889 resultados para Agricultural production indicators


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Glacial-interglacial changes in sedimentary d15N over the last 120 kyr display a remarkably similar pattern in timing and amplitude in core records extending from the denitrification zone in the eastern tropical North Pacific (ETNP), where subsurface denitrification is active, to the Oregon margin, where no denitrification occurs today. Low d15N values (4-6 per mil) generally characterize glacial stages 2 and 4, and higher d15N values (7-10 per mil) are representative of the Holocene, millennial-scale periods within stage 3, and stage 5. The inferred synchroneity of d15N variations along the entire margin implies that the nitrate isotopic signal produced in the oxygen-poor subsurface waters in the ETNP is rapidly advected northward and recorded at sites far beyond the boundaries of the modern denitrification zone. Similar to d15N, primary production indicators (percent Corg, Ba/Al, and percent opal) show glacial-interglacial as well as millennial-scale variations along the NE Pacific margin, with higher primary production during warm periods. However, the relative phasing between d15N and paleoproduction tracers within individual records changes latitudinally. Whereas d15N and primary production vary approximately synchronously in the midlatitudes, production lags d15N in the ETNP by several kiloyears. This lag calls for a new understanding of the processes driving denitrification in the ETNP. We suggest that oxygen input by the Equatorial Undercurrent as well as local organic matter flux controls denitrification rates in the ETNP. Moreover, the differences in relative timing point to a time-transgressive development of upwelling-favorable winds along the NE Pacific margin after the last glaciation, with those in the north developing several kiloyears earlier.

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Data compiled within the IMPENSO project. The Impact of ENSO on Sustainable Water Management and the Decision-Making Community at a Rainforest Margin in Indonesia (IMPENSO), http://www.gwdg.de/~impenso, was a German-Indonesian research project (2003-2007) that has studied the impact of ENSO (El Nino-Southern Oscillation) on the water resources and the agricultural production in the PALU RIVER watershed in Central Sulawesi. ENSO is a climate variability that causes serious droughts in Indonesia and other countries of South-East Asia. The last ENSO event occurred in 1997. As in other regions, many farmers in Central Sulawesi suffered from reduced crop yields and lost their livestock. A better prediction of ENSO and the development of coping strategies would help local communities mitigate the impact of ENSO on rural livelihoods and food security. The IMPENSO project deals with the impact of the climate variability ENSO (El Niño Southern Oscillation) on water resource management and the local communities in the Palu River watershed of Central Sulawesi, Indonesia. The project consists of three interrelated sub-projects, which study the local and regional manifestation of ENSO using the Regional Climate Models REMO and GESIMA (Sub-project A), quantify the impact of ENSO on the availability of water for agriculture and other uses, using the distributed hydrological model WaSiM-ETH (Sub-project B), and analyze the socio-economic impact and the policy implications of ENSO on the basis of a production function analysis, a household vulnerability analysis, and a linear programming model (Sub-project C). The models used in the three sub-projects will be integrated to simulate joint scenarios that are defined in collaboration with local stakeholders and are relevant for the design of coping strategies.

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This paper investigates the impact of land rental market development on the efficiency of labor allocation and land utilization in rural China. To test the hypothesis that the shadow wage of a rent-in household with limited off-farm opportunities will increase with the development of a land rental market for households, a statistical comparison between the shadow wage and the estimated market wage was conducted. The results showed that the shadow wage for both rent-in households and non-rent-in households was significantly lower than the market wage, but that the wage for the rent-in households was statistically higher than that for non-rent-in households in Fenghua and Deqing, the two counties surveyed in this study. In addition, the estimated marginal product of farmland for rent-in households was statistically higher than the actual land rent that those households paid, while a null hypothesis that the actual rental fee accepted by rent-out households is equivalent to the marginal product of farmland for those households was not rejected in Fenghua county where land transactions by mutual agreement were more prevalent. These results indicate that the development of the land rental market facilitates the efficiency of labor allocation and farmland utilization in rural China.

