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Comparative analysis on utilisation of linear spectral unmixing and band ratio methods for processing ASTER data to delineate bauxite over a part of Chotonagpur plateau, Jharkhand, India / Arindam Guha in Geocarto international, vol 31 n° 3 - 4 (March - April 2016)
[article]
Titre : Comparative analysis on utilisation of linear spectral unmixing and band ratio methods for processing ASTER data to delineate bauxite over a part of Chotonagpur plateau, Jharkhand, India Type de document : Article/Communication Auteurs : Arindam Guha, Auteur ; K. Vinod Kumar, Auteur Année de publication : 2016 Article en page(s) : pp 367 - 384 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image mixte
[Termes IGN] aluminium
[Termes IGN] analyse comparative
[Termes IGN] analyse discriminante
[Termes IGN] analyse linéaire des mélanges spectraux
[Termes IGN] image hyperspectrale
[Termes IGN] image Terra-ASTER
[Termes IGN] Inde
[Termes IGN] mineraiRésumé : (Auteur) We have attempted comparative analysis of the utility of linear spectral unmixing (LSU) method and band ratios for delineating bauxite from laterite within the lateritic bauxite provinces of Chotonagpur Plateau, Jharkhand of India. This was attempted based on processing of visible–near infrared (VNIR) and shortwave infrared (SWIR) spectral bands of Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) sensor. In LSU method, spectral features of main constituent minerals of lateritic bauxite are used to decompose the pixel spectra to estimate the relative abundance of bauxite and laterite in each pixel to spatially delineate bauxite within laterite. We have also compared the bauxite map derived using LSU method with bauxite maps of two band ratios in terms of spatial disposition of bauxite. We also have attempted to relate the abundance values of pixels of LSU-based bauxite map with band ratio values of bauxite pixels of two selected bauxite indices. Numéro de notice : A2016-155 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106049.2015.1047471 Date de publication en ligne : 10/06/2015 En ligne : http://www.tandfonline.com/doi/full/10.1080/10106049.2015.1047471 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80395
in Geocarto international > vol 31 n° 3 - 4 (March - April 2016) . - pp 367 - 384[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 059-2016021 RAB Revue Centre de documentation En réserve L003 Disponible Plant community mycorrhization in temperate forests and grasslands: relations with edaphic properties and plant diversity / Maret Gerz in Journal of vegetation science, vol 27 n° 1 (January 2016)
[article]
Titre : Plant community mycorrhization in temperate forests and grasslands: relations with edaphic properties and plant diversity Type de document : Article/Communication Auteurs : Maret Gerz, Auteur ; Carlos Guillermo Bueno, Auteur ; Martin Zobel, Auteur ; Mari Moora, Auteur Année de publication : 2016 Article en page(s) : pp 89 - 99 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] azote
[Termes IGN] biodiversité végétale
[Termes IGN] ectomycorhize
[Termes IGN] Estonie
[Termes IGN] forêt tempérée
[Termes IGN] humidité du sol
[Termes IGN] prairie
[Vedettes matières IGN] Ecologie forestièreRésumé : (auteur) Questions : Mycorrhizal symbiosis plays a key role in plant communities. Its prevalence in plant communities (mycorrhization) at larger spatial scales has so far been mostly qualitative, while quantitative studies incorporating the mycorrhizal traits of plant species are scarce. This study aims to: (1) determine the variation in general and arbuscular mycorrhization in temperate forests and grasslands, (2) study the effects of soil N, pH and moisture on mycorrhization, and (3) determine the relationships between mycorrhization and plant diversity.
Location : Temperate forests and grasslands in Estonia, Northern Europe.
Methods : To quantify mycorrhization we used a plant community mycorrhization index – community mean of mycorrhizal status weighted by plant species abundances. The effects of edaphic factors characterized by cumulative Ellenberg values on mycorrhization were analysed using linear mixed models, and the relationship between mycorrhization and diversity was evaluated with partial correlation and variance partitioning.
Results : General mycorrhization was higher in forests and lower in grasslands, opposite to arbuscular mycorrhization. Soil N, pH and moisture negatively impacted general mycorrhization, whereas arbuscular mycorrhization was positively affected by soil pH and negatively by soil N and moisture. Plant species richness was negatively correlated with general mycorrhization in forests, whereas arbuscular mycorrhization was positively associated with plant species richness, Shannon and Simpson indices in forests and across ecosystems.
