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1. Hepatozoon cf. terzii (Sambon & Seligman, 1907) infection in the snake Boa constrictor constrictor from north Brazil: transmission to the mosquito Culex quinquefasciatus and the lizard Tropidurus torquatus

Author

Paperna I. and Lainson R.

Subjects
Hepatozoon cf. terzii, Boa constrictor constrictor, Tropidurus torquatus, Culex quinquefasciatus, life-cycle, Brazil, Infectious and parasitic diseases, RC109-216
Abstract

Specimens of Hepatozoon-infected Boa constrictor constrictor were obtained from localities in Pará State, north Brazil. Gametocytes in erythrocytes of the peripheral blood measured 10 x 2.5-16.2 x 3.7 µm. They were similar to those described as Haemogregarina terzii by Sambon & Seligmann (1907) in B. c. constrictor, in that they did not distort the infected erythrocyte, and their dimensions approximated those given by Carini (1947). Lungs and liver of infected snakes contained actively dividing meronts of a single type, and cysts containing two to six cystozoites were also present in the liver. Our initial feeding of Culex quinquefasciatus on infected snakes consistently resulted in a heavy death-rate of the engorged mosquitoes, with only a few surviving till the 9th day post feeding. These contained numerous oocysts which were undivided or in early stages of division. A fifth and final experiment, however, provided a few mosquitoes surviving up to 21 days post infection (dpi), and these contained fully sporulated oocysts measuring 190-200 µm in diameter and containing over 60 sporocysts of 19-30 µm in diameter. The number of sporozoites in each sporocyst was estimated as approximately 50. The nature of the parasite's sporogonic cycle in the mosquito thus justifies inclusion of this haemogregarine in the genus Hepatozoon. Two wild-caught specimens of the lizard Tropidurus torquatus were fed with mosquitoes containing fully developed oocysts (21 dpi). When sacrificed, three months later, large numbers of dizoic, tetrazoic and hexazoic cysts were demonstrated in their livers. Cystozoites released from these cysts were shown to possess a conspicuous refractile body.

Published
2004
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2. Plasmodium kentropyxi n.sp. (Apicomplexa: Haemosporina: Plasmodiidae) and a Plasmodium tropiduri-like parasite in the lizard Kentropyx calcarata (Lacertilia: Teiidae) in North Brazil

Author

Lainson R., Landau I., and Paperna I.

Subjects
Plasmodium kentropyxi n.sp., Plasmodium sp. (tropiduri-like), Kentropyx calcarata, lizards, Brazil, Infectious and parasitic diseases, RC109-216
Abstract

Plasmodium kentropyxi n.sp. is described in the teiid lizard Kentropyx calcarata from north Brazil. Young asexual stages and gametocytes are at first polar in the erythrocyte but with elongation, move to a lateral position. Largest meronts seen contained from 30-40 nuclei and conspicuous greenish-black pigment granules located in a distinct vacuole. With growth the gametocytes eventually assume a smooth, curved cylindrical shape, with evenly rounded ends. Pigment is scattered or concentrated around a conspicuous vacuole which is slowly developed as the gametocytes mature. Mature male parasites measured 11.8 x 4.0 μm (9.6 x 4.2 - 13.2 x 3.6 μm), shape-index 2.9 (2.2 - 5.0), and females 13.5 x 4.5 μm (12.0 x 4.5 - 15.0 x 4.8 μm), shape-index 3.0 (2.2 - 3.8). Some larger meronts may slightly enlarge the erythrocyte, but most asexual stages and the mature gametocytes rarely do so. A second, P. tropiduri-like parasite encountered in K. calcarata possessed small rounded or fan-shaped meronts producing from 4-14 merozoites, and spherical to subspherical gametocytes of approximately 6.0 x 5.0 μm. The parasite was consistently polar in its position in the erythrocyte.

Published
2001
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3. Kidney sphaerosporosis with extrasporogonic stages in the blood in Baryancistrus sp. (Loricaridae) from Amazonian Brazil

Author

Paperna I. and Di Cave D.

