| Records |
| Author |
Dumont, B.; Basso, B.; Bodson, B.; Destain, J.-P.; Destain, M.-F. |
| Title |
Climatic risk assessment to improve nitrogen fertilisation recommendations: A strategic crop model-based approach |
Type |
Journal Article |
| Year |
2015 |
Publication |
European Journal of Agronomy |
Abbreviated Journal |
European Journal of Agronomy |
| Volume |
65 |
Issue |
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Pages |
10-17 |
| Keywords |
climatic variability; stochastically generated weather; lars-wg; crop model; stics; nitrogen management; yield skewness; wheat yield; generic model; stics; management; variability; simulation; field; balances; impact |
| Abstract |
Within the context of nitrogen (N) management, since 1950, with the rapid intensification of agriculture, farmers have often applied much larger fertiliser quantities than what was required to reach the yield potential. However, to prevent pollution of surface and groundwater induced by nitrates, The European Community launched The European Nitrates Directive 91/6/76/EEC. In 2002, in Wallonia (Belgium), the Nitrates Directive has been transposed under the Sustainable Nitrogen Management in Agriculture Program (PGDA), with the aim of maintaining productivity and revenue for the country’s farmers, while reducing the environmental impact of excessive N application. A feasible approach for addressing climatic uncertainty lies in the use of crop models such as the one commonly known as STICS (simulateur multidisciplinaire pour les cultures standard). These models allow the impact on crops of the interaction between cropping systems and climatic records to be assessed. Comprehensive historical climatic records are rare, however, and therefore the yield distribution values obtained using such an approach can be discontinuous. In order to obtain better and more detailed yield distribution information, the use of a high number of stochastically generated climate time series was proposed, relying on the LARS-Weather Generator. The study focused on the interactions between varying N practices and climatic conditions. Historically and currently, Belgian farmers apply 180 kg N ha(-1), split into three equal fractions applied at the tillering, stem elongation and flag-leaf stages. This study analysed the effectiveness of this treatment in detail, comparing it to similar practices where only the N rates applied at the flag-leaf stage were modified. Three types of farmer decision-making were analysed. The first related to the choice of N strategy for maximising yield, the second to obtaining the highest net revenue, and the third to reduce the environmental impact of potential N leaching, which carries the likelihood of taxation if inappropriate N rates are applied. The results showed reduced discontinuity in the yield distribution values thus obtained. In general, the modulation of N levels to accord with current farmer practices showed considerable asymmetry. In other words, these practices maximised the probability of achieving yields that were at least superior to the mean of the distribution values, thus reducing risk for the farmers. The practice based on applying the highest amounts (60-60-100 kg N ha(-1)) produced the best yield distribution results. When simple economical criteria were computed, the 60-60-80 kg N ha(-1) protocol was found to be optimal for 80-90% of the time. There were no statistical differences, however, between this practice and Belgian farmers’ current practice. When the taxation linked to a high level of potentially leachable N remaining in the soil after harvest was considered, this methodology clearly showed that, in 3 years out of 4,30 kg N ha(-1) could systematically be saved in comparison with the usual practice. |
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English |
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Edition |
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| ISSN |
1161-0301 |
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Notes  |
CropM, ft_macsur |
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no |
| Call Number |
MA @ admin @ |
Serial |
4646 |
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| Author |
Kersebaum, K.C.; Boote, K.J.; Jorgenson, J.S.; Nendel, C.; Bindi, M.; Frühauf, C.; Gaiser, T.; Hoogenboom, G.; Kollas, C.; Olesen, J.E.; Rötter, R.P.; Ruget, F.; Thorburn, P.J.; Trnka, M.; Wegehenkel, M. |
| Title |
Analysis and classification of data sets for calibration and validation of agro-ecosystem models |
Type |
Journal Article |
| Year |
2015 |
Publication |
Environmental Modelling & Software |
Abbreviated Journal |
Env. Model. Softw. |
| Volume |
72 |
Issue |
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Pages |
402-417 |
| Keywords |
