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Author Dumont, B.; Leemans, V.; Mansouri, M.; Bodson, B.; Destain, J.-P.; Destain, M.-F.
Title Parameter identification of the STICS crop model, using an accelerated formal MCMC approach Type Journal Article
Year 2014 Publication Environmental Modelling & Software Abbreviated Journal Env. Model. Softw.
Volume 52 Issue Pages 121-135
Keywords crop model; parameter estimation; bayes; stics; dream; global sensitivity-analysis; simulation-model; nitrogen balances; bayesian-approach; generic model; wheat; prediction; water; optimization; algorithm
Abstract This study presents a Bayesian approach for the parameters’ identification of the STICS crop model based on the recently developed Differential Evolution Adaptive Metropolis (DREAM) algorithm. The posterior distributions of nine specific crop parameters of the STICS model were sampled with the aim to improve the growth simulations of a winter wheat (Triticum aestivum L) culture. The results obtained with the DREAM algorithm were initially compared to those obtained with a Nelder-Mead Simplex algorithm embedded within the OptimiSTICS package. Then, three types of likelihood functions implemented within the DREAM algorithm were compared, namely the standard least square, the weighted least square, and a transformed likelihood function that makes explicit use of the coefficient of variation (CV). The results showed that the proposed CV likelihood function allowed taking into account both noise on measurements and heteroscedasticity which are regularly encountered in crop modelling. (C) 2013 Elsevier Ltd. All rights reserved.
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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 1364-8152 ISBN Medium Article
Area Expedition Conference (up)
Notes CropM Approved no
Call Number MA @ admin @ Serial 4520
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Author Dietrich, J.P.; Schmitz, C.; Lotze-Campen, H.; Popp, A.; Müller, C.
Title Forecasting technological change in agriculture—An endogenous implementation in a global land use model Type Journal Article
Year 2014 Publication Technological Forecasting and Social Change Abbreviated Journal Technological Forecasting and Social Change
Volume 81 Issue Pages 236-249
Keywords Technological change; Land use; Agricultural productivity; Land use intensity; Research and development; land-use; research expenditures; productivity growth; impact; deforestation; forest; yield; Business & Economics; Public Administration
Abstract ► Endogenous technological change in an economic land use model ► Estimation of yield elasticity with respect to investments in technological change ► Projections of future agricultural productivity rates ► Validation with observed data and historic trends ► Trade-off between required technological change and forest protection objectives Technological change in agriculture plays a decisive role for meeting future demands for agricultural goods. However, up to now, agricultural sector models and models on land use change have used technological change as an exogenous input due to various information and data deficiencies. This paper provides a first attempt towards an endogenous implementation based on a measure of agricultural land use intensity. We relate this measure to empirical data on investments in technological change. Our estimated yield elasticity with respect to research investments is 0.29 and production costs per area increase linearly with an increasing yield level. Implemented in the global land use model MAgPIE (“Model of Agricultural Production and its Impact on the Environment”) this approach provides estimates of future yield growth. Highest future yield increases are required in Sub-Saharan Africa, the Middle East and South Asia. Our validation with FAO data for the period 1995–2005 indicates that the model behavior is in line with observations. By comparing two scenarios on forest conservation we show that protecting sensitive forest areas in the future is possible but requires substantial investments into technological change.
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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 0040-1625 ISBN Medium Article
Area Expedition Conference (up)
Notes CropM Approved no
Call Number MA @ admin @ Serial 4518
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Author Bulak, P.; Walkiewicz, A.; Brzezińska, M.
Title Plant growth regulators-assisted phytoextraction Type Journal Article
Year 2014 Publication Biologia Plantarum Abbreviated Journal Biol. Plant.
Volume 58 Issue 1 Pages 1-8
Keywords auxins; cytokinins; gibberelins; heavy metals; phytoremediation; pollutants; Zea-mays l.; heavy-metals; Pteris-vittata; organic-acids; molecular-mechanisms; contaminated soils; Sedum-alfredii; lead uptake; hyperaccumulation; phytoremediation
Abstract Plant growth regulators (PRG)-assisted phytoremediation is a technique that could enhance the yield of heavy metal accumulation in plant tissues. So far, a small number of experiments have helped identify three groups of plant hormones that may be useful for this purpose: auxins, cytokinins, and gibberellins. Studies have shown that these hormones positively affect the degree of accumulation of metallic impurities and improve the growth and stress resistance of plants. This review summarizes the present knowledge about PGRs’ impact on phytoextraction yield.