Subjects
sphaerosporosis, Myxosporea, Baryancistrus, Loricaridae, Brazil, extrasporogony, blood, sporogony, glomerulus, Infectious and parasitic diseases, RC109-216
Abstract

Examined fish of the genus Baryancistrus (Loricaridae) from Rio Xingu in central amazonian Brazil were found infected with extrasporogonic stages of Sphaerospora sp. (Myxosporea) in the blood and sporogonic stages in the glomeruli with the resulting escape of the sporogony products into the renal tubules, apparently when the mesangial tissue in the Bowman's capsule collapsed. Spores were seen evacuating via the urinary tubules. Blood stages were initially 2.1 x 2.8 to 2.8 x 2.8 μm in size, and when fully differentiated reached 5.6 x 5.6 - 5.6 x 7.0 μm; in blood smears they were 11.2 x 8.4 to 14 x 8.4 μm. Bisporoblasts in the glomerular taft were 9.8 x 7.0 μm, premature spores were 5.6 x 4.2 - 5.6 μm.

Published
2001
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4. The life-cycle and ultrastructure of Sarcocystis ameivamastigodryasi n. sp., in the lizard Ameiva ameiva (Teiidae) and the snake Mastigodryas bifossatus (Colubridae)(1)

Author

Lainson R. and Paperna I.

Subjects
Sarcocystis ameivamastigodryasi n. sp., Ameiva ameiva, Kentropyx calcarata, lizards, Mastigodryas bifossatus, Mastigodryas boddaerti, Epicrates c. cenchria, Boa c. constrictor, snakes, transmission, Brazil, Infectious and parasitic diseases, RC109-216
Abstract

Sarcocysts in muscles of the teiid lizard Ameiva ameivafrom north Brazil were fed to the colubrid snake Mastigodryas bifossatus, the faeces of which had been shown to be devoid of coccidial oocysts or sporocysts. When necropsied 16 days later the snake was shown to have developed a massive intestinal infection of Sarcocystis. Mature sporocysts from another, naturally infected M. bifossatus were fed to juvenile specimens of A. ameiva in which no sarcocysts could be detected in tail muscle biopsies. When examined 30 and 47 days later they had very large numbers of sarcocysts in their tail and tongue muscles. The parasite is given the name of Sarcocystis ameivamastigodryasi n. sp. An ultrastructural study has been made of the sarcocyst and of the parasite's sporulation in the lamina propria of the snake: the latter provides details of the wall formation process in developing sporocysts. Attempts to infect a specimen of the boid Boa constrictor constrictor by feeding it with infected Ameivafailed, suggesting that sporocysts previously recorded in genera of the family Boidae may be those of a different species of Sarcocystis.

Published
2000
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5. The fine structure of the endogenous stages of Isospora hemidactyli carini, 1936 in the gecko Hemidactylus mabouia from North Brazil

Author

Paperna I and Lainson R

Subjects
Isospora hemidactyli, endogenous stages, ultrastructure, Hemidactylus mabouia, gecko, Brazil, Microbiology, QR1-502, Infectious and parasitic diseases, RC109-216
Abstract

The ultrastructure is described of the meronts, microgamonts and young oocyst stages of Isospora hemidactyli of the gecko Hemidactylus mabouia from Belém, PA, north Brazil. The endogenous stages all develop in the nucleus of the gut epithelial cells. The nucleus remains intact up to the latest stages of the parasite's development, but degenerates by the time the oocyst appears. Merogonic division appears to be asynchronous, and some of the differentiated merozoites contained more than one nucleus. Microgamonts conform in structure with those of other eimeriids. Some of the type 2 wall-forming bodies disintegrate into smaller globules and ground substance of lower density.

Published
2000

6. Quantitative genetic parameters for growth and wood properties in Eucalyptus 'urograndis' hybrid using near-infrared phenotyping and genome-wide SNP-based relationships

Author

Orzenil B. Silva-Junior, Bruno Marco de Lima, Shawn D. Mansfield, Carla Garcia, Dario Grattapaglia, Eduardo P. Cappa, BRUNO MARCO DE LIMA, USP, EDUARDO P. CAPPA, INSTITUTO NACIONAL DE TECNOLOGI´A AGROPECUARIA (INTA), ARGENTINA, ORZENIL BONFIM DA SILVA JUNIOR, Cenargen, CARLA GARCIA, INTERNATIONAL PAPER DO BRASIL ROD, SHAWN D. MANSFIELD, UNIVERSITY OF BRITISH COLUMBIA, CANADA, and DARIO GRATTAPAGLIA, Cenargen.

