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1.
With continually increasing demand for food accompanied by the constraints of climate change and the availability and quality of soil and water, the world’s farmers are challenged to produce more food per hectare with less water, and with fewer agrochemical inputs if possible. The ideas and methods of the system of rice intensification which is improving irrigated rice production are now being extended/adapted to many other crops: wheat, maize, finger millet, sugarcane, tef, mustard, legumes, vegetables, and even spices. Promoting better root growth and enhancing the soil’s fertility with organic materials are being found effective means for raising the yields of many crop plants with less water, less fertilizer, reduced seeds, fewer agrochemicals, and greater climate resilience. In this article, we review what is becoming known about various farmer-centred innovations for agroecological crop management that can contribute to agricultural sustainability. These changes represent the emerging system of crop intensification, which is being increasingly applied in Asian, African, and Latin American countries. More research will be needed to verify the efficacy and impact of these innovations and to clarify their conditions and limits. But as no negative effects for human or environmental health have been identified, making these agronomic options more widely known should prompt more investigation and, to the extent justified by results, utilization of these methodologies.  相似文献   
2.
Bovine Mastitis is one of the most prevalent and costly production diseases in the dairy industry in Canada and worldwide causing major animal welfare problems, environmental problems, and productivity losses. In this paper, we examine the effects of risk attitudes and social interactions on the willingness to pay (WTP) for genotyping animals for susceptibility to a chronic mastitis trait. We use contingent valuation with double bounded dichotomous choice questions to elicit producers’ WTP. The estimated mean WTP for genotyping is approximately $50 per animal. Compared to the current market prices of commercially available comprehensive genotyping services, this estimate suggests a significant market potential for genotyping to be bundled with economically important disease traits. We also find evidence that both risk attitudes and social interactions have strong effects on the WTP for genotyping. Farmers with higher risk tolerance are willing to pay more for genotyping service. For dairy farmers with more concern about mastitis, risk tolerance has no significant effect on the WTP, while social interactions have a significant effect on the WTP. We also find a strong interaction effect between risk tolerance and social interactions. The findings encourage interest in questions about how risk attitudes, social networks, and their interactions shape the adoption of and the WTP for a novel agricultural technology. La mastite bovine est la maladie de production la plus répandue et la plus coûteuse de l'industrie laitière au Canada et mondialement causant des problèmes en ce qui concerne le bien‐être des animaux, l'environnement et la perte de productivité. Cet article examine les effets de l'attitude à l′égard du risque et des interactions sociales concernant la volonté de payer pour le génotypage d'animaux pour le dépistage de la susceptibilité à posséder le trait de mastite chronique. L'évaluation contingente avec questions à double proposition dichotomique a été utilisée afin d'obtenir la volonté de payer des producteurs. La volonté moyenne estimée de payer pour le génotypage s'élève à approximativement 50 $ par animal. Comparée aux prix courants du marché pour les services commerciaux complets de génotypage, cette estimation suggère un potentiel commercial significatif pour grouper le génotypage à d'autres traits de maladie d'importance économique. Nous trouvons aussi trouvé que les attitudes à l′égard du risque et les interactions sociales avaient un impact significatif sur la volonté de payer pour le génotypage. Les fermiers démontrant une grande tolérance au risque sont disposés à payer plus pour les services de génotypage. Pour les producteurs laitiers préoccupés par la mastite, la tolérance vis‐à‐vis du risque n'a aucun effet sur la volonté de payer, tandis que les interactions sociales en ont une importante. Nous notons aussi un effet significatif d'interaction entre la tolérance pour le risque et les interactions sociales. Les résultats favorisent un questionnement au sujet des attitudes à l′égard du risque, des réseaux sociaux et de leurs interactions, cherchant comment ces derniers guideront l'adoption de nouvelles technologies agricoles et la volonté d'en acquérir.  相似文献   
3.
为配合多德弗兰克法案实施,美国证券交易委员会(sEc)、商品期货交易委员会(cFTc)等监管机构分别组织制“沃克尔法则”细则征求意见稿,此举引起各国政府和市场机构的广泛关注。文章概括了“沃克尔法则”细则征求意见稿中限制银行从事自营交易的主要内容,分析了其可能产生的潜在影响,整理了市场相关反应与评价,结合其对中资银行经营、特别是金融市场业务发展带来的影响与启示进行了分析和思考,并提出相关政策建议。  相似文献   
4.
莱钢现有的焦化废水经生化处理后COD等指标很难达到排放标准,随着干熄焦装备的投入使用及节能减排要求力度的不断加大,焦化废水面临着如何处理的难题。针对这种情况,对目前国内外有关焦化废水处理技术的研究与分析,结合实际情况,开发出一种新的焦化废水深度处理工艺,即采用生物脱氮与MBR、三相催化氧化处理相结合工艺,使处理后的水作为循环冷却水使用。  相似文献   
5.
