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1.
This paper examines the nexus between milk production and water use in India. The nexus is examined in the context of extended consumptive water use (CWU) of milk production beyond drinking water. It includes the real CWU (evapotranspiration (ETa) that occurs during the production of green fodder and feed grains) and the virtual CWU (ETa embedded in by-products for animal feed). The real CWU appears as large as that of sugarcane, and the real and virtual CWU combined is as large as that of rice. However, milk production generates more value than the outputs of rice and sugarcane combined. Sustainable water use and agricultural growth in major milk-producing areas require a drastic reduction in groundwater CWU, which, at present, exceeds natural recharge. It is suggested that diversifying to a mix of milk and high-value (but low water consuming) crops can reduce groundwater CWU while ensuring higher total output.  相似文献   

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With the decline of cotton especially in the marginal cotton areas, farmers have been using more of the cotton‐financed inputs on the cereals. The cotton para‐statal company (CMDT) has made a virtue out of this recommending diversification for these regions. Following the world price spike in 2010, the Malian government responded with a substantial price increase for cotton in 2011 of 38% to rejuvenate the Malian sector. This article looks at the impact of this price policy in the cotton economy and the potential of new cereal technology and marketing strategy to raise incomes and facilitate the diversification. Given the importance of the marketing decision of selling later after the recovery of cereal prices from the harvest collapse, a discrete stochastic programming model was developed for three‐stage decision making. Then, the recent changes in the cotton economy and government fertilizer subsidies were analyzed along with the introduction of the new technology marketing of sorghum. Cotton and maize continue to dominate the economy but the combined sorghum technology marketing increases farmers’ incomes by 16% to 21% and eases the return to normal cotton prices, after the 2011 price spike, as well as the removal of the fertilizer subsidies.  相似文献   

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本文通过对讷河国家气象观测站近35a(1981-2015年)的地面观测资料(温度、降水、积温、日照、无霜期)进行整理,运用统计分析的方法查找出近35a讷河市光、热、水气候资源变化规律.结果表明:讷河市热量资源(气温和积温)总体呈上升趋势,气温每10年上升0.445℃,≥10℃积温总体呈上升趋势,无霜期延长;水资源(降水量)波动存在一个3-5年的变化周期;光资源(日照时数)季变化按照春季-夏季-秋季-冬季递减,年代变化线性趋势略呈减少.  相似文献   

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本文以武汉沙湖水体为研究对象,以“3S”技术为支撑,基于Landsat 8遥感影像数据与实测水质数据,根据各波段反射率的相关性,分析与研究了遥感影像数据的适宜波段,采用回归分析的方法,建立适合沙湖水体的叶绿素a浓度遥感反演模型。反演结果表明,以第4波段建立的多项式回归反演模型效果较好,其平均误差为7.28%,Landsat 8影像数据能有效用于沙湖叶绿素a浓度的监测,在空间分布上也呈现一定的空间格局形态,并显示沙湖西北角(新生路泵站)污染相对严重,与沙湖实际情况基本吻合,因此将Landsat 8影像数据应用于内陆湖泊水体叶绿素a浓度反演具有一定的可行性。  相似文献   

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This study suggests UK equivalent variation (EV) gains of €8.9 billion on withdrawal from the EU budget. Factoring in associated trade facilitation costs from the loss of UK access to the single market, annual UK EV losses could be as high as €14.0 billion, with the EU‐28 facing a corresponding loss of €40.4 billion. Interestingly, the extrapolated UK gain arising from withdrawal from the ‘CAP’ component of the EU budget exceeds estimated lower and upper bound trade facilitation costs exclusively on EU agrofood trade. Accordingly, the UK should realistically remain as an EU member, although continue to lobby for reductions in the CAP budget.  相似文献   

