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1.
This paper surveys the theoretical literature on the relationship between income distribution and food demand, and identifies main gaps of current food modelling techniques that affect the accuracy of food demand projections. At the heart of the relationship between income distribution and food demand is Engel''s law. Engel''s law establishes that as income increases, households'' demand for food increases less than proportionally. A consequence of this law is that the particular shape of the distribution of income across individuals and countries affects the rate of growth of food demand. Our review of the literature suggests that existing models of food demand fail to incorporate the required Engel flexibility when (i) aggregating different food budget shares among households; and (ii) changing budget shares as income grows. We perform simple simulations to predict growth in food demand under alternative income distribution scenarios taking into account nonlinearity of food demand. Results suggest that (i) distributional effects are to be expected from changes in between-countries inequality, rather than within-country inequality; and (ii) simulations of an optimistic and a pessimistic scenario of income inequality suggest that world food demand in 2050 would be 2.7 per cent higher and 5.4 per cent lower than distributional-neutral growth, respectively.  相似文献   

2.
For many of the world’s poor, aquatic products are critical for food security and health. Because the global population is increasing as wild aquatic stocks are declining, aquaculture is an increasingly important source of aquatic products. We undertook a scoping review of the English-language peer-reviewed literature to evaluate how the research community has examined the impacts of aquaculture on four key determinants of human health: poverty, food security, food production sustainability, and gender equality. The review returned 156 primary research articles. Most research (75%) was focused in Asia, with limited research from Africa (10%) and South America (2%). Most research (80%) focused on freshwater finfish and shrimp production. We used qualitative content analysis of records which revealed 11 themes: famer income; the common environment; shared resources; integrated farming/ polyculture; employment; extensive vs. intensive production; local vs. distant ownership; food security; income equity; gender equality; and input costs. We used quantitative content analysis of records and full-text publications about freshwater finfish and shrimp aquaculture to record the frequency with which themes were represented and the positive or negative impacts of aquaculture associated with each theme. Scatter plots showed that no theme was identified in more than half of all articles and publications for both production types. Farmer income was a theme that was identified commonly and was positively impacted by both shrimp and fresh water finfish aquaculture. Polyculture, employment, and local ownership were identified less often as themes, but were also associated with positive impacts. The common environment and shared resources were more common themes in shrimp aquaculture than freshwater finfish aquaculture research, while polyculture and local ownership were more common themes in freshwater finfish aquaculture than shrimp aquaculture. Gender equality, employment, and food security were themes found in a lower percentage of records than full-text publications for both production types.  相似文献   

3.

Objective

Previous studies have shown that estimations of the calorie content of an unhealthy main meal food tend to be lower when the food is shown alongside a healthy item (e.g. fruit or vegetables) than when shown alone. This effect has been called the negative calorie illusion and has been attributed to averaging the unhealthy (vice) and healthy (virtue) foods leading to increased perceived healthiness and reduced calorie estimates. The current study aimed to replicate and extend these findings to test the hypothesized mediating effect of ratings of healthiness of foods on calorie estimates.

Methods

In three online studies, participants were invited to make calorie estimates of combinations of foods. Healthiness ratings of the food were also assessed.

Results

The first two studies failed to replicate the negative calorie illusion. In a final study, the use of a reference food, closely following a procedure from a previously published study, did elicit a negative calorie illusion. No evidence was found for a mediating role of healthiness estimates.

Conclusion

The negative calorie illusion appears to be a function of the contrast between a food being judged and a reference, supporting the hypothesis that the negative calorie illusion arises from the use of a reference-dependent anchoring and adjustment heuristic and not from an ‘averaging’ effect, as initially proposed. This finding is consistent with existing data on sequential calorie estimates, and highlights a significant impact of the order in which foods are viewed on how foods are evaluated.  相似文献   

4.
In order to test the effect of calorie information on fast food choices, we conducted a questionnaire employing two types of stated preferences methods (the best-worst-scaling and intentional questions) and a follow-up randomized field experiment in a sample of 119 participants. This combined approach allowed us to test the internal validity of preferences for fast food meals across elicitation scenarios. The results showed that calorie information reduces the probability of selecting high calorie meals only in the questionnaire, while it did not have any significant impact on actual purchasing behavior in the field experiment. Thus, the findings show that there is a clear difference between the role of calorie information on immediate stated preference choices, and the relatively low level of responsiveness in real choices in a restaurant. We believe that the current results are quite suggestive, indicating the limits of predicting actual fast food behavior, and may open the way to using data sources that combine stated methods with field experiments.  相似文献   

