Institution
University of Hohenheim
Education•Stuttgart, Germany•
About: University of Hohenheim is a education organization based out in Stuttgart, Germany. It is known for research contribution in the topics: Population & Soil water. The organization has 8585 authors who have published 16406 publications receiving 567377 citations.
Papers published on a yearly basis
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TL;DR: In this article, a choice experiment was applied across 140 households involved in pig breeding in order to assess farmers' preferences and the trade-offs for a list of adaptive and productive traits.
139 citations
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University of Grenoble1, Centre national de la recherche scientifique2, Grinnell College3, Utah State University4, Macquarie University5, Smithsonian Environmental Research Center6, University of California, Davis7, Agro ParisTech8, Institut national de la recherche agronomique9, University of Potsdam10, University of Hohenheim11
TL;DR: It is found that in temperate forest trees the regions of highest occurrence probability are those with high densities but slow intrinsic population growth rates, and the uncertain relationships between demography and occurrence probability suggests caution when linking species distribution and demographic models.
Abstract: Hutchinson defined species' realized niche as the set of environmental conditions in which populations can persist in the presence of competitors. In terms of demography, the realized niche corresponds to the environments where the intrinsic growth rate (r) of populations is positive. Observed species occurrences should reflect the realized niche when additional processes like dispersal and local extinction lags do not have overwhelming effects. Despite the foundational nature of these ideas, quantitative assessments of the relationship between range-wide demographic performance and occurrence probability have not been made. This assessment is needed both to improve our conceptual understanding of species' niches and ranges and to develop reliable mechanistic models of species geographic distributions that incorporate demography and species interactions. The objective of this study is to analyse how demographic parameters (intrinsic growth rate r and carrying capacity K) and population density (N) relate to occurrence probability (Pocc ). We hypothesized that these relationships vary with species' competitive ability. Demographic parameters, density, and occurrence probability were estimated for 108 tree species from four temperate forest inventory surveys (Quebec, Western US, France and Switzerland). We used published information of shade tolerance as indicators of light competition strategy, assuming that high tolerance denotes high competitive capacity in stable forest environments. Interestingly, relationships between demographic parameters and occurrence probability did not vary substantially across degrees of shade tolerance and regions. Although they were influenced by the uncertainty in the estimation of the demographic parameters, we found that r was generally negatively correlated with Pocc , while N, and for most regions K, was generally positively correlated with Pocc . Thus, in temperate forest trees the regions of highest occurrence probability are those with high densities but slow intrinsic population growth rates. The uncertain relationships between demography and occurrence probability suggests caution when linking species distribution and demographic models.
139 citations
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TL;DR: Critical steps in the optimization of procedures for HT plant phenotyping systems are described, which provides guidelines for the setup of HT experimental procedures, which are required for the generation of reliable and reproducible data of phenotypic variation for a broad range of applications.
Abstract: Detailed and standardized protocols for plant cultivation in environmentally controlled conditions are an essential prerequisite to conduct reproducible experiments with precisely defined treatments. Setting up appropriate and well defined experimental procedures is thus crucial for the generation of solid evidence and is thus indispensable for successful plant research. Non-invasive and high throughput (HT) phenotyping technologies offer the opportunity to monitor and quantify performance dynamics of several hundreds of plants at a time. Compared to small scale plant cultivations, HT systems have much higher demands, from a conceptual and a logistic point of view, on experimental design, as well as the actual plant cultivation conditions, and the image analysis and statistical methods for data evaluation. Furthermore, cultivation conditions need to be designed that elicit plant performance characteristics corresponding to those under natural conditions. This manuscript describes critical steps in the optimization of procedures for HT plant phenotyping systems. Starting with the model plant Arabidopsis, HT-compatible methods were tested, and optimized with regard to growth substrate, soil coverage, watering regime, experimental design (considering environmental inhomogeneities) in automated plant cultivation and imaging systems. As revealed by metabolite profiling, plant movement did not affect the plants’ physiological status. Based on these results, procedures for maize HT cultivation and monitoring were established. Variation of maize vegetative growth in the HT phenotyping system did match well with that observed in the field. The presented results outline important issues to be considered in the design of HT phenotyping experiments for model and crop plants. It thereby provides guidelines for the setup of HT experimental procedures, which are required for the generation of reliable and reproducible data of phenotypic variation for a broad range of applications.
