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Author Mansouri, M.; Dumont, B.; Leemans, V.; Destain, M.-F. url  doi
openurl 
  Title Bayesian methods for predicting LAI and soil water content Type Journal Article
  Year 2014 Publication Precision Agriculture Abbreviated Journal Precision Agric.  
  Volume 15 Issue 2 Pages 184-201  
  Keywords crop model; bayes; data assimilation; extended kalman filtering; particle filtering; variational filtering; leaf-area index; parameter-estimation; crop models; moisture; instruments; management; sensors; state  
  Abstract (up) LAI of winter wheat (Triticum aestivum L.) and soil water content of the topsoil (200 mm) and of the subsoil (500 mm) were considered as state variables of a dynamic soil-crop system. This system was assumed to progress according to a Bayesian probabilistic state space model, in which real values of LAI and soil water content were daily introduced in order to correct the model trajectory and reach better future evolution. The chosen crop model was mini STICS which can reduce the computing and execution times while ensuring the robustness of data processing and estimation. To predict simultaneously state variables and model parameters in this non-linear environment, three techniques were used: extended Kalman filtering (EKF), particle filtering (PF), and variational filtering (VF). The significantly improved performance of the VF method when compared to EKF and PF is demonstrated. The variational filter has a low computational complexity and the convergence speed of states and parameters estimation can be adjusted independently. Detailed case studies demonstrated that the root mean square error of the three estimated states (LAI and soil water content of two soil layers) was smaller and that the convergence of all considered parameters was ensured when using VF. Assimilating measurements in a crop model allows accurate prediction of LAI and soil water content at a local scale. As these biophysical properties are key parameters in the crop-plant system characterization, the system has the potential to be used in precision farming to aid farmers and decision makers in developing strategies for site-specific management of inputs, such as fertilizers and water irrigation.  
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  Language English Summary Language Original Title  
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  Series Volume Series Issue Edition  
  ISSN 1385-2256 ISBN Medium Article  
  Area Expedition Conference  
  Notes CropM, ftnotmacsur Approved no  
  Call Number MA @ admin @ Serial 4629  
Permanent link to this record
 

 
Author Popp, A.; Humpenöder, F.; Weindl, I.; Bodirsky, B.L.; Bonsch, M.; Lotze-Campen, H.; Müller, C.; Biewald, A.; Rolinski, S.; Stevanovic, M.; Dietrich, J.P. url  doi
openurl 
  Title Land-use protection for climate change mitigation Type Journal Article
  Year 2014 Publication Nature Climate Change Abbreviated Journal Nat. Clim. Change  
  Volume 4 Issue 12 Pages 1095-1098  
  Keywords avoided deforestation; forest conservation; carbon emissions; co2 emissions; productivity; scarcity; stocks; redd  
  Abstract (up) Land-use change, mainly the conversion of tropical forests to agricultural land, is a massive source of carbon emissions and contributes substantially to global warming(1-3). Therefore, mechanisms that aim to reduce carbon emissions from deforestation are widely discussed, A central challenge is the avoidance of international carbon leakage if forest conservation is not implemented globally’’, Here, We show that forest conservation schemes, even if implemented globally, could lead to another type of carbon leakage by driving cropland expansion in non-forested areas that are not subject to forest conservation schemes (non-forest leakage). These areas have a smaller. but still considerable potential to store carbon(5,6). We show that a global forest policy could reduce carbon emissions by 77 Gt CO2, but would still allow for decreases in carbon stocks of non-forest land by 96 Gt CO2, until 2100 due to non-forest leakage effects. Furthermore; abandonment of agricultural hand and associated carbon uptake through vegetation regrowth is hampered. Effective mitigation measures thus require financing structures and conservation investments that cover the full range of carbon-rich ecosystems. However, our analysis indicates that greater agricultural productivity increases would be needed to compensate for such restrictions on agricultural expansion.  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1758-678x 1758-6798 ISBN Medium Article  
  Area Expedition Conference  
  Notes CropM, LiveM, TradeM Approved no  
  Call Number MA @ admin @ Serial 4540  
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Author Wolf, P.; Holz, K. url  openurl
  Title LandPaKT Type Conference Article
  Year 2014 Publication Abbreviated Journal  
  Volume Issue Pages  
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  Abstract (up) LandPaKT (agricultural techniques: potentials and costs of greenhouse gas mitigation) is a joint project of the Leibniz Institute for Agricultural Engineering (ATB) and the Agricultural-Horticultural Faculty of the Humboldt University Berlin. Within the established graduate school LandPaKT, seven PhD students analyse the mitigation potentials and costs of greenhouse gas emissions systematically and merge them at the farm level. With the re-wetting of organic soils, the carbon sequestration in mineral soils depending on agricultural activities and the livestock husbandry, the most important sectors of agriculture are included in the analyses. With modelling and simulation approaches, single as well as combined measures are analysed with regard to their overall effect. Recommendations for the most-promising measures at farm level are deduced. Based on a farm model for water-use efficiency, developed within another ATB project (AgroHyd), LandPaKT aims to expand the model by greenhouse gas emissions. The graduate school started in May 2013.The increase of the global human population with the resulting increase in food demand accompanied by changed consumption patterns urgently calls for the exploitation of mitigation options in animal husbandry. Based on the Life Cycle Assessment (LCA) approach, methodological recommendations for carbon footprint analyses for dairy farming will be developed. Furthermore, the influence of different feeds and feeding strategies on greenhouse gas emission from dairy farming will be investigated.  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title FACCE MACSUR Mid-term Scientific Conference  
