References of "Tychon, Bernard"
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See detailRelationship between the progress of the foliar pathogens caused by Septoria tritici and the reduction of the photosynthetic vitality of plants in Grand-Duchy of Luxembourg in 2004.
El Jarroudi, Moussa ULg; Crumière, F.; Hausman, J.-F. et al

in Bibliotheca fragmenta agronomica - Book of proceedings (2006), 11(2), 643-644

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See detailGreen leaf area decline of wheat top three leaves in Belgium and G-D of Luxembourg from 2003 to 2005 : the relationships with grain yield.
Martin, B.; El Jarroudi, Moussa ULg; Tychon, Bernard ULg

in Bibliotheca fragmenta agronomica - Book of proceedings (2006), 11(1), 167-168

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See detailCrop yield forecast with NOAA and spot-vegetation data in Morocco.
Balaghi, Riad; Tychon, Bernard ULg; Eerens, H. et al

Conference (2006)

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See detailProtection and maintenance of permanent pastures
Gobin, B.; Brodsky, L.; Tychon, Bernard ULg et al

in Kay, Simon; Sima, Aleksandra; Loudjani, Philippe (Eds.) Proceedings of the 12th MARS PAC Annual Conference, 2006 (2006)

All farmers receiving direct payments are subject to compulsory cross-compliance which includes standards related to the maintenance and protection of permanent pastures. Questionnaire techniques and ... [more ▼]

All farmers receiving direct payments are subject to compulsory cross-compliance which includes standards related to the maintenance and protection of permanent pastures. Questionnaire techniques and spatio-temporal analyses demonstrated that the ratio of permanent pasture area to agricultural land provides a simple tool for monitoring and controlling the protection of permanent pastures at the regional to Member State level. Huge variations in the ratio across Europe were related to the importance of permanent pastures, the interpretation of definitions, sources of information used, differences in calculation, and the presence of protective and/or sensitive zones. Precautionary or complementary measures are in place in most Member States in order to prevent decreases in the ratio. The implementation of GAEC standards related to permanent pastures overlaps with the standard management requirements, national legislation and current agri-environmental programmes. The study advocates the establishment of a comprehensive geo-information platform consisting of a topologically correct inventory of all permanent pasture parcels in a 1:1 geo-referenced relation between IACS and LPIS; ancillary spatially explicit data such as orthophotos, remote sensing images and other thematic geo-databases; and, geodatabases with parcel information compiled for other monitoring purposes such as those within the framework of the Nitrates Directive or 2nd pillar support. [less ▲]

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See detailForecasting Septoria tritici on winter wheat in the Grand-Duchy of Luxembourg from 2000 to 2005.
El Jarroudi, Moussa ULg; Tychon, Bernard ULg; Maraite, H. et al

in Bibliotheca Fragmenta Agronomica - Book of Proceedings (2006), 11(2), 751-752

This papers presents the results of a wheat diseases model called PROCULTURE for the prediction of septoriosis in the Grand Duchy of Luxembourg

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See detailDetection of carbon stock change in agricultural soils using spectroscopic techniques
Stevens, Antoine; Van Wesemael, Bas; Vandenschrick, Grégoire et al

in Soil Science Society of America Journal (2006), 70(3, MAY-JUN), 844-850

Soil organic carbon (SOC) represents one of the major pools in the global C cycle. Therefore, even small changes in SOC stocks cause important CO, fluxes between terrestrial ecosystems and the atmosphere ... [more ▼]

Soil organic carbon (SOC) represents one of the major pools in the global C cycle. Therefore, even small changes in SOC stocks cause important CO, fluxes between terrestrial ecosystems and the atmosphere. However, SOC stocks are difficult to quantify accurately due to their high spatial variability. The aim of this paper is to evaluate the potential of Imaging Spectroscopy (IS) using the Compact Airborne Spectrographic Imager (CASI; 405-950 nm) and field spectroscopy with an Analytical Spectral Devices spectrometer (ASD; 350-2500 nm) to measure SOC content in heterogeneous agricultural soils. We used both stepwise and partial least square (PLS) regression analysis to relate spectral measurements to SOC contents. Standard Error of Prediction (SEP) for the ASD ranged from 2.4 to 3.3 g C kg(-1) depending on soil moisture content of the surface layer. Imaging spectroscopy performed poorly, mainly due to the narrow spectral range of the CASI. Tests using both the CASI and the Shortwave infrared Airborne Spectrographic Imager (SASI; 900-2500 nm) showed better results. The variation in soil texture and soil moisture content degrades the spectral response to SOC contents. Currently, SEP allows to detect a SOC stock change of 7.2-9.9 Mg C ha(-1) in the upper 30 cm of the soil, and is therefore still somewhat high in comparison with changes in SOC stocks as a result of management or land conversion (0.34.9 Mg C ha(-1) yr(-1)). A detailed SOC maps produced by IS reflected the patterns in SOC contents due to the recent conversion from grassland to cropland. [less ▲]

