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Long-term changes in forest productivity: a consistent assessment in even-aged stands / Jean-Daniel Bontemps in Forest science, vol 55 n° 6 (December 2009)
[article]
Titre : Long-term changes in forest productivity: a consistent assessment in even-aged stands Type de document : Article/Communication Auteurs : Jean-Daniel Bontemps , Auteur ; Jean-Christophe Hervé (1961-2017) , Auteur ; Jean-François Dhôte, Auteur Année de publication : 2009 Article en page(s) : pp 549 - 564 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] analyse diachronique
[Termes IGN] croissance des arbres
[Termes IGN] Fagus sylvatica
[Termes IGN] forêt
[Termes IGN] hauteur des arbres
[Termes IGN] productivitéRésumé : (auteur) The objective of the study was to provide a stand-scale assessment of long-term productivity changes in even-aged stands and to depict their chronology over the twentieth century. We focused on dominant height growth as a proxy for productivity, reconstructed from stem analyses in temporary plots. Height increments from two generations of stands were compared. Stands were associated in pairs to ensure accurate control of intrinsic site fertility conditions. The historical evolution of the growth rate was estimated using a statistical modeling approach based on a mixed-effects model, with a control of both site and developmental stage effects. We placed emphasis on a model formulation that leads to a meaningful interpretation of growth rate evolution. We applied the methodology to a sample of 14 stand pairs and 84 stem analyses of Common Beech in northeastern France. An accelerated increase in growth rate was identified, reaching +50% over the twentieth century. The trend also displayed short-term growth anomalies. Numéro de notice : A2009-394 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1093/forestscience/55.6.549 Date de publication en ligne : 01/12/2009 En ligne : https://doi.org/10.1093/forestscience/55.6.549 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83084
in Forest science > vol 55 n° 6 (December 2009) . - pp 549 - 564[article]Diversity and primary productivity of hill beech forests from Doftana Valley (Romanian Subcarpathians) / Mihaela Pauca-Comanescu in Annals of forest research, vol 52 n° 1 (January 2009)
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Titre : Diversity and primary productivity of hill beech forests from Doftana Valley (Romanian Subcarpathians) Type de document : Article/Communication Auteurs : Mihaela Pauca-Comanescu, Auteur ; Mihaela Pauca-Comanescu, Auteur ; Marinela Onete, Auteur ; Vasile Sanda, Auteur ; Ioana Vicol, Auteur ; Ioana Onut, Auteur ; Daniela Mogaldea, Auteur ; Sorin Stefanut, Auteur Année de publication : 2009 Article en page(s) : p. 63-76 Note générale : Bibliogr. Langues : Anglais (eng) Descripteur : [Termes IGN] biodiversité
[Termes IGN] biomasse aérienne
[Termes IGN] Fagus sylvatica
[Termes IGN] productivité
[Termes IGN] Roumanie
[Vedettes matières IGN] Economie forestièreRésumé : (Auteur) "The hill beech forests cover most of the woody area in the Doftana Valley. The present study refers, for the first time, to two beech forests typical to this belt, which belong to the phytocoenological associations Epipactieto-Fagetum (Resmeriţă, 1972), in the Lunca Mare area, and Hieracio rotundati-Fagetum (Vida 1983, Täuber 1987) in the Sotrile area, from floristic, structural, biomass and necromass accumulation point of view, within the framework of the vertical structure of biocoenosis. The limestone substratum, occasionally with small outcrops in the first beech forest, differs chiefly through the pH levels (6.34-5.67) from the siliceous substratum (pH 5.11-4.36) in the second beech forest. The layer of trees is dominated by Fagus sylvatica in both forests; this species is associated with Cerasus avium (4.5%), Acer pseudoplatanus (2%) and Sorbus torminalis (2%) in the first beech forest, and is monodominant in the second. Although the forest underwent selective cuts, more intense in the Lunca Mare area, the aboveground ligneous biomass reaches nowadays 222 t/ha in the Lunca Mare area compared to only 163 t/ha in the Sotrile area; the average height is 28.8ą2.49 m and 23.7ą1.12 m, respectively, and the diameter is 33.30ą7.9 cm and 31.60ą6.28 cm, respectively. The