Papers by Gianni Bellocchi
European Journal of Agronomy, 2003
The software irene (Integrated Resources for Evaluating Numerical Estimates) is a data analysis t... more The software irene (Integrated Resources for Evaluating Numerical Estimates) is a data analysis tool designed to provide easy access to statistical techniques for use in model evaluation. Mostly, non-replicated model estimates (Ei) are compared against non-replicated measurements (Mi). The software also allows comparing individual estimates against replicated measurements (or vice versa) and replicated estimates against replicated measurements. The evaluation of
European Journal of Agronomy, 2003
The software IRENE (Integrated Resources for Evaluating Numerical Estimates) is a data analysis t... more The software IRENE (Integrated Resources for Evaluating Numerical Estimates) is a data analysis tool designed to provide easy access to statistical techniques for use in model evaluation. Mostly, non-replicated model estimates (E i ) are compared against non-replicated measurements (M i ). The software also allows comparing individual estimates against replicated measurements (or vice versa) and replicated estimates against replicated measurements. The evaluation of model performance is essentially based on the difference E i (/M i , or on the correlation Á/regression of E i vs. M i (or vice versa). In addition, model evaluation by probability distributions, pattern analysis, or fuzzy-based aggregation statistics is allowed. Graphics are included in most analytical tasks. The results are displayed in separate spreadsheets and can be exported into MS Excel workbooks. #
Page 2 of 123 SEAMLESS integrated project aims at developing an integrated framework that allows ... more Page 2 of 123 SEAMLESS integrated project aims at developing an integrated framework that allows exante assessment of agricultural and environmental policies and technological innovations. The framework will have multi-scale capabilities ranging from field and farm to the EU25 and globe; it will be generic, modular and open and using state-of-the art software. The project is carried out by a consortium of 30 partners, led by Wageningen University (NL).
BACKGROUND. Simulation models are increasingly be- ing used for describing and predicting soil-cr... more BACKGROUND. Simulation models are increasingly be- ing used for describing and predicting soil-crop vari- ables under a wide variety of conditions for provid- ing guidelines at farming level. The CropSyst model was regarded as a valuable tool for investigating con- tinuous maize, relating to crop production and the environment. METHODS. The CropSyst model was evaluated for its ability to simulate
One of the largest consequences of projected climate change is an increased frequency of extreme ... more One of the largest consequences of projected climate change is an increased frequency of extreme weather events or conditions. They impact heavily on crops as they are out of the range of variability which crops are adapted to. As an example, air temperature is a driving variable involved in the simulation of plant development, and it is used for estimating
Geomorphology, 2015
In European catchments, rainfall and overland flow trigger erosive processes that could result in... more In European catchments, rainfall and overland flow trigger erosive processes that could result in soil detachment and transportation. However, estimation of both erosive rainfalls and sediment yields is very challenging, especially in historical times when only precipitations at seasonal or annual scales are available. This motivated us to develop a parsimonious hydroclimatological model (ASCLIM, Annual Sediment CLImatological Model) for predicting catchment scale sediment yield when temporal and spatial high-resolution precipitation data are not available. The model was developed by using the annual data of suspended-sediment yield from Glonn basin (1981-1995, gauge of Hohenkammer, Germany) and seasonal rainfall data from a NOAA data set. The correlation coefficient between predicted and observed sediment yields was 0.94 and the efficiency index was 0.89. Once parameterized, the model was able to capture annual sediment yield variability better than the Langbein-Schumm and the Fournier Index equations, also based on limited sets of inputs. The model holds potential for historical reconstruction of sediment yields in the Glonn catchment (assuming constant land cover) and for simulating sediment fluxes from catchments with similar characteristics. Our application highlights the control of rainfall seasonality on sediment export and demonstrates that our sediment yield proxy could be considered as a good tool for the expectation and planning of soil conservation. Moreover, considering that we used modeled data to reconstruct past sediment loss, we could expect that using projected future rainfall data our proxy could be able to assess future scenarios.
Environmental and Agricultural Modeling:, 2009
Several simulation tools allow the impact of agricultural management on production activities in ... more Several simulation tools allow the impact of agricultural management on production activities in specific environments to be studied (eg Brisson et al. 2003; Keating et al. 2003; Jones et al. 2003; Stockle et al. 2003; Van Ittersum et al. 2003). Such tools are specialized, to ...
