首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Increased fertilizer use will likely be crucial for raising and sustaining farm productivity in Africa, but adoption may be limited by ineffectiveness under certain conditions. This article quantifies the impacts of soil characteristics on maize response to fertilizer in Zambia using a nationally representative sample of 1453 fields, combining economic, farm management and soil analysis data. Depending on soil regimes, average maize yield response estimates range from insignificant (0) to 7 maize kg per fertilizer kg. For the majority of farmers, the estimated average value cost ratio is between 1 and 2, meaning fertilizer use would be fiscally rational, barring uncertainty and transfer costs. Since transfer costs exist and outcomes are uncertain, however, many farmers may sensibly pause before deciding whether to adopt fertilizer. This suggests shifting the emphasis of chronically low fertilizer use in Africa away from explanations of “market failure” toward greater emphasis on improving fertilizer efficacy.  相似文献   

2.
Farm production diversity has the potential to influence the diversity of household diets, an important nutrition outcome associated with the nutrient adequacy of diets and the nutritional status of individuals. Yet, little empirical research has assessed the relationship between farm diversity and diet diversity or the plausible causal mechanisms that may operate between these two constructs. This research examines cross-sectional data from the Malawi Third Integrated Household Survey (IHS3), a nationally representative sample of farming households in Malawi, implemented from March 2010–March 2011 as part of the World Bank Living Standards Measurement Study – Integrated Surveys on Agriculture (LSMS-ISA). These data were used to determine the relationship between farm production diversity and household dietary diversity, and to identify determinants of this relationship. Two indicators of dietary diversity, a modified Household Dietary Diversity Score (HDDS), and the Food Consumption Score (FCS), were calculated along with three indicators of farm production diversity including the Simpson’s Index, a metric accounting for both species richness and evenness. In multiple regression analyses, adjusting standard errors for the complex survey design of the IHS3 and controlling for the effects of several covariates on household dietary diversity, farm production diversity was consistently positively associated with dietary diversity (P < 0.0001). The association of increased farm diversity as measured by a combined crop and livestock measure on dietary diversity was significantly greater in woman-headed households compared to those headed by men (HDDS: P = 0.008; FCS: P = 0.076). The positive association of farm diversity with dietary diversity was also greater in wealthier households (P < 0.05). Consumption of legumes, vegetables and fruits was especially strongly associated with greater farm diversity. More diverse production systems may contribute to more diverse household diets. However, this relationship is complex; it may be influenced by gender, wealth, control of household decisions, the relative market-orientation of a household’s agricultural production, and the specific nature of farm diversity.  相似文献   

3.
It is widely perceived that African farmers are under-utilizing inorganic fertilizer. However, very little long-term evidence from farmers’ fields, accounting for variations in agro-ecological conditions, has been assembled to back this claim or determine the conditions under which it is true. Using five waves of nationwide household survey data from Kenya covering 13 years, we estimate the relative and absolute profitability of nitrogen application rates on maize fields and compare these profitability conditions to observed nitrogen use patterns over time. In general, we find that farmers are consistently and steadily increasing towards risk-adjusted economically optimal rates of fertilizer application over time and that, in the most agriculturally productive areas, farmers’ application rates on maize sometimes exceed rates that maximize profitability. Fertilizer use rates may nevertheless be profitably raised in these areas, but doing so will require the adoption of complementary inputs and management practices that raise maize response rates to fertilizer application. This motivates a more holistic approach to input intensification strategies in the region.  相似文献   

4.
We estimate a model of drug demand and supply that incorporates insurance, advertising, and competition between branded and generic drugs within and across therapeutic classes. We use data on antiulcer drugs from 1991 to 2010. Our simulations show that generics and “me-too” drugs each increased consumer welfare more than $100 million in 2010, holding insurance premiums constant. However, insurance payments in 2010 fell by nearly $1 billion due to generics and rose by over $7 billion due to me-too antiulcer drugs.  相似文献   