species of macrofungi, not very numerous during the study because of scarce precipitations (6 and 7 species, respectively), are predominant on the rhytidoma trees in the beech forest rooted on the limestone ground; in the Sotrile beech forest they are joined by mycorrhizal and parasite species. The layer of shrub is underdeveloped. The herbaceous layer is discontinuous, and includes, along herbs, small plants and saplings belonging to the ligneous species and to liana Hedera helix. The maximal value of the aboveground biomass of the layer is 317 kg/ha DM in the Lunca Mare area and 235 kg /ha DM in the Sotrile area. Bryophyta is present in large quantities, especially in the Sotrile area, where by May it represents up to 20% of the inferior layer's biomass; on the limestone ground they do not exceed 0.5%. The most frequent are on the soil surface: Polytrichum formosum, Pogonatum nanum, Hypnum cupressiforme, Tortella tortuosa at Sotrile and, respectively Metzgeria furcata var. ulvula, Leskea nervosa , Ctenidium molluscum at Lunca Mare. In the Lunca Mare area, the most relevant herbaceous species in the structure of the biomass are Viola reichenbachiana, Festuca drymeja, Sanicula europaea and Campanula trachelium; in spring there are also Erytronium dens-canis and Lathyrus vernus. In the Sotrile area these are: Luzula luzuloides, Carex digitata, Calamagrostis arundinacea and Hieracium transsylvanicum, in both spring and autumn. Hedera helix, present especially at the surface, is the most frequent and best represented in terms of biomass in both beech forests, and in particular in the Lunca Mare site. The species characteristic to the phytocoenological association and to the alliances where these beech forests are included are representative through their biomass for the Hieracio rotundati-Fagetum association, while the orchids species characteristic to associations present on the limestone ground, although very diverse and with a great number of individuals for this taxonomic group, are not representative, neither as frequency nor as biomass or density, compared to other herbal species with a larger coenotic value, which are included in the Epipactieto-Fagetum association. The necromass accumulated in the area analyzed decays slowly, varying greatly with surface and time. It averages 4492 kg/ha in the Lunca Mare area and 4134 kg/ha in the Sotrile area. The necromass is made mostly of fallen leaves, and, at least in the Lunca Mare area, the July values are amplified by vernal herb flora." Numéro de notice : IFN_5773 Affiliation des auteurs : non IGN Thématique : BIODIVERSITE/FORET Nature : Article DOI : sans En ligne : http://www.editurasilvica.ro/afr/52/1/06_Pauca.pdf Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=73496
in Annals of forest research > vol 52 n° 1 (January 2009) . - p. 63-76[article]Documents numériques
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Diversity and primary productivity of hill beech forests...Adobe Acrobat PDF The measurement of productive efficiency and productivity growth / Harold O. Fried (2008)
Titre : The measurement of productive efficiency and productivity growth Type de document : Monographie Auteurs : Harold O. Fried, Éditeur scientifique ; C. A. Knox Lovell, Éditeur scientifique ; Shelton S. Schmidt, Éditeur scientifique Editeur : Oxford, Londres, ... : Oxford University Press Année de publication : 2008 Importance : 638 p. Format : 16 x 24 cm ISBN/ISSN/EAN : 978-0-19-518352-8 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Statistiques
[Termes IGN] efficacité
[Termes IGN] inférence statistique
[Termes IGN] productivitéIndex. décimale : 23.60 Statistiques et probabilités Résumé : (éditeur) "This is an excellent collection of book-length essays on the three main approaches to productivity and efficiency measurement: the econometric, the nonparametric, and the index number approach. The authors, who are experts in the various domains, succeed in providing highly readable surveys of the rich flow of literature that started in the late 1970s, and in giving introductions that are primarily aimed at newcomers but also interesting for experienced researchers. The many applications that are spread through the chapters give the reader a good idea of how to carry out performance assessment in practice. This book has a lot to offer a variety of readers."--Bert M. Balk, Statistics Netherlands and RSM Erasmus University
