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101.
ABSTRACT

Potential biofuel demand in South Africa is estimated to increase to 1550 million litres by 2025 due to mandatory blending rates. Land and water constraints, however, limit the ability for domestic production. Zambia, due to its abundance in land, suitable climate, supportive set of bioenergy incentives and close geographical location to South Africa, has the potential to meet this increase in demand. Using a dynamic recursive computable general equilibrium model, we estimate the macro- and socio-economic impacts of bioethanol production in Zambia from three potential crops: sugarcane, cassava and sweet sorghum. The results show that the development of a single product bioethanol industry has the potential to increase economic growth without negatively affecting overall food security. Further expansion of the industry to multiple products results in larger gains to growth and welfare.  相似文献   
102.
松嫩平原自然宜垦性及耕地后备资源开发潜力   总被引:1,自引:0,他引:1  
[目的]为保障我国粮食安全,为耕地后备资源的合理开发利用提供科学依据,同时完善中国区域耕地后备资源自然开发潜力方面的研究。[方法]文章从自然适宜性的角度出发,选取了地形、气候、土地类型和土壤4个方面15个评价因子,采用层次分析、专家打分等方法确定评价因子权重,构建松嫩平原宜垦性评价指标体系。[结果](1)1980—2015年松嫩平原自然宜垦性整体较好,最适宜垦区与较适宜垦区占松嫩平原面积的5068%,分布在松嫩平原腹地大部地区,中部、中北部、中南部等地;(2)松嫩平原已开垦耕地资源中,持续利用耕地占松嫩平原面积的4814%,空间上与宜垦程度高值区高度吻合;(3)新增耕地占区域面积的126%,以中度适宜垦区和较适宜垦区为主;(4)松嫩平原耕地后备资源占松嫩平原土地面积的1556%,在松嫩平原西部地区、中部和东北部地区均有分布,耕地后备资源中度及以上宜垦区占后备资源总量的7465%。[结论]目前大庆市和白城市可开发耕地后备资源最为丰富,但其中轻度及不适宜开垦区所占比例大,开发难度较大; 松原市可开发资源相对丰富且开垦难度小。  相似文献   
103.
Empowering women farmers to participate in agricultural research is a key strategy for sustainable agricultural development. Women empowerment has the potential to improve their roles in agricultural production while enhancing nutrition and food security. Although new agricultural development policies are focusing on improving women engagement in agriculture, there is limited literature on women empowerment in relation to agricultural research. This study used mixed methods to analyse women farmers’ participation in four stages of the agricultural research process – design, testing, dissemination, monitoring and evaluation. Two hundred and thirty individual interviews with women farmers and 16 focus group discussions with men and women farmers were conducted in four Woredas (districts) of Ethiopia. Quantitative data were analysed using binary and multivariate probit models. Qualitative data were analysed using line-by-line coding. The results showed that several empowerment indicator variables significantly (p?≤?.001) influenced women’s participation in different stages of agricultural research. Specifically, input in production decisions, autonomy in plot management, membership to farmer groups, and ability to speak in public enhanced women’s participation in different stages, in addition to access to information and extension services, education and land size. Cultural norms hindered women’s empowerment and engagement in research. To foster sustainable agriculture development, it’s important to integrate holistic and proactive gender perspectives into research strategies to increase women’s participation in farmer research groups, access information and knowledge, have voice and challenge constraining cultural norms and traditions.  相似文献   
104.
In Maasai culture, responsibilities are traditionally divided between genders. Men are in charge of grazing and managing the livestock herds. Women take care of the family, administer food supplies, and are responsible for milking. For them, balancing home consumption of milk (for the family and for the calves), milk sale, and food purchase is a major task. In this article, we first investigate how different milk sales groups vary regarding the use of different food items and the respective quantities consumed by the enkaji, i.e., a Maasai subhousehold. Then, we address the commercialization decision and assess the effect of milk sales on the enkaji's food item use and food consumption. Using the data of Maasai enkajijik in the milk catchment area of a milk collection center in Ngerengere, Tanzania, we estimate the effects by employing propensity score matching procedures. Our findings suggest that milk sellers, especially those selling to the milk collection center, have a more diverse diet. In terms of per person consumption, the groups are markedly similar. Therefore, we conclude that income generated by milk sales is invested in diet diversification rather than in increasing the quantity of food consumed, hence the enkajijik appear not to make use of caloric terms of trade.  相似文献   
105.