138 citations
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TL;DR: Pregnant women or those considering becoming pregnant are generally advised to avoid the intake of vitamin A rich liver and liver foods, based upon unsupported scientific findings, but sufficient intake of β-carotene may be crucial to help improve and maintain adequate vitamin A status and prevention of developmental disorders.
Abstract: Vitamin A is essential for growth and differentiation of a number of cells and tissues. Notably during pregnancy and throughout the breastfeeding period, vitamin A has an important role in the healthy development of the fetus and the newborn, with lung development and maturation being particularly important. The German Nutrition Society (DGE) recommends a 40% increase in vitamin A intake for pregnant women and a 90% increase for breastfeeding women. However, pregnant women or those considering becoming pregnant are generally advised to avoid the intake of vitamin A rich liver and liver foods, based upon unsupported scientific findings. As a result, the provitamin A carotenoid β-carotene remains their essential source of vitamin A. Basic sources of provitamin A are orange and dark green vegetables, followed by fortified beverages which represent between 20% and 40% of the daily supply. The average intake of β-carotene in Germany is about 1.5–2 mg a day. Assuming a vitamin A conversion rate for β-carotene for juices of 4:1, and fruit and vegetables between 12:1 and 26:1; the total vitamin A contribution from β-carotene intake represents 10–15% of the RDA. The American Pediatrics Association cites vitamin A as one of the most critical vitamins during pregnancy and the breastfeeding period, especially in terms of lung function and maturation. If the vitamin A supply of the mother is inadequate, her supply to the fetus will also be inadequate, as will later be her milk. These inadequacies cannot be compensated by postnatal supplementation. A clinical study in pregnant women with short birth intervals or multiple births showed that almost 1/3 of the women had plasma retinol levels below 1.4 µmol/l corresponding to a borderline deficiency. Despite the fact that vitamin A and beta-carotene rich food is generally available, risk groups for low vitamin A supply exist in the western world. It is therefore highly critical to restrict the β-carotene supply from diet, particularly from sources of β-carotene with high consumer acceptance such as fortified juices (e.g. “ACE juices”) or dietary supplements (e.g. multivitamins for pregnant women). For the part of the population unable to meet vitamin A requirements according to the DACH recommendations, sufficient intake of β-carotene may be crucial to help improve and maintain adequate vitamin A status and prevention of developmental disorders. At this time it has to be urgently advised against restricting the β-carotene supply or putting warning labels on β-carotene fortified products. It is, however, highly recommended to improve the available data on nutrient intakes in Germany, especially for pregnant and breastfeeding women. For them, recommendations to be aware of potential nutrient intake inadequacies might prove useful.
138 citations
Authors
Showing all 8665 results
Name | H-index | Papers | Citations |
---|---|---|---|
Robert J. Lefkowitz | 214 | 860 | 147995 |
Patrick O. Brown | 183 | 755 | 200985 |
Mark Stitt | 132 | 456 | 60800 |
Wolf B. Frommer | 105 | 345 | 30918 |
Muhammad Imran | 94 | 3053 | 51728 |
Muhammad Farooq | 92 | 1341 | 37533 |
Yakov Kuzyakov | 87 | 667 | 37050 |
Werner Goebel | 85 | 367 | 26106 |
Ismail Cakmak | 84 | 249 | 25991 |
Reinhold Carle | 84 | 418 | 24858 |
Michael Wink | 83 | 938 | 32658 |
Albrecht E. Melchinger | 83 | 398 | 23140 |
Tilman Grune | 82 | 479 | 30327 |
Volker Römheld | 79 | 231 | 20763 |
Klaus Becker | 79 | 320 | 27494 |