Subjects
0106 biological sciences, 0301 basic medicine, Heredity, Plant Science, 01 natural sciences, Lignin, Trees, Spectrum Analysis Techniques, NEAR-INFRARED PEHNOTYPING, Data Management, education.field_of_study, Eucalyptus, Multidisciplinary, Spectroscopy, Near-Infrared, Organic Compounds, Plant Anatomy, Eukaryota, near-Infrared Spectroscopy, Phylogenetic Analysis, Genomics, Plants, Wood, Phylogenetics, Polimorfismo de un Solo Nucleótido, Chemistry, Phenotypes, Phenotype, Genetic gain, Physical Sciences, Medicine, Brazil, Genome, Plant, Research Article, Genetic Research, Computer and Information Sciences, Genética Cuantitativa, Genotype, Science, Population, Infrared Spectroscopy, Quantitative trait locus, Biology, Research and Analysis Methods, Polymorphism, Single Nucleotide, Quantitative Genetics, 03 medical and health sciences, Quantitative Trait, Heritable, MOLECULAR RELATIONSHIP, Species Specificity, Genetic variation, Genetics, Evolutionary Systematics, PEDIGREE RELATIONSHIP, education, Cellulose, Fenotipos, Hybrid, Taxonomy, Evolutionary Biology, Models, Genetic, Directional selection, Organic Chemistry, Organisms, Chemical Compounds, Biology and Life Sciences, Heritability, purl.org/becyt/ford/4.5 [https], Plant Breeding, 030104 developmental biology, Evolutionary biology, Single Nucleotide Polymorphism, Tree breeding, Hybridization, Genetic, purl.org/becyt/ford/4 [https], 010606 plant biology & botany
Abstract

A thorough understanding of the heritability, genetic correlations and additive and non-additive variance components of tree growth and wood properties is a requisite for effective tree breeding. This knowledge is essential to maximize genetic gain, that is, the amount of increase in trait performance achieved annually through directional selection. Understanding the genetic attributes of traits targeted by breeding is also important to sustain decade-long genetic progress, that is, the progress made by increasing the average genetic value of the offspring as compared to that of the parental generation. In this study, we report quantitative genetic parameters for fifteen growth, wood chemical and physical traits for the world-famous Eucalyptus urograndis hybrid (E. grandis × E. urophylla). These traits directly impact the optimal use of wood for cellulose pulp, paper, and energy production. A population of 1,000 trees sampled in a progeny trial was phenotyped directly or following the development and use of near-infrared spectroscopy calibration models. Trees were genotyped with 33,398 SNPs and 24,001 DArT-seq genome-wide markers and genomic realized relationship matrices (GRM) were used for parameter estimation with an individual-tree additive-dominant mixed model. Wood chemical properties and wood density showed stronger genetic control than growth, cellulose and fiber traits. Additive effects are the main drivers of genetic variation for all traits, but dominance plays an equally or more important role for growth, singularly in this hybrid. GRM´s with >10,000 markers provided stable relationships estimates and more accurate parameters than pedigrees by capturing the full genetic relationships among individuals and disentangling the non-additive from the additive genetic component. Low correlations between growth and wood properties indicate that simultaneous selection for wood traits can be applied with minor effects on genetic gain for growth. Conversely, moderate to strong correlations between wood density and chemical traits exist, likely due to their interdependency on cell wall structure such that responses to selection will be connected for these traits. Our results illustrate the advantage of using genomewide marker data to inform tree breeding in general and have important consequences for operational breeding of eucalypt urograndis hybrids. Fil: de Lima, Bruno Marco. Universidade de Sao Paulo; Brasil. Ministerio da Agricultura Pecuaria e Abastecimento de Brasil. Empresa Brasileira de Pesquisa Agropecuaria; Brasil Fil: Cappa, Eduardo Pablo. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Recursos Biológicos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Silva Junior, Orzenil B.. Ministerio da Agricultura Pecuaria e Abastecimento de Brasil. Empresa Brasileira de Pesquisa Agropecuaria; Brasil. Universidade Católica de Brasília; Brasil Fil: Garcia, Carla. No especifíca; Fil: Mansfield, Shawn D.. University of British Columbia; Canadá Fil: Grattapaglia, Dario. Ministerio da Agricultura Pecuaria e Abastecimento de Brasil. Empresa Brasileira de Pesquisa Agropecuaria; Brasil. Universidade Católica de Brasília; Brasil