Self‐provisioning has long been an important component of urban political economic processes. However, it has recently become a central feature of grassroots urban governance strategies as well. In tumultuous cities of the twenty‐first century, with governments either unwilling or unable to effectively enforce zoning laws, police neighborhoods or manage infrastructure, some householders have begun performing these services instead. This article examines one subset of self‐provisioning practices that has emerged in southwest Detroit where residents have taken steps to secure abandoned housing as a means of exerting social control over their living environment. These actions embody many contradictions and ethical dilemmas, and the intimate scale of action has left the structural production of disinvestment in places like Detroit largely unchecked. Nevertheless, these guerilla‐style spatial interventions have emerged as critically important response strategies helping residents reduce their vulnerability and stabilize their blocks even as other nearby areas continue to experience decline.  相似文献   
106.
ABSTRACT

Industrial heritage valorizations are usually characterized by two pervasive trends: Firstly, there is an understandable, but extremely narrow, focus on national histories of industrialization, thus excluding what has always been a constitutive element of any industrialization path after the initial industrial revolution in England: transboundary flows of hardware, capital, knowledge, people or power. Secondly, there is an almost exclusive concentration on the individual achievements of entrepreneurs, engineers and architects in times of peace and industrial progress. Current industrial heritage valorizations only rarely adequately reflect the other side of industrialization phases or patterns, that is, their disquieting stories of war, occupation, other forms of imposed foreign influence, disasters, social unrest and the suffering of individuals or groups triggered by, or leading to, crises, failures, relocations and destruction. Taking these blind spots as its starting point, this paper explores more inclusive ways of representing industrial heritage. Based on the concept of geo-historically entangled processes of transnationalization and case studies from Germany and China, the authors argue that the industrial landscapes reflect both former and current transboundary industrialization processes representing two or more nations’ painful and dissonant, but common, heritage. This should be mirrored more appropriately and consistently in industrial heritage tourism approaches and interpretation strategies.  相似文献   
107.
通过对2000—2012年咸阳市产业结构和经济增长关系进行实证研究,结果表明:这一期间,对咸阳市经济增长拉动作用最大的是第二产业,产业每增长1%会引起GDP增长0.524%,第二产业对经济增长的贡献要明显高于全省整体水平,第一产业稍低于全省水平,第三产业则明显低于全省水平。未来在继续壮大第二产业的同时,更应该深挖咸阳自身的资源优势,抓住大西安建设的历史机遇,加快现代农业和第三产业的发展速度。  相似文献   
108.
Soil is a natural resource essential to human welfare by virtue of its numerous crucial functions. In the past, soil has been taken for granted because of its widespread, albeit finite, availability. However, now that world's population is projected to exceed ten billion before the end of this century, soil is increasingly perceived as a precious commodity. Consequently, soil is increasingly under pressure by rich private investors and governments within the poorest countries to satisfy appetites for food production and biofuel. A case study is used to explore the plausibility of soil being considered as ‘brown gold’. Based on the comparison of land use maps, we estimated the value in terms of resource from raw material, carbon sink and virtual calories of the productive soil lost during the period 2003–2008 in the Emilia-Romagna Plain, one of the most productive areas of Italy. More than fifteen thousand hectares of cropland underwent land use change – in particular urbanization – over the 6-year period with an implied loss of crop production potential equivalent to the daily calorific requirement of more than 440,000 people. Taking into account that Italy is no longer self-sufficient in food production, such a loss appears to be strategically significant. Perhaps more importantly, urbanization and soil sealing has had negative ramifications on environmental sustainability, on both local and broad scales, with increased consumption of public funds. A logical framework of the socio-economic impact of land use change has been compiled and is presented as a possible example of a policy relevant approach to managing productive soils as a finite resource.  相似文献   
109.
Lean working has had a significant impact on the work skills of civil servants. This study examines the impact of lean specifically focusing on ‘decision‐makers’, those civil servants engaged in deciding tax and social security claims. Using qualitative data from trade union members and stewards in two major government departments, this study found significant evidence of deskilling often in the face of dealing with potentially complex legal and factual issues. Using Mashaw's framework of administrative justice, the article argues that management's use of lean was evidence of an accelerated shift to a managerial model of administering tax and benefits where the administrative processes of decision‐making become paramount at the expense of the quality of the decisions made.  相似文献   
110.
东盟市场已经成为广西工业产品的主要出口市场,广西著名工业品牌、一般工业品牌、新创工业品牌在品牌知名度、产品质量、技术先进性、国际经营人才和经验等方面有较大差异,这些品牌所在企业在开拓东盟市场时"创建品牌"、"推广品牌"、"亮响品牌"、"伸展品牌"的路径和过程就不同,采取"单独开拓"、或"与文化产业联姻开拓"、或"与国内外品牌联姻开拓"的方式也有别,应针对不同品牌特性,采取不同的路径和对策,进一步拓展东盟市场,促进广西工业品在东盟市场的转型升级。  相似文献   
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