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During the Trump administration, there has been an unprecedented increase in the level of domestic support provided to US agricultural producers. Direct farm supports, including price and income support payments, federal crop insurance, and supplemental assistance to compensate losses due to the trade war with China and the pandemic, have accounted for more than one‐third of net farm income. Those payments have threatened to push the United States over its World Trade Organization (WTO) domestic support obligations and increased its vulnerability to potential dispute settlement challenges in the WTO. The incoming Biden administration will likely bring a new focus to repurpose farm subsidies to provide environmental benefits, such as reduced greenhouse gas emissions, but to achieve those reforms they will need to convince a US Congress that has historically been prone to maintaining the status quo.  相似文献   

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Food deserts and their potential effects on diet and nutrition have received much attention from policymakers. While some research has found a correlation between food deserts and consumer outcomes, it is unclear whether food deserts truly affect consumer choices. In this article, we compare food prices in food deserts, defined as low‐income, low‐access census tracts, and nonfood deserts to observe whether and to what extent consumers face higher prices for a complete diet in food deserts. If a nutritionally complete diet costs significantly more in food deserts, resident consumers may be constrained from consuming healthier foods. We use store‐level scanner data from a nationally representative sample and calculate a census‐tract level Exact Price Index (EPI) based on a food basket defined by the Thrifty Food Plan (TFP). The EPI addresses potential biases from both product heterogeneity and variety availability. We find that the overall price impact of living in a food desert is small; low‐access areas have only 3.5% higher EPI than high‐access counterparts. However, consumers who are constrained to shop within their own census tracts face a much higher EPI than high‐access counterparts (9.2%). The higher EPI primarily comes from lower variety availability in food deserts.  相似文献   

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This paper makes use of the income variability generated by the macroeconomic crisis of 2001/2002 to examine schooling outcomes in Argentina. The effect of this macroeconomic swing is examined with a focus on whether the income or substitution effect dominates in the decision-making of young people. It is demonstrated that the probability of being in school was 6.5–10 percentage points higher in May 2002 than in 2001 for 15–18-year-olds. This is probably the largest (positive) effect found in the developing country literature so far and is comparable to the effect of a 10% increase in household income. For 19–25-year-olds, the probability is between 2 and 6 percentage points higher. Results are robust to a wide range of controls and specification checks. Difference-in-difference panel estimation corroborates these findings and shows that the increase in schooling seems to be driven by a decrease in school exits during the crisis.  相似文献   

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Rotational grazing has been promoted as a best management practice with environmental benefits and associated higher revenue. Its adoption rate has been relatively low. This study investigates the role of uncertainty in the adoption of rotational grazing with a cost‐share by cattle producers. Mail survey results indicate that 63–71 per cent of cattle producers are uncertain about adoption with a government cost‐share. The study suggests that the possibility of uncertainty should be considered in cases where willingness‐to‐pay is elicited in the context of adoption of technology.  相似文献   

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Genuine savings is a conceptually valid one‐sided indicator as to whether Australia is on a weak sustainability path (negative GS would warn that current welfare is unsustainable). The World Bank's adjusted net savings (ANS) data summarise the available evidence, and by this indicator Australia is muddling along, at best. ANS misses some important pieces of the picture – net depletion of water, soil and biodiversity, and most kinds of pollution damage – and thus overstates Australia's genuine savings performance. Weak sustainability can be promoted by getting the prices right, and piecemeal efforts are underway via regulatory approaches and resource/environmental markets of various kinds. Nevertheless, particular resource problems – habitat conservation, biodiversity, climate change and dryland salinity – are likely to also require strong sustainability approaches. A sustainable future involves pushing weak sustainability as far as the body politic permits, invoking precautionary instruments for specific resource crises, and nurturing policy processes that encourage the consensus‐building that will be necessary to get it done.  相似文献   