Published
2019

7. Temporal Patterns of Influenza A and B in Tropical and Temperate Countries: What Are the Lessons for Influenza Vaccination?

Author

Marietjie Venter, Juan Yang, Simona Puzelli, Antonino Bella, Joshua A. Mott, Rodrigo Fasce, Coulibaly Daouda, Jenny Lara, Hongjie Yu, Winston Andrade, Selim Badur, Cláudio Maierovitch Pessanha Henriques, François G. Schellevis, Jean-Michel Heraud, Akerke Ospanova, Sonam Wangchuk, Brechla Moreno, Herve A. Kadjo, Raymond T. P. Lin, Juan Manuel Rudi, Walquiria Aparecida Ferreira de Almeida, Gabriela Kusznierz, Joseph S. Bresee, Cheryl Cohen, Mai thi Quynh Le, Rhonda Owen, Maria Zambon, Maria Luisa Matute, Kunzang Dorji, Kate Pennington, Global Influenza B Study, Herman Kosasih, Nurhayati, Alla Mironenko, Ming Li, Angel Balmaseda, Alexey Clara, Alfredo Bruno, Richard Njouom, Phuong Vu Mai Hoang, Ana Paula Rodrigues, Celina de Lozano, Luzhao Feng, Olha Holubka, Amal Barakat, Lyazzat Kiyanbekova, Norosoa Harline Razanajatovo, Saverio Caini, Meral Akcay Ciblak, Raquel Guiomar, Richard Pebody, Leticia Castillo, Gideon O. Emukule, Liza Lopez, Doménica de Mora, Jeffery Cutter, Q. Sue Huang, Marie-Astrid Vernet, Abderrahman Bimohuen, John Paget, Lynnette Brammer, General practice, EMGO - Quality of care, Netherlands Institute for Health Services Research, Instituto de Salud Pública de Chile (ISP), Istanbul University, Ministry of Health [Nicaragua] (MINSA), Ministry of Health [Morocco], Istituto Superiore di Sanita [Rome], Centers for Disease Control and Prevention [Atlanta] (CDC), Centers for Disease Control and Prevention, Instituto Nacional de Investigación en Salud Pública [Guayaquil, Ecuador] (INSPI), Ministerio de Salud Publica y Asistencia Social [Guatemala] (MSPAS), US Centers for Disease Control, University of the Witwatersrand [Johannesburg] (WITS), Ministry of Health, Institut Pasteur de Côte d'Ivoire, Réseau International des Instituts Pasteur (RIIP), Ministerio de Salud de El Salvador (MINSAL), Ministry of Health [Bhoutan], US Centers for Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Instituto nacional de saude, Unité de Virologie [Antananarivo, Madagascar] (IPM), Institut Pasteur de Madagascar, Réseau International des Instituts Pasteur (RIIP)-Réseau International des Instituts Pasteur (RIIP), National Academy of Medical Sciences of Ukraine, Institute of Environmental Science and Research (ESR), Astana Center of Sanitary Epidemiology Expertise, US Naval Medical Research Unit n°2, Instituto Nacional de Enfermedades Respiratorias 'Dr. Emilio Coni', Ministry of Health [Costa Rica], National Institute of Hygiene and Epidemiology [Hanoi, Vietnam] (NIHE), Ministry of Health [Honduras] (SESAL), National Influenza Center, Centre Pasteur du Cameroun, Office of Health Protection, Woden, ACT, Australia (DHAISS), Public Health England [London], National Institute of Health, University of Pretoria [South Africa], The Global Influenza B Study is supported by an unrestricted research grant from Sanofi Pasteur. The study sponsor had no role in the design of the study, in the collection, analysis, and interpretation of data, in the writing of the report, and and in the decision to submit the paper for publication. The corresponding author had full access to all the data in the study and had final responsibility for the decision to submit for publication. The study sponsor had no access to the data in the study.