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See detailCGMS/WOFOST model principles
Tychon, Bernard ULg

Conference (2005, November)

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See detailBulletin agrométéorologique - Septembre 2005
Tychon, Bernard ULg; Ozer, Pierre ULg; De Longueville, Florence ULg et al

in Bulletin Agrométéorologique (2005), 4(5), 1-3

Le mois de septembre fut anormalement chaud et ensoleillé. Les précipitations furent par contre inférieures à la moyenne. A ce stade-ci de l’année, seules les prévisions relatives aux rendements du maïs ... [more ▼]

Le mois de septembre fut anormalement chaud et ensoleillé. Les précipitations furent par contre inférieures à la moyenne. A ce stade-ci de l’année, seules les prévisions relatives aux rendements du maïs fourrager et de la betterave sucrière sont calculées. Par rapport à l’année dernière et, sur l’ensemble du territoire, les prévisions de rendements de la betterave sucrière sont équivalentes, tandis que celles du maïs sont légèrement à la baisse. [less ▲]

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See detailBulletin agrométéorologique - Août 2005
Tychon, Bernard ULg; Ozer, Pierre ULg; De Longueville, Florence ULg et al

in Bulletin Agrométorologique (2005), 4(5), 1-4

Le mois d’août a été caractérisé par des valeurs climatiques proches de la normale. Cependant, les températures et les valeurs de rayonnement étaient anormalement faibles. Par rapport à l’année dernière ... [more ▼]

Le mois d’août a été caractérisé par des valeurs climatiques proches de la normale. Cependant, les températures et les valeurs de rayonnement étaient anormalement faibles. Par rapport à l’année dernière et, sur l’ensemble du territoire, les prévisions de rendements des principales cultures printanières sont équivalentes dans le cas de la betterave sucrière, et à la baisse pour le maïs fourrager et la pomme de terre Bintje. [less ▲]

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See detailBulletin agrométéorologique - Juillet 2005
Tychon, Bernard ULg; Ozer, Pierre ULg; De Longueville, Florence ULg et al

in Bulletin Agrométéorologique (2005), 4(4), 1-5

Le mois de juillet fut anormalement pluvieux en diverses régions du pays. Les autres paramètres climatiques furent néanmoins proches de la moyenne. Les prévisions de rendements des principales cultures ... [more ▼]

Le mois de juillet fut anormalement pluvieux en diverses régions du pays. Les autres paramètres climatiques furent néanmoins proches de la moyenne. Les prévisions de rendements des principales cultures sont globalement à la baisse sur le territoire par rapport à l’année dernière. [less ▲]

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See detailBulletin agrométéorologique - Juin 2005
Tychon, Bernard ULg; Ozer, Pierre ULg; De Longueville, Florence ULg et al

in Bulletin Agrométéorologique (2005), 4(3), 6

Tous les paramètres climatiques furent anormaux à exceptionnels par rapport à la moyenne durant le mois de juin. Aussi, les prévisions de rendements de principales cultures sont globalement à la baisse ... [more ▼]

Tous les paramètres climatiques furent anormaux à exceptionnels par rapport à la moyenne durant le mois de juin. Aussi, les prévisions de rendements de principales cultures sont globalement à la baisse sur le territoire. [less ▲]

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See detailBulletin agrométéorologique - mai 2005
Tychon, Bernard ULg; Ozer, Pierre ULg; Horion, S. et al

in Bulletin Agrométéorologique (2005), 4(2), 6

Si la situation météorologique est globalement normale en Belgique, dans certaines régions, le manque de précipitations cumulées depuis le début du printemps commence à inquiéter. A ce stade de l’année ... [more ▼]