5.
Hidden-camera investigations are becoming an increasingly popular means of raising public awareness about farm animal welfare. However, livestock industries claim they are deceptive. One strategy to curtail these investigations has been the introduction of so-called ag-gag legislation, which aims to restrict the flow of information coming out of farm facilities. Psychological research suggests that this approach may be counter-productive as reducing information flow often reduces feelings of trust. We sought to extend these findings by applying them to a real-world, timely example and to determine whether the perceived intention to obstruct access to information erodes feelings of trust. Accordingly, this study tested whether simply being made aware of ag-gag laws might have a negative impact on trust in farmers. Participants (n = 716) were randomly assigned to either receive information about ag-gag laws or to a Control condition. We found that most people were unaware of ag-gag laws and that learning about them lead to a decrease in trust in farmers and an increase in support for animal welfare regulations. Interestingly, we also found evidence that awareness of ag-gag laws negatively impacted perceptions of the current status of farm animal welfare as well as the perception that farmers do a good job of protecting the environment. Through this topical example, this study demonstrates that even the intention to restrict access to information can undermine trust.  相似文献   

6.
Sequestering carbon in soils of agro-ecosystems   总被引:1,自引:0,他引:1  
Soils of the world’s agroecosystems (croplands, grazing lands, rangelands) are depleted of their soil organic carbon (SOC) pool by 25–75% depending on climate, soil type, and historic management. The magnitude of loss may be 10 to 50 tons C/ha. Soils with severe depletion of their SOC pool have low agronomic yield and low use efficiency of added input. Conversion to a restorative land use and adoption of recommended management practices, can enhance the SOC pool, improve soil quality, increase agronomic productivity, advance global food security, enhance soil resilience to adapt to extreme climatic events, and mitigate climate change by off-setting fossil fuel emissions. The technical potential of carbon (C) sequestration in soils of the agroecosystems is 1.2–3.1 billion tons C/yr. Improvement in soil quality, by increase in the SOC pool of 1 ton C/ha/yr in the root zone, can increase annual food production in developing countries by 24–32 million tons of food grains and 6–10 million tons of roots and tubers. The strategy is to create positive soil C and nutrient budgets through adoption of no-till farming with mulch, use of cover crops, integrated nutrient management including biofertilizers, water conservation, and harvesting, and improving soil structure and tilth.  相似文献   

7.
Maize is the most important food staple in Eastern and Southern Africa, with a highly seasonal production but relatively constant consumption over the year. Farmers have to store maize to bridge seasons, for food security and to protect against price fluctuations. However, the traditional storage methods do not protect grain well, resulting in large postharvest losses. Hermetically sealed metal silos kill storage pests by oxygen deprivation without pesticides. Popular in Central America, they are now being promoted in Africa, but their impact here has not yet been studied. This study used propensity score matching to evaluate the impact of metal silos on duration of maize storage, loss abatement, cost of storage, and household food security. Metal silo adopters (N = 116) were matched with non-adopting farmers from a representative sample of 1340 households covering the major maize-growing zones in Kenya. The major effect of the metal silos was an almost complete elimination of losses due to insect pests, saving farmers an average of 150–200 kg of grain, worth KSh9750 (US$130). Metal silo adopters also spent about KSh340 less on storage insecticides. Adopters were able to store their maize for 1.8–2.4 months longer, and to sell their surplus after five months at good prices, instead of having to sell right after the harvest. The period of inadequate food provision among adopters was reduced by more than one month. We conclude that metal silos are effective in reducing grain losses due to maize-storage insects, and that they have a large impact on the welfare and food security of farm households. The initial cost of metal silos is high (KSh20,000/1.8 ton) and therefore policies to increase access to credit, to reduce the cost of sheet metal, and to promote collective action can improve their uptake by smallholder farmers.  相似文献   

8.
This paper investigates the effects of subsidised fertilizer on marketing of maize in Malawi. It uses the nationally representative two-wave Integrated Household Panel Survey (IHPS) data of 2010 and 2013. The results suggest that subsidised fertilizer on average increases farmers’ maize market participation as sellers, total quantity of maize sold, and maize commercialisation. In addition, participation in subsidised fertilizer programme is found to increase the probability of farmers to be net sellers and increases net quantity of maize sold. However, the study finds no evidence of effect on net quantity of maize bought and on household maize self-sufficiency. These results suggest that the farm input subsidy programme has contributed toward an increased level of maize market supply engagement for small farmers and in this sense, the policy has the potential to provide the wider external benefits. Furthermore, the results have implication on the sustainability of the subsidy programme, policy formulation and design of programmes for the agricultural sector and small farmers in developing countries.  相似文献   