The use by farmers of futures contracts and other hedging instruments has been observed to be low in many situations, and this has sometimes seemed to be considered surprising or even mysterious. We propose that it is, in fact, readily understandable and consistent with rational decision making. Standard models of the decision about optimal hedging show that it is negatively related to basis risk, to quantity risk, and to transaction costs. Farmers who have less uncertainty about prices and those with a diversified portfolio of investments have lower optimal levels of hedging. If a farmer has optimistic price expectations relative to the futures market, the incentive to hedge can be greatly reduced. And finally, farmers who have low levels of risk aversion have little to gain from hedging in terms of risk reduction, in that the certainty‐equivalent payoff at their optimal hedge may be little different than the certainty equivalent under zero hedging. These reasons are additional to the argument of Simmons (2002) who showed that, if capital markets are efficient, farmers can manage their risk exposure through adjusting their leverage, obviating the need for hedging instruments.  相似文献   
6.
Achieving sustainable food security and increased farm income will depend on how efficient production systems are in converting available inputs to produce outputs. Using data from Malawi, we estimate a Bayesian directional technology distance function to examine the relationship between farm size and technical efficiency. Our results support the existence of an inverse relationship between farm size and productive efficiency, where small farms are more efficient than large farms. On average, farms exhibit inefficiency levels of 60%, suggesting that productivity could be improved substantially. Improving productive efficiency and food security will require farms to operate in ways where the size of cultivated area is matched by nonland production inputs such as labor, fertilizer, and improved seeds. The results highlight the need for policies that could incentivize farmers to adopt productivity‐enhancing technologies and, where possible, to allocate excess land to lease markets.  相似文献   
7.
通过对不同粒级配合煤进行不同细度的配合炼焦试验研究,得出:当配合煤细度控制在77%时,所得焦炭综合指标质量较好,此时,焦炭显微强度58.49%、结构强度86.41%、焦炭反应性34.8%、反应后强度49.6%。  相似文献   
8.
This paper investigates the factors affecting the corn basis in Ontario with particular emphasis on the effect of ethanol production given the projected detrimental effect its expansion could have on the red meat sector. We estimate a location‐specific and panel vector error correction models (VECM) for seven elevators in Ontario from 2006 to 2013. We find a long‐run equilibrium relationship exists between the basis and factors affecting local supply and demand including ethanol capacity and that the direction of causality is from these factors to changes in corn price. A one‐time increase in ethanol capacity of 100 million liters is projected to increase the basis by approximately 30 cents per bushel within two years. However, the impact is insignificant for elevators located in the livestock‐intensive regions of the province. The demand for corn as livestock feed is a determinant of the local corn price for all elevators. The decline in the number of hogs and beef cattle along with the 50% increase in corn supply have resulted in the observed decline in the local corn price despite the significant increase in demand from ethanol. L'impact de la production locale d′éthanol sur le prix de base du maïs en Ontario Cet article cherche à comprendre les facteurs ayant un effet sur le prix de base du maïs en Ontario, en particulier sur les effets de la production d′éthanol étant donné les effets négatifs attendus sur le secteur de la viande rouge causés par son expansion. Nous estimons des modèles vectoriels à correction d'erreurs (MVCE) à emplacements précis et panel entre 2006 et 2013, pour 7 silos‐élévateurs en Ontario. Nous constatons une relation d′équilibre à long terme entre le prix de base et les facteurs ayant un effet sur l'offre et la demande locale incluant la capacité pour l′éthanol. Nous constatons aussi que le sens de la causalité passe de ces facteurs aux changements du prix du maïs. L'on s'attend à voir une augmentation d'environ 30 cents du prix de base du boisseau suivant l'augmentation unique de 100 millions de litres de la capacité d′éthanol. Par contre, l'impact est négligeable pour les silos‐élévateurs situés dans les régions d′élevage intensif de la province. La demande pour le maïs comme aliment pour le bétail est un facteur déterminant du prix local du maïs pour tous les silos‐élévateurs. Le déclin du porc et des bovins ainsi que l'augmentation de 50 % de l'offre de maïs ont mené à la diminution notée du prix du maïs local malgré l'augmentation significative de la demande pour l′éthanol.  相似文献   
9.
Rice has been identified as an important food security crop in Ghana. However, there is a production deficit and new technologies to reduce the deficit are not widely adopted. Although poor adoption by farmers’ is often linked to constraints such as access to information, farmers’ perceptions of the technologies are also important. We apply an advanced discrete choice experiment to evaluate farmers’ preferences for rice production practices. Specifically, we generate willingness to pay (WTP) estimates using willingness to pay space (WS) and compare these with values from the indirect or preference space (PS) method. Our modelling also accounts for the effects on WTP estimates of farmers’ stated attribute importance (SAI) information. Empirical results from WS and PS models reveal that on average, farmers value higher yields and are negatively affected by higher risk of crop failure and labour requirements. Comparing the performance of the two models, we find the WS model provides a superior fit to our data and reduces the likelihood of producing implausible WTP estimates. Further, SAI inclusion did not produce much variation in our WTP estimates.  相似文献   
10.
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