Si la situation météorologique est globalement normale en Belgique, dans certaines régions, le manque de précipitations cumulées depuis le début du printemps commence à inquiéter. A ce stade de l’année culturale, les prévisions de rendements indiquent le maïs fourrager comme étant la culture la plus touchée par les conditions climatiques qui prévalent depuis plusieurs mois. Par contre, sur le plan national, par rapport à l’année passée, l’orge d’hiver et la pomme de terre Bintje marquent une certaine stabilité, tandis que le froment d’hiver et la betterave sucrière devraient voir leurs rendements légèrement augmenter. [less ▲]

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See detailBulletin agrométéorologique - Avril 2005
Tychon, Bernard ULg; Ozer, Pierre ULg; De Longueville, Florence ULg et al

in Bulletin Agrométéorologique (2005), 4(1), 1-5

L’hiver météorologique (décembre 2004 à février 2005) peut être caractérisé de normal, tout comme les mois de mars et avril qui lui ont succédé. La situation des cultures d’hiver est également normale ... [more ▼]

L’hiver météorologique (décembre 2004 à février 2005) peut être caractérisé de normal, tout comme les mois de mars et avril qui lui ont succédé. La situation des cultures d’hiver est également normale, avec des rendements qui s’annoncent généralement supérieurs à ceux de 2003 et de 2004 pour le froment d’hiver. Dans le cas de l’orge d’hiver, les estimations de rendements n’atteignent pas les résultats de 2004 mais dépassent largement les rendements observés en 2003. Il est prématuré d’émettre des prévisions pour les cultures printanières. [less ▲]

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See detailSuivi de l'état de l'AGRIculture WALlonne par TELédétection (projet SAGRIWATEL)
Tychon, Bernard ULg; Istasse, Alain

Conference (2005, May 11)

Le projet de recherche et développement sur le « Suivi de l’Etat l’Agriculture Wallonne par Télédétection (SAGRIWATEL) » entamé en janvier 2003 est réalisé dans le cadre d’une étroite collaboration entre ... [more ▼]

Le projet de recherche et développement sur le « Suivi de l’Etat l’Agriculture Wallonne par Télédétection (SAGRIWATEL) » entamé en janvier 2003 est réalisé dans le cadre d’une étroite collaboration entre une équipe de scientifiques provenant de différents organismes de recherche wallons (Centre Wallon de Recherches Agronomiques, Université de Liège, Université Catholique de Louvain, Faculté Universitaire des Sciences Agronomiques de Gembloux) et l’Administration Wallonne de l’Agriculture (DGA). Il vise à mettre en place pour l’Administration Wallonne de l’Agriculture des outils de suivi de l’agriculture tant pour ce qui concerne ses activités de production que pour ce qui concerne ses activités en lien avec la protection du milieu (mesures agro-environnementales). Ces outils sont conçus, selon les cas, pour du contrôle, de l’encadrement ou encore pour le suivi global de l’évolution de l’agriculture à l’échelle de la région wallonne. Le système vise à valoriser la base de données du Système Intégré de Gestion et de Contrôle (SIGC) qui est en mesure de fournir des informations pour des applications autres que celles pour lesquelles il a été conçu. En association avec de l’information satellite ou aérienne et des modèles de croissance des cultures une série d’applications concrètes ont été élaborées pour : - la prévision des productions agricoles - la délimitation de zones à stress hydrique - le repérage et l’estimation de surfaces ou de longueurs de bandes enherbées, haies,… - le repérage de la couverture hivernale des sols - le repérage du sens du labour - le suivi des successions culturales - le suivi de la diversité des cultures - l’évolution de la taille des parcelles - … Le système bénéficie de l’apport du SIGC graphique qui fonctionne en Belgique de manière opérationnelle depuis 1997. L’utilisation originale qui est faite du SIGC dans cette étude constitue une nouvelle valorisation de ce système cartographique au départ destiné uniquement à du contrôle des déclarations des agriculteurs. L’approche est intéressante car elle permet un meilleur suivi de l’état de l’agriculture pour l’Administration avec un outil dont elle a la maîtrise, lui permettant de répondre rapidement aux demandes, notamment de l’Europe. En outre, l’outil s’est révélé rapidement opérationnel et adaptable à de nouvelles demandes ce qui constitue un avantage non négligeable quand l’on analyse les fréquentes évolutions de la PAC de ces dernières années. Enfin, l’approche optimise les informations transmises par les agriculteurs lors de leur déclaration PAC, leur évitant des pertes de temps dans des demandes de renseignement répétitives conduisant en quelque sorte à une simplification administrative. L’accès à l’information au sein de la Direction Générale de l’Agriculture se fera via une interface WEB-GIS. Un prototype sera opérationnel dans moins de deux mois. Il est prévu qu’à terme, d’autres Institutions Wallonnes et les agriculteurs wallons euxmêmes puissent bénéficier de cette avancée technologique. [less ▲]