Subjects
Infecções Respiratórias, Influenza Viruses, Epidemiology, Gripe, Pathology and Laboratory Medicine, Geographical locations, 0302 clinical medicine, [SDV.MHEP.MI]Life Sciences [q-bio]/Human health and pathology/Infectious diseases, DRIVERS, Estados de Saúde, Public and Occupational Health, SUB-SAHARAN AFRICA, lcsh:Science, MESH: Influenza B virus, Northern Hemisphere, [SDV.MHEP.ME]Life Sciences [q-bio]/Human health and pathology/Emerging diseases, Geography, MESH: Influenza, Human, Vaccination, virus diseases, 3. Good health, Global Influenza B Study, MESH: Tropical Climate, [SDV.MP.VIR]Life Sciences [q-bio]/Microbiology and Parasitology/Virology, Science & Technology - Other Topics, Immunology, Disease Surveillance, SEASONAL INFLUENZA, Microbiology, Influenza Vaccin, 03 medical and health sciences, Influenza Vaccination, SURVEILLANCE, Humans, Microbial Pathogens, Retrospective Studies, MESH: Humans, Science & Technology, lcsh:R, Organisms, Correction, Influenza a, MESH: Retrospective Studies, [SDV.BBM.BM]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Molecular biology, medicine.disease, Virology, Influenza, MADAGASCAR, lcsh:Q, Preventive Medicine, People and places, Demography, RNA viruses, Viral Diseases, lcsh:Medicine, medicine.disease_cause, Tropical climate, Medicine and Health Sciences, Influenza A virus, 030212 general & internal medicine, Multidisciplinary, Medical microbiology, Vaccination and Immunization, Multidisciplinary Sciences, Infectious Diseases, Viruses, Human mortality from H5N1, Southern Hemisphere, Seasons, Pathogens, Brazil, Research Article, Infectious Disease Control, General Science & Technology, 030231 tropical medicine, MESH: Influenza A virus, Healthcare improvement science Radboud Institute for Health Sciences [Radboudumc 18], MD Multidisciplinary, Influenza, Human, Temperate climate, medicine, Tropical Climate, Biology and life sciences, business.industry, Other Research Radboud Institute for Health Sciences [Radboudumc 0], Viral pathogens, Tropics, MESH: Vaccination, South America, Seasonality, Earth sciences, Influenza B virus, Infectious Disease Surveillance, [SDV.SPEE]Life Sciences [q-bio]/Santé publique et épidémiologie, business, Geographic areas, MESH: Seasons, Orthomyxoviruses
Abstract

Erratum in - Correction: Temporal Patterns of Influenza A and B in Tropical and Temperate Countries: What Are the Lessons for Influenza Vaccination? PLoS One. 2016 May 2;11(5):e0155089. doi: 10.1371/journal.pone.0155089. Introduction: Determining the optimal time to vaccinate is important for influenza vaccination programmes. Here, we assessed the temporal characteristics of influenza epidemics in the Northern and Southern hemispheres and in the tropics, and discuss their implications for vaccination programmes. Methods: This was a retrospective analysis of surveillance data between 2000 and 2014 from the Global Influenza B Study database. The seasonal peak of influenza was defined as the week with the most reported cases (overall, A, and B) in the season. The duration of seasonal activity was assessed using the maximum proportion of influenza cases during three consecutive months and the minimum number of months with 80% of cases in the season. We also assessed whether co-circulation of A and B virus types affected the duration of influenza epidemics. Results: 212 influenza seasons and 571,907 cases were included from 30 countries. In tropical countries, the seasonal influenza activity lasted longer and the peaks of influenza A and B coincided less frequently than in temperate countries. Temporal characteristics of influenza epidemics were heterogeneous in the tropics, with distinct seasonal epidemics observed only in some countries. Seasons with co-circulation of influenza A and B were longer than influenza A seasons, especially in the tropics. Discussion: Our findings show that influenza seasonality is less well defined in the tropics than in temperate regions. This has important implications for vaccination programmes in these countries. High-quality influenza surveillance systems are needed in the tropics to enable decisions about when to vaccinate. The Global Influenza B Study is supported by an unrestricted research grant from Sanofi Pasteur. info:eu-repo/semantics/publishedVersion