Spin-up runs usually used to initialize mechanistic biogeochemical models highly increase the tim... more Spin-up runs usually used to initialize mechanistic biogeochemical models highly increase the time required to make simulations. The aim of this paper is to evaluate the use of linear and quadratic regression models, as an alternative way to initialize such models. This option is illustrated with the grassland ecosystem Pasture Simulation model (PaSim) under a range of climate, soil and
Vulnerability is the degree to which human and environmental systems are likely to experience har... more Vulnerability is the degree to which human and environmental systems are likely to experience harm due to a perturbation or a stress. In the last years, it has become a central focus of the global change (including climate change). The climate change literature contains many explanations of vulnerability, stemming from the notion of sensitivity to more complex ideas, yet taking
Theoretical and Applied Climatology, 2012
The paper reports the results of the analysis of the 14 longest precipitation instrumental series... more The paper reports the results of the analysis of the 14 longest precipitation instrumental series, covering the last 300 years, that have been recovered in six subareas of the Western Mediterranean basin, i.e., Portugal, Northern and Southern Spain, Southern France, Northern and Southern Italy. This study extends back by one century our knowledge about the instrumental precipitation over the Western Mediterranean, and by two centuries in some specific subareas. All the time series show repeated swings. No specific trends have
Theoretical and Applied Climatology, 2013
This work presents the reconstruction of a time series of annual winter air temperatures across C... more This work presents the reconstruction of a time series of annual winter air temperatures across Central and Southern Italy for the period 1500-2010 that largely overlaps the Little Ice Age (LIA) period (1300-1850). A detailed analysis was undertaken on winter mean temperature data using both observations (1871-2010) and proxy-based reconstructions (1500-1870). Based on this homogeneized reconstructed series, a time-dependency in low-frequency time-pattern of temperatures (70-and 130-year cycles) was suggested although the temporal oscillation was not merely periodic. The LIA was characterized by marked climatic variability over this part of Southern Europe, with particular emphasis during the so-called "Maunder Minimum" (MM), between 1645 and 1715. The interannual variability of low temperatures, in particular, makes the MM an outstanding climatic period. There is some consistency that patterns of warming conditions observed in recent times also occurred in the past. Quasiperiodic cycles appear as a consequence of stochastic resonance emerging in long time scales but the variability inherent to the series of winter temperatures, although likely generated by processes internal to the climate system, is difficult to forecast because the system is chaotic and affected by unpredictable noise.
Water Resources Management, 2010
The study presents a geospatial knowledge transfer framework by accommodating precipitation maps ... more The study presents a geospatial knowledge transfer framework by accommodating precipitation maps for the Eastern Nepalese Highland (ENH) across an area of about 100,000 km 2 . For this remote area, precipitation-elevation relationships are not homogeneously distributed, but present a chaotic gradient of correlations at altitude ranges. This is mainly due to impervious orography, extreme climate, and data scarcity (most of the rain gauges in Himalaya are located at valley bottoms). Applying geostatistical models (e.g. multivariate geospatial approaches) is difficult in these zones. This makes the ENH an interesting test area where we obtained monthly precipitation spatial patterns for a 30-year period . The aim was to both capture orographic meso-α spatial regimen (∼30 km) and local pattern variability (∼10 km). Data from 58 FAO raingauges were used plus data from an atmospheric weather station (AWS Pyramid) operating at 5,050 m a.s.l., used to compensate the gap of precipitation pattern presents in the area surrounding the Mount Everest. In these complex orographically remote areas of the Himalayas, monsoon precipitation systems exhibit important topographical interactions and spatial correlations, depending on the scale at which the primary variable (e.g., precipitation) and co-variables (e.g., elevation) are recorded and analysed. Precipitations were assessed for months-May, July and September-representative N. Diodato (B) · G. Bellocchi of precipitation values from ∼100 mm over the Tibetan Plateau to ∼500 mm in the southern part of Nepal, up to ∼900 mm towards the pre-Himalayan range. For July, cokriging precipitation map also showed correspondence with the map of vegetation pattern, and therein lies the clue to using multivariate geostatistical models as flexible approaches for estimating precipitation spatial patterns in remote areas.
Transgenic Research, 2010
This paper illustrates the advantages that a fuzzy-based aggregation method could bring into the ... more This paper illustrates the advantages that a fuzzy-based aggregation method could bring into the validation of a multiplex method for GMO detection (DualChip Ò GMO kit, Eppendorf). Guidelines for validation of chemical, bio-chemical, pharmaceutical and genetic methods have been developed and ad hoc validation statistics are available and routinely used, for in-house and inter-laboratory testing, and decision-making. Fuzzy logic allows summarising the information obtained by independent validation statistics into one synthetic indicator of overall method performance. The microarray technology, introduced for simultaneous identification of multiple GMOs, poses specific validation issues (patterns of performance for a variety of GMOs at different concentrations). A fuzzy-based indicator for overall evaluation is illustrated in this paper, and applied to validation data for different genetically modified elements. Remarks were drawn on the analytical results. The fuzzy-logic based rules were shown to be applicable to improve interpretation of results and facilitate overall evaluation of the multiplex method.