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This study examines the significance of food crop diversification as a household risk mitigating strategy to achieve "self-sufficiency" to ensure food security during the civil conflict in Cote d’Ivoire. The main motivation for seeking self-sufficiency stems from the fact that during the period of heightened tension due to conflict, the north–south divide set by the UN peacekeeping line disrupted the agricultural supply chain from the food surplus zone, Savane in the north. While we theoretically predict a positive effect on crop diversification because of interrupted food supply chain, we also consider a negative effect due to the covariate shocks. We find robust and statistically significant empirical outcomes supporting such claims. The baseline outcomes withstand a series of robustness checks. The net effect of conflict on crop diversification is positive but not statistically significant. In addition, we find that increasing vulnerability to poverty and food insecurity during conflict seems to be the underlying factors that motivate farm households to adopt such coping strategies.

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To enhance Chinese agricultural production, improve food quality, build consumer trust, and encourage the export of agricultural products, the Chinese government designed the Chinese version of Good Agricultural Practice (ChinaGAP) based on the main principles of the GlobalGAP combining the current Chinese agricultural production situation. This paper studies the characteristics of the ChinaGAP and focusing on the diffusion of the standard using qualitative analysis. Relevant policy recommendations are given based on the Chinese agricultural production status. Previous studies mainly focused on the role of the government. However this paper makes specific suggestions to particular stakeholders in the standard making and diffusion process.

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Free people association constructed from button to above to get better conditions of people using local resources, are among others, elements of local development. LEADER (Liaisons HQWUH DFWLYLWpV GH 'HYHORSHPHQW GH /¶(FRQRPLH 5XUDO) is the Europe Union model of rural development. The LEADER method is conformed in seven features which are factors of success in the approach of applying in different territories . The actions held in the municipal council of rural development of San Andres C a l p a n during 2010 showed some elements of LEADER for it´s adjustment: 1).- territory definition , 2).- local association , 3).- financing. It´s used a methodology consists of reviewing documents about the financing and association in the territory studied, survey applying t define the model of agricultural production and development along with mayors of different municipalities, the economical and social actors. The definition performance field with territory integration of citizen councils as groups of local action and a financing strategy are part of the results of this process of adapting in this territory

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Tablas de Daimiel National Park is located in the Upper Guadiana Basin and represents one of the largest and most important wetlands in Europe. The long term ecological integrity of this wetland is inherently associated with the maintenance of a shallow groundwater table, namely the Western Mancha aquifer (WMA) or Aquifer 23. The intensive use of groundwater, mainly for irrigation, has led over the last decades to deep socio‐economic changes. Such intensive use has also lowered the water table of Aquifer 23, drastically reducing the flooded area of the wetland and threatening its ecological integrity. A number of plans and measures have been developed and implemented since the declaration of overexploitation of Aquifer 23 in the year 1987. The most recent one is the Special Plan for the Upper Guadiana (SPUG), approved in 2008. This Plan is the main measure to comply with achieving the objective of good quantitative and qualitative status required under the Water Framework Directive (2000). This paper offers a new type of integrated analysis which allows assessing under a common lens the physical, economic and social dimensions of groundwater use in the area. The first objective is to calculate the groundwater footprint of agricultural production in the Upper Guadiana basin and its evolution during 2000‐2008. For this purpose, we have applied the Extended Water Footprint (EWF) methodology ‐a novel approach based on the classical Water Footprint (WF) approach‐ that includes an assessment of the water productivity from an economic and social perspective. Compared to the classical WF, the EWF allows for a more complete overview of the sector, providing new insights for policy decisions (e.g. to define options and possibilities on water re‐allocation in order to achieve both better ecosystem conservation and social equity). The second objective is to use the EWF to compare the existing authorized and non‐authorized or illegal use of water. This allows us to discuss current initiatives by public authorities in relation to the existing frame of water rights