Conclusions : Mycorrhization is highly dependent on soil conditions and related to plant diversity, showing its importance for vegetation science. The plant community mycorrhization index used in this study is a promising tool for quantifying the prevalence of mycorrhizal symbiosis along environmental gradients.Numéro de notice : A2016-361 Affiliation des auteurs : non IGN Thématique : BIODIVERSITE/FORET Nature : Article DOI : 10.1111/jvs.12338 En ligne : http://dx.doi.org/10.1111/jvs.12338 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81096
in Journal of vegetation science > vol 27 n° 1 (January 2016) . - pp 89 - 99[article]Nighttime-lights-derived fossil fuel carbon dioxide emission maps and their limitations / Naizhuo Zhao in Photogrammetric Engineering & Remote Sensing, PERS, vol 81 n° 12 (December 2015)
[article]
Titre : Nighttime-lights-derived fossil fuel carbon dioxide emission maps and their limitations Type de document : Article/Communication Auteurs : Naizhuo Zhao, Auteur ; Eric L. Samson, Auteur ; Nathan A. Currit, Auteur Année de publication : 2015 Article en page(s) : pp 935 - 943 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse d'image numérique
[Termes IGN] cartographie des risques
[Termes IGN] dioxyde de carbone
[Termes IGN] éclairage public
[Termes IGN] luminance lumineuse
[Termes IGN] pollution lumineuse
[Termes IGN] prise de vue nocturneRésumé : (auteur) Brightness of nighttime lights has been used as an indicator for spatial disaggregation of CO2 emission based on an assumed linear relationship between the digital number (DN) values of nighttime light imagery and the amount of CO2 emissions. However, reliability of the linear relationship of these variables has not been thoroughly examined. In this study, we find that the actual overall correlations are exponential rather than linear. More specific analyses showed that the DN values of nighttime light imagery first behaves linearly (from 3 to 50) and then exponentially (from 51 to 63), correlating to the amount of CO2 emissions. Regardless of the use of a linear or piecewise function, some featured limitations are evident as we developed the methodology. Among significant limitations, CO2 emissions were not visualized in unlit areas and a lack of variation existed in regions with the same DN values of nighttime light imagery. Lastly CO2 emissions in urban core areas were grossly under-estimated. Numéro de notice : A2015-993 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.81.12.935 En ligne : https://doi.org/10.14358/PERS.81.12.935 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80274
in Photogrammetric Engineering & Remote Sensing, PERS > vol 81 n° 12 (December 2015) . - pp 935 - 943[article]Xylem and soil CO2 fluxes in a Quercus pyrenaica Willd. coppice: root respiration increases with clonal size / Roberto Salomón in Annals of Forest Science, vol 72 n° 8 (December 2015)
[article]
Titre : Xylem and soil CO2 fluxes in a Quercus pyrenaica Willd. coppice: root respiration increases with clonal size Type de document : Article/Communication Auteurs : Roberto Salomón, Auteur ; María Valbuena-Carabaña, Auteur ; Jesús Rodríguez-Calcerrada, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 1065-1078 Note générale : biblographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Végétation
[Termes IGN] dioxyde de carbone
[Termes IGN] Pyrénées (montagne)
[Termes IGN] Quercus (genre)
[Termes IGN] système radiculaire
[Termes IGN] taillisRésumé : (auteur) : Key message: Xylem and soil CO 2 fluxes in coppiced oak forests increase with clonal size, suggesting larger expenditures of energy for root respiration. An imbalance between root demand and shoot production of carbohydrates may contribute to the degradation of abandoned coppices.
Context: Our understanding of root respiration is limited, particularly in root-resprouting species with many stems and a large system of interconnected roots resulting from long-term coppicing.
Aims: We tested the hypothesis that clone size influences the internal flux of CO2 dissolved in xylem sap (F T) from roots into the stem and soil CO2 efflux (F S) as indicators of root respiration. We predicted that large clones would exhibit higher F T per stem and F S than small clones due to larger root system per stem in large clones.
Methods: Genetic analyses were performed to elucidate clonal grouping. F T was measured continuously for 100 days in 16 similar-sized stems of Quercus pyrenaica belonging to two large and two small clones. F S was measured in 20 clones of varying size.
Results: F T per stem and F S were higher in large clones. F T was 2 % of the root-respired CO2 that diffused through soil to the atmosphere.
