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61.
62.
《Food Policy》2019
Using three waves (2008/09, 2010/11, 2012/13) of the Tanzanian National Panel Survey, this study investigates the impact of maize price shocks on household food security. Between 2008/09 and 2012/13, calorie intake stagnated for urban households, yet sharply deteriorated for rural households. The latter was driven by a significant decline in the consumption of the major staple maize which showed strongest price hikes among all major food items. Fixed-effects regressions indicate a clear negative relationship between maize prices and average household energy intake. Almost all population groups were found to be negatively affected by maize price shocks, with rural landless households being the most vulnerable group. In particular, a 50 percent rise in maize prices decreases caloric intake for rural (urban) households on average by 4.4 (5.4) percent, and for rural landless households by 12.6 percent. Results further indicate that subsistence agriculture can act as an effective strategy to insure against food price volatility. 相似文献
63.
Faaiqa Hartley Dirk van Seventer Paul Chimuka Samboko Channing Arndt 《Development Southern Africa》2019,36(2):213-232
ABSTRACTPotential 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
64.
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5068%,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4814%,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126%,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1556%,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7465%。[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
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66.
Annet A. Mulema Wellington Jogo Elias Damtew Kindu Mekonnen Peter Thorne 《国际农业可持续发展杂志》2019,17(2):127-145
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
67.
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
68.
Kimberley Kinder 《International journal of urban and regional research》2014,38(5):1767-1784
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
69.
Do analysts who understand accounting conservatism exhibit better forecasting performance? 下载免费PDF全文
Jay Heon Jung Sonya S. Lim Jinhan Pae Choong‐Yuel Yoo 《Journal of Business Finance & Accounting》2017,44(7-8):953-985
This study investigates the performance of analysts when they match the asymmetric timeliness of their earnings forecast revisions (i.e., asymmetric forecast timeliness) with the asymmetric timeliness of firms’ reported earnings (i.e., asymmetric earnings timeliness). We find that better timeliness‐matching analysts produce more accurate earnings forecasts and elicit stronger market reactions to their forecast revisions. Further, better timeliness‐matching analysts issue less biased earnings forecasts, more profitable stock recommendations and have more favorable career outcomes. Overall, our results indicate that analysts’ ability to incorporate conditional conservatism into their earnings forecasts is an important reflection of analyst expertise and professional success. 相似文献
70.
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