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Soil salinity and salt leaching are a risk for sustainable agricultural production in many irrigated areas. This study was conducted over 3.5 years to determine how replacing the usual winter fallow with a cover crop (CC) affects soil salt accumulation and salt leaching in irrigated systems. Treatments studied during the period between summer crops were: barley (Hordeum vulgare L.), vetch (Vicia villosa L.) and fallow. Soil water content was monitored daily to a depth of 1.3 m and used with the numerical model WAVE to calculate drainage. Electrical conductivity (EC) was measured in soil solutions periodically, and in the soil saturated paste extracts before sowing CC and maize. Salt leaching was calculated multiplying drainage by total dissolved salts in the soil solution, and use to obtain a salt balance. Total salt leaching over the four winter fallow periods was 26 Mg ha−1, whereas less than 18 Mg ha−1 in the presence of a CC. Periods of salt gain occurred more often in the CC than in the fallow. By the end of the experiment, net salt losses occurred in all treatments, owing to occasional periods of heavy rainfall. The CC were more prone than the fallow to reduce soil salt accumulation during the early growth stages of the subsequent cash crop.

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Soil salinity and salt leaching are a risk for sustainable agricultural production in many irrigated areas. This study was conducted over 3.5 years to determine how replacing the usual winter fallow with a cover crop (CC) affects soil salt accumulation and salt leaching in irrigated systems. Treatments studied during the period between summer crops were: barley (Hordeum vulgare L.), vetch (Vicia villosa L.) and fallow. Soil water content was monitored daily to a depth of 1.3 m and used with the numerical model WAVE to calculate drainage. Electrical conductivity (EC) was measured in soil solutions periodically, and in the soil saturated paste extracts before sowing CC and maize. Salt leaching was calculated multiplying drainage by total dissolved salts in the soil solution, and use to obtain a salt balance. Total salt leaching over the four winter fallow periods was 26 Mg ha−1, whereas less than 18 Mg ha−1 in the presence of a CC. Periods of salt gain occurred more often in the CC than in the fallow. By the end of the experiment, net salt losses occurred in all treatments, owing to occasional periods of heavy rainfall. The CC were more prone than the fallow to reduce soil salt accumulation during the early growth stages of the subsequent cash crop.

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The economic evaluation of drought impacts is essential in order to define efficient and sustainable management and mitigation strategies. The aim of this study is to evaluate the economic impacts of a drought event on the agricultural sector and measure how they are transmitted from primary production to industrial output and related employment. We fit econometric models to determine the magnitude of the economic loss attributable to water storage. The direct impacts of drought on agricultural productivity are measured through a direct attribution model. Indirect impacts on agricultural employment and the agri-food industry are evaluated through a nested indirect attribution model. The transmission of water scarcity effects from agricultural production to macroeconomic variables is measured through chained elasticities. The models allow for differentiating the impacts deriving from water scarcity from other sources of economic losses. Results show that the importance of drought impacts are less relevant at the macroeconomic level, but are more significant for those activities directly dependent on water abstractions and precipitation. From a management perspective, implications of these findings are important to develop effective mitigation strategies to reduce drought risk exposure.

