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Auteur Fengmei Yao |
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A two-scale approach for estimating forest aboveground biomass with optical remote sensing images in a subtropical forest of Nepal / Upama A. Koju in Journal of Forestry Research, vol 30 n° 6 (December 2019)
[article]
Titre : A two-scale approach for estimating forest aboveground biomass with optical remote sensing images in a subtropical forest of Nepal Type de document : Article/Communication Auteurs : Upama A. Koju, Auteur ; Jiahua Zhang, Auteur ; Shashish Maharjan, Auteur ; Sha Zhang, Auteur ; Yun Bai, Auteur ; Dinesh Babu Irulappa-Pillai-Vijayakumar , Auteur ; Fengmei Yao, Auteur Année de publication : 2019 Projets : 3-projet - voir note / Article en page(s) : pp 2119 - 2136 Note générale : bibliographie
The work was supported by the CAS Strategic Priority Research Program (No. XDA19030402), the National Key Research and Development Program of China (No. 2016YFD0300101), the Natural Science Foundation of China (Nos. 31571565, 31671585), the Key Basic Research Project of the Shandong Natural Science Foundation of China (No. ZR2017ZB0422), and Research Funding of Qingdao University (No. 41117010153).Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse d'image orientée objet
[Termes IGN] analyse multiéchelle
[Termes IGN] biomasse aérienne
[Termes IGN] biomasse forestière
[Termes IGN] Google Earth
[Termes IGN] image Geoeye
[Termes IGN] image Landsat
[Termes IGN] image optique
[Termes IGN] image Quickbird
[Termes IGN] NépalRésumé : (auteur) Forests account for 80% of the total carbon exchange between the atmosphere and terrestrial ecosystems. Thus, to better manage our responses to global warming, it is important to monitor and assess forest aboveground carbon and forest aboveground biomass (FAGB). Different levels of detail are needed to estimate FAGB at local, regional and national scales. Multi-scale remote sensing analysis from high, medium and coarse spatial resolution data, along with field sampling, is one approach often used. However, the methods developed are still time consuming, expensive, and inconvenient for systematic monitoring, especially for developing countries, as they require vast numbers of field samples for upscaling. Here, we recommend a convenient two-scale approach to estimate FAGB that was tested in our study sites. The study was conducted in the Chitwan district of Nepal using GeoEye-1 (0.5 m), Landsat (30 m) and Google Earth very high resolution (GEVHR) Quickbird (0.65 m) images. For the local scale (Kayerkhola watershed), tree crowns of the area were delineated by the object-based image analysis technique on GeoEye images. An overall accuracy of 83% was obtained in the delineation of tree canopy cover (TCC) per plot. A TCC vs. FAGB model was developed based on the TCC estimations from GeoEye and FAGB measurements from field sample plots. A coefficient of determination (R2) of 0.76 was obtained in the modelling, and a value of 0.83 was obtained in the validation of the model. To upscale FAGB to the entire district, open source GEVHR images were used as virtual field plots. We delineated their TCC values and then calculated FAGB based on a TCC versus FAGB model. Using the multivariate adaptive regression splines machine learning algorithm, we developed a model from the relationship between the FAGB of GEVHR virtual plots with predictor parameters from Landsat 8 bands and vegetation indices. The model was then used to extrapolate FAGB to the entire district. This approach considerably reduced the need for field data and commercial very high resolution imagery while achieving two-scale forest information and FAGB estimates at high resolution (30 m) and accuracy (R2 = 0.76 and 0.7) with minimal error (RMSE = 64 and 38 tons ha−1) at local and regional scales. This methodology is a promising technique for cost-effective FAGB and carbon estimations and can be replicated with limited resources and time. The method is especially applicable for developing countries that have low budgets for carbon estimations, and it is also applicable to the Reducing Emissions from Deforestation and Forest Degradation (REDD +) monitoring reporting and verification processes. Numéro de notice : A2019-664 Affiliation des auteurs : LIF+Ext (2012-2019) Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s11676-018-0743-1 Date de publication en ligne : 09/07/2018 En ligne : https://doi.org/10.1007/s11676-018-0743-1 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99699
in Journal of Forestry Research > vol 30 n° 6 (December 2019) . - pp 2119 - 2136[article]A comparative analysis of the NDVIg and NDVI3g in monitoring vegetation phenology changes in the Northern Hemisphere / Qing Chang in Geocarto international, vol 33 n° 1 (January 2018)
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Titre : A comparative analysis of the NDVIg and NDVI3g in monitoring vegetation phenology changes in the Northern Hemisphere Type de document : Article/Communication Auteurs : Qing Chang, Auteur ; Jiahua Zhang, Auteur ; Wenzhe Jiao, Auteur ; Fengmei Yao, Auteur Année de publication : 2018 Article en page(s) : pp 1 - 20 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] analyse comparative
