|   | 
Details
   web
Records
Author (up) Sanna, M.; Acutis, M.; Bellocchi, G.
Title Interrelationship between evaluation metrics to assess agro-ecological models Type Report
Year 2014 Publication FACCE MACSUR Reports Abbreviated Journal
Volume 3 Issue Pages Sp3-5
Keywords
Abstract When evaluating the performances of simulation models, the perception of the quality of the outputs may depend on the statistics used to compare simulated and observed data. In order to have a comprehensive understanding of model performance, the use of a variety of metrics is generally advocated. However, since they may be correlated, the use of two or more metrics may convey the same information, leading to redundancy. This study intends to investigate the interrelationship between evaluation metrics, with the aim of identifying the most useful set of indicators, for assessing simulation performance. Our focus is on agro-ecological modelling. Twenty-three performance indicators were selected to compare simulated and observed data of four agronomic and meteorological variables: above-ground biomass, leaf area index, hourly air relative humidity and daily solar radiation. Indicators were calculated on large data sets, collected to effectively apply correlation analysis techniques. For each variable, the interrelationship between each pair of indicators was evaluated, by computing the Spearman’s rank correlation coefficient. A definition of “stable correlation” was proposed, based on the test of heterogeneity, allowing to assess whether two or more correlation coefficients are equal. An optimal subset of indicators was identified, striking a balance between number of indicators, amount of provided information and information redundancy. They are: Index of Agreement, Squared Bias, Root Mean Squared Relative Error, Pattern Index, Persistence Model Efficiency and Spearman’s Correlation Coefficient. The present study was carried out in the context of CropM-LiveM cross-cutting activities of MACSUR knowledge hub. No Label
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
Notes Approved no
Call Number MA @ admin @ Serial 2222
Permanent link to this record
 

 
Author (up) Sanz-Cobena, A.
Title Ammonia and nitrous oxide emissions from grazing cattle in Kenya Type
Year 2015 Publication FACCE MACSUR Reports Abbreviated Journal
Volume 5 Issue Pages Sp5-56
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 MACSUR Science Conference 2015 »Integrated Climate Risk Assessment in Agriculture & Food«, 8–9+10 April 2015, Reading, UK
Notes Approved no
Call Number MA @ admin @ Serial 2171
Permanent link to this record
 

 
Author (up) Savary, S.; Nelson, A.D.; Djurle, A.; Esker, P.; Sparks, A.; Amorim, L.; Bergamin Filho, A.; Caffi, T.; Castilla, N.; Garrett, K.; McRoberts, N.; Rossi, V.; Yuen, J.; Willocquet, L.
Title Concepts, approaches, and avenues for modelling crop health and crop losses Type Report
Year 2017 Publication FACCE MACSUR Reports Abbreviated Journal
Volume 10 Issue Pages C1.5-D
Keywords
Abstract Main text in preparation for publication in a peer-reviewed journal)
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
Notes CropM Approved no
Call Number MA @ admin @ Serial 4952
Permanent link to this record
 

 
Author (up) Schils, R.
Title Yield gaps of cereals across Europe Type Report
Year 2017 Publication FACCE MACSUR Reports Abbreviated Journal
Volume 10 Issue Pages Xc9.1-D1
Keywords
Abstract The increasing global demand for food requires a sustainable intensification of crop production in low-yielding areas. Actions to improve crop production in these regions call for accurate spatially explicit identification of yield gaps, i.e. the difference between potential or water-limited yield and actual yield. The Global Yield Gap Atlas (GYGA) project proposes a consistent bottom-up approach to estimate yield gaps. For each country, a climate zonation is overlaid with a crop area map. Within climate zones with important crop areas, weather stations are selected with at least 10 years of daily data. For each of the 3 dominant soil types within a 100 km zone around the weather stations, the potential and water-limited yields are simulated with the WOFOST crop model, using location-specific knowledge on crop systems. Data from variety trials or other experiments, approaching potential or water-limited yields, are used for validation and calibration of the model. Actual yields are taken from sub-national statistics. Yields and yield gaps are scaled up to climate zones and subsequently to countries. The average national simulated wheat yields under rainfed conditions varied from around 5 to 6 t/ha/year in the Mediterranean to nearly 12 t/ha/year on the British Isles and in the Low Countries. The average actual wheat yield varied from around 2 to 3 t/ha/year in the Mediterranean and some countries in East Europe to nearly 9 t/ha/year on the British Isles and in the Low Countries. The average relative yield gaps varied from around 10% to 30% in many countries in Northwest Europe to around 50% to 70% in some countries in the Mediterranean and East Europe. The paper will elaborate on results per climate zone and soil type, and will also include barley and maize. Furthermore we will relate yield gaps to nitrogen use.
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
Notes XC, CropM Approved no
Call Number MA @ admin @ Serial 4960
Permanent link to this record
 

 
Author (up) Schils, R.
Title Online maps of Yield Gaps of cereals across Europe Type Report
Year 2017 Publication FACCE MACSUR Reports Abbreviated Journal
Volume 10 Issue Pages Xc9.1-D2
Keywords
Abstract The yield gap and water productivity analysis of key cereal crops in Europe is completed  and results are available through www.yieldgap.org
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
Notes XC, CropM Approved no
Call Number MA @ admin @ Serial 4961
Permanent link to this record