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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 0006-3134 ISBN Medium Review
Area Expedition Conference (up)
Notes CropM, ft_macsur Approved no
Call Number MA @ admin @ Serial 4515
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Author Challinor, A.; Martre, P.; Asseng, S.; Thornton, P.; Ewert, F.
Title Making the most of climate impacts ensembles Type Journal Article
Year 2014 Publication Nature Climate Change Abbreviated Journal Nat. Clim. Change
Volume 4 Issue 2 Pages 77-80
Keywords uncertainty; model; adaptation
Abstract Increasing use of regionally and globally oriented impacts studies, coordinated across international modelling groups, promises to bring about a new era in climate impacts research. Coordinated cycles of model improvement and projection are needed to make the most of this potential.
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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 1758-678x 1758-6798 ISBN Medium Commentary
Area Expedition Conference (up)
Notes CropM Approved no
Call Number MA @ admin @ Serial 4516
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Author Dáder, B.; Gwynn-Jones, D.; Moreno, A.; Winters, A.; Fereres, A.
Title Impact of UV-A radiation on the performance of aphids and whiteflies and on the leaf chemistry of their host plants Type Journal Article
Year 2014 Publication Journal of Photochemistry and Photobiology B: Biology Abbreviated Journal J. Photochem. Photobiol. B
Volume 138 Issue Pages 307-316
Keywords Amino Acids/analysis; Animals; Aphids/*radiation effects; Capsicum/metabolism/parasitology/radiation effects; Carbohydrates/analysis; Chromatography, High Pressure Liquid; Female; Fertility/radiation effects; Hemiptera/*radiation effects; Mass Spectrometry; Phenols/analysis/chemistry; Plant Leaves/metabolism/parasitology/radiation effects; Plants/parasitology/*radiation effects; Proteins/analysis; Solanum melongena/metabolism/parasitology/radiation effects; Time Factors; *Ultraviolet Rays; Eggplant; Insect pests; Pepper; Plant-insect interactions; UV-blocking covers
Abstract Ultraviolet (UV) radiation directly regulates a multitude of herbivore life processes, in addition to indirectly affecting insect success via changes in plant chemistry and morphogenesis. Here we looked at plant and insect (aphid and whitefly) exposure to supplemental UV-A radiation in the glasshouse environment and investigated effects on insect population growth. Glasshouse grown peppers and eggplants were grown from seed inside cages covered by novel plastic filters, one transparent and the other opaque to UV-A radiation. At a 10-true leaf stage for peppers (53 days) and 4-true leaf stage for eggplants (34 days), plants were harvested for chemical analysis and infested by aphids and whiteflies, respectively. Clip-cages were used to introduce and monitor the insect fitness and populations of the pests studied. Insect pre-reproductive period, fecundity, fertility and intrinsic rate of natural increase were assessed. Crop growth was monitored weekly for 7 and 12 weeks throughout the crop cycle of peppers and eggplants, respectively. At the end of the insect fitness experiment, plants were harvested (68 days and 18-true leaf stage for peppers, and 104 days and 12-true leaf stage for eggplants) and leaves analysed for secondary metabolites, soluble carbohydrates, amino acids, total proteins and photosynthetic pigments. Our results demonstrate for the first time, that UV-A modulates plant chemistry with implications for insect pests. Both plant species responded directly to UV-A by producing shorter stems but this effect was only significant in pepper whilst UV-A did not affect the leaf area of either species. Importantly, in pepper, the UV-A treated plants contained higher contents of secondary metabolites, leaf soluble carbohydrates, free amino acids and total content of protein. Such changes in tissue chemistry may have indirectly promoted aphid performance. For eggplants, chlorophylls a and b, and carotenoid levels decreased with supplemental UV-A over the entire crop cycle but UV-A exposure did not affect leaf secondary metabolites. However, exposure to supplemental UV-A had a detrimental effect on whitefly development, fecundity and fertility presumably not mediated by plant cues as compounds implied in pest nutrition – proteins and sugars – were unaltered.
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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 1011-1344 ISBN Medium Article
Area Expedition Conference (up)
Notes CropM Approved no
Call Number MA @ admin @ Serial 4517
Permanent link to this record