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Disturbance, management, and landscape dynamics: harmonic regression of Vegetation Indices in the Lower Okavango Delta, Botswana / A.L. Neunschwander in Photogrammetric Engineering & Remote Sensing, PERS, vol 74 n° 6 (June 2008)
[article]
Titre : Disturbance, management, and landscape dynamics: harmonic regression of Vegetation Indices in the Lower Okavango Delta, Botswana Type de document : Article/Communication Auteurs : A.L. Neunschwander, Auteur ; K.A. Crews, Auteur Année de publication : 2008 Article en page(s) : pp 753 - 764 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse diachronique
[Termes IGN] analyse harmonique
[Termes IGN] Botswana
[Termes IGN] delta
[Termes IGN] image Landsat-ETM+
[Termes IGN] image Landsat-TM
[Termes IGN] indice de végétation
[Termes IGN] plan d'occupation du sol
[Termes IGN] régression
[Termes IGN] série temporelle
[Termes IGN] surface cultivée
[Termes IGN] traitement du signalRésumé : (Auteur) Focused on the Okavango Delta, Botswana, this research investigates (a) whether ecosystem signals derived from remotely sensed imagery can be decomposed using a harmonic regression, (b) if the deviations from the decomposed signal are correlated with observed flooding and fire regimes, and (c) the impact of explicitly including agriculture, settlement areas, and land management systems on the derived signals. A time-series of 85 TM/ETM+ scenes spanning the period from 1989 through 2002 was used to decompose derived landscape dynamics into trends, annual and seasonal cycles, and long term oscillations. The harmonic fit largely defined by climatic periodicities (semi-annual, annual, and quasi-decadal) accounted for 63 percent to 88 percent of the variance in the trajectories. The trends were found to be robust whether or not urban settlement or landscape management regimes were explicitly included, though there was a reversal of trend in agricultural areas. Copyright ASPRS Numéro de notice : A2008-200 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.74.6.753 En ligne : https://doi.org/10.14358/PERS.74.6.753 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29195
in Photogrammetric Engineering & Remote Sensing, PERS > vol 74 n° 6 (June 2008) . - pp 753 - 764[article]Assimilation of SPOT-Vegetation NDVI data into a Sahelian vegetation dynamics model / Lionel Jarlan in Remote sensing of environment, vol 112 n° 4 (15/04/2008)
[article]
Titre : Assimilation of SPOT-Vegetation NDVI data into a Sahelian vegetation dynamics model Type de document : Article/Communication Auteurs : Lionel Jarlan, Auteur ; S. Mangiarotti, Auteur ; et al., Auteur Année de publication : 2008 Article en page(s) : pp 1381 - 1394 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] flore locale
[Termes IGN] image SPOT-Végétation
[Termes IGN] intégration de données
[Termes IGN] modèle dynamique
[Termes IGN] Normalized Difference Vegetation Index
[Termes IGN] SahelRésumé : (Auteur) This paper presents a method to monitor the dynamics of herbaceous vegetation in the Sahel. The approach is based on the assimilation of Normalized Difference Vegetation Index (NDVI) data acquired by the VEGETATION instrument on board SPOT 4/5 into a simple sahelian vegetation dynamics model. The study region is located in the Gourma region of Mali. The vegetation dynamics model is coupled with a radiative transfer model (the SAIL model). First, it is checked that the coupled models allow for a realistic simulation of the seasonal and interannual variability of NDVI over three sampling sites from 1999 to 2004. The data assimilation scheme relies on a parameter identification technique based on an Evolution Strategies algorithm. The simulated above-ground herbage mass resulting from NDVI assimilation is then compared to ground measurements performed over 13 study sites during the period 1999–2004. The assimilation scheme performs well with 404 kg DM/ha of average error (n = 126 points) and a correlation coefficient of r = 0.80 (to be compared to the 463 kg DM/ha and r = 0.60 of the model performance without data assimilation). Finally, the sensitivity of the herbage mass model estimates to the quality of the meteorological forcing (rainfall and net radiation) is analyzed thanks to a stochastic approach. Copyright Elsevier Numéro de notice : A2008-093 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2007.02.041 En ligne : https://doi.org/10.1016/j.rse.2007.02.041 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29088
in Remote sensing of environment > vol 112 n° 4 (15/04/2008) . - pp 1381 - 1394[article]The early explanatory power of NDVI in crop yield modelling / L. Wall in International Journal of Remote Sensing IJRS, vol 29 n° 7 (April 2008)
[article]
Titre : The early explanatory power of NDVI in crop yield modelling Type de document : Article/Communication Auteurs : L. Wall, Auteur ; D. Larocque, Auteur ; et al., Auteur Année de publication : 2008 Article en page(s) : pp 2211 - 2225 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse comparative