[Termes IGN] analyse spatio-temporelle
[Termes IGN] données spatiotemporelles
[Termes IGN] hémisphère Nord
[Termes IGN] image NOAA-AVHRR
[Termes IGN] Normalized Difference Vegetation Index
[Termes IGN] phénologie
[Termes IGN] surveillance de la végétation
[Vedettes matières IGN] Végétation et changement climatiqueRésumé : (Auteur) Phenology is a sensitive and critical feature of vegetation and is a good indicator for climate change studies. The global inventory modelling and mapping studies (GIMMS) normalized difference vegetation index (NDVI) has been the most widely used data source for monitoring of the vegetation dynamics over large geographical areas in the past two decades. With the release of the third version of the NDVI (GIMMS NDVI3g) recently, it is important to compare the NDVI3g data with those of the previous version (NDVIg) to link existing studies with future applications of the NDVI3g in monitoring vegetation phenology. In this study, the three most popular satellite start of vegetation growing season (SOS) extraction methods were used, and the differences between SOSg and SOS3g arising from the methods were explored. The amplitude and the peak values of the NDVI3g are higher than those of the NDVIg curve, which indicated that the SOS derived from the NDVIg (SOSg) was significantly later than that derived from the NDVI3g (SOS3g) based on all the methods, for the whole northern hemisphere. In addition, SOSg and SOS3g both showed an advancing trend during 1982–2006, but that trend was more significant with SOSg than with SOS3g in the results from all three methods. In summary, the difference between SOSg and SOS3g (in the multi-year mean SOS, SOS change slope and the turning point in the time series) varied among the methods and was partly related to latitude. For the multi-year mean SOS, the difference increased with latitude intervals in the low latitudes (0–30°N) and decreased in the mid- and high-latitude intervals. The GIMMS NDVI3g data-sets seemed more sensitive than the GIMMS NDVIg in detecting information about the ground, and the SOS3g data were better correlated both with the in situ observations and the SOS derived from the Moderate Resolution Imaging Spectroradiometer NDVI. For the northern hemisphere, previous satellite measures (SOS derived from GIMMS NDVIg) may have overestimated the advancing trend of the SOS by an average of 0.032 d yr–1. Numéro de notice : A2018-029 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106049.2016.1222633 En ligne : https://doi.org/10.1080/10106049.2016.1222633 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=89198
in Geocarto international > vol 33 n° 1 (January 2018) . - pp 1 - 20[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 059-2018011 RAB Revue Centre de documentation En réserve L003 Disponible Simulating urban growth processes by integrating cellular automata model and artificial optimization in Binhai New Area of Tianjin, China / Fengmei Yao in Geocarto international, vol 31 n° 5 - 6 (May - June 2016)
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Titre : Simulating urban growth processes by integrating cellular automata model and artificial optimization in Binhai New Area of Tianjin, China Type de document : Article/Communication Auteurs : Fengmei Yao, Auteur ; Cui Hao, Auteur ; Jiahua Zhang, Auteur Année de publication : 2016 Article en page(s) : pp 612 - 627 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] automate cellulaire
[Termes IGN] Chine
[Termes IGN] intelligence artificielle
[Termes IGN] optimisation par essaim de particules
[Termes IGN] simulation
[Termes IGN] surveillance de l'urbanisation
[Termes IGN] urbanisationRésumé : (Auteur) This study presents an optimized algorithm into the cellular automata (CA) models for urban growth simulation in Binhai New Area of Tianjin, China. The optimized CA model by particle swarm optimization (PSO) was compared with the logistic-based cellular automata (LOGIT-CA) model to see the effects of the simulation. The study evaluated the stochastic disturbance in the development of urban growth using the Monte Carlo method; the coefficient d determined the state of urban growth. The validation was conducted by both cross-tabulation test and structural measurements. The results showed that the simulations of PSO-CA were better than LOGIT-CA model, indicating an improvement in the spatio-temporal simulation of urban growth and land use changes in study area. Since the simulations reached their best values when the coefficient was between 1 and 2, the urban growth in the study area was in the period of conversion from spontaneous growth to edge-expansion and infilling growth. Numéro de notice : A2016-172 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106049.2015.1073365 Date de publication en ligne : 14/08/2015 En ligne : http://www.tandfonline.com/doi/full/10.1080/10106049.2015.1073365 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80516
in Geocarto international > vol 31 n° 5 - 6 (May - June 2016) . - pp 612 - 627[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 059-2016031 RAB Revue Centre de documentation En réserve L003 Disponible