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La gestión de hábitat orientada a la conservación de polinizadores en los agro-ecosistemas requiere una selección de especies vegetales atendiendo fundamentalmente a dos criterios: i) el potencial atractivo de sus flores a los polinizadores; y ii) la simplicidad en su manejo agronómico. Además de estas premisas, es necesario considerar la capacidad invasora de estas especies vegetales, debido a que algunas de las más atractivas pueden resultar invasoras en determinados agro-ecosistemas. Por lo tanto, es preciso determinar qué especies vegetales son las más indicadas para ser implementadas en cada agro-ecosistema. En la presente tesis doctoral se plantea la búsqueda de las especies vegetales adecuadas para atraer polinizadores en los agro-ecosistemas del centro de España. En una primera aproximación, se ha evaluado la atracción y expansión espacial (potencial invasivo) de seis plantas perennes de la familia Lamiaceae (aromáticas), elegidas por ser nativas de la región mediterránea. La elección de las especies vegetales se ha llevado a cabo con el fin de crear márgenes funcionales basados en la mezcla de especies vegetales con distintos periodos de floración, de modo que prolonguen la disponibilidad de recursos florales en el tiempo. Tras un primer año dedicado al establecimiento de las especies aromáticas, en los dos años siguientes se ha estudiado la atracción individual y combinada de las especies vegetales sobre los polinizadores, y como ésta se ve afectada por la densidad y la morfología floral, utilizando para ello un diseño experimental en bloques al azar. Los resultados de este estudio han puesto de manifiesto que la morfología floral no tuvo influencia sobre la atracción de las especies vegetales, pero si la densidad floral, puesto que las especies vegetales con mayor densidad de flores (Nepeta tuberosa e Hyssopus officinalis) han mostrado mayor atracción a polinizadores. Cabe destacar que de las seis especies consideradas, dos especies de verano (Melissa officinalis y Thymbra capitata) no han contribuido de forma efectiva a la atracción de la mezcla hacia los polinizadores, mostrando una reducción significativa de este parámetro respecto a las otras especies aromáticas a lo largo del verano. Se ha observado que ninguna de las especies aromáticas evaluadas ha mostrado tendencia invasora a lo largo del estudio. En base a estos resultados, se puede concluir que entre las especies aromáticas estudiadas, N. tuberosa, H. officinalis y Salvia verbenaca son las que ofrecen mayor potencial para ser utilizadas en la conservación de polinizadores. De forma similar al caso de las plantas aromáticas, se ha llevado a cabo una segunda experimentación que incluía doce plantas anuales con floración de primavera, en la que se evaluó la atracción a polinizadores y su comportamiento agronómico. Este estudio con especies herbáceas se ha prolongado durante dos años, utilizando un diseño experimental de bloques aleatorios. Las variables analizadas fueron: el atractivo de las distintas especies vegetales a los polinizadores, su eficiencia de atracción (calculada como una combinación de la duración de la floración y las visitas de insectos), su respuesta a dos tipos de manejo agronómico (cultivo en mezcla frente a monocultivo; laboreo frente a no-laboreo) y su potencial invasivo. Los resultados de esta segunda experimentación han mostrado que las flores de Borago officinalis, Echium plantagineum, Phacelia tanacetifolia y Diplotaxis tenuifolia son atractivas a las abejas, mientras que las flores de Calendula arvensis, Coriandrum sativum, D. tenuifolia y Lobularia maritima son atractivas a los sírfidos. Con independencia del tipo de polinizadores atraídos por cada especie vegetal, se ha observado una mayor eficiencia de atracción en parcelas con monocultivo de D. tenuifolia respecto a las parcelas donde se cultivó una mezcla de especies herbáceas, si bien en estas últimas se observó mayor eficiencia de atracción que en la mayoría de parcelas mono-específicas. Respecto al potencial invasivo de las especies herbáceas, a pesar de que algunas de las más atractivas a polinizadores (P. tanacetifolia and C. arvensis) mostraron tendencia a un comportamiento invasor, su capacidad de auto-reproducción se vio reducida con el laboreo. En resumen, D. tenuifolia es la única especie que presentó una alta eficiencia de atracción a distintos tipos de polinizadores, conjuntamente con una alta capacidad de auto-reproducción pero sin mostrar carácter invasor. Comparando el atractivo de las especies vegetales utilizadas en este estudio sobre los polinizadores, D. tenuifolia es la especie más recomendable para su cultivo orientado a la atracción de polinizadores en agro-ecosistemas en el centro de España. Esta especie herbácea, conocida como rúcula, tiene la ventaja añadida de ser una especie comercializada para el consumo humano. Además de su atractivo a polinizadores, deben considerarse otros aspectos relacionados con la fisiología y el comportamiento de esta especie vegetal en los agro-ecosistemas antes de recomendar su cultivo. Dado que el cultivo en un campo agrícola de una nueva especie vegetal implica unos costes de producción, por ejemplo debidos a la utilización de agua de riego, es necesario evaluar el incremento en dichos costes en función de demanda hídrica específica de esa especie vegetal. Esta variable es especialmente importante en zonas dónde se presentan sequías recurrentes como es el caso del centro y sur-este de la península Ibérica. Este razonamiento ha motivado un estudio sobre los efectos del estrés hídrico por sequía y el estrés por déficit moderado y severo de riego sobre el crecimiento y floración de la especie D. tenuifolia, así como sobre la atracción a polinizadores. Los resultados muestran que tanto el crecimiento y floración de D. tenuifolia como su atracción a polinizadores no se ven afectados si la falta de riego se produce durante un máximo de 4 días. Sin embargo, si la falta de riego se extiende a lo largo de 8 días o más, se observa una reducción significativa en el crecimiento vegetativo, el número de flores abiertas, el área total y el diámetro de dichas flores, así como en el diámetro y longitud del tubo de la corola. Por otro lado, el estudio pone de manifiesto que un déficit hídrico regulado permite una gestión eficiente del agua, la cual, dependiendo del objetivo final del cultivo de D. tenuifolia (para consumo o solo para atracción de polinizadores), puede reducir su consumo entre un 40 y un 70% sin afectar al crecimiento vegetativo y desarrollo floral, y sin reducir significativamente el atractivo a los polinizadores. Finalmente, esta tesis aborda un estudio para determinar cómo afecta el manejo de hábitat a la producción de los cultivos. En concreto, se ha planteado una experimentación que incluye márgenes mono-específicos y márgenes con una mezcla de especies atractivas a polinizadores, con el fin de determinar su efecto sobre la producción del cultivo de cilantro (C. sativum). La elección del cultivo de cilantro se debe a que requiere la polinización de insectos para su reproducción (aunque, en menor medida, puede polinizarse también por el viento), además de la facilidad para estimar su producción en condiciones semi-controladas de campo. El diseño experimental consistía en la siembra de márgenes mono-específicos de D. tenuifolia y márgenes con mezcla de seis especies anuales situados junto al cultivo de cilantro. Estos cultivos con márgenes florales fueron comparados con controles sin margen floral. Además, un segundo grupo de plantas de cilantro situadas junto a todos los tratamientos, cuyas flores fueron cubiertas para evitar su polinización, sirvió como control para evaluar la influencia de los polinizadores en la producción del cultivo. Los resultados muestran que la presencia de cualquiera de los dos tipos de margen floral mejora el peso y el porcentaje de germinación de las semillas de cilantro frente al control sin margen. Si se comparan los dos tipos de margen, se ha observado un mayor número de semillas de cilantro junto al margen con mezcla de especies florales respecto al margen mono-específico, probablemente debido al mayor número visitas de polinizadores. Puesto que el experimento se realizó en condiciones de campo semi-controladas, esto