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Author Jing, Q.; Bélanger, G.; Baron, V.; Bonesmo, H.; Virkajärvi, P.; Young, D.
Title Regrowth simulation of the perennial grass timothy Type Journal Article
Year 2012 Publication Ecological Modelling Abbreviated Journal Ecol. Model.
Volume 232 Issue Pages (up) 64-77
Keywords biomass; carbohydrate; leaf area index; n uptake; reserve-dependent growth; temperature; nutritive-value; carbohydrate reserves; phleum-pratense; catimo model; leaf-area; nitrogen-fertilization; spring harvest; meadow fescue; tall fescue; growth
Abstract Several process-based models for simulating the growth of perennial grasses have been developed but few include the simulation of regrowth. The model CATIMO simulates the primary growth of timothy (Phleum pratense L), an important perennial forage grass species in northern regions of Europe and North America. Our objective was to further develop the model CATIMO to simulate timothy regrowth using the concept of reserve-dependent growth. The performance of this modified CATIMO model in simulating leaf area index (LAI), biomass dry matter (DM) yield, and N uptake of regrowth was assessed with data from four independent field experiments in Norway, Finland, and western and eastern Canada using an approach that combines graphical comparison and statistical analysis. Biomass DM yield and N uptake of regrowth were predicted at the same accuracy as primary growth with linear regression coefficients of determination between measured and simulated values greater than 0.79, model simulation efficiencies greater than 0.78, and normalized root mean square errors (14-30% for biomass and 24-34% for N uptake) comparable with the coefficients of variation of measured data (1-21% for biomass and 1-25% for N uptake). The model satisfactorily simulated the regrowth LAI but only up to a value of about 4.0. The modified CATIMO model with its capacity to simulate regrowth provides a framework to simulate perennial grasses with multiple harvests, and to explore management options for sustainable grass production under different environmental conditions. Crown Copyright (C) 2012 Published by Elsevier B.V. All rights reserved.
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 0304-3800 ISBN Medium Article
Area Expedition Conference
Notes CropM, LiveM Approved no
Call Number MA @ admin @ Serial 4473
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Author Bennetzen, E.H.; Smith, P.; Soussana, J.-F.; Porter, J.R.
Title Identity-based estimation of greenhouse gas emissions from crop production: case study from Denmark Type Journal Article
Year 2012 Publication European Journal of Agronomy Abbreviated Journal European Journal of Agronomy
Volume 41 Issue Pages (up) 66-72
Keywords kaya identity; kaya-porter identity; crop production; greenhouse gas emission; energy intensity; mitigation; food system; agriculture; mitigation; energy; opportunities; inventory; europe; policy; land
Abstract In order to feed the world we need innovative thinking on how to increase agricultural production whilst also mitigating climate change. Agriculture and land-use change are responsible for approximately one-third of total anthropogenic greenhouse gas (GHG) emissions but hold potential for climate change mitigation but are only tangentially included in UNFCCC mitigation policies. To get a full estimate of GHG emissions from agricultural crop production both energy-based emissions and land-based emissions need to be accounted for. Furthermore, the major mitigation potential is likely to be indirect reduction of emissions i.e. reducing emissions per unit of agricultural product rather than the absolute emissions per se. Hence the system productivity must be included in the same analysis. This paper presents the Kaya-Porter identity, derived from the Maya identity, as a new way to calculate GHG emissions from agricultural crop production by deconstructing emissions into five elements; the GHG intensity of the energy used for production (kg CO2-eq./MJ), energy intensity of the production (MJ/kg dry matter), areal productivity (kg dry matter/ha), areal land-based GHG emissions (CO2-eq./ha) and area (ha). These separate elements in the identity can be targeted in emissions reduction and mitigation policies and are useful to analyse past and current trends in emissions and to explore future scenarios. Using the Kaya-Porter identity we have performed a case study on Danish crop production and find emissions to have been reduced by 12% from 1992 to 2008, whilst yields per unit area have remained constant. Both land-based emissions and energy-based emissions have decreased, mainly due to a 41% reduction in nitrogen fertilizer use. The initial identity based analysis for crop production presented here needs to be extended to include livestock to reflect the entire agricultural production and food demand sectors, thereby permitting analysis of the trade-offs between animal and plant food production, human dietary preferences and population and resulting GHG emissions. (C) 2012 Elsevier B.V. All rights reserved.