"Efficiency and productivity involve the 'best' use of scarce resources, which is the foundation of economic performance. The top specialists who have contributed to this volume unravel a fundamental but unresolved issue of economic performance--that extensive real-world variability in firms' economic performance belies the homogeneity implied by economic theory. They evaluate the pieces of the puzzle--inefficiencies involving technical, cost and revenue optimization--that cause firms to deviate from best-practice operation, and explain how such deviations can be measured and explained to further business performance and competitiveness. This is an excellent and comprehensive reference for any researcher interested in the analysis of economic performance, and the recent advances made and challenges still ahead in this field."--Catherine J. Morrison Paul, Professor, Department of Agricultural and Resource Economics, University of California, Davis and member of the Giannini FoundationNote de contenu : 1. Efficiency and Productivity / Harold O. Fried, C.A. Knox Lovell, and Shelton S. Schmidt
2. The Econometric Approach to Efficiency Analysis / William H. Greene
3. Data Envelopment Analysis : The Mathematical Programming Approach to Efficiency Analysis / Emmanuel Thanassoulis, Maria C.S. Portela, and Ozren Despić
4. Statistical Inference in Nonparametric Frontier Models : Recent Developments and Perspectives / Léopold Simar and Paul W. Wilson
5. Efficiency and Productivity : Malmquist and More / Rolf Färe, Shawna Grosskopf, and Dimitri MargaritisNuméro de notice : 17032 Affiliation des auteurs : non IGN Thématique : MATHEMATIQUE Nature : Recueil / ouvrage collectif Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=66958 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 17032-01 23.60 Livre Centre de documentation Mathématiques Disponible Estimate of net primary productivity of aquatic vegetation of the Amazon floodplain using Radarsat and JERS-1 / M. Costa in International Journal of Remote Sensing IJRS, vol 26 n° 20 (October 2005)
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Titre : Estimate of net primary productivity of aquatic vegetation of the Amazon floodplain using Radarsat and JERS-1 Type de document : Article/Communication Auteurs : M. Costa, Auteur Année de publication : 2005 Article en page(s) : pp 4527 - 4536 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] Amazone (fleuve)
[Termes IGN] image JERS
[Termes IGN] image radar
[Termes IGN] image Radarsat
[Termes IGN] macrophyte
[Termes IGN] masse végétale
[Termes IGN] modèle conceptuel de données localisées
[Termes IGN] productivitéRésumé : (Auteur) Synthetic aperture radar images, combined with field measurements, were used to estimate net primary productivity (NPP) of aquatic vegetation in the lower Amazon. Input data for a NPP model are (i) the total biomass of aquatic vegetation, determined by radar imagery and field measurements and (ii) the area occupied by aquatic vegetation, determined from radar imagery. After correction for monthly biomass losses, the NPP of one growth cycle of aquatic vegetation was calculated in the image domain. The total net primary productivity of Hymenachne amplexicaitles, the dominant aquatic vegetation in the area, was on average 19 x 1011 gC yr-1 for the entire area. Spatially, lower values of produced organic carbon ( 5000 g Cm-2 yr-1) in areas closer to the Amazon River where the availability and influence of nutrient-rich water is greater. Numéro de notice : A2005-465 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/01431160500213433 En ligne : https://doi.org/10.1080/01431160500213433 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27601
in International Journal of Remote Sensing IJRS > vol 26 n° 20 (October 2005) . - pp 4527 - 4536[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 080-05201 RAB Revue Centre de documentation En réserve L003 Exclu du prêt
Titre : An introduction to efficiency and productivity analysis Type de document : Monographie Auteurs : Thimoty J. Coelli, Auteur ; D. S. Prasada Rao, Auteur ; George E. Battese, Auteur ; Christopher J. O'Donnell, Auteur Mention d'édition : 2d edition Editeur : Berlin, Heidelberg, Vienne, New York, ... : Springer Année de publication : 2005 Importance : 349 p. Format : 16 x 24 cm ISBN/ISSN/EAN : 978-0-387-24266-8 Prix : 48 EUR Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Statistiques
