|   | 
Details
   web
Records
Author Mansouri, M.; Destain, M.-F.
Title Predicting biomass and grain protein content using Bayesian methods Type Journal Article
Year 2015 Publication Stochastic Environmental Research and Risk Assessment Abbreviated Journal Stoch. Environ. Res. Risk Assess.
Volume (down) 29 Issue 4 Pages 1167-1177
Keywords crop model; particle filter; prediction; ensemble kalman filter; parameter-estimation; particle filters; decision-support; state estimation; model; nitrogen; navigation; tracking; systems
Abstract This paper deals with the problem of predicting biomass and grain protein content using improved particle filtering (IPF) based on minimizing the Kullback-Leibler divergence. The performances of IPF are compared with those of the conventional particle filtering (PF) in two comparative studies. In the first one, we apply IPF and PF at a simple dynamic crop model with the aim to predict a single state variable, namely the winter wheat biomass, and to estimate several model parameters. In the second study, the proposed IPF and the PF are applied to a complex crop model (AZODYN) to predict a winter-wheat quality criterion, namely the grain protein content. The results of both comparative studies reveal that the IPF method provides a better estimation accuracy than the PF method. The benefit of the IPF method lies in its ability to provide accuracy related advantages over the PF method since, unlike the PF which depends on the choice of the sampling distribution used to estimate the posterior distribution, the IPF yields an optimum choice of this sampling distribution, which also utilizes the observed data. The performance of the proposed method is evaluated in terms of estimation accuracy, root mean square error, mean absolute error and execution times.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1436-3240 1436-3259 ISBN Medium Article
Area Expedition Conference
Notes CropM Approved no
Call Number MA @ admin @ Serial 4664
Permanent link to this record
 

 
Author Schönhart, M.; Sinabell, F.
Title Scenarios for the Austrian agricultural sector until 2025 considering greenhouse gas mitigation Type Conference Article
Year 2015 Publication Jahrbuch der ÖGA Abbreviated Journal
Volume (down) 25 Issue Pages 231-240
Keywords
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference Agrarian Perspectives XXIV, 25th Annual Conference of the Austrian Society of Agricultural Economics, 2015-09-16 to 2015-09-18, Prague
Notes TradeM Approved no
Call Number MA @ admin @ Serial 5028
Permanent link to this record
 

 
Author Heinschink, K.; Sinabell, F.; Tribl, C.
Title Decomposition of variable costs in the Austrian agricultural production Type Conference Article
Year 2015 Publication Jahrbuch der ÖGA Abbreviated Journal
Volume (down) 25 Issue Pages 231-240
Keywords
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference Agrarian Perspectives XXIV, 25th Annual Conference of the Austrian Society of Agricultural Economics, 2015-09-16 to 2015-09-18, Prague
Notes TradeM Approved no
Call Number MA @ admin @ Serial 5029
Permanent link to this record
 

 
Author Lehtonen, H.
Title Evaluating adaptation and the production development of Finnish agriculture in climate and global change Type Journal Article
Year 2015 Publication Agricultural and Food Science Abbreviated Journal Agricultural and Food Science
Volume (down) 24 Issue 3 Pages 219-234
Keywords agricultural sector modelling; economic adjustment; global prices; climate change; finnish agriculture; crop production; land-use; challenge; ensembles; Finland; Europe; policy
Abstract Agricultural product prices and policies influence the development of crop yields under climate change through farm level management decisions. On this basis, five main scenarios were specified for agricultural commodity prices and crop yields. An economic agricultural sector model was used in order to assess the impacts of the scenarios on production, land use and farm income in Finland. The results suggest that falling crop yields, if realized due to low prices and restrictive policies, will result in decreasing crop and livestock production and increasing nutrient surplus. Slowly increasing crop yields could stabilise production and increase farm income. Significantly higher crop prices and yields are required, however, for any marked increase in production in Finland. Cereals production would increase relatively more than livestock production, if there were high prices for agricultural products. This is explained by abundant land resources, a high opportunity cost of labour and policies maintaining current dairy and beef production.
Address 2016-07-22
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1459-6067 ISBN Medium Article
Area Expedition Conference
Notes TradeM, ft_macsur Approved no
Call Number MA @ admin @ Serial 4750
Permanent link to this record
 

 
Author van Bussel, L.G.J.; Stehfest, E.; Siebert, S.; Müller, C.; Ewert, F.
Title Simulation of the phenological development of wheat and maize at the global scale Type Journal Article
Year 2015 Publication Global Ecology and Biogeography Abbreviated Journal Glob. Ecol. Biogeogr.
Volume (down) 24 Issue 9 Pages 1018-1029
Keywords Agricultural management; crop calendars; cultivar; variety characteristics; global crop modelling; global harvest dates; phenology; climate-change; winter-wheat; annual crops; photoperiod sensitivity; geographical variation; temperature; responses; adaptation; cultivars; model
Abstract AimTo derive location-specific parameters that reflect the geographic differences among cultivars in vernalization requirements, sensitivity to day length (photoperiod) and temperature, which can be used to simulate the phenological development of wheat and maize at the global scale. LocationGlobal. Methods Based on crop calendar observations and literature describing the large-scale patterns of phenological characteristics of cultivars, we developed algorithms to compute location-specific parameters to represent this large-scale pattern. Vernalization requirements were related to the duration and coldness of winter, sensitivity to day length was assumed to be represented by the minimum and maximum day lengths occurring at a location, and sensitivity to temperature was related to temperature conditions during the vegetative development phase of the crop. Results Application of the derived location-specific parameters resulted in high agreement between simulated and observed lengths of the cropping period. Agreement was especially high for wheat, with mean absolute errors of less than 3 weeks. In the main maize cropping regions, cropping periods were over- and underestimated by 0.5-1.5 months. We also found that interannual variability in simulated wheat harvest dates was more realistic when accounting for photoperiod effects. Main conclusions The methodology presented here provides a good basis for modelling the phenological characteristics of cultivars at the global scale. We show that current global patterns of growing season length as described in cropping calendars can be largely reproduced by phenology models if location-specific parameters are derived from temperature and day length indicators. Growing seasons can be modelled more accurately for wheat than for maize, especially in warm regions. Our method for computing parameters for phenology models from temperature and day length offers opportunities to improve the simulation of crop productivity by crop simulation models developed for large spatial areas and for long-term climate impact projections that account for adaptation in the selection of varieties
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1466-822x ISBN Medium Article
Area Expedition Conference
Notes CropM, ft_macsur Approved no
Call Number MA @ admin @ Serial 4729
Permanent link to this record