  Series Volume 3(S) Sassari, Italy Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference FACCE MACSUR Mid-term Scientific Conference, 2014-04-01 to 2014-04-04, Sassari, Italy  
  Notes Approved no  
  Call Number MA @ admin @ Serial 5095  
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Author Kipling, R.P.; Saetnan, E.R.; Van den Pol-van Dasselaar, A.; Scollan, N.G. url  openurl
  Title Building modelling capacity for livestock systems: progress in LiveM Type Conference Article
  Year 2014 Publication Abbreviated Journal  
  Volume Issue Pages  
  Keywords  
  Abstract (up) MACSUR provides an opportunity to connect disparate research groups and disciplines in livestock and grassland modelling.  Within the livestock theme (LiveM) of MACSUR, grassland modelling capabilities have been significantly improved through joint modelling exercises, and grassland modellers have exploited their methodological overlaps with CropM to make important contributions to regional pilot studies.  Animal health researchers have been contributing to the southern regional pilot, and modelling resources have been identified for livestock systems at the animal and farm-scales.  Here, the priorities for the next steps for livestock and grassland modelling are discussed, and for the role of MACSUR in addressing the challenges facing the sector.  While crop and grassland modelling deals with primary production, livestock modelling examines the complexity of secondary production. The unique position of livestock modelling presents challenges and opportunities.  The diversity of livestock models (in scale and approach) makes model inter-comparisons and collaborative work challenging, while the range of variables involved in livestock systems provide many opportunities for increasing systemic efficiency and robustness to the impacts of climate change.  Closer integration of experimental research and modelling teams also has the potential to increase the capability of livestock and grassland models to predict the impact of European adaptation strategies on livestock farming systems, and on the contribution of these systems to global food security.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title FACCE MACSUR Mid-term Scientific Conference  
  Series Volume 3(S) Sassari, Italy Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference FACCE MACSUR Mid-term Scientific Conference, 2014-04-01 to 2014-04-04, Sassari, Italy  
  Notes Approved no  
  Call Number MA @ admin @ Serial 5058  
Permanent link to this record
 

 
Author Tao, F.; Zhang, S.; Zhang, Z.; Rötter, R.P. doi  openurl
  Title Maize growing duration was prolonged across China in the past three decades under the combined effects of temperature, agronomic management, and cultivar shift Type Journal Article
  Year 2014 Publication Global Change Biology Abbreviated Journal Glob. Chang. Biol.  
  Volume 20 Issue 12 Pages 3686-3699  
  Keywords Agriculture/*methods; China; *Climate Change; Geography; *Models, Biological; *Temperature; Time Factors; Zea mays/*growth & development; adaptation; agriculture; climate change; crop; cultivar; impacts; phenology  
  Abstract (up) Maize phenology observations at 112 national agro-meteorological experiment stations across China spanning the years 1981-2009 were used to investigate the spatiotemporal changes of maize phenology, as well as the relations to temperature change and cultivar shift. The greater scope of the dataset allows us to estimate the effects of temperature change and cultivar shift on maize phenology more precisely. We found that maize sowing date advanced significantly at 26.0% of stations mainly for spring maize in northwestern, southwestern and northeastern China, although delayed significantly at 8.0% of stations mainly in northeastern China and the North China Plain (NCP). Maize maturity date delayed significantly at 36.6% of stations mainly in the northeastern China and the NCP. As a result, duration of maize whole growing period (GPw) was prolonged significantly at 41.1% of stations, although mean temperature (Tmean) during GPw increased at 72.3% of stations, significantly at 19.6% of stations, and Tmean was negatively correlated with the duration of GPw at 92.9% of stations and significantly at 42.9% of stations. Once disentangling the effects of temperature change and cultivar shift with an approach based on accumulated thermal development unit, we found that increase in temperature advanced heading date and maturity date and reduced the duration of GPw at 81.3%, 82.1% and 83.9% of stations on average by 3.2, 6.0 and 3.5 days/decade, respectively. By contrast, cultivar shift delayed heading date and maturity date and prolonged the duration of GPw at 75.0%, 94.6% and 92.9% of stations on average by 1.5, 6.5 and 6.5 days/decade, respectively. Our results suggest that maize production is adapting to ongoing climate change by shift of sowing date and adoption of cultivars with longer growing period. The spatiotemporal changes of maize phenology presented here can further guide the development of adaptation options for maize production in near future.  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1354-1013 ISBN Medium Article  
  Area Expedition Conference  
  Notes CropM, ft_macsur Approved no  
  Call Number MA @ admin @ Serial 4544  
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