[Termes IGN] coût
[Termes IGN] optimisation (mathématiques)
[Termes IGN] productivité
[Termes IGN] statistique mathématiqueIndex. décimale : 23.60 Statistiques et probabilités Résumé : (éditeur) The second edition of An Introduction to Efficiency and Productivity Analysis is designed to be a general introduction for those who wish to study efficiency and productivity analysis. The book provides an accessible, well-written introduction to the four principal methods involved: econometric estimation of average response models; index numbers, data envelopment analysis (DEA); and stochastic frontier analysis (SFA). For each method, a detailed introduction to the basic concepts is presented, numerical examples are provided, and some of the more important extensions to the basic methods are discussed. Of special interest is the systematic use of detailed empirical applications using real-world data throughout the book.In recent years, there have been a number of excellent advance-level books published on performance measurement. This book, however, is the first systematic survey of performance measurement with the express purpose of introducing the field to a wide audience of students, researchers, and practitioners. Indeed, the 2nd Edition maintains its uniqueness: (1) It is a well-written introduction to the field. (2) It outlines, discusses and compares the four principal methods for efficiency and productivity analysis in a well-motivated presentation. (3) It provides detailed advice on computer programs that can be used to implement these performance measurement methods. The book contains computer instructions and output listings for the SHAZAM, LIMDEP, TFPIP, DEAP and FRONTIER computer programs. Note de contenu : 1- Introduction
2- Review of production economics
3- Productivity and efficiency measurement concepts
4- Index numbers and productivity measurement
5- Data and measurement issues
6- Data envelopment analysis
7- Additional topics on data envelopment analysis
8- Econometric estimation of production technologies
9- Stochastic frontier analysis
10- Additional topics on stochastic frontier analysis
11- The calculation and decomposition of productivity change using frontier methods
12- ConclusionsNuméro de notice : 17025 Affiliation des auteurs : non IGN Thématique : MATHEMATIQUE Nature : Monographie En ligne : http://www.uq.edu.au/economics/cepa/crob2005 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=66959 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 17025-01 23.60 Livre Centre de documentation Mathématiques Disponible Increasing imaging productivity with improved hardware: graphics requirements and spatial data / S. Recine in Geoinformatics, vol 7 n° 8 (01/12/2004)PermalinkInfluence passée, présente et à venir de la technologie en topographie / D. Wallace in XYZ, n° 99 (juin - août 2004)PermalinkChlorophyll-a estimation in New-Jersey's coastal waters using Thematic Mapper data / S. Bagheri in International Journal of Remote Sensing IJRS, vol 11 n° 2 (February 1990)PermalinkEstimating forest productivity with Thematic Mapper and biogeographical data / E.A. Cook in Remote sensing of environment, vol 28 n° 1 (April - June 1989)PermalinkRelating seasonal patterns of the AVHRR vegetation index to simulated photosynthesis and transpiration of forests in different climates / S.W. Running in Remote sensing of environment, vol 24 n° 2 (March 1988)PermalinkRelating Nimbus-7 37GhZ data to global land-surface evaporation, primary productivity and the atmospheric C02 concentration / B.J. Choudhury in International Journal of Remote Sensing IJRS, vol 9 n° 1 (January 1988)PermalinkEstimates of primary productivity over the Thar desert based upon nimbus-7 37GHZ data : 1979-1985 / B.J. Choudhury in International Journal of Remote Sensing IJRS, vol 8 n° 12 (December 1987)PermalinkCarte des sols et carte des terres agricoles / Jean-Philippe Grelot in Bulletin d'information de l'Institut géographique national, n° 49 (mars 1984)PermalinkProblèmes de compromis entre représentation graphique et géomatique / B. Dubuisson in XYZ, n° 5 (décembre 1980 - février 1981)Permalink