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See detailGeoTraceAgri final project report (GTA)
Debord, Michel; Chauchard, Alain; Tychon, Bernard ULg et al

Report (2005)

Are the universalisation and the globalisation of trade exchanges synonymous with a standardization in which agro-food products uprooted of their soil will no longer be differentiated from manufacturers ... [more ▼]

Are the universalisation and the globalisation of trade exchanges synonymous with a standardization in which agro-food products uprooted of their soil will no longer be differentiated from manufacturers or supermarket brands? Original food products belong to the inheritance of the territories and the consumers are attracted more and more by their authenticity. The GeoTraceAgri project resolutely supports agriculture and the sustainable promotion of the territory as opposed to universalisation which standardizes and moves away those who produce for consumers. Geotraceability aims at associating information of geographical nature with the traditional data of traceability. Farming origin and operations have become factual and verifi able data is available everywhere in the world, thus making it possible to bring additional guarantees to the signs of quality. The GeoTraceAgri (GTA) project largely contributed to the realisation of geotraceability. With the implementation from January 1,2005 of the new Common Agricultural Policy and its regulation imposing on the Member States a single system of declaration, all the agricultural parcels now form part of a European database of geographical references. This new regulation reinforces the basis of the concept of geotraceability, whereas throughout the project it was necessary to defi ne geo-indicators for integrated or crop production with very few geographical data on the farming precedents. The development of the GTA prototype rests on a decentralized architecture and Web services. It was indeed necessary to conceive a system which is readily accessible on Internet for farmers, co-operatives and collectors, and potentially with the administrations which have control responsibilities. In term of acceptability, the potential users realise the potential economic benefi ts of the concept and of the indicators of geotraceability in their plan of exploitation, on the other hand sociological acceptability is less evident which induces the need for communication to make for its adoption. This fi nal report fi nal illustrates the fi rst stage : the GeoTraceAgri partners are continuing their research on the defi nition of an integrated system of geotraceability for the Common agricultural policy and the plan of analysis of the results of GeoTraceAgri should lead to the marketing within two years of an application making it possible to integrate the geo-indicators into management software for the actors of the agro food chain. [less ▲]

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See detailMonitoring of the 2003 summer drought in Belgium with the NDWI applied on spot-vegetation data.
Horion, Stéphanie; Eerens, Herman; Tychon, Bernard ULg et al

in Veroustraete, F.; Bartholomé, E.; Verstraeten, W. W. (Eds.) Proceedings of the 2nd international vegetation user conference. 1998-2004 : 6 years of operational activities. (2005)

The summer 2003 was abnormally hot, sunny and dry. The average temperatures from June to August were the highest ever recorded in the Belgian reference meteorological station of Uccle, but also in other ... [more ▼]

The summer 2003 was abnormally hot, sunny and dry. The average temperatures from June to August were the highest ever recorded in the Belgian reference meteorological station of Uccle, but also in other countries of western and central Europe such as Portugal, Germany, Switzerland and the United Kingdom. Many human activities were affected by these particular climatic conditions, among which agriculture.The Normalized Difference Water Index (NDWI) applied on ten-daily SPOT- VEGETATION imagery is one of the drought indicators which could serve for the localisation of drought affected areas in Belgium. In this paper preliminary results show that detection of dry events is possible using historical averages of NDWI. Relative NDWI images can be used to monitor the development of the summer drought.These images are computed by the weighted difference between the NDWI values during this summer and its value at the same period in a reference year, which corresponds to a normal year in terms of rainfall availability. Analysis of the relation between NDWI and NDVI behaviours show that the green biomass influences the NDWI value especially during the growing season. More accurate study has to be done to individualize the specific NDWI behaviour during dry events. In perspectives, index validation with meteorological parameters and with the Relative Soil Moisture Index, which is an output of the Belgian Crop Growth Monitoring System, will improve this study. [less ▲]