sugiere que las visitas de polinizadores fueron el factor determinante en los resultados. Por otro lado, los resultados apuntan a que la presencia de un margen floral (ya sea mono-especifico o de mezcla) en cultivos de pequeña escala puede aumentar la producción de cilantro en más de un 200%, al tiempo que contribuyen a la conservación de los polinizadores. ABSTRACT Habitat management, aimed to conserve pollinators in agro-ecosystems, requires selection of the most suitable plant species in terms of their attractiveness to pollinators and simplicity of agronomic management. However, since all flowers are not equally attractive to pollinators and many plant species can be weedy or invasive in the particular habitat, it is important to test which plant species are the most appropriate to be implemented in specific agro-ecosystems. For that reason, this PhD dissertation has been focused on determination of the most appropriate aromatic and herbaceous plants for conservation of pollinators in agro-ecosystems of Central Spain. Therefore, in a first approximation, spatial expansion (i.e. potential weediness) and attractiveness to pollinators of six aromatic perennial plants from the Lamiaceae family, native and frequent in the Mediterranean region, were evaluated. Preliminary plant selection was based on designing a functional mixed margins consisting of plants attractive to pollinators and with different blooming periods, in order to extend the availability of floral resources in the field. After a year of vegetative growth, the next two years the plant species were studied in a randomized block design experiment in order to estimate their attractiveness to pollinators in Central Spain and to investigate whether floral morphology and density affect attractiveness to pollinators. The final aim of the study was to evaluate how their phenology and attractiveness to pollinators can affect the functionality of a flowering mixture of these plants. In addition, the spatial expansion, i.e. potential weediness, of the selected plant species was estimated under field conditions, as the final purpose of the studied plants is to be implemented within agro-ecosystems. The results of the experiment showed that floral morphology did not affect the attractiveness of plants to pollinators, but floral density did, as plant species with higher floral density (i.e. Nepeta tuberosa and Hyssopus officinalis) showed significantly higher attractiveness to pollinators. In addition, of six plant species, two summer species (Melissa officinalis and Thymbra capitata) did not efficiently contribute to the attractiveness of the mixture to pollinators, which reduced its attractiveness during the summer period. Finally, as none of the plants showed weedy behaviour under field conditions, the attractive plant species, i.e. N. tuberosa, H. officinalis and the early spring flowering Salvia verbenaca, showed good potential to conserve the pollinators. Similarly, in a second approximation, the attractiveness to pollinators and agronomic behaviour of twelve herbaceous plants blooming in spring were studied. This experiment was conducted over two years in a randomized block design in order to evaluate attractiveness of preselected plant species to pollinators, as well as their attractiveness efficiency (a combination of duration of flowering and insect visitation), their response to two different agronomic management practices (growing in mixed vs. mono-specific plots; tillage vs. no-tillage), and their potential weediness. The results of this experiment showed that the flowers of Borago officinalis, Echium plantagineum, Phacelia tanacetifolia and Diplotaxis tenuifolia were attractive to bees, while Calendula arvensis, Coriandrum sativum, D. tenuifolia and Lobularia maritima were attractive to hoverflies. In addition, floral mixture resulted in lower attractiveness efficiency to pollinators than mono-specific D. tenuifolia, but higher than most of the mono-specific stands. On the other hand, although some of the most attractive plant species (e.g. P. tanacetifolia and C. arvensis) showed potential weediness, their self-seeding was reduced by tillage. After comparing attractiveness efficiency of various herbaceous species to pollinators and their potential weediness, the results indicated that D. tenuifolia showed the highest attractiveness efficiency to pollinators and efficient self-reproduction, making it highly recommended to attract bees and hoverflies in agro-ecosystems of Central Spain. In addition, this plant, commonly known as wild rocket, has a supplementary economic value as a commercialized crop. The implementation of a new floral margin in agro-ecosystems means increased production costs, especially in regions with frequent and long droughts (as it is Central and South-East area of Iberian Peninsula), where the principal agricultural cost is irrigation. Therefore, before recommending D. tenuifolia for sustainable habitat management within agro-ecosystems, it is necessary to study the effect of drought stress and moderate and severe deficit irrigation on its growth, flower development and attractiveness to pollinators. The results of this experiment showed that in greenhouse conditions, potted D. tenuifolia could be without irrigation for 4 days without affecting its growth, flowering and attractiveness to pollinators. However, lack of irrigation for 8 days or longer significantly reduced the vegetative growth, number of open flowers, total floral area, flower diameter, corolla tube diameter and corolla tube length of D. tenuifolia. This study showed that regulated deficit irrigation can improve water use efficiency, and depending on the purpose of growing D. tenuifolia, as a crop or as a beneficial plant to attract pollinators, it can reduce water consumption by 40% to 70% without affecting its vegetative and floral development and without reducing its attractiveness to pollinators. Finally, the following experiment was developed in order to understand how habitat management can influence on the agricultural production. For this purpose, it was evaluated if the vicinity of mixed and mono-specific field margins, preselected to conserve pollinators within agro-ecosystems, can improve seed production in coriander (C. sativum). The selection of this plant species for the experiment was based on its necessity for insect pollination for production of seeds (even though some pollen can be transmitted from one flower to another by wind) and the fact that under semi-controlled field conditions established in the field it is possible to estimate its total seed production. Since D. tenuifolia is attractive for both bees and hoverflies in Central Spain, the main objective of this experiment was to estimate the impact of two different types of field margins, i.e. mono-specific margin with D. tenuifolia and mixed margin with six herbaceous species, on the seed production of potted coriander. For that reason, it was tested: i) if open pollination (control without proximate field margin and treatments with nearby mono-specific and mixed margin) increases the seed production of coriander when compared with no-pollination (covered inflorescences of coriander) under field conditions; ii) if frequency of pollinator visitation to the flowers of coriander was higher in the presence of field margins than in the control without field margin; and iii) if seed production was higher in the presence of field margins than in control plants of coriander without field margin. The results showed that the proximity of both types of floral margins (mixed and mono-specific) improved the seed quality of coriander plants, as seed weight and germination rate were higher than in control plants without field margin. Furthermore, the number of seeds produced was significantly higher in coriander plants grown near mixed margins than near mono-specific margin, probably due to an increase in pollinator visits. Since the experiment was conducted under semi-controlled field conditions, it can be concluded that pollinator visits was the main factor that biased the results, and that presence of both mixed or mono-specific (D. tenuifolia) margins can improve the production of coriander for more than 200% in small-scale gardens and, in addition, conserve the local pollinators.