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After 2008, China dairy industry has experienced a consolidation supported by the government mainly for the reason of food safety. Subsidies are one of the tools to shape a concentrated market with goals of reducing regulation cost and accomplishing quality control. This gives a serious concern that subsidies would generate a less competitive dairy industry. We construct a parametric model and use the firm‐level panel data, specifically the top eight dairy firms, to test if government subsidies strengthen the market power in the dairy industry. Our empirical results indicate government subsidies have a negative impact on the Lerner index for the top privately owned firms, but no significant effect on state‐controlled ones after controlling for advertising, time trend, and proprietorship. It is possible that the subsidies give more room for private firms to increase the scale or suppress the price, which eventually reduces the market power and benefits dairy customers in the downstream.  相似文献   

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From the perspective of China's trading partners, few policy issues are as important as China's emergence onto world agricultural markets. In this essay, we argue that if China is to become a modern developed country, a massive structural transformation of China's agricultural sector must occur. We offer a forward-looking vision of China's food economy and its links with the world in the 21st century. We believe that gains from specialization when China moves to a country with specialized family farms will be huge compared to the returns that have resulted from decollectivization. Following a structural revolution in China's agricultural sector, China will become a major force in world food markets. This transformation will be characterized by land reform, a massive shift of labor out of agriculture, expanded farm size, a significant change in regional cropping patterns, more interprovincial trade, and greater international trade. This structural transformation will occur as long as there is strong economic and political pressure to raise agricultural labor productivity, liberalize markets, boost the rule of law, and increase per capita farm incomes relative to urban incomes.  相似文献   

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Reconciling productive agricultural practices with nature conservation is not only an ecological challenge, but also a demanding matter of governance. This paper analyses the potential as well as the limitations of various governance arrangements, and explores ways to enhance the governance of nature conservation in agricultural landscapes. We assume four conditions to contribute to the performance of these arrangements: farmers should be motivated, demanded, enabled, and legitimized to participate in arrangements that promote nature conservation by farmers. We analyse 10 distinct Dutch governance arrangements in the period 2000–2016, including agri-environment schemes but also privately initiated arrangements. The arrangements target a large but unknown share of farmers and farmlands, but nature conservation ambition levels are generally low to moderate. The expected low-to-moderate performance is associated with a low-to-moderate motivation, demand, and ability. Underlying are stronger forces driving towards intensification and problems farmers face in recuperating the cost of nature conservation. New greening requirements in the EU Common Agricultural Policy and in agri-food supply chains are first, cautious steps addressing these fundamental drivers of ecological degradation. More ambitious greening requirements may contribute to a higher motivation and ability of larger groups of farmers to implement nature conservation measures.  相似文献   

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Although meat demand is one of the most studied issues in agricultural economics, our understanding of this phenomenon has been hampered by valid concerns about model specification uncertainty. This article revisits the need for more general theories of aggregate U.S. meat demand. Using a Bayesian averaging of classical estimates approach, we draw comprehensive inferences over 1,048,576 demand systems. We find very little evidence supporting the need for more general theories that include demand determinants beyond prices and expenditures. We find strong evidence in support of symmetry and negativity, but strong evidence against homogeneity, which is consistent with other research.  相似文献   

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西宁近48a来气温变化的多时间尺度分析   总被引:4,自引:0,他引:4  
利用Morlet小波分析了1954 ̄2001年西宁市年平均气温距平时间序列的小波变化特征,揭示了气温变化的多时间尺度结构,分析了其中存在的主要周期振荡和突变点,并与功率谱分析结果进行比较。结果表明:西宁市年平均气温存在多时间尺度的周期变化特征,西宁市年平均气温存在3.5a,准11a和准24a的主周期。西宁市的气温变化存在着明显的多时间尺度,即年代际尺度和年际尺度的周期性变化,20 ̄32a时间尺度具全域性外,其它尺度的局部化特征则很强。西宁市的气温变化还显示出突变点分布和及其位相结构。21世纪初西宁市年均气温还将处在一个偏冷期。通过功率谱和小波变换方法在诊断气温变化上的应用,得出功率谱在诊断气温变化中一些缺点,而小波变换方法能分析气温序列随时间变化的多层次结构,功率谱分析方法由于自身原因难以做到这一点。  相似文献   

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