field experiments; data quality; crop modelling; data requirement; minimum data; software; different climatic zones; soil-moisture sensors; spatial variability; nitrogen dynamics; crop models; systems simulation; wheat yields; elevated co2; growth; field |
| Abstract |
Experimental field data are used at different levels of complexity to calibrate, validate and improve agroecosystem models to enhance their reliability for regional impact assessment. A methodological framework and software are presented to evaluate and classify data sets into four classes regarding their suitability for different modelling purposes. Weighting of inputs and variables for testing was set from the aspect of crop modelling. The software allows users to adjust weights according to their specific requirements. Background information is given for the variables with respect to their relevance for modelling and possible uncertainties. Examples are given for data sets of the different classes. The framework helps to assemble high quality data bases, to select data from data bases according to modellers requirements and gives guidelines to experimentalists for experimental design and decide on the most effective measurements to improve the usefulness of their data for modelling, statistical analysis and data assimilation. (C) 2015 Elsevier Ltd. All rights reserved. |
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English |
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Edition |
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| ISSN |
1364-8152 |
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Article |
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| Notes |
CropM, ft_macsur |
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no |
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MA @ admin @ |
Serial |
4563 |
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| Author |
Semenov, M.A.; Stratonovitch, P.; Alghabari, F.; Gooding, M.J. |
| Title |
Adapting wheat in Europe for climate change |
Type |
Journal Article |
| Year |
2014 |
Publication |
Journal of Cereal Science |
Abbreviated Journal |
J. Ceareal Sci. |
| Volume |
59 |
Issue |
3 |
Pages |
245-256 |
| Keywords |
A, maximum area of flag leaf area; ABA, abscisic acid; CV, coefficient of variation; Crop improvement; Crop modelling; FC, field capacity; GMT, Greenwich mean time; GS, growth stage; Gf, grain filling duration; HI, harvest index; HSP, heat shock protein; Heat and drought tolerance; Impact assessment; LAI, leaf area index; Ph, phylochron; Pp, photoperiod response; Ru, root water uptake; S, duration of leaf senescence; SF, drought stress factor; Sirius; Wheat ideotype |
| Abstract |
Increasing cereal yield is needed to meet the projected increased demand for world food supply of about 70% by 2050. Sirius, a process-based model for wheat, was used to estimate yield potential for wheat ideotypes optimized for future climatic projections for ten wheat growing areas of Europe. It was predicted that the detrimental effect of drought stress on yield would be decreased due to enhanced tailoring of phenology to future weather patterns, and due to genetic improvements in the response of photosynthesis and green leaf duration to water shortage. Yield advances could be made through extending maturation and thereby improve resource capture and partitioning. However the model predicted an increase in frequency of heat stress at meiosis and anthesis. Controlled environment experiments quantify the effects of heat and drought at booting and flowering on grain numbers and potential grain size. A current adaptation of wheat to areas of Europe with hotter and drier summers is a quicker maturation which helps to escape from excessive stress, but results in lower yields. To increase yield potential and to respond to climate change, increased tolerance to heat and drought stress should remain priorities for the genetic improvement of wheat. |
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English |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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| ISSN |
0733-5210 |
ISBN |
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Medium |
Review |
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Conference |
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| Notes |
CropM, ft_macsur |
Approved |
no |
| Call Number |
MA @ admin @ |
Serial |
4543 |
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| Author |
Kim, Y.; Berger, S.; Kettering, J.; Tenhunen, J.; Haas, E.; Kiese, R. |
| Title |
Simulation of N2O emissions and nitrate leaching from plastic mulch radish cultivation with LandscapeDNDC |
Type |
Journal Article |
| Year |
2014 |
Publication |
Ecological Research |
Abbreviated Journal |
Ecol. Res. |
| Volume |
29 |
Issue |
3 |
Pages |
441-454 |
| Keywords |