5.
Fast‐food restaurants provide a growing share of daily food intake, but little information is available in the public health literature about customer purchases. In order to establish baseline data on mean calorie intake, this study was completed in the Spring of 2007, before calorie labeling regulations went into effect in New York City. Receipts were collected from lunchtime customers, at randomly selected New York City fast‐food chains. A supplementary survey was also administered to clarify receipt items. Calorie information was obtained through company websites and ascribed to purchases. Lunchtime purchases for 7,750 customers averaged 827 calories and were lowest for sandwich chains (734 calories); and highest for chicken chains (931 calories). Overall, one‐third of purchases were over 1,000 calories, predominantly from hamburger chains (39%) and chicken chains (48%); sandwich chains were the lowest, with only 20% of purchases over 1,000 calories. “Combination meals” at hamburger chains accounted for 31% of all purchases and averaged over 1,200 calories; side orders accounted for almost one‐third of these calories. Lunch meals at these fast‐food chains are high in calorie content. Although calorie posting may help to raise awareness of the high calories in fast‐food offerings, reducing portion sizes and changing popular combination meals to include lower calorie options could significantly reduce the average calorie content of purchases.  相似文献   

6.
Most traits associated with drought tolerance have a dual effect, positive in very severe scenarios and negative in milder scenarios, or the opposite trend. Their effects also depend on other climatic conditions such as evaporative demand or light, and on management practices. This is the case for processes associated with cell protection and with avoidance, but also for the maintenance of growth or photosynthesis, high water use efficiency, large root systems or reduced abortion rate under water deficit. Therefore, spectacular results obtained in one drought scenario may have a limited interest for improving food security in other geographical areas with water scarcity. The most relevant questions on drought tolerance are probably, 'Does a given allele confer a positive effect on yield in an appreciable proportion of years/scenarios in a given area or target population of environment (TPE)?'; 'In a given site or TPE, what is the trade-off between risk avoidance and maintained performance?'; and 'Will a given allele or trait have an increasingly positive effect with climate change?' Considerable progress has already occurred in drought tolerance. Nevertheless, explicitly associating traits for tolerance to drought scenarios may have profound consequences on the genetic strategies, with a necessary involvement of modelling.  相似文献   

7.
Food preferences (FP) predict food intake in childhood; however, the predictive power of FP may decline among girls as weight concerns (WC) and dietary restraint (DR) increase during preadolescence. To examine longitudinal change in the preference‐intake (P‐I) relation and assess whether this relation weakens among non‐Hispanic white girls (n = 197) with a history of WC and DR from age 5 to 11. Girls' preferences for and intake (kcal) of 10 palatable snack foods were assessed biennially. Height, weight, percent body fat (%BF), WC, and DR were measured. Individual correlation coefficients were calculated per girl to capture within‐person P‐I correlations at each time of measurement. Overall, FP predicted girls' snack food calorie intakes between 5 and 11 years, but latent profile analysis (LPA) revealed three distinct patterns of change in P‐I correlations over time: “strong/stable” P‐I correlations were relatively high and became stronger with age; “increasing/later null” P‐I correlations were initially weak and became stronger between 5 and 9 years, but dropped to near 0 at 11 years; “initially weak/later strong” P‐I correlations were initially null and increased with age. Mixed models revealed that the “increasing/later null” group had greater increases in %BF, and higher WC, DR, and BMI percentiles from 5 to 11 years, compared to the other groups. In summary, FP predicted snack food calorie intake among most girls during childhood, but waned as a predictor of calorie intake at age 11 for a subset of girls with increasing %BF, and higher WC, DR, and BMIs.  相似文献   

8.