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See detailUse of spot/vegetation in different versions of the European crop growth monitoring system.
Piccard, I.; Eerens, H.; Oger, Robert ULg et al

in Veroustraete, F.; Bartholomé, E.; Verstraeten, W. W. (Eds.) Proceedings of the 2nd international vegetation user conference, 1998-2004 : 6 years of operational activities (2005)

The Crop Growth Monitoring System (CGMS) is a GIS-application, developed and operated since 1989 by the MARS-unit of the EU Joint Research Centre. The primary objective is the timely forecasting of the ... [more ▼]

The Crop Growth Monitoring System (CGMS) is a GIS-application, developed and operated since 1989 by the MARS-unit of the EU Joint Research Centre. The primary objective is the timely forecasting of the yields of the main crops on the Pan-European continent.To reach this goal, CGMS combines all available (historical and actual) resources: official crop statistics, daily meteorological data, specific crop and soil parameters, the predictions of the (spatialized) crop growth model WOFOST, and the 10-daily composite images of NOAA-AVHRR and SPOT-VEGETATION. In recent years CGMS has been implemented in different regions of the world, also beyond Europe. This paper gives a brief overview of some of these applications, with emphasis on the remote sensing component, especially SPOT-VEGETATION. In 2000, JRC outsourced the practical operation of CGMS to a consortium composed by Alterra (main tasks, agrometeorological model), MeteoConsult (meteo-provider) and VITO (remote sensing). MARS-STAT delivers the European yield forecasts to the EU statistical office EUROSTAT, in view of the follow-up of market prices and the achievement of the CAP-regulations. MARS-FOOD particularly deals with important food producing areas (Russia, Mercosur) and famine-threatened zones in Africa (IGAD-zone). The long-term goal is to steadily fill the actual data gaps (crop areas, parameters, meteo,…) so that, in time, the full CGMS (incl. the model) could be applied on these areas (or even globally). Specific versions of CGMS emerged in different countries (Finland, Spain, Kazakhstan,…), running with more detailed input data. One example is the so-called B-CGMS which has been operating since 1998 on behalf of the Belgian ministry of agriculture, in a collaboration between ULg-Arlon, CRA-Gembloux and VITO. Since 2002, the B-CGMS group publishes monthly bulletins with forecasts on crop yields, areas and productions. The areas are delivered by the IACS (annually updated GIS of all crop parcels, maintained for the EU-CAP). Together with local partners, the same Belgian group is now implementing CGMS in China’s north-eastern province Heilongjiang, part of former Manchuria and China’s main producer of soybean, maize and singlecropped rice. Special attention is being paid to the steady drying-out of this region, which 50 years ago was mainly covered by wetlands and forests. Climate change and mismanaged paddy irrigation are leading to a dramatic lowering of the water tables. Technically, this paper will focus on the main deliverables derived from NOAA- AVHRR and SPOT- VEGETATION. This includes pre/post-processing, extraction of biophysical vegetation state parameters (NDVI, SAVI, fAPAR, Dry Matter Productivity), differences with regard to the historical year (VCI, VPI, etc.), quicklooks, etc. Of most concern however is the “ unmixing” approach, which attempts to conform the remote sensing data (image format, 1 km-pixels, different crops mixed) to the CGMS-standards (databases with district/crop as spatial/thematic units). If the low/medium resolution sensors (AVHRR, VEGETATION, MODIS, MERIS,..) want to maintain their role in this agricultural domain, this problem has to be solved. Otherwise, the floor is open for new, revolutionary initiatives such as DMC (Disaster Monitoring Constellation: daily global coverage at 32m resolution). [less ▲]

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See detailAnalyse climatique de la région de Gouré, Niger oriental : récentes modifications et impacts environnementaux
Ozer, Pierre ULg; Bodart, Catherine ULg; Tychon, Bernard ULg

in Cybergeo : Revue Européenne de Géographie = Cybergeo - European Journal of Geography (2005)

