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Taastrup, Denmark

Fedoroff N.,AgroTech | Courty M.-A.,CNRS PROMES | Courty M.-A.,University Rovira i Virgil Plaza Imperial
Turkish Journal of Earth Sciences

This work, aside from being a classical discussion on the processes of rubefaction and illuviation, is an attempt to cross the abundant literature on red Mediterranean soils (RMSs) written by pedologists, and also by paleopedologists and geologists, with the climatic frame established by paleoclimatologists for the Quaternary. Such an approach leads us to consider that the development of the RMSs was discontinuous, occurring during periods of environmental stability, i.e. interglacials, characterized by a humid climate (precipitations exceeding evapotranspiration) with dry and hot summers. The impact of glacial intervals on the RMS covers is presently only partially documented. Aeolian processes during atmospheric instability episodes played a dominant role; however, hydric erosion and resedimentation cannot be ignored. Severe wind storms have reworked the RMS covers locally, but long distance dusts were also incorporated into the soils. Outbursts are proposed to explain the disruption observed in pre-Holocene red B horizons. Calcite from aeolian dusts was dissolved in surface horizons and recrystallized in deeper horizons in the form of discrete features and calcrete. During the more humid phases of these intervals, RMS became waterlogged in presently humid areas of the Mediterranean basin. The impact of frost on the RMS covers has been exaggerated. Precise correlations between the climatic fluctuations identified by paleoclimatologists and features and facies in the soil covers generated during the glacial intervals are almost impossible to establish. © Tübi̇tak. Source

Storm I.M.L.D.,Copenhagen University | Hellwing A.L.F.,University of Aarhus | Nielsen N.I.,AgroTech | Madsen J.,Copenhagen University

This paper is a brief introduction to the different methods used to quantify the enteric methane emission from ruminants. A thorough knowledge of the advantages and disadvantages of these methods is very important in order to plan experiments, understand and interpret experimental results, and compare them with other studies. The aim of the paper is to describe the principles, advantages and disadvantages of different methods used to quantify the enteric methane emission from ruminants. The best-known methods: Chambers/respiration chambers, SF6 technique and in vitro gas production technique and the newer CO2 methods are described. Model estimations, which are used to calculate national budget and single cow enteric emission from intake and diet composition, are also discussed. Other methods under development such as the micrometeorological technique, combined feeder and CH4 analyzer and proxy methods are briefly mentioned. Methods of choice for estimating enteric methane emission depend on aim, equipment, knowledge, time and money available, but interpretation of results obtained with a given method can be improved if knowledge about the disadvantages and advantages are used in the planning of experiments. © 2010 by the authors; licensee MDPI, Basel, Switzerland. Source

Stockmann U.,University of Sydney | Adams M.A.,University of Sydney | Crawford J.W.,University of Sydney | Field D.J.,University of Sydney | And 20 more authors.
Agriculture, Ecosystems and Environment

Soil contains approximately 2344. Gt (1 gigaton = 1 billion tonnes) of organic carbon globally and is the largest terrestrial pool of organic carbon. Small changes in the soil organic carbon stock could result in significant impacts on the atmospheric carbon concentration. The fluxes of soil organic carbon vary in response to a host of potential environmental and anthropogenic driving factors. Scientists worldwide are contemplating questions such as: 'What is the average net change in soil organic carbon due to environmental conditions or management practices?', 'How can soil organic carbon sequestration be enhanced to achieve some mitigation of atmospheric carbon dioxide?' and 'Will this secure soil quality?'. These questions are far reaching, because maintaining and improving the world's soil resource is imperative to providing sufficient food and fibre to a growing population. Additional challenges are expected through climate change and its potential to increase food shortages. This review highlights knowledge of the amount of carbon stored in soils globally, and the potential for carbon sequestration in soil. It also discusses successful methods and models used to determine and estimate carbon pools and fluxes. This knowledge and technology underpins decisions to protect the soil resource. © 2012 Elsevier B.V. Source

Rose-Meierhfer S.,University of Applied Sciences Neubrandenburg | Borsting C.F.,AgroTech | Auer W.,MKW electronics GmbH | Gfllner V.,MKW electronics GmbH | And 2 more authors.
Precision Livestock Farming 2015 - Papers Presented at the 7th European Conference on Precision Livestock Farming, ECPLF 2015

Aim of this investigation was to evaluate the SMARTBOW® (SB). The SMARTBOW® is a wireless local area network for animal position finding and shows in real time the position of the animals (x and y coordinates). Each cow was given an ear tag, completely equipped with state of the art sensor technology. The data were forwarded to a local server, analysed and the position of each animal in the barn was clearly displayed on PC and Smartphone. The SMARTBOW® from the company MKW electronics GmbH was installed in autumn 2013 in the dairy barn of the Danish Cattle Research Centre (KFC). For the first test of precision seven sensors had been placed on different areas in the stable (at a feed bunker, at lying cubicles, in a waiting area in front of the Voluntary Milking System, in the area of pregnant heifers and in a calving-pen). To get an overview about the position of the cows, route maps and scatter plots were drawn up by cows lying in cubicles. The real time positioning of the seven sensors put at a fixed position showed standard deviations for the x-coordinate between 0.46 m and 1.01 m whereas for the y-coordinate standard deviation was between 0.35 m and 1.33 m, respectively. The 13 sensors fixed on the cows lying in cubicles showed standard deviations of cow position in X- and Y-direction between 0,52 and 2,0 m and 0,5 and 1,63 m, respectively. These first results seem practicable for working with animals and the wireless local area network system. Source

Kjaer K.H.,University of Aarhus | Thorup-Kristensen K.,Copenhagen University | Rosenqvist E.,Copenhagen University | Aaslyng J.M.,AgroTech
European Journal of Horticultural Science

Decreasing the night temperature in greenhouse production of plants decrease the energy costs. However, problems may arise as low night temperature (LNT) is known to increase leaf starch contents and delay plant development. In this study it was investigated whether increased CO2 concentrations can decrease the negative effects of LNT, when plants of vegetative Chrysanthemum morifolium 'Coral Charm' are grown under greenhouse conditions. Plants were grown under long day conditions (LD) with a photoperiod of 17 h in four compartments. The four compartments had a day temperature set point of 22 °C, and four combinations of night temperatures and CO2 concentration during the day; the night temperature set points were 20 °C and 12 °C, and set points of CO2 concentrations were, ambient CO2 of 400 μl l-1 and high CO2 of 900 μl l-1. Plants were harvested after 3, 4 and 7 weeks. The leaf carbohydrate contents of the chrysanthemums differed in relation to harvest time and the photon flux density (PFD) measured outside the green-house. Treatments with high CO2 and low night temperature (LNT) increased leaf carbohydrate contents, but the effect was more pronounced at the 7 weeks harvest, where also the PFD was high. Generally, the treatment with high CO2 increased growth in terms of increased shoot dry matter (DM) and the formation of leaves in plants grown at LNT. LNT had the opposite effect decreasing shoot DM production, stem length and leaf number, but only at ambient CO2 concentrations. The results illustrate that when plants are grown in a combination with LNT and high CO2, the accumulation of leaf carbohydrates increases, however plant growth is less limited by the LNT in comparison to plants grown in LNT at ambient CO2 concentrations. It is suggested to include high CO2 concentrations in greenhouse production of Chrysanthemum morifolium, when grown under LNT. © Verlag Eugen Ulmer KG, Stuttgart. Source

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