Purpose

Food consumption is one of the main drivers of environmental impacts. To develop meaningful strategies for the reduction of impacts, food consumption patterns need to be understood on the household level, as purchasing decisions are taken on this level. The goals of this study were to develop a model that estimates food demand and environmental impact as a function of household characteristics, to assess variability between households, and to provide a basis for the development of consumer-targeted political interventions. We titled the study “FoodPrints of households,” as we assessed food consumption in terms of carbon footprint (in analogy to (Stoessel et al. Environ Sci Technol 46(6):3253–3262 2012)).

Methods

We used data from the Swiss household budget survey and applied multiple linear regressions based on generalized linear models to quantify food and beverage demand of individual households. Seven household characteristics, such as size, income, and educational level, served as input variables for the regressions. In a case study, food and beverage demand of 3238 individual households of a Swiss municipality was environmentally assessed with life cycle assessment, and scenarios for different reduction strategies were evaluated.

Results and discussion

We found that the carbon footprints of in-home food consumption per household member and year vary from 0.08 t CO2 eq. to 5 t CO2 eq. with a median value of 1 t CO2 eq. This variability is significantly smaller than the carbon footprint variability for the consumption areas of housing and mobility, where 25 % of the people are responsible for 50 % of the environmental impacts. Differences between high- and low-impact households can be primarily explained by differences in meat and dairy consumption.

Conclusions

This paper presents a model for quantifying food demand and impacts on a household level in Switzerland and represents a basis for developing targeted political measures to mitigate food consumption impacts. Household budget data is also available for many other countries, and the methods presented in this paper could therefore also be applied to other geographical regions.
  相似文献   

9.
城市磷代谢不但关系到居民食品安全,还影响到城市生态系统的环境质量.快速的城市化进程及由此带来的居民生活水平的提高,会改变食物消费的数量、质量和结构,从而对城市磷代谢产生重要影响.分析了1988-2010年厦门市经食物消费进入城市系统的磷素变化动态,在此基础上对人均食物磷消费量与相关社会经济因子进行了Spearman相关分析,并计算了居民食物磷素消费的环境负荷.研究结果表明:(1)随着厦门城市化进程的推进,食物磷素消费总量波动上升;人均食物磷素消费量呈M型变化,两个峰值分别出现在1998年和2003年;高磷含量食物如奶制品、水产品,在人均食物磷素消费量中所占比例剧增,分别由0.3%和6.8%上升至14.9%和15.5%.(2)人均粮食磷素消费量与恩格尔系数、平均家庭人口数呈高度正相关,与人均可支配收入、食物价格指数以及具有大学学历以上人口比重呈高度负相关;而植物油、瓜果、畜禽肉、蛋类、奶类和水产品磷素消费量则与粮食所呈现的相关性相反.(3)随着食物磷素消费总量的增加,磷素的环境负荷总量也呈剧增趋势,尤其进入土壤的磷素量剧烈上升,所占比例由59.7%增至85.1%,这可能与禁磷措施的实行、污水处理率的提高、处理工艺的改进等有关.  相似文献   

10.
Perennial biomass crops (PBC) are considered a crucial feedstock for sustainable biomass supply to the bioeconomy that compete less with food production compared to traditional crops. However, large‐scale development of PBC as a means to reach greenhouse gas (GHG) mitigation targets would require not only the production on land previously not used for agriculture, but also the use of land that is currently used for agricultural production. This study aims to evaluate agricultural market impacts with biomass demand for food, feed, and PBC in four bioeconomy scenarios (“Business as usual,” “Improved relevance of bioeconomy,” “Extensive transformation to a bioeconomy,” “Extensive transformation to a bioeconomy with diet change”) to achieve a 75% GHG reduction target in the emission trading sector of the EU until 2050. We simulated bioeconomy scenarios in the energy system model TIMES‐PanEU and the agricultural sector model ESIM and conducted a sensitivity analysis considering crop yields, PBC yields, and land use options of PBC. Our results show that all bioeconomy scenarios except the one with diet change lead to increasing food prices (the average food price index increases by about 11% in the EU and 2.5%–3.0% in world markets). A combination of the transformation to a bioeconomy combined with diet change toward less animal protein in the EU is the only scenario that results in only moderately increasing food prices within the EU (+3.0%) and even falling global food prices (–6.4%). In addition, crop yield improvement and cultivation of PBC on marginal land help to reduce increases in food prices, but higher land prices are inevitable because those measures have only small effects on sparing agricultural land for PBC. For a transition to a bioeconomy that acknowledges climate mitigation targets, counter‐measures for those substantial direct and indirect impacts on agricultural markets should be taken into account.  相似文献   