[Termes IGN] analyse diachronique
[Termes IGN] blé (céréale)
[Termes IGN] Canada
[Termes IGN] image NOAA-AVHRR
[Termes IGN] indice d'humidité
[Termes IGN] Normalized Difference Vegetation Index
[Termes IGN] prévision
[Termes IGN] rendement agricole
[Termes IGN] série temporelleRésumé : (Auteur) The objective of this paper is to study, on a weekly basis, the explanatory power of one satellite-based measurement, the Normalized Difference Vegetation Index (NDVI), for wheat yield modelling in 40 census agricultural regions (CAR) in the Canadian Prairies during the whole growing season using 16 years of NOAA AVHRR satellite data (between 1987 and 2002). We also explore the relative value of NDVI compared with a land-based measurement, the Cumulative Moisture Index (CMI). By developing a series of weekly wheat yield models over the course of the growing season, we are able to determine the accuracy of different models. Our findings indicate that NDVI possesses explanatory power 4 weeks earlier in the season than CMI. Copyright Taylor & Francis Numéro de notice : A2008-099 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160701395252 En ligne : https://doi.org/10.1080/01431160701395252 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29094
in International Journal of Remote Sensing IJRS > vol 29 n° 7 (April 2008) . - pp 2211 - 2225[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 080-08051 RAB Revue Centre de documentation En réserve L003 Disponible Assessment of the influence of flying altitude and scan angle on biophysical vegetation products derived from airborne laser scanning / F. Morsdorf in International Journal of Remote Sensing IJRS, vol 29 n° 5 (March 2008)
[article]
Titre : Assessment of the influence of flying altitude and scan angle on biophysical vegetation products derived from airborne laser scanning Type de document : Article/Communication Auteurs : F. Morsdorf, Auteur ; O. Frey, Auteur ; E. Meier, Auteur ; et al., Auteur Année de publication : 2008 Article en page(s) : pp 1387 - 1406 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] altitude du capteur
[Termes IGN] angle d'incidence
[Termes IGN] angle de visée
[Termes IGN] couvert végétal
[Termes IGN] données laser
[Termes IGN] hauteur des arbres
[Termes IGN] instrumentation Toposys
[Termes IGN] Leaf Area Index
[Termes IGN] modèle numérique de terrain
[Termes IGN] parc naturel
[Termes IGN] plan de vol
[Termes IGN] signal laser
[Termes IGN] Suisse
[Termes IGN] télémétrie laser aéroportéRésumé : (Auteur) Airborne Laser Scanning (ALS) has been established as a valuable tool for the estimation of biophysical vegetation properties such as tree height, crown width, fractional cover and leaf area index (LAI). It is expected that the conditions of data acquisition, such as viewing geometry and sensor configuration influence the value of these parameters. In order to gain knowledge about these different conditions, we test for the sensitivity of vegetation products for viewing geometry, namely flying altitude and scanning (incidence) angle. Based on two methodologies for single tree extraction and derivation of fractional cover and LAI previously developed and published by our group, we evaluate how these variables change with either flying altitude or scanning angle. These are the two parameters which often need to be optimized towards the best compromise between point density and area covered with a single flight line, in order to reduce acquisition costs. Our test-site in the Swiss National Park was sampled with two nominal flying altitudes, 500 and 900 m above ground. Incidence angle and local incidence angle were computed based on the digital terrain model using a simple backward geocoding procedure. We divided the raw laser returns into several different incident angle classes based on the flight path data; the TopoSys Falcon II system used in this study has a maximum scan angle of + 7.15°. We compared the derived biophysical properties from each of these classes with field measurements based on tachymeter measurements and hemispherical photographs, which were geolocated using differential GPS. It was found that with increasing flying height the well-known underestimation of tree height increases. A similar behaviour can be observed for fractional cover; its respective values decrease with higher flying height. The minimum distance between first and last echo increases from 1.2 metres for 500 m AGL to more than 3 metres for 900 m AGL, which does alter return statistics. The behaviour for incidence angles is not so evident, probably due to the small scanning angle of the system used. fCover seems to be most affected by incidence angles, with significantly higher differences for locations further away from nadir. As expected, incidence angle appears to be of higher importance for vegetation density parameters than local incidence angle. Numéro de notice : A2008-081 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160701736349 En ligne : https://doi.org/10.1080/01431160701736349 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29076
