supportive of the climate-smart agriculture (CSA) approach, the rhetoric has largely been developed on the basis of scientific and technical arguments. The political implications of varying perspectives have resulted in a growing divide between how developing and developed countries frame solutions to the impacts of climate change on agriculture under the 2015 Paris Agreement. Different framings are part of the explanation for why the scope of CSA is being rethought, with the scientific community redirecting attention to seeking a separate work programme under the United Nations Framework Convention on Climate Change (UNFCCC). The current policy framing of CSA will give no new policy direction unless it grounds itself in the smallholder farmer and civil society contexts.  相似文献   
108.
Fast food restaurants and liquor stores—vice stores—have been shown to be more prevalent in predominantly Black and low income U.S. neighborhoods, and are associated with a number of health risks and social ills. The purpose of this study was to investigate in the City of Chicago vice store density and spatial distribution as a function of racial, socioeconomic, and other population characteristics; to examine spatial clustering among these outlets; and to study how store turnover follows population change over a 13-year period. We used spatial point process analysis to fit linear and non-linear models for the intensity function of stores. Spatial clustering was estimated using the K function. We found heterogeneous associations between stores and population characteristics, with the most consistent finding being a positive association between percent Black and liquor store exposure. A high degree of spatial clustering was evident, and liquor stores were more likely to stay in business over time than fast food restaurants. However, when liquor stores closed, they were more likely to be replaced by non-vice businesses. Results suggest that vice stores are associated with lower positions in racial and socioeconomic hierarchies, and this patterning is often durable over time.  相似文献   
109.
Urban agriculture and the sustainability fix in Vancouver and Detroit   总被引:1,自引:1,他引:0  
Both Vancouver, British Columbia, and Detroit, Michigan, have significant and growing urban agriculture movements. In this article, I follow recent work investigating the connection between urban agriculture and neoliberalization to determine how these local governments have used urban agriculture in narratives of economic development to selectively pursue a sustainability fix. I analyze how different regimes of local governance have influenced the urban agriculture movements, leading to local, hybridized fixes that adapt to different material and discursive contexts in each place. I argue that in both cities, urban agriculture has radical potential as a grassroots response to economic and environmental injustice, but has also been enrolled as a device by the local state in which the primary goal of sustainability planning becomes enhanced economic competitiveness. Pursuing an agenda of food justice requires examining the larger context and effects of municipal involvement with food movements.  相似文献   
110.
2014年12月和2016年3月分别对热带西太平洋Y3海山(中层海山)和M2海山(浅海山)微食物网主要类群(包括聚球藻、原绿球藻、微微型真核浮游生物、异养细菌和浮游纤毛虫)丰度和生物量垂直分布进行了研究。结果表明,Y3和M2海山水文环境比较相似但略有区别,叶绿素最大值层(DCM)分别在75—100m和110m水层,微食物网各主要类群在垂直尺度上的分布与叶绿素a浓度紧密相关。其中浮游纤毛虫呈现"双峰型"模式,即丰度高值出现在表层和DCM层;原绿球藻和微微型真核浮游生物呈现"单峰型"模式,丰度高值出现在DCM层;聚球藻和异养细菌峰型相对不显著,DCM层以浅丰度较高,DCM层以深丰度明显降低。分析其原因,可能是受到温度、光照和营养盐的共同影响。Y3和M2海山微食物网结构的垂直变化不完全一致。其中,Y3海山30m以浅和150m以深异养细菌生物量占绝对优势,75—100m水层自养型生物(原绿球藻和微微型真核浮游生物)占绝对优势;M2海山75m以浅和200m以深异养细菌占绝对优势,110—150m自养型生物占绝对优势。M2海山自养型生物占优势的水层要明显深于Y3海山,可能与它们的海山类型和采样季节不同有关。  相似文献   
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