11.
Responsiveness to food cues, especially those associated with high‐calorie nutrients may be a factor underlying obesity. An increased motivational potency of foods appears to be mediated in part by the hippocampus. To clarify this, we investigated by means of 3‐T magnetic resonance imaging (MRI) the activation of the hippocampus and associated brain structures in response to pictures of high‐calorie and low‐calorie foods in 12 obese and 12 normal‐weight adolescents. To investigate the relationship between neuronal activation patterns (e.g., hippocampus) to the caloric content of food images and plasma insulin levels, we performed a multiple regression analysis. Interestingly, a significant positive correlation between fasting plasma levels of insulin, waist circumference, and right hippocampal activation was seen after stimulation with high‐caloric food images. BMI values did not correlate significantly with the hippocampal activation. On the other hand, we found a significant negative correlation in response to high‐caloric food images and the plasma levels of insulin in the medial right gyrus frontalis superior and in the left thalamus. In summary, our data show that insulin is importantly involved in the central regulation of food intake. The significant positive relationship between hippocampal activation after stimulation with high‐caloric food images, plasma insulin levels, and waist circumference suggests a permissive role of insulin signaling pathways in the hippocampal control of eating behavior. Interestingly, only the waist circumference, as a main indicator of abdominal obesity, correlated significantly with the hippocampal activation patterns, and not the BMI.  相似文献   

12.
This is part of a project on the disadvantaged, marginalized, vulnerable/weaker section of the population and their survival strategy. The paper presents the results of a survey carried out during 2006-07 with the objective of throwing light on the life and living conditions of an economically weaker community such as 'fishing community' residing in the coastal area of Bay of Bengal in West Bengal and Orissa, India, in the context of global scenario. Various scientists have conducted quite a large number of studies to ascertain the income and nutritional status of people in rural India. Very few attempts, however, have been made to investigate in detail regarding the living standards of some specific communities, which are very often referred to, as the 'weaker section' of the people. The people belonging to fishing community are, by and large, not only economically weak in terms of earning and availability of work, the majority of them are not able to procure the minimum nourishment. The present study shows that some notable elements of living conditions such as food, shelter, health etc. matters much more than the conventional income or calorie deficiency. Commonly, the social scientists equate poverty with income or calorie deficiency which may not be the case as is evident from this study. We have hinted some measures to be undertaken to ameliorate the sufferings of the fishing community.  相似文献   

13.
A comprehensive assessment of the impacts of climate change on agro-ecosystems over this century is developed, up to 2080 and at a global level, albeit with significant regional detail. To this end an integrated ecological-economic modelling framework is employed, encompassing climate scenarios, agro-ecological zoning information, socio-economic drivers, as well as world food trade dynamics. Specifically, global simulations are performed using the FAO/IIASA agro-ecological zone model, in conjunction with IIASAs global food system model, using climate variables from five different general circulation models, under four different socio-economic scenarios from the intergovernmental panel on climate change. First, impacts of different scenarios of climate change on bio-physical soil and crop growth determinants of yield are evaluated on a 5' X 5' latitude/longitude global grid; second, the extent of potential agricultural land and related potential crop production is computed. The detailed bio-physical results are then fed into an economic analysis, to assess how climate impacts may interact with alternative development pathways, and key trends expected over this century for food demand and production, and trade, as well as key composite indices such as risk of hunger and malnutrition, are computed. This modelling approach connects the relevant bio-physical and socio-economic variables within a unified and coherent framework to produce a global assessment of food production and security under climate change. The results from the study suggest that critical impact asymmetries due to both climate and socio-economic structures may deepen current production and consumption gaps between developed and developing world; it is suggested that adaptation of agricultural techniques will be central to limit potential damages under climate change.  相似文献   

14.

Background

As the global human population grows and its consumption patterns change, additional land will be needed for living space and agricultural production. A critical question facing global society is how to meet growing human demands for living space, food, fuel, and other materials while sustaining ecosystem services and biodiversity [1].