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This study analyses the structure of air traffic and its distribution among the different countries in the European Union, as well as traffic with an origin or destination in non-EU countries. Data sources are Eurostat statistics and actual flight information from EUROCONTROL. Relevant variables such as the number of flights, passengers or cargo tonnes and production indicators (RPKs) are used together with fuel consumption and CO2 emissions data. The segmentation of air traffic in terms of distance permits an assessment of air transport competition with surface transport modes. The results show a clear concentration of traffic in the five larger countries (France, Germany, Italy, Spain and UK), in terms of RPKs. In terms of distance the segment between 500 and 1000 km in the EU, has more flights, passengers, RTKs and CO2 emissions than larger distances. On the environmental side, the distribution of CO2 emissions within the EU Member States is presented, together with fuel efficiency parameters. In general, a direct relationship between RPKs and CO2 emissions is observed for all countries and all distance bands. Consideration is given to the uptake of alternative fuels. Segmenting CO2 emissions per distance band and aircraft type reveals which flights contribute the most the overall EU CO2 emissions. Finally, projections for future CO2 emissions are estimated, according to three different air traffic growth and biofuel introduction scenarios.

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Climate Change, Water Scarcity in Agriculture and the Country-Level Economic Impacts. A Multimarket Analysis. Abstract: Agriculture could be one of the most vulnerable economic sectors to the impacts of climate change in the coming decades. Considering the critical role that water plays for agricultural production, any shock in water availability will have great implications for agricultural production, land allocation, and agricultural prices. In this paper, an Agricultural Multimarket model is developed to analyze climate change impacts in developing countries, accounting for the uncertainty associated with the impacts of climate change. The model has a structure flexible enough to represent local conditions, resource availability, and market conditions. The results suggest different economic consequences of climate change depending on the specific activity, with many distributional effects across regions