9.
Food security in an important public policy issue. In 2015, approximately 1 in 8 U.S. households experienced food insecurity at some point in the year. Low-income families are at higher risk for food insecurity than other families, and these families may also face higher levels of disruption (e.g., moves, loss of income, or individuals entering or leaving the household) than other families. I use data from the Survey of Income and Program Participation to explore the relationship between food insecurity, the household’s history during the previous year, and SNAP participation. The results indicate that a number of aspects of the household’s recent experience including negative income shocks, moves, and both increases and decreases in household size increase the probability of being food insecure while SNAP participation is estimated to reduce the probability of being food insecure.  相似文献   

10.
Although considerable progress has been made in understanding the determinants of risk perception and in identifying the necessary components of effective food risk and benefit communication, this has not been matched with the development of efficient and appropriate communication tools. Little work has been done examining the implications of the explosion of new media and web technologies, which may offer potential for improving food risk and benefit communication. First, this study examines the views of stakeholders (n = 38) and experts (n = 33) in the food domain on the potential use of these emerging media for food risk/benefit communication. Based on in-depth interviews in six European countries (Belgium, Ireland, Italy, Latvia, Spain and The Netherlands), strengths, weaknesses, opportunities and threats (SWOT) of social media in food risk and benefit communication were identified. Second, a Strategic Orientation Round (SOR) was used to evaluate the relative importance of the SWOT components according to stakeholders (n = 10) and experts (n = 13). Results show that both stakeholders and experts confirm a future role of social media in food risk and benefit communication. Strengths as speed, accessibility and interaction make social media an interesting tool in crisis communication or issue awareness raising. Weaknesses as the lack of a filter, low trust, the risk of information overload and a communication preference for traditional media are acknowledged.  相似文献   

11.
This research tests a multistage model of trust in business-to-business (B2B) relationships. The model contains three forms of trust, each with unique drivers and consequences for buyer–supplier relationships. An exploratory qualitative study (N = 38) and four quantitative studies (NTotal = 616) validate the distinct stages (N1 = 140, N2 = 144, N3 = 152) and provide an overall test of the model (N4 = 180), using structural equation modeling techniques. The results support the proposed modeling of the stages and highlight a positive effect of reputation on calculative trust. Conflict resolution, communication, and sympathy positively affect cognitive trust. However, shared values do not significantly drive affective trust. Interdependence also exists among the three trust forms, both directly and indirectly. That is, calculative trust does not affect investments in relationship or confidential communication, but cognitive trust influences these constructs indirectly, through the mediation of affective trust. Affective trust also leads directly to greater investments in relationship and generates additional confidential communication.  相似文献   

12.
In this study we use detailed daily scanner data on household food purchases to examine monthly food expenditure patterns across food retail channels. We compare food expenditure patterns in high and low-income households comparing those where Supplementary Nutrition Assistance (SNAP) is received in the first 10 days of the month versus households which receive SNAP over the first 15 days of the month. We find that food expenditure patterns vary systematically across the month within different retail channels by income and SNAP payment schedules. Low-income households in early SNAP distribution areas decrease their grocery and mass/club/superstore expenditures at the end of the calendar month and supplement this decrease with increased food expenditures in convenience stores and food away from home. Households in staggered SNAP payment areas show far fewer systematic patterns given the more distributed payment system.  相似文献   