Methodology/Principal Findings

We spatially allocate two scenarios of 2000 to 2015 global areal change in urban land and cropland at the grid cell-level and measure the impact of this change on the provision of ecosystem services and biodiversity. The models and techniques used to spatially allocate land-use/land-cover (LULC) change and evaluate its impact on ecosystems are relatively simple and transparent [2]. The difference in the magnitude and pattern of cropland expansion across the two scenarios engenders different tradeoffs among crop production, provision of species habitat, and other important ecosystem services such as biomass carbon storage. For example, in one scenario, 5.2 grams of carbon stored in biomass is released for every additional calorie of crop produced across the globe; under the other scenario this tradeoff rate is 13.7. By comparing scenarios and their impacts we can begin to identify the global pattern of cropland and irrigation development that is significant enough to meet future food needs but has less of an impact on ecosystem service and habitat provision.

Conclusions/Significance

Urban area and croplands will expand in the future to meet human needs for living space, livelihoods, and food. In order to jointly provide desired levels of urban land, food production, and ecosystem service and species habitat provision the global society will have to become much more strategic in its allocation of intensively managed land uses. Here we illustrate a method for quickly and transparently evaluating the performance of potential global futures.  相似文献   

15.
Livestock production is an important contributor to sustainable food security for many nations, particularly in low‐income areas and marginal habitats that are unsuitable for crop production. Animal products account for approximately one‐third of global human protein consumption. Here, a range of indicators, derived from FAOSTAT and World Bank statistics, are used to model the relative vulnerability of nations at the global scale to predicted climate and population changes, which are likely to impact on their use of grazing livestock for food. Vulnerability analysis has been widely used in global change science to predict impacts on food security and famine. It is a tool that is useful to inform policy decision making and direct the targeting of interventions. The model developed shows that nations within sub‐Saharan Africa, particularly in the Sahel region, and some Asian nations are likely to be the most vulnerable. Livestock‐based food security is already compromised in many areas on these continents and suffers constraints from current climate in addition to the lack of economic and technical support allowing mitigation of predicted climate change impacts. Governance is shown to be a highly influential factor and, paradoxically, it is suggested that current self‐sufficiency may increase future potential vulnerability because trade networks are poorly developed. This may be relieved through freer trade of food products, which is also associated with improved governance. Policy decisions, support and interventions will need to be targeted at the most vulnerable nations, but given the strong influence of governance, to be effective, any implementation will require considerable care in the management of underlying structural reform.  相似文献   

16.
Peru is the top exporter of fishmeal and fish oil (FMFO) worldwide and is responsible for half and a third of global production, respectively. Landings of “anchoveta” (Engraulis ringens) are used nearly exclusively for FMFO production, despite a proactive national food policy aimed at favoring the direct human consumption of this inexpensive species. It may be surprising that in a country where malnutrition and caloric deficit constitute major issues, a low-priced and highly nutritious fish such as anchovy does not have stronger domestic demand as a food fish. Here, we review and assess eight potential politico-socio-economic processes that can explain this situation. The main explanation are dietary habits, the preference for broiler and the higher profit from anchovy sold as feed fish compared to its use as a food fish due to historically high FMFO prices, boosted by an increasing demand for aquaculture in a context of finite forage and trash fish resources. In addition, the recent introduction of an individual quota system has shifted bargaining power from processors to fishers, thereby increasing competition for the raw material. This competition results in an increase in anchovy prices offered by the feed fish industry due to its onshore processing overcapacity, which is detrimental to the food fish industry. In the end, although the dominant use of anchovy for fish feed is largely explained by integrating these market mechanisms and other minor ones, this use raises other issues, such as rent redistribution through public policies, employment, equitability and utility (low social costs), and resource management (threats to ecosystems or global change). Different policy scenarios are proposed in relation to these issues.  相似文献   