Conclusions: Relative to other studies, the contribution of F T to root respiration was very low, pointing to large differences depending on species or site. Higher stem F T and F S in large clones compared with small clones suggest greater carbon consumption by roots in large clones, pointing to a root/shoot biomass and physiological imbalance resulting from long-term coppicing that would partially explain the degradation of currently abandoned stands of Q. pyrenaica.Numéro de notice : A2015-898 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1007/s13595-015-0504-7 Date de publication en ligne : 08/08/2015 En ligne : https://doi.org/10.1007/s13595-015-0504-7 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79455
in Annals of Forest Science > vol 72 n° 8 (December 2015) . - pp 1065-1078[article]Phosphorus nutrition of beech (Fagus sylvatica L.) is decreasing in Europe / Ulrike Talkne in Annals of Forest Science, vol 72 n° 7 (October 2015)
[article]
Titre : Phosphorus nutrition of beech (Fagus sylvatica L.) is decreasing in Europe Type de document : Article/Communication Auteurs : Ulrike Talkne, Auteur ; Karl Josef Meiwes, Auteur ; Nenad Potočić, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 919 - 928 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] azote
[Termes IGN] croissance des arbres
[Termes IGN] défoliation
[Termes IGN] Fagus (genre)
[Termes IGN] nutriment végétal
[Termes IGN] phosphore
[Termes IGN] phytobiologie
[Termes IGN] placette d'échantillonnage
[Termes IGN] sol acide
[Vedettes matières IGN] Végétation et changement climatiqueRésumé : (auteur) Key message : Foliar phosphorus concentrations have decreased in Europe during the last 20 years. High atmospheric nitrogen deposition and climate change might be responsible for this trend. Continued decrease in foliar P concentrations might lead to reduced growth and vitality of beech forests in Europe.
Context : Increased forest soil acidification, atmospheric nitrogen deposition, and climate change have been shown to affect phosphorus nutrition of forest trees. Low foliar phosphorus levels and high nitrogen/phosphorus ratios have been observed in different European countries and have been related to reduced growth in forests.
Aims : We test the hypothesis that phosphorus concentrations of European beech (F. sylvatica L.) foliage are decreasing at the European scale.
Methods : Foliar phosphorus concentrations in beech were monitored on the basis of the “International Co-operative Programme on Assessment and Monitoring of Air Pollution Effects on Forests.” Here, data from 12 European countries, comprising 79 plots and a 20-year sampling period (1991–2010), were evaluated.
Results : Foliar phosphorus concentrations ranged from 0.81 to 1.66 mg g−1 dw (plot median of the 20-year sampling period). On 22 % of the plots, phosphorus concentrations were in the deficiency range of beech (Mellert and Göttlein 2012). On 62 % of the plots, the nitrogen/phosphorus ratio was above 18.9, which is considered to be disharmonious for beech. In addition, foliar phosphorus concentrations were significantly decreasing by, on average, 13 % from 1.31 to 1.14 mg g−1 in Europe (p Conclusion : Our results show that phosphorus nutrition of beech is impaired in Europe. Possible drivers of this development might be high atmospheric nitrogen deposition and climate change. Continued decrease in foliar phosphorus concentrations, eventually attaining phosphorus deficiency levels, might lead to reduced growth and vitality of beech forests in Europe.Numéro de notice : A2015-719 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1007/s13595-015-0459-8 Date de publication en ligne : 01/10/2015 En ligne : https://doi.org/10.1007/s13595-015-0459-8 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=78368
in Annals of Forest Science > vol 72 n° 7 (October 2015) . - pp 919 - 928[article]Variables related to nitrogen deposition improve defoliation models for European forests / Marco Ferretti in Annals of Forest Science, vol 72 n° 7 (October 2015)PermalinkPrediction of the presence of topsoil nitrogen from spaceborne hyperspectral data / Binny Gopal in Geocarto international, vol 30 n° 1 - 2 (January - February 2015)PermalinkRegional gold potential mapping in Kelantan (Malaysia) using probabilistic based models and GIS / Suhaimizi Yusoff in Open geosciences, vol 7 n° 1 (January 2015)PermalinkSols et environnement, chiffres clés, édition 2015 / CGDD Commissariat Général au Développement Durable (2015)PermalinkAssessment of crop foliar nitrogen using a novel dual-wavelength laser system and implications for conducting laser-based plant physiology / Jan U.H. Eitel in ISPRS Journal of photogrammetry and remote sensing, vol 97 (November 2014)PermalinkUne ressource à faire fructifier durablement / Henri Plauche-Gillon in Géomètre, n° 2119 (novembre 2014)PermalinkCause-effect relationship among morphological adaptations, growth, and gas exchange response of pedunculate oak seedling to waterlogging / Fabienne Tatin-Froux in Annals of Forest Science, vol 71 n° 3 (April - May 2014)PermalinkNon-linear partial least square regression increases the estimation accuracy of grass nitrogen and phosphorus using in situ hyperspectral and environmental data / Abel Ramoelo in ISPRS Journal of photogrammetry and remote sensing, vol 82 (August 2013)PermalinkUne évaluation spatiale des risques agro-environnementaux par une modélisation multicritère combinée avec la méthode PIXAL / Francis Macary in Revue internationale de géomatique, vol 23 n° 1 (mars - mai 2013)PermalinkLandscape controls over major nutrients and primary productivity of Arctic lakes / P. Pathak in Cartography and Geographic Information Science, vol 39 n° 4 (October 2012)Permalink