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[en] The coffee market is distinguished for being volatile and uncertain in terms of domestic and international prices. Arabica and Robusta coffee are produced in 23 provinces of Ecuador. A decade-long decline of coffee production prompted the Ecuadorian government to launch a public program for replanting coffee trees towards the end of 2011. A grower’s decision to enter, remain in or exit the coffee sector is based on fluctuating profits from each year’s harvest sale. We analyzed the hypothesis whereby the coffee grower’s decision to leave the sector is explained by volatile and uncertain prices. This paper aimed to evaluate the coffee sector with an application of Real Option Analysis for the period 2002-2012. We also defined entry (H) and exit (L) prices for Arabica and Robusta coffee for the analyzed period. Our findings revealed high H and L prices encourage growers to leave the sector for the most part of the analyzed period. High H and L prices resulted from high variable cost due to increasing wages for farm workers. The Ecuadorian government is developing a policy to help growers make production more efficient, encouraging them to remain in the sector in the long run.
[en] Ethanol production in Brazil has grown by 219% between 2001 and 2012, increasing the use of land and water resources. In the semi-arid north-eastern Brazil, irrigation is the main way for improving sugarcane production. This study aimed at quantifying water consumed in ethanol production from sugarcane in this region using the water footprint (WF) indicator and complementing it with an evaluation of the water apparent productivity (WAP). This way we were able to provide a measure of the crop´s physical and economic water productivity using, respectively, the WF and WAP concepts. We studied sugarcane cultivation under nine different water regimes, including rainfed and full irrigation. Data from a mill of the state of Alagoas for three production seasons were used. Irrigation influenced sugarcane yield increasing total profit per hectare and economic water productivity. Full irrigation showed the lowest WF, 1229 litres of water per litre of ethanol (L/L), whereas rainfed production showed the highest WF, 1646 L/L. However, the lower WF in full irrigation as compared to the rest of the water regimes implied the use of higher volumes of blue water per cultivated hectare. Lower water regimes yielded the lowest economic productivity, 0.72 US$/m3 for rainfed production as compared to 1.11 US$/m3 for full irrigation. Since economic revenues are increased with higher water regimes, there are incentives for the development of these higher water regimes. This will lead to higher general crop water and economic productivity at field level, as green water is replaced by blue water consumption. (Author)
[en] The rise of prices of agricultural commodities in global markets during 2007-2012 was followed by increased consumer food prices around the world. More expensive food may have an impact on consumer food access and thus on their welfare, not only in developing countries but also amongst the most vulnerable in developed countries. Using a longitudinal database from the Statistics on Income and Living Conditions and population-averaged models, we tested whether increasing food prices had an impact on household food deprivation in 26 European Union (EU) member states. Results revealed a significant relationship between food deprivation and the consumer food price index and disposable income. Households in the lowest income quintile in the member states recently acceded to the EU were the most vulnerable to food deprivation. Results also showed that low-income households in densely populated areas were more vulnerable to food deprivation. This should be taken into account when evaluating food assistance programmes that focus on the segments of the population most at risk of food deprivation.
[en] In the western part of Sierra de los Filabres (in the Nevado-Filábride Complex, within the Betic Internal Zone) several tectonic units have been described, in varying numbers depending on the author describing them. However, new cartographical data show that the limits of these units pass through the lithological formations without displacing them. Moreover, the rocks belonging to some units that are supposedly situated in a lower tectonic position really belong to higher formations. From bottom to top, these lithological formations are the following: (1) dark schists and quartzites; (2) quartzites, sandstones, sands, lutites, schists, and mica schists; (3) schists; (4) marbles, schists, and mica schists. High-angle reverse faults are associated with the great E-W anticline of Sierra de los Filabres. The existence of sands and apparent lutites visibly interlayered between rocks, such as schists and mica schists with garnets, poses a metamorphic problem that has not as yet been addressed. (Author)
[en] Hydrological droughts are a major risk for irrigated agriculture in many regions of the world. The aim of this article is to propose an insurance tool to help irrigators manage the risk of water scarcity in the framework of the Spanish Crop Insurance System (SCIS). Only the United States Insurance System provides this type of coverage, but has very restrictive conditions. To determine the type of insurance scheme that better fits with the SCIS and to the Spanish irrigated agriculture, an expert panel was held with the participation of all stakeholders involved in crop insurance. Following the expert panel conclusions, an hydrological drought index insurance (HDII) addressed to irrigation districts (ID) is proposed. It would compensate water deficits suffered in the whole ID. We detail the conditions that the ID should fulfill to be eligible for HDII. HDII is applied to the Bardenas Irrigation District V (ID-V) in Spain, and the hedging effectiveness of the instrument is analyzed comparing ID-V’s gross margins with and without the insurance contract. Results suggest that the proposed insurance scheme could provide an effective means of reducing farmers’ vulnerability to water shortages and there is no major impediment for it to be included as a new line in the SCIS. This type of insurance can be generalized to any ID fulfilling the conditions mentioned in this paper. (Author)