13.
This paper determines the cropland use associated with the dietary patterns of 16 European countries and investigates sources of variation in land use between and within these countries. The analysis combines food availability data at the household level with country-specific land use data for food items. The household food availability data is obtained from a standardized and post-harmonized databank, developed in the Data Food Networking Project (DAFNE). The results show large differences between the land use of the 16 European countries, ranging from ±1500 m2 (Ireland) to ±3000 m2 (Malta) to supply an average person’s food demand. Major reasons for this divergence include disparities in total caloric food availability and in national yields. The composition of the diet is only a minor source of variation. Using food consumption data at the household level makes it also possible to look for sources of variation within countries. This paper investigates sources of variation within countries by examining the influence of education of the household head on land use associated with food consumption. The analysis shows that diets of people with only elementary education need on average 20% more land than diets of people with a higher education (2302 m2 and 1948 m2, respectively). The basis of this difference is the higher caloric availability for people with only an elementary education; the influence of differences in the composition of the diet is negligible. Variation in land use between countries is thus caused by the different agricultural productivities and caloric availabilities, and the major source of variation within countries is the caloric availability. The composition of the diet is only a minor source of variation, both between and within countries. The results implicate that highly educated people have a lower demand for land.  相似文献   

14.
Food insecurity is a major challenge facing Peru’s Indigenous Shawi communities, who receive food support through national level programs. There is limited research, however, on how national food and social programming support is perceived, received and used among Indigenous communities. We address this research gap by characterizing the preferred diet and coping mechanisms among Shawi Indigenous households, and investigating community perspectives on the national food program and national social supports. We used a mixed methods approach, including a quantitative survey among eleven Shawi communities in the Peruvian Amazon (n = 177 households), and semi-structured interviews with key informants (n = 24). We found that national food programs in Peru rarely provide foods that are desired and preferred among the Shawi, particularly familiar and locally-sourced protein sources such as bushmeat and fish. Food and social programming requirements do not integrate consideration of the remoteness of many vulnerable households, and are considered culturally or linguistically inaccessible to many families. In some cases, foods supplied by national programs are not consumed as they are perceived as unfamiliar. Key opportunities to improve food and social programing include: monitoring and revising eligibility requirements for remote and highly vulnerable households; increasing provision of locally-preferred protein food and familiar food types; avoiding use of written Spanish as a sole source of information to support programming; extending food provision outside of school months; developing contingency plans during education sector strikes; considering hiring of staff with working knowledge of local languages for community distributions; using visual or oral communication rather than written communication to increase accessibility of programs; increasing knowledge on the use and nutritional value of external food; and considering exemptions to school and health eligibility requirements during the rainy season and during sector strikes. Nationally-developed programming that does not consider Indigenous and cultural contexts risks inefficiency, limited improvement of health outcomes, and the potential to increase inequities in Indigenous health.  相似文献   

15.
Our ability to research dietary changes over time and their effects on health is limited by challenges in accurately measuring food consumption. In countries where dietary surveys are scarce and rarely nationally representative, household budget surveys may serve as a useful alternative for assessing food consumption. The objective of this study was to evaluate how well household acquisition data reflects the actual intake of ultra-processed foods, using data from the 2008 to 2009 Brazilian Household Budget Survey. The food acquisition module was conducted for all households selected for the survey (n = 55,970) and a subsample corresponding to 25% of the households (n = 13,569) was randomly selected for the individual food intake module, which was conducted for all individuals aged 10 years or older (n = 34,003). Ultra-processed foods were defined as formulations made by the food industry mostly or entirely from substances extracted from foods or obtained with the further processing of constituents of foods or through chemical synthesis, with little if any whole food. Examples included candies, cookies, chips, sugar-sweetened beverages, and ready-to-eat dishes. Our results showed an important agreement between the estimates of ultra-processed food consumption obtained from household acquisition data and individual intake inside-the-home data, particularly for the relative (% of total energy) consumption of these foods. Our study thus indicates that household budget surveys are quite promising for tracking population-level changes in the consumption of ultra-processed foods. The trend toward increased consumption of food away from home in other low- and middle-income countries indicates that future household budget surveys should include the collection of these data.  相似文献   