biogeochemical modeling; landscapedndc; N2O; nitrate leaching; plastic mulch; nitrous-oxide emissions; semiarid loess plateau; biogeochemical model; soil-erosion; no emissions; forest soils; dndc model; film mulch; china; field |
| Abstract |
Radish is one of the major dry field crops in Asia commonly grown with plastic mulch and high rates of N fertilization, and potentially harming the environment due to N2O emissions and nitrate leaching. Despite the widespread use of plastic mulch, biogeochemical models so far do not yet consider impacts of mulch on soil environmental conditions and biogeochemistry. In this study, we adapted and successfully tested the LandscapeDNDC model against field data by simulating crop growth, C and N turnover and associated N2O emissions as well as nitrate leaching for radish cultivation with plastic mulch and in conjunction with different rates of N fertilization (465-765 kg N ha(-1) year(-1)). Due to the sandy soil texture and monsoon climate, nitrate leaching with rates up to 350 kg N ha(-1) year(-1) was the dominant reason for overall low nitrogen use efficiency (32-43 %). Direct or indirect N2O emissions (calculated from simulated nitrate leaching rates and IPCC EFind = 0.0075) ranged between 2 and 3 kg N ha(-1) year(-1), thus contributing an equal amount to total field emissions of about 5 kg N ha(-1) year(-1). Based on our results, emission factors for direct N2O emissions ranged between 0.004 and 0.005. These values are only half of the IPCC default value (0.01), demonstrating the need of biogeochemical models for developing site and/or region specific EFs. Simulation results also revealed that changes in agricultural management by applying the fertilizer only to the rows would be an efficient mitigation strategy, effectively decreasing field nitrate leaching and N2O emissions by 50-60 %. |
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English |
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Abbreviated Series Title |
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Edition |
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| ISSN |
0912-3814 1440-1703 |
ISBN |
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Article |
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| Notes |
CropM, ft_macsur |
Approved |
no |
| Call Number |
MA @ admin @ |
Serial |
4528 |
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| Author |
Dumont, B.; Basso, B.; Leemans, V.; Bodson, B.; Destain, J.-P.; Destain, M.-F. |
| Title |
Systematic analysis of site-specific yield distributions resulting from nitrogen management and climatic variability interactions |
Type |
Journal Article |
| Year |
2015 |
Publication |
Precision Agriculture |
Abbreviated Journal |
Precision Agric. |
| Volume |
16 |
Issue |
4 |
Pages |
361-384 |
| Keywords |
nitrogen management; climatic variability; lars-wg weather generator; stics soil-crop model; pearson system; probability risk assessment; crop model stics; fertilizer nitrogen; generic model; wheat yield; maize; simulation; skewness; field; agriculture; scenarios |
| Abstract |
At the plot level, crop simulation models such as STICS have the potential to evaluate risk associated with management practices. In nitrogen (N) management, however, the decision-making process is complex because the decision has to be taken without any knowledge of future weather conditions. The objective of this paper is to present a general methodology for assessing yield variability linked to climatic uncertainty and variable N rate strategies. The STICS model was coupled with the LARS-Weather Generator. The Pearson system and coefficients were used to characterise the shape of yield distribution. Alternatives to classical statistical tests were proposed for assessing the normality of distributions and conducting comparisons (namely, the Jarque-Bera and Wilcoxon tests, respectively). Finally, the focus was put on the probability risk assessment, which remains a key point within the decision process. The simulation results showed that, based on current N application practice among Belgian farmers (60-60-60 kgN ha(-1)), yield distribution was very highly significantly non-normal, with the highest degree of asymmetry characterised by a skewness value of -1.02. They showed that this strategy gave the greatest probability (60 %) of achieving yields that were superior to the mean (10.5 t ha(-1)) of the distribution. |
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English |
Summary Language |
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Series Title |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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| ISSN |
1385-2256 |
ISBN |
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Medium |
Article |
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| Notes |
CropM, ft_macsur |
Approved |
no |
| Call Number |
MA @ admin @ |
Serial |
4519 |
| Permanent link to this record |