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 1161-0301 ISBN Medium Article
Area Expedition Conference
Notes CropM, ftnotmacsur Approved no
Call Number MA @ admin @ Serial 4581
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Author Mueller, L.; Schindler, U.; Shepherd, T.G.; Ball, B.C.; Smolentseva, E.; Hu, C.; Hennings, V.; Schad, P.; Rogasik, J.; Zeitz, J.; Schlindwein, S.L.; Behrendt, A.; Helming, K.; Eulenstein, F.
Title A framework for assessing agricultural soil quality on a global scale Type Journal Article
Year 2012 Publication Archives of Agronomy and Soil Science Abbreviated Journal Archives of Agronomy and Soil Science
Volume 58 Issue sup1 Pages (up) S76-S82
Keywords soil quality; indicators; muencheberg soil quality rating
Abstract This paper provides information about a novel approach of rating agricultural soil quality (SQ) and crop yield potentials consistently over a range of spatial scales. The Muencheberg Soil Quality Rating is an indicator-based straightforward overall assessment method of agricultural SQ. It is a framework covering aspects of soil texture, structure, topography and climate which is based on 8 basic indicators and more than 12 hazard indicators. Ratings are performed by visual methods of soil evaluation. A field manual is then used to provide ratings from tables based on indicator thresholds. Finally, overall rating scores are given, ranging from 0 (worst) to 100 (best) to characterise crop yield potentials. The current approach is valid for grassland and cropland. Field tests in several countries confirmed the practicability and reliability of the method. At field scale, soil structure is a crucial, management induced criterion of agricultural SQ. At the global scale, climate controlled hazard indicators of drought risk and soil thermal regime are crucial for SQ and crop yield potentials. Final rating scores are well correlated with crop yields. We conclude that this system could be evolved for ranking and controlling agricultural SQ on a global scale.
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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 0365-0340 ISBN Medium Article
Area Expedition Conference
Notes CropM, TradeM, ftnotmacsur Approved no
Call Number MA @ admin @ Serial 4589
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Author Kowalczyk, A.; Twardy, S.
Title Comparison of the water erosion magnitude estimated by the modified USLE methods Type Report
Year 2012 Publication Woda Srodowisko Obszary Wiejskie Abbreviated Journal
Volume 121 Issue Pages (up) 83-92
Keywords CropM
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor ITP Falenty Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number MA @ admin @ Serial 2068
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Author Francone, C.; Katul, G.G.; Cassardo, C.; Richiardone, R.
Title Turbulent transport efficiency and the ejection-sweep motion for momentum and heat on sloping terrain covered with vineyards Type Journal Article
Year 2012 Publication Agricultural and Forest Meteorology Abbreviated Journal Agricultural and Forest Meteorology
Volume 162-163 Issue Pages (up) 98-107
Keywords coherent motion; cumulant expansions; heat and momentum transfer; sloping terrain; vineyards; planar fit method; boundary-layers; reynolds stress; dense canopies; plant canopies; flow; fluxes; forest; fields; hills
Abstract In boundary layer flows, it is now recognized that the net momentum and mass exchange rates are dominated by the statistical properties of ejecting and sweeping motion often linked to the presence of coherent turbulent structures. Over vineyards, three main factors impact the transport properties of such coherent motion: presence of sloping terrain, variations in leaf area index (LAI) during the growing season, and thermal stratification. The effect of these factors on momentum and heat transport is explored for three vineyard sites situated on different slopes. All three sites experience similar seasonal variation in LAI and mean wind conditions. The analysis is carried out using a conventional quadrant analysis technique and is tested against two models approximating the joint probability density function (JPDF) of the flow variables. It is demonstrated that a Gaussian JPDF explains much of the updraft and downdraft statistical contributions to heat and momentum transport efficiencies for all three sites. An incomplete or truncated third-order cumulant expansion method (ICEM) of the JPDF that retains only the mixed moments and ignores the skewness contributions describes well all the key properties of ejections and sweeps for all slopes, LAI, and stability classes. The implication of these findings for diagnosing potential failures of gradient-diffusion theory over complex terrain is discussed. Because only lower order moments are needed to describe the main characteristics of the JPDF, the use of the Moving Equilibrium Hypothesis (MEH) to predict these moments from the locally measured sensible heat flux and friction velocity is explored. Provided the planar fit coordinate transformation is applied to the data, the MEH can describe these statistical moments at all three sites regardless of terrain slopes and LAI values. (C) 2012 Elsevier B.V. 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 0168-1923 ISBN Medium Article
Area Expedition Conference
Notes CropM Approved no
Call Number MA @ admin @ Serial 4471
Permanent link to this record