16.
This paper develops a microeconomic model of concentrated animal feeding operations that admits roles for all of animal health inputs, genetic profile choices and the pertaining economic infrastructure. The basic model emphasizes how time on feed, feed density and biosecurity choices interact, as well as how these choices respond to (i) input prices, and (ii) attributes regarding animal productivity parameters that might be influenced by policy choices such as animal welfare strictures and restraints on use of medication. We show that ostensibly substituting inputs in protecting against animal health risks may in fact be complements, and that the model’s production choices come as a complementary package. We then extend the model to endogenize the choice of animal genetics. A finding is that innovations in general infrastructure encourage herd owners to choose more feed efficient, but less hardy, animals. Higher feed conversion efficiency then induces the use of denser feed rations, accelerated finishing and greater levels of biosecurity actions at farm perimeters. Our theory provides a coherent framework for explaining associations among inputs and outcomes that are linked with confined animal agriculture. It also explains how animal protein supply chain technology adoption and performance can differ according to a region’s state of infrastructure, why responses to a change in infrastructure may be large, and why public sector efforts to reduce production risk may beget private sector effort to do so.  相似文献   

17.
Over the last decade, Zambia has witnessed a rapid increase in the number of medium-scale “emergent farms” cultivating 5–20 ha of land. This study analyzes the factors underpinning this growth. We find that the growth of emergent farmers in Zambia is primarily attributable to land acquisition by salaried urbanites and by relatively privileged rural individuals. We found little evidence to support the hypothesis that the rise of emergent farmers primarily represents a process of successful accumulation by farmers who began farming with less than 5 ha of land, a situation faced by more than 95% of farming households. We argue that these outcomes are the result of Zambia’s land administration and agricultural spending policies. Rising concentration of landholdings in Zambia raises serious questions about the potential of current agricultural growth to act as a vehicle for broad based economic growth and poverty reduction.  相似文献   

18.
We take advantage of four different cross-country datasets containing data on 78 countries for the period 1999–2014, in order to assess the relationship of carbonated soft drinks’ sales, as well as their prices, with body mass index (BMI), overweight, obesity and diabetes. Using an ecological study design and multivariate regression longitudinal estimation approaches, we find that carbonated soft drink sales were significantly positively related to BMI, overweight and obesity – but only in the low and lower-middle income countries. This finding was robust to a number of sensitivity and falsification checks. In this sub-sample, an increase in per capita soft drink sales by 1 litre per year was related to an increase of BMI by about 0.009 kg/m2 (p < 0.1).. This is a small effect, implying that halving annual consumption per capita in this group of countries would result in a drop of BMI by only about 0.03 kg/m2. Although soft drink prices were negatively related to weight-related outcomes in the sample of higher middle income and high income countries, this finding was not robust to falsification checks. The results thus suggest that sales restrictions to steer consumers away from soft drinks could indeed have a beneficial health effects in poorer countries, although the effect magnitude appears to be very small. However, given potential limitations of using ecological research design, results from individual level studies would be required to further ascertain the role of soft drink sales and prices in obesity and diabetes.  相似文献   

19.
20.
A proposal to lower the bulk tank Somatic Cell Count (SCC) maximum for United States of America (US) Grade “A” milk producers was not adopted by the National Conference on Interstate Milk Shipments in 2011 or 2013. The proposal would have made the US Grade “A” limit consistent with many other international standards, including that of the European Union (EU). Some US states, however, have proactively adopted their own SCC limit to mirror the EU limit. The purpose of this study was to analyze the impacts on Wisconsin dairy producers if Wisconsin should adopt the current EU limit and compliance criterion. Analyses were done on SCC results for Wisconsin Grade “A” and Grade “B” dairy producers reported each month to the Wisconsin Department of Agriculture, Trade and Consumer Protection (WDATCP) during January 1, 2009–December 31, 2012. Results were evaluated against the current US Grade “A” and EU compliance criteria for SCC and the percentage of (producer × month) combinations in compliance was determined. If the current EU SCC compliance criterion was in place, 86.7–94.3 and 64.3–77.3% of Wisconsin Grade “A” and “Grade “B” (producer × month) combinations, respectively, would have been in compliance for the years 2009–2012. Compliance of Wisconsin Grade “A” and Grade “B” producers with the existing US SCC compliance criterion during the same period was 99.3–99.7% and 87.9–93.9% (producer × month combinations) respectively. An analysis of a subset of Wisconsin Grade “A” producers indicated that smaller-volume producers were less likely than larger-volume producers to meet the EU criterion.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号