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| Weber, Alexandra Anh-thu; Stohr, Sabine; Chenuil, Anne. |
| Cryptic species are numerous in the marine environment. The brittle star Ophioderma longicauda is composed of six mitochondrial lineages, encompassing brooders, which form a monophyletic group, and broadcasters, from which the brooders are derived. To clarify the species limits within O. longicauda, we compared the reproductive status of the sympatric lineages L1 and L3 (defined after sequencing a portion of the mitochondrial gene COI) during the month of May in Greece. In addition, we genotyped a nuclear marker, intron i51. Each L3 female was brooding, whereas all L1 specimens displayed full gonads, suggesting temporal pre-zygotic isolation between brooders and broadcasters. Statistical differences were found among lineages in morphology and bathymetric... |
| Tipo: Text |
Palavras-chave: Ophiuroidea; Espèces cryptiques; Espèce incubante; Sous-unité I de la cytochrome oxydase; EPIC; Ophiuroidea; Cryptic species; Brooding species; Cytochrome oxidase subunit I; EPIC. |
| Ano: 2014 |
URL: https://archimer.ifremer.fr/doc/00372/48271/48576.pdf |
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| Egbendewe-Mondzozo, Aklesso; Swinton, Scott M.; Izaurralde, R. Cesar; Manowitz, David H.; Zhang, Xuesong. |
| This paper introduces a spatial bioeconomic model for study of potential cellulosic biomass supply at regional scale. By modeling the profitability of alternative crop production practices, it captures the opportunity cost of replacing current crops by cellulosic biomass crops. The model draws upon biophysical crop input-output coefficients, price and cost data, and spatial transportation costs in the context of profit maximization theory. Yields are simulated using temperature, precipitation and soil quality data with various commercial crops and potential new cellulosic biomass crops. Three types of alternative crop management scenarios are simulated by varying crop rotation, fertilization and tillage. The cost of transporting biomass to a specific... |
| Tipo: Working or Discussion Paper |
Palavras-chave: Biomass production; Bioenergy supply; Biofuel policy; Bioenergy; Cellulosic ethanol; Agro-ecosystem economics; Ecosystem services economics; Agro-environmental trade-off analysis; Mathematical programming; EPIC; Agricultural and Food Policy; Crop Production/Industries; Environmental Economics and Policy; Land Economics/Use; Production Economics; Resource /Energy Economics and Policy; Q16; Q15; Q57; Q18. |
| Ano: 2010 |
URL: http://purl.umn.edu/98277 |
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| Heumesser, Christine; Fuss, Sabine; Szolgayova, Jana; Strauss, Franziska; Schmid, Erwin. |
| Irrigated agriculture will play a crucial role to meet future food demand, but a sustainable water resource management in agriculture is crucial as well. Therefore, the European Water Framework Directive promotes several measures, e.g., the adoption of adequate water pricing mechanisms or the promotion of water-saving irrigation techniques. Since production conditions such as weather and climate development are uncertain, farmers might be reluctant to invest in a water-saving but capital intensive irrigation system. We apply a stochastic dynamic programming approach to analyze a farmer’s optimal investment strategy for either a water–saving drip irrigation system or sprinkler irrigation system under weather uncertainty and assess the probability of... |
| Tipo: Conference Paper or Presentation |
Palavras-chave: Irrigation investment; Stochastic dynamic programming approach; Water policies; Weather uncertainty; EPIC; Farm Management; Risk and Uncertainty. |
| Ano: 2011 |
URL: http://purl.umn.edu/114536 |
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| Gassman, Philip W.; Williams, Jimmy R.; Benson, Verel W.; Izaurralde, R. Cesar; Hauck, Larry M.; Jones, C. Allan; Atwood, Jay D.; Kiniry, James R.; Flowers, Joan D.. |
| The development of the field-scale Erosion Productivity Impact Calculator (EPIC) model was initiated in 1981 to support assessments of soil erosion impacts on soil productivity for soil, climate, and cropping conditions representative of a broad spectrum of U.S. agricultural production regions. The first major application of EPIC was a national analysis performed in support of the 1985 Resources Conservation Act (RCA) assessment. The model has continuously evolved since that time and has been applied for a wide range of field, regional, and national studies both in the U.S. and in other countries. The range of EPIC applications has also expanded greatly over that time, including studies of (1) surface runoff and leaching estimates of nitrogen and... |
| Tipo: Working or Discussion Paper |
Palavras-chave: APEX; Carbon sequestration; Climate change; EPIC; Modeling; Soil erosion; Water quality; Research Methods/ Statistical Methods. |
| Ano: 2005 |
URL: http://purl.umn.edu/18372 |
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