Theoretical and Applied Climatology, 2009
A crop simulation model must first be capable of representing the actual performance of crops gro... more A crop simulation model must first be capable of representing the actual performance of crops grown in any region before it can be applied to the prediction of climate variability and change impacts. A cropping systems model (CropSyst) simulations of crop productivity in the sub-Saharan Central African (using Cameroon as the case study) region, under the current climate were compared with observed yields of maize, sorghum, groundnut, bambara groundnut and soybean from eight sites. The model produced both over-and-under estimates, but with a mean percentage difference of only -2.8%, ranging from -0.6% to -4.5%. Based on these results, we judged the CropSyst simulations sufficiently reliable to justify use of the model in assessing crop growth vulnerability to climatic changes in Cameroon and else where.
… Congress on Modelling …, 2005
Investigating the potential impact of climate on agro-ecosystems using simulation models is under... more Investigating the potential impact of climate on agro-ecosystems using simulation models is underpinned by the availability of climate data at the appropriate temporal scale (daily or higher resolution). The production of artificial series of weather data has traditionally adopted a variety of alternative methods. These range from empirical functions where simple relationships between weather variables are used to estimate missing data from available data, to sophisticated approaches where physically-based models are used. All such approaches illustrate from different perspectives that there is actually a wealth of well developed solutions to the basic problem of estimating or generating weather data, coded in a variety of ways. The weather generation and estimation problem and the frequent need to evaluate alternative approaches in a comparative fashion has suggested that these methods be made available as one, comprehensive set of linkable components which also allow for extension by third parties of models that have already been implemented.
Industrial Crops and Products, 2012
The optimal combination of yield and quality of hemp fibres from field grown crops is around flow... more The optimal combination of yield and quality of hemp fibres from field grown crops is around flowering. Therefore prediction of flowering time would support in planning production and optimization of the cultivar choice for different agro-ecological zones. In the current paper the validation of a recently published model is carried out for four varieties across a wide range of sites and thus of air temperature-photoperiod combinations. The model was evaluated by comparing its output to field observations of the duration between emergence and 50% flowering. The model output and observed times from emergence to 50% of flowering generally corresponded well, but some discrepancies were apparent. The biggest discrepancies between estimates and actual data were observed at extreme latitudes. The level of accuracy of the model predictions is satisfactory for strategic decision regarding sowing and harvesting time and cultivar choice, but tactical decisions (e.g. time of harvest based on flowering time) cannot be accurately supported.
Food Analytical Methods, 2011
The first successful application of the ELISA reverse method and device (ER m&amp... more The first successful application of the ELISA reverse method and device (ER m&d), in the context of food safety and traceability, was developed in our laboratories to detect and quantify CP4EPSPS and Cry1AB genetically modified related proteins in soy and maize samples, respectively. To prove the versatility and the transferability of the technology, the ER was here applied to assess
European Journal of Agronomy, 2006
Evapotranspiration (ET) is a cross-platform software component containing routines to estimate da... more Evapotranspiration (ET) is a cross-platform software component containing routines to estimate daily and hourly values of reference evapotranspiration (and related variables) according to alternative approaches. A standardized form of the FAO-56 implementation of the Penman-Monteith equation is used to estimate daily and hourly evapotranspiration for two reference surfaces (namely clipped grass and alfalfa). Other methods (implementations of Priestley-Taylor and Hargreaves equations) estimate daily evapotranspiration from limited sets of inputs. A multi-layer canopy, similar to a well-developed tomato crop within standard greenhouse conditions, is taken as a reference to estimate hourly evapotranspiration in greenhouse environment (Stanghellini approach). The component is released as .NET (C#) version, allowing the development of clients under Windows operating systems. The component has an extensive hypertext help file. The component design allows users developing client applications to extend the functionalities by adding further options for estimating reference ET. Illustrative examples of clients developed in C# are provided as source code; the component is made available as compiled version. Also, the component was used to activate a web service and a web application based on such a service; the relevant C# code is provided as example.
Food Analytical Methods, 2008
Validation is the process establishing the suitability of an analytical method for a particular p... more Validation is the process establishing the suitability of an analytical method for a particular purpose. Various guidelines defining statistical procedures for validation of chemical, bio-chemical, pharmaceutical, and molecular methods have been developed, and ad hoc validation metrics (indices and test statistics) are available and routinely used, for in-house and interlaboratory testing and decision making. However, there is no universally accepted practice for assay validation, and often, subjectivity plays an important role in the interpretation of validation studies' results. Instead, the key to rational validation studies relies upon the formalization and harmonization of procedures for their design and interpretation of results. Fuzzy-based techniques can be helpful in such respect. Fuzzy logic allows summarizing the information obtained by classic independent validation statistics into one synthetic index of overall method performance. The possibility of having a comprehensive indicator of method performance has the advantage of permitting direct method comparison, facilitating the evaluation of many individual, possibly contradictory metrics. The objectives of this paper are to illustrate the advantages that a fuzzy-based aggregation method could bring into the validation of analytical methods and to propose its application for the evaluation of methods' performance. Validation metrics are compared for practical examples of assessment of method performance in collaborative studies. Fuzzy logic-based rules are shown to be applicable to improve insights into method quality and interpretation of results.
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Papers by Gianni Bellocchi