Résumé

Organized forestry in Brazil began in the late 1960s, stimulated by a government policy which subsidized afforestation programs from 1967 to 1989 to develop an internationally-competitive wood-based industry, managed by the private sector. Currently, planted forests in Brazil total about 6.9 million ha, from which 4.9 million ha is planted with eucalypt (around 25% of world plantation), 1.6 million ha with pine, and 0.42 M ha with other species. Roundwood consumption of forest plantations totaled 170.1 million m3 in 2011, eucalypt plantation accounted for 80.6% of this total. Most eucalypt plantations are managed in short rotations (6-8 years) and are established in regions with water, nutritional and frost stresses of low to high degrees. The mean annual increment is 40 m3 ha?1 year?1 roundwood, ranging from 25 to 60 m3 ha?1 year?1 depending on the level of environmental stress. Improving natural resources use efficiency by breeding and matching genotypes to sites and using appropriate site management practices is a key challenge to sustain or increase productivity. The wide range of eucalypt species and hybrids with different climatic and edaphic suitability associated with the easy propagation by seeds and cloning allow the adaptation of plantations to various tropical and subtropical regions in Brazil. The possibility of using eucalypt wood in a range of purposes has led large and small enterprises to establish eucalypt forests for multiple uses. The desirable characteristics in association with the accumulated knowledge on eucalypt silviculture encourage the use of this genus in most plantations. The most important factors in the selective process for a genotype are wood characteristics, productivity level, susceptibility to pests and diseases, drought tolerance, especially in tropical regions (frost free), and frost tolerance in subtropical regions (mostly without water deficit). In regions with pronounced seasonality and moderate to long drought periods, the planting of hybrid genotypes predominates, propagated by cloning. Under subtropical conditions, the planting of single species predominates, propagated by seed. Clonal plantations with interspecific hybrids have been fundamental for eucalypt adaptation in regions under water and nutritional stresses. Given the rapid advances in eucalypt breeding, regarding adaptation to water stress and resistance to diseases and pests, and the adoption of clonal propagation techniques, genotypes are rapidly becoming obsolete and are replaced by more productive ones after harvesting. Thus, the replanting of crops has become a common procedure after the second half of the 1990s in Brazil. This paper describes the basic requirements for integrating genetic and silvicultural strategies to minimize abiotic and biotic constraints in eucalypt plantations. (Résumé d'auteur)


Auteurs, date et publication :

Auteurs Jose Leonardo De Moraes Gonçalves , Clayton Alcarde Alvares , Antonio Rioyei Higa , James Stahl , Silvio Frosini De Barros Ferraz , Walter De Paula Lima , Pedro Henrique Santin Brancalion , Ayeska Hubner , Jean-Pierre Bouillet , Jean-Paul Laclau , Daniel Epron , Yann Nouvellon

Publication : Forest Ecology and Management

Date : 2025

Volume : 301

Pages : 6-27


Catégorie(s)

#CIRAD #FORET Itatinga #INRAE

Résumé

Une infrastructure nationale pour l'étude des écosystèmes continentaux permettant l'étude du cycle du carbone. Présenté lors du séminaire de démarrage du PEPR exploratoire FairCarboN en octobre 2023.


Auteurs, date et publication :

Auteurs Alyssa Clavreul , Jean-François Le Galliard , Laurence Denaix

Date : 2023


Catégorie(s)

#CNRS #Coordination AnaEE #INRAE

Auteurs, date et publication :

Auteurs Abad Chabbi , Henry William Loescher , Mari R Tye , David Hudnut , A. Chabbi , Henry William Loescher

Date : 2025

Pages : 534


Catégorie(s)

#ACBB #ACBB Lusignan #INRAE

Résumé

Storage of selenium and iodine can greatly vary between forest ecosystems, but the influence of tree species on partitioning and recycling of those elements remains elