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See detailMonitoring of statospheric changes at the Jungfraujoch station by high-resolution infrared solar observations in support of the Network for Detection of Stratospheric Change (NDSC)
Zander, Rodolphe ULg; Mahieu, Emmanuel ULg; Demoulin, Philippe ULg

in Chanin, M.-L. (Ed.) The role of the stratosphere in global change (1993)

Infrared remote sensing observations from the ground, using the sun as source of radiation, constitute a powerful tool for monitoring the state of our environment. The observational effort carried out at ... [more ▼]

Infrared remote sensing observations from the ground, using the sun as source of radiation, constitute a powerful tool for monitoring the state of our environment. The observational effort carried out at the International Scientific Station of the Jungfraujoch, Switzerland, is used in this paper as a typical example to stress out the performances achievable by that technique. When based on high spectral resolution and high signal-to-noise observations, it can overcome the bulk of the absorption produced by gases with high concentration in the troposphere and contribute efficiently to the quantification and monitoring of trace gases predominantly concentrated in the stratosphere. [less ▲]

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See detailMonitoring of surface interactions as a tool for nanoparticle design
Frost, R; Grandfils, Christian ULg; Kasemo, B et al

Poster (2010, April 07)

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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 detailMonitoring of the atmospheric burdens of CH4, N2O, CO, CHCIF2 and CF2Cl2 above Central Europe during the last decade
Zander, Rodolphe ULg; Demoulin, Philippe ULg; Mahieu, Emmanuel ULg

in Environmental Monitoring & Assessment (1994, May), 31(1-2), 203-209

Based on high spectral resolution infrared solar observations made at the International Scientific Station of the Jungfraujoch, Switzerland, total vertical column abundances of 18 atmospheric gases have ... [more ▼]

Based on high spectral resolution infrared solar observations made at the International Scientific Station of the Jungfraujoch, Switzerland, total vertical column abundances of 18 atmospheric gases have been monitored routinely since 1984. The observed temporal evolutions in the columns of CH4, N2O, CO, CHClF2 (HCFC-22) and CF2Cl2 (CFC-12) are reported here as typical examples of this monitoring effort which is conducted within the frame of ''Global Change'' and ''Network for the Detection of Stratospheric Change'' programs. [less ▲]

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See detailMonitoring of the crop water stress in Belgium. The case of the 2003 heat wave.
Horion, Stephanie; Tychon, Bernard ULg; De Longueville, Florence ULg

Conference (2006, October)

In this paper the crop water stress is evaluated with three different indices: (i) the Relative Soil Moisture Index [RSMI] resulting from agrometeorological model simulations, (ii) the Normalized ... [more ▼]

In this paper the crop water stress is evaluated with three different indices: (i) the Relative Soil Moisture Index [RSMI] resulting from agrometeorological model simulations, (ii) the Normalized Difference Vegetation Index, [NDVI] applied on S10 SPOT-VGT imagery, (iii) the Normalized Difference Water Index, [NDWI] applied on S10 SPOT-VGT imagery. [less ▲]

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See detailMonitoring of the crop water stress in Belgium. The case of the 2003 heat wave.
Horion, Stéphanie; Tychon, Bernard ULg; De Longueville, Florence ULg

Conference (2006, October)

In this paper the crop water stress is evaluated with three different indices: (i) the Relative Soil Moisture Index [RSMI] resulting from agrometeorological model simulations, (ii) the Normalized ... [more ▼]

In this paper the crop water stress is evaluated with three different indices: (i) the Relative Soil Moisture Index [RSMI] resulting from agrometeorological model simulations, (ii) the Normalized Difference Vegetation Index, [NDVI] applied on S10 SPOT-VGT imagery, (iii) the Normalized Difference Water Index, [NDWI] applied on S10 SPOT-VGT imagery. The RSMI is one of the outputs of the Belgian Crop Growth Monitoring System. It indicates the soil water availability for crops. Crop water stress is assumed when soil water availability is lower than the crop potential evapotranspiration. One of the potential applications for drought monitoring is the calculation of the number of days with a crop water stress during the growing season or more precisely during the “moisture-sensitive period” of the crop. The two others (well-known) indices are derived from low resolution satellite imagery. Complete time series of S10 SPOT-VGT NDVI and NDWI data - i.e. from April 1998 onwards – have been acquired for the research. Using spatial information on land-uses in Belgium, a simple unmixing method is implemented to partly reduce the problem of mixed values occurring inevitably in 1x1km² pixels. Only the most agricultural pixels are considered for the analysis. The heat wave occurred during the summer 2003 has been chosen as a study case for the comparison. This summer was particularly hot, dry and sunny with the highest averaged temperature ever recorded from June to August in Uccle-Belgium. Many human activities were affected by this particular climatic condition, among which agriculture. In order to make the comparison possible, a standardization of the outputs of the 3 indexes is realised, taking into account the times series of each indexes. Moreover all the outputs are aggregated at municipality level. [less ▲]

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See detailMonitoring of the de-esterification and depolymerisation of pectins by nirs.
Sinnaeve, G.; Ciza, A.; Deconinck, T. et al

Poster (2003, May 09)

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See detailMonitoring of the dynamics of the natural resources by the geomatic in Morocco
Mahyou, Hamid ULg; Tychon, Bernard ULg

Scientific conference (2008, January 29)

Drylands cover about 40 % of Earth’s land surface and are inhabited by more than 2 billion people who depend mainly on the exploitation of these dryland ecosystem natural resources. However, it is largely ... [more ▼]

Drylands cover about 40 % of Earth’s land surface and are inhabited by more than 2 billion people who depend mainly on the exploitation of these dryland ecosystem natural resources. However, it is largely recognized that these areas are threatened by the desertification. Desertification is associated with biodiversity loss and contrib-utes to global climate change. In spite of the importance of this phenomenon, it is surprising that there is no consensus on an appropriate method to assess this degradation process. One part of the literature announces catastrophic statistics on the rate of desert extension and surface affected. Others, doubt about the methodology used by these first studies and do not find any obviousness of such an extent of desertification. The overall goal of our study is to develop remote sensing based indicators and models for the assessment of desertification in drylands. For this purpose, the monitoring of vegetation and soil is based on information resulting from the remote sensing and the biophysics data. Hyperspectral (field and remote sensing) and biophysics parameters will be established for the study area through large field campaigns combined with HR-remote sensing data. The Land Cover will be mapped using the Landsat TM images in conjunction with measurements of vegetation parameters such as biomass and vegetation cover. Hyperspectral reflectances of the vegetation and soil inside the study zone will be measured by a Spectroradiometer. Each site will be located by Global Positioning System (GPS). Several RS vegetations indices appropriate for rangeland will be studied and others will be developed. Regression analyses, between the different vegetation indices retained by remote sensing and the biophysics data will be carried out so as to establish a spatio-temporal model linking these indices to the vegetation parameters. This research has started in November 2007 [less ▲]

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See detailMONITORING OF THE ENTOMOLOGICAL DIVERSITY IN A PESTICIDE FREE ORCHARD: INVESTIGATION OF THE GEMBLOUX AGRICULTURAL UNIVERSITY CONSERVATORY
Poligui, René Noël ULg; Haubruge, Eric ULg; Francis, Frédéric ULg

Poster (2009, May 19)

In orchards, the fruit production is currently oriented to integrated pest management. In order to develop efficient pest control strategy by using entomophagous beneficial and lowering the application of ... [more ▼]

In orchards, the fruit production is currently oriented to integrated pest management. In order to develop efficient pest control strategy by using entomophagous beneficial and lowering the application of pesticides, sufficient knowledge of entomological populations is needed. Here, a systematic monitoring of insect diversity and abundance in a conservatory orchard of Gembloux was performed. Combining yellow traps and visual observations, 19 pest and 34 beneficial families were identified among the 10766 and 3985 insects caught in yellow traps and visual observations respectively. Calculation of diversity indices allowed us to demonstrate the variability according to fruit tree species and insects observation method. Highest insects diversity was registered in apple, then in cherry and finally in the apple-pear association and plum. Pests and beneficials represented 27% and 39% of the insect collections respectively. Aphids represented from 81% to 95%of pests depending on fruit tree species and observation method. The predominant specie was Brachycaudus helychrysi (Kaltenbach). Aphidophagous guild was largely present and mainly constituted by coccinellids and hoverflies. Harmonia axyridis Pallas and Episyrphus balteatus De Geer were the most abundant. Aphididae was found to be the most common orchard pests with a range of related aphidophagous beneficials. These results highlight the need leading to potential reasoning . [less ▲]

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See detailMonitoring of the entomological diversity in a pesticide free orchard:Investigation in the Gembloux agricultural University conservatory
Poligui, René Noël ULg; Haubruge, Eric ULg; Francis, Frédéric ULg

in Communication in Agricultural and Applied Biological Sciences Ghent University (2010), 74/2

In orchards, the fruit production is currently oriented to integrated pest management. In order to develop efficient pest control strategy by using entomophagous beneficial and lowering the application of ... [more ▼]

In orchards, the fruit production is currently oriented to integrated pest management. In order to develop efficient pest control strategy by using entomophagous beneficial and lowering the application of pesticides, sufficient knowledge of entomological populations is needed. Here, a systematic monitoring of insect diversity and abundance in a conservatory orchard of Gembloux was performed. Combining yellow traps and visual observations, 19 pest and 34 beneficial families were identified among the 10766 and 3985 insects caught in yellow traps and visual observations respectively. Calculation of diversity indices allowed us to demonstrate the variability according to fruit tree species and insects observation method. Highest insects diversity was registered in apple, then in cherry and finally in the apple-pear association and plum. Pests and beneficials represented 27% and 39% of the insect collections respectively. Aphids represented from 81% to 95%of pests depending on fruit tree species and observation method. The predominant specie was Brachycaudus helychrysi (Kaltenbach). Aphidophagous guild was largely present and mainly constituted by coccinellids and hoverflies. Harmonia axyridis Pallas and Episyrphus balteatus De Geer were the most abundant. Aphididae was found to be the most common orchard pests with a range of related aphidophagous beneficials. These results highlight the need leading to potential reasoning. [less ▲]

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See detailThe monitoring of the enzymatic depolymerisation of pectins by spectroscopic techniques.
Sinnaeve, G.; Ciza, A.; Deconinck, T. et al

Poster (1999, July)

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See detailMonitoring of the integrated column of hydrogen fluoride above the Jungfraujoch Station since 1977 — the HF/HCl column ratio
Zander, Rodolphe ULg; Roland, G.; Delbouille, L. et al

in Journal of Atmospheric Chemistry (1987), 5(4), 385-394

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See detailMonitoring of the intra-dermal tuberculosis skin test performed by Belgian field practitioners
Humblet, Marie-France ULg; Walravens, K.; Salandre, O. et al

in Research in Veterinary Science (2011)

The present study aimed to monitor skin test practices as performed by veterinarian field practitioners in Belgium. For this purpose, an anonymous postal questionnaire was elaborated and dispatched to ... [more ▼]

The present study aimed to monitor skin test practices as performed by veterinarian field practitioners in Belgium. For this purpose, an anonymous postal questionnaire was elaborated and dispatched to veterinarians involved in bovine tuberculosis detection. The questionnaire included items focusing on the skin test performance. International experts in the field of bovine tuberculosis were asked to fill the questionnaire and a scoring scale was built as follows: 0='ideal' answer, 1=acceptable answer, whereas 2=unacceptable answer. Furthermore, experts were asked to rank the questionnaire's items according to their possible impact on the risk of not detecting reactors. A global score was further calculated for each participant and a comparison of practices was carried out between the two regions of the country, i.e. Wallonia and Flanders. Significant differences were observed between both regions, a harmonization at the country level is thus essential. No veterinarian summed a null score, corresponding to the ideal skin test procedure, which suggests that skin-testing is far from being performed correctly. Field practitioners need to be sensitized to the importance of correctly performing the test. The authors recommend the questionnaire is suitable for application in other countries or regions [less ▲]

Detailed reference viewed: 31 (6 ULg)
See detailThe monitoring of the ionospheric activity using GPS measurements
Warnant, René ULg; Stankov, Stanimir; Jodogne, Jean-Claude et al

in Proceedings of the COST271 2002 workshop (2003)

Detailed reference viewed: 11 (0 ULg)
See detailMonitoring of the variability and long-term evolution of tropospheric constituents by Infrared solar absorption spectrometry at the Jungfraujoch, Switzerland.
Zander, Rodolphe ULg; Mahieu, Emmanuel ULg; Duchatelet, Pierre ULg et al

in Borrell, P.; Borrell, P. M.; Burrows, J. P. (Eds.) et al Sounding the Troposphere from Space: A new era for Atmospheric Chemistry. (2003)

Detailed reference viewed: 6 (1 ULg)
Peer Reviewed
See detailMonitoring of triclabendazole efficacy in naturally infected cattle using an antigen competition ELISA
Leclipteux, T.; Bossaert, K.; Protz, M. et al

Poster (1997)

Detailed reference viewed: 5 (0 ULg)