Published
2016

8. Evaluation of ALOS/PALSAR L-Band data for the estimation of Eucalyptus plantations aboveground biomass in Brazil

Author

Yann Nouvellon, Cristiane Lemos, Rodrigo Hakamada, Kenji Ose, Jean-Stéphane Bailly, Guerric Le Maire, Mehrez Zribi, Nicolas Baghdadi, Territoires, Environnement, Télédétection et Information Spatiale (UMR TETIS), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-AgroParisTech-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Institut National de la Recherche Agronomique (INRA)-Institut de Recherche pour le Développement (IRD)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Laboratoire d'étude des Interactions Sol - Agrosystème - Hydrosystème (UMR LISAH), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut de Recherche pour le Développement (IRD [ Madagascar])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Departamento de Ciências Florestais, University of São Paulo (USP), Centre d'études spatiales de la biosphère (CESBIO), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), International Paper do Brasil, Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Universidade de São Paulo = University of São Paulo (USP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), and Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Atmospheric Science, Biomass, SILVICULTURA, law.invention, Âge, [SDV.SA.SF]Life Sciences [q-bio]/Agricultural sciences/Silviculture, forestry, law, K01 - Foresterie - Considérations générales, Biomasse, Radar, Eucalyptus, [SDE.IE]Environmental Sciences/Environmental Engineering, U10 - Informatique, mathématiques et statistiques, Aboveground biomass, Vegetation, fast-growing plantations, Plantation forestière, Imagerie, short-rotation plantations, Brazil, Synthetic aperture radar, Eucalyptus grandis, L band, Télédétection, Production forestière, Radar imaging, Computers in Earth Sciences, Croissance, Hydrology, Méthode statistique, Rotation de coupe, L-band ALOS/PALSAR, Sowing, Forestry, 15. Life on land, Eucalyptus urophylla, K10 - Production forestière, Environmental science, Dendrométrie, U30 - Méthodes de recherche
Abstract

[Departement_IRSTEA]Territoires [TR1_IRSTEA]SYNERGIE [Axe_IRSTEA]TETIS-ATTOS; International audience; The Phased Array L-band Synthetic Aperture Radar (PALSAR-1) has provided very useful images dataset for several applications such as forestry. L-band radar measurements have been widely used but with somewhat contradictory conclusions on the potential of this radar wavelength to estimate the aboveground biomass. The first objective of this study was to analyze the L-band SAR backscatter sensitivity to forest biomass for Eucalyptus plantations. The results showed that the radar signal is highly dependent on biomass only for values lower than 50 t/ha, which corresponds to plantations of approximately three years of age. Next, Random Forest regressions were performed to evaluate the potential of PALSAR data to predict the Eucalyptus biomass. Regressions were constructed to link the biomass to both radar signal and age of plantations. Results showed that the age was the variable that best explained the biomass followed by the PALSAR HV polarized signal. For biomasses lower than 50 t/ha, HV signal and plantation age were found to have the same level of importance in predicting biomass. For biomasses higher than 50 t/ha, plantation age was the main variable in the random forest models. The use of PALSAR signal alone did not correctly predict the biomass of Eucalyptus plantations (R² lower than 0.5 and RMSE higher than 46.7 t/ha). The use of plantation age in addition to the PALSAR signal improved slightly the prediction results (R² increased from 0.88 to 0.92 and RMSE decreased from 22.7 to 18.9 t/ha). PALSAR imagery does not allow a direct estimation of the planting date of Eucalyptus stands but can follow efficiently the occurrence of clear-cuts if images are acquired sequentially, therefore allowing a rough estimate of the following plantation date because a stand of Eucalyptus is generally re-planted 2 to 4 months after cutting. With a time series of radar images, it could be therefore possible to estimate the plantation age, and therefore improving the estimates of plantation biomass.

Published
2015