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Extreme events of maximum and minimum temperatures are a main hazard for agricultural production in Iberian Peninsula. For this purpose, in this study we analyze projections of their evolution that could be valid for the next decade, represented in this study by the 30-year period 2004-2034 (target period). For this purpose two kinds of data were used in this study: 1) observations from the station network of AEMET (Spanish National Meteorological Agency) for five Spanish locations, and 2) simulated data at a resolution of 50 50 km horizontal grid derived from the outputs of twelve Regional Climate Models (RCMs) taken from project ENSEMBLES (van der Linden and Mitchell, 2009), with a bias correction (Dosio and Paruolo, 2011; Dosio et al., 2012) regarding the observational dataset Spain02 (Herrera et al., 2012). To validate the simulated climate, the available period of observations was compared to a baseline period (1964-1994) of simulated climate for all locations. Then, to analyze the changes for the present/very next future, probability of extreme temperature events for 2004-2034 were compared to that of the baseline period. Although only minor changes are expected, small variations in variability may have a significant impact in crop performance.

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Per capita food availability in the developing world has increased by 20% since the early 1960s, according to the Food and Agriculture Organization, and today the world has twice as many people but 150 million fewer hungry people than in 1960. The world agricultural system has not done too bad a job over the past 35 years. It is likely that global agricultural production will continue to at least match growth in food demand over the next decade, assuming no major weather anomalies. Continued support of the Consultative Group for International Agricultural Research and programs involving U.S. universities is important to sharing knowledge about agriculture with colleagues in the developing world. This paper explores the reasons for providing agricultural development assistance, the benefits to the United States that come from doing so, and the special challenges facing the world over the next few decades.