in International Journal of Remote Sensing IJRS > vol 29 n° 5 (March 2008) . - pp 1387 - 1406[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 080-08031 RAB Revue Centre de documentation En réserve L003 Exclu du prêt Adjusting for long term anomalous trends in NOAA's Global Vegetation Index datasets / L. Jiang in IEEE Transactions on geoscience and remote sensing, vol 46 n° 2 (February 2008)
[article]
Titre : Adjusting for long term anomalous trends in NOAA's Global Vegetation Index datasets Type de document : Article/Communication Auteurs : L. Jiang, Auteur ; D. Tarpley, Auteur ; K. Mitchell, Auteur ; et al., Auteur Année de publication : 2008 Article en page(s) : pp 409 - 422 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] correction
[Termes IGN] erreur systématique
[Termes IGN] image NOAA-AVHRR
[Termes IGN] modèle météorologique
[Termes IGN] Normalized Difference Vegetation Index
[Termes IGN] occupation du sol
[Termes IGN] sécheresse
[Termes IGN] stabilitéRésumé : (Auteur) The weekly 0.144° resolution global vegetation index from the National Oceanic and Atmospheric Administration (NOAA) National Environmental Satellite, Data, and Information Service (NESDIS) has a long history, starting late 1981, and has included data derived from Advanced Very High Resolution Radiometer (AVHRR) sensors onboard NOAA-7, -9, -11, -14, -16, -17, and -18 satellites. Even after postlaunch calibration and mathematical smoothing and filtering of the normalized difference vegetation index (NDVI) derived from AVHRR visible and near-infrared channels, the time series of global smoothed NDVI (SMN) still has apparent discontinuities and biases due to sensor degradation, orbital drift [equator crossing time (ECT)], and differences from instrument to instrument in band response functions. To meet the needs of the operational weather and climate modeling and monitoring community for a stable long-term global NDVI data set, we investigated adjustments to substantially reduce the bias of the weekly global SMN series by simple and efficient algorithms that require a minimum number of assumptions about the statistical properties of the interannual global vegetation changes. Of the algorithms tested, we found the adjusted cumulative distribution function (ACDF) method to be a well-balanced approach that effectively eliminated most of the long-term global-scale interannual trend of AVHRR NDVI. Improvements to the global and regional NDVI data stability have been demonstrated by the results of ACDF-adjusted data set evaluated at a global scale, on major land classes, with relevance to satellite ECT, at major continental regions, and at regional drought detection applications. Copyright IEEE Numéro de notice : A2008-072 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2007.902844 En ligne : https://doi.org/10.1109/TGRS.2007.902844 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29067
in IEEE Transactions on geoscience and remote sensing > vol 46 n° 2 (February 2008) . - pp 409 - 422[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-08021 RAB Revue Centre de documentation En réserve L003 Disponible People, pixels and weights in Vanderburgh County, Indiana: toward a new urban geography of human-environment interactions / E.W. Lafary in Geocarto international, vol 23 n° 1 (February - March 2008)PermalinkSpatially and temporally continuous LAI data sets based on an integrated filtering method: examples from North America / H. Fang in Remote sensing of environment, vol 112 n° 1 (15/01/2008)PermalinkApplications of remote sensing and Geographic Information Systems to assess ferrous minerals and iron oxide of Tokat province in Turkey / H.M. Dogan in International Journal of Remote Sensing IJRS, vol 29 n°1-2 (January 2008)PermalinkDetection of nickel-induced stress using laser-induced fluorescence signatures from leaves of wheat seedlings / K.B. Mishra in International Journal of Remote Sensing IJRS, vol 29 n°1-2 (January 2008)PermalinkUtilisation de la télédétection optique et radar pour étudier la déforestation en Afrique centrale / Quentin Page (2008)PermalinkShort-term response of Arctic vegetation NDVI to temperature anomalies / I. Olthof in International Journal of Remote Sensing IJRS, vol 28 n° 21-22 (November 2007)PermalinkLandsat ETM+ image applications to extract information for environmental planning in a Colombian city / L.M. Santana in International Journal of Remote Sensing IJRS, vol 28 n°19-20 (October 2007)PermalinkSensibilité des indices de diversité à l'agrégation / I. Mahfoud in Revue internationale de géomatique, vol 17 n° 3-4 (septembre 2007 – février 2008)PermalinkRule-based classification of multi-temporal satellite imagery for habitat and agricultural land cover mapping / Robert Lucas in ISPRS Journal of photogrammetry and remote sensing, vol 62 n° 3 (August 2007)PermalinkComparison and validation of MODIS and VEGETATION global LAI products over four BigFoot sites in North America / J. Pisek in Remote sensing of environment, vol 109 n° 1 (12 July 2007)Permalink