Since the late 1960s, the Sahel is affected by a dramatic drought. This article analyses climatic variations recorded in the Gouré area, eastern Niger, between 1936 and 2003. It appears that the drought ... [more ▼]

Since the late 1960s, the Sahel is affected by a dramatic drought. This article analyses climatic variations recorded in the Gouré area, eastern Niger, between 1936 and 2003. It appears that the drought ended in the late 1980s. However, the rainfall increase did not lead to an extension of the length of the rainy season. The study of the wind shows that correct data were recorded during the two first years of the station of Gouré (1984 and 1985). Afterwards, wind speed was entached by errors and did not report since 1997. The situation is alarming as we know that neighbouring stations meet the same problems and that no synoptic station currently reports wind values in eastern Niger. However, based on wind speed and deflation data recorded in 1984, a threshold wind speed of 7 m/s was determined in Gouré. Finally, from measurements of horizontal visibility reduced by mineral dust, our results suggest that air quality is reduced because of the high frequency of wind erosion. The confrontation of our results with recent environmental studies in that region show that the end of the drought did not lead to any landscape improvement. Increasing human pressure tends to be the main driving factor of land degradation. [less ▲]

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See detailCan hyperspectral techniques improve estimates of carbon stocks in agricultural soils ?
Stevens, A.; van Wesemael, B.; Touré, Souleymane et al

in Proceedings of the Airborne imaging spectroscopy workshop : Belspo, Bruges 8 octobre 2004 (2004, October 08)

Soil organic carbon (SOC) represents one of the major pools in the global carbon cycle. However, fluxes of CO2 from soils into the atmosphere by respiration or inversely sequestration of CO2 through ... [more ▼]

Soil organic carbon (SOC) represents one of the major pools in the global carbon cycle. However, fluxes of CO2 from soils into the atmosphere by respiration or inversely sequestration of CO2 through photosynthesis and subsequent immobilisation in the form of humus are difficult to quantify. In principle changes in SOC stock over time reflect CO2 fluxes. The detection of these stock changes, however, require intensive sampling mainly due to the large spatial variability of SOC both within individual fields and larger units with similar soils and land use. The aim of this paper is to evaluate the potential of airborne-hyperspectral techniques using a CASI sensor and hand held Near Infrared Spectroscopy (NIRS) with an ASD spectrometer to conduct SOC inventories of individual parcels. During a field campaign in the Belgian Ardennes during Octobre 2003, more than 120 sites on a regular grid within 13 freshly ploughed fields were selected. At these sites, field spectra of the bare soil have been measured and samples from the topsoil were taken. SOC content (Walkley and Black), soil moisture and bulk density of these samples have been determined. As a first step, the soil reflectance has been transformed (log (1/R), Savitsky-Golay smoothing and derivative, gap derivative, moving average) in order to filter the spectral responses and to eliminate noise. Then, we used both stepwise and partial least square (PLS) regression analysis to relate these spectra to measured SOC contents. Regression models performed much better when the data were divided in two sub-groups representing different moisture conditions of the soil surface. These statistical model calibrations were validated on an independent data set. Standard Error of Prediction (SEP) ranged from 0.19 to 0.24 % carbon for the field spectra determined using the ASD depending on soil moisture of the surface layer. This is a little bit more than the reproducibility error inherent to the Walkley and Black analysis. Airborne CASI techniques performed less well mainly due to the narrow spectral range. Tests on airborne CASI+SASI hyperspectral data from a previous field campaign [1] showed better results. Overall, low bias allowed the use of spectral techniques to estimate population means with a high confidence level. The spectral techniques have a strong potential in determining changes in carbon tock change studies. The large within field variability of SOC content precludes the assessment, using conventional soil sampling, of SOC changes as a result of management (1 t C ha-1 yr-1) over a reasonable time period (5 years). Depending on the variance of the SOC content measured in the field ( 2 = 11-166 t C ha-1), we need 16-210 samples to detect a change. Since this number of samples is rarely available for individual fields, conventional sampling methods can only be used for larger spatial units containing many fields. In contrast, the airborne-hyperspectral technique and portable NIRS are able to supply these large amounts of data, and can thus improve the accuracy of SOC stock assessments of individual fields. This in turn will result in a smaller detection limit of SOC stock changes. [less ▲]

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