[en] Hydrological drought is expected to have an increasing impact on both crop and fruit yields in arid and semi-arid regions. Some existing crop insurance schemes provide coverage against water deficits in rain-fed agriculture. The Prevented Planting Program in the USA covers against drought for irrigated agriculture. However, drought insurance for irrigated agriculture is still a challenge for companies and institutions because of the complexity of the design and implementation of this type of insurance. Few studies have attempted to evaluate the risk of loss due to irrigation water scarcity using both stand-alone production functions and crop simulation models. This paper’s contributions are that it evaluates the suitability of AquaCrop for calculating drought insurance premiums for irrigated agriculture and that it discusses contract conditions and insurance design for hydrological drought risk coverage as part of a traditional insurance product, with on-field loss assessment in combination with a trigger index. This method was applied to an irrigation district in southern Spain. Our insurance premium calculation showed that it is feasible to apply this method provided that its data requirements are met, such as a large enough set of reliable small-scale yield and irrigation time series data, especially soil data, to calibrate AquaCrop. The choice of a trigger index should not be underestimated because it proved to have a decisive influence on insurance premiums and indemnities. Our discussion of the contract conditions shows that hydrological drought insurance must comply with a series of constraints in order to avoid moral hazard and basis risk. (Author)
[en] Numerous studies have analyzed the factors that determine food security and explored the problem from regional or national points of view. However, there has been less research targeting an understanding of the food security problem at the household level in specific rural locations like indigenous communities. Indigenous groups are recognized as priority groups in Mexico, because they live in a situation of poverty. For this reason, the objective of this research was to investigate the determinants of food insecurity among the indigenous communities of the Sierra Tarahumara in Mexico. We used the Latin American and Caribbean Household Food Security Measurement Scale (ELCSA). This scale is useful for measuring food insecurity levels in households. A questionnaire was administered to 123 households. We employed the method based on Cronbach's alpha to measure internal consistency, which was 0.96. In addition, we estimated the main determinants of household food insecurity using both ordered logit model and binomial logit model. We found that approximately 59.35% of households were living in a situation of severe food insecurity. The two predictive models applied suggest that: i) income is the most important determinant of access to food; ii) increased maize production improves food security; iii) farmers consume their seed stocks in times of food scarcity, and iv) households are food insecure when the householders are in casual employment. Akaike's information criterion and the Bayesian information criterion suggest that the goodness of fit to the data was better for the ordered logit model.
[en] Analysis of yield gaps were conducted in the context of crop insurance and used to build an indicator of asymmetric information. The possible influence of asymmetric information in the decision of Spanish wheat producers to contract insurance was additionally evaluated. The analysis includes simulated yield using a validated crop model, CERES-Wheat previously selected among others, whose suitability to estimate actual risk when no historical data are available was assessed. Results suggest that the accuracy in setting the insured yield is decisive in farmers’ willingness to contract crop insurance under the wider coverage. Historical insurance data, when available, provide a more robust technical basis to evaluate and calibrate insurance parameters than simulated data, using crop models. Nevertheless, the use of crop models might be useful in designing new insurance packages when no historical data is available or to evaluate scenarios of expected changes. In that case, it is suggested that yield gaps be estimated and considered when using simulated attainable yields.
[en] This paper is directed at evaluating the theoretical potential of an intensive solar intervention in the historical centre of the city of Jaen (Spain). Using the outputs of a solar intervention proposal comprising biomass, photovoltaics and solar thermal domestic hot water (DHW) over a 50-building sample (in which those suitable for solar measures have been selected by evaluating each one over a collection of parameters), energy savings, environmental benefits and economic aspects of the envisaged actions are extrapolated over the entire historical centre. A saving of about 70% of conventional source energy annual consumption and a decrease of some 70% and 73% of CO2 and SOx annual releases, respectively, could be reached with respect to the present situation. Besides, an amount of conventionally generated electricity equivalent to the yearly photovoltaic-generated electricity would require 131 500 m3 of water a year, which is a rather significant feature for a dry climate like that of the city. The unitary cost of energy in the new scenario would be 60.7 pta kWh-1 for photovoltaics, 329.9 pta m-3 for DHW using solar thermal installations and 4.6 Pta kWh-1 for biomass heating (1 USdollars = 132.7 pta; 1 ECU 160.9 pta). (author)
[en] Recently, fullerene structures with symmetrically arranged pairs of pentagonal/heptagonal defects have been proposed to explain the round shape of giant multilayer fullerene cages. Using a Tersoff-Brenner potential the shapes of these defective fullerenes are calculated. It has been found that they present a rounder shape than structures without defects. It has been calculated the electronic structure of these fullerenes with defects. Electronic structures are closed and gaps between bonding and antibonding orbitals are higher in almost all cases than for fullerenes with no defects
[ru]Недавно предложены структуры фуллеренов с симметрично размещенными парами пятиугольных/семиугольных дефектов, которые позволяют объяснять круглую форму гигантских многослойных решеток фуллеренов. Формы этих дефектных фуллеренов рассчитаны с применением потенциала Терсоффа-Бреннера. Установлено, что они имеют более круглую форму, чем структуры без дефектов. Также рассчитана электронная структура этих фуллеренов с дефектами. Их электронные структуры замкнуты, а энергетические щели между связывающими и антисвязывающими орбиталями больше практически во всех случаях по сравнению с фуллеренами без дефектов