17.
A simple, globally aggregated, stochastic-simulation model was constructed to examine the effects of rapid climatic change on agriculture and the human population. The model calculates population size and the production, consumption and storage of grain under different climate scenarios over a 20-year projection time. In most scenarios, either an optimistic baseline annual increase of agricultural output of 1.7% or a more pessimistic appraisal of 0.9% was used. The rate of natural increase of the human population exclusive of excess hunger-related deaths was set as 1.7% per year and climatic changes with both negative and positive impacts on agriculture were assessed. Analysis of the model suggests that the number of hunger-related deaths could double (with reference to an estimated 200 million deaths in the past two decades) if grain production keeps pace with population growth but climatic conditions are unfavourable. If the rate of increase in grain production is about half that of population growth, the number of hunger-related deaths could increase about fivefold (over past levels); the impact of climatic change is relatively small under this imbalance. Even favourable climatic changes that enhance agricultural production may not prevent a fourfold increase in deaths (over past levels) under scenarios where population growth outpaces production by about 0.8% per annum. These results may foreshadow a fundamental change where, for the first time, absolute global food deficits compound inequities in food production and distribution in causing famine. The model also highlights the effectiveness of reducing population growth rates as a strategy for minimizing the impact of global climate change and maintaining food supplies for everyone.  相似文献   

18.
There is disagreement on whether the supply of lithium is adequate to support a future global fleet of electric vehicles. We report a comprehensive analysis of the global lithium resources and compare it to an assessment of global lithium demand from 2010 to 2100 that assumes rapid and widespread adoption of electric vehicles. Recent estimates of global lithium resources have reached very different conclusions. We compiled data on 103 deposits containing lithium, with an emphasis on the 32 deposits that have a lithium resource of more than 100,000 tonnes each. For each deposit, data were compiled on its location, geologic type, dimensions, and content of lithium as well as current status of production where appropriate. Lithium demand was estimated under the assumption of two different growth scenarios for electric vehicles and other current battery and nonbattery applications. The global lithium resource is estimated to be about 39 Mt (million tonnes), whereas the highest demand scenario does not exceed 20 Mt for the period 2010 to 2100. We conclude that even with a rapid and widespread adoption of electric vehicles powered by lithium‐ion batteries, lithium resources are sufficient to support demand until at least the end of this century.  相似文献   

19.
Increased livestock production in developing countries is seen as one way to improve world food supply. However, the impact of increased livestock production on household health and nutrition is unknown. This paper examines linkages between commercialization of livestock production and household nutrition. Linkages include income, resource allocation, food consumption, and human disease risk. Data from Uasin Gishu district, Kenya, show higher consumption of animal products for large commercialized farms, along with greater control of milk sales by men. Effects of livestock development may thus differ by gender, and may include both positive and negative impacts.  相似文献   

20.
To analyse trends in greenhouse gas (GHG) emissions from production and consumption of animal products in Sweden, life cycle emissions were calculated for the average production of pork, chicken meat, beef, dairy and eggs in 1990 and 2005. The calculated average emissions were used together with food consumption statistics and literature data on imported products to estimate trends in per capita emissions from animal food consumption. Total life cycle emissions from the Swedish livestock production were around 8.5 Mt carbon dioxide equivalents (CO2e) in 1990 and emissions decreased to 7.3 Mt CO2e in 2005 (14% reduction). Around two-thirds of the emission cut was explained by more efficient production (less GHG emission per product unit) and one-third was due to a reduced animal production. The average GHG emissions per product unit until the farm-gate were reduced by 20% for dairy, 15% for pork and 23% for chicken meat, unchanged for eggs and increased by 10% for beef. A larger share of the average beef was produced from suckler cows in cow–calf systems in 2005 due to the decreasing dairy cow herd, which explains the increased emissions for the average beef in 2005. The overall emission cuts from the livestock sector were a result of several measures taken in farm production, for example increased milk yield per cow, lowered use of synthetic nitrogen fertilisers in grasslands, reduced losses of ammonia from manure and a switch to biofuels for heating in chicken houses. In contrast to production, total GHG emissions from the Swedish consumption of animal products increased by around 22% between 1990 and 2005. This was explained by strong growth in meat consumption based mainly on imports, where growth in beef consumption especially was responsible for most emission increase over the 15-year period. Swedish GHG emissions caused by consumption of animal products reached around 1.1 t CO2e per capita in 2005. The emission cuts necessary for meeting a global temperature-increase target of 2° might imply a severe constraint on the long-term global consumption of animal food. Due to the relatively limited potential for reducing food-related emissions by higher productivity and technological means, structural changes in food consumption towards less emission-intensive food might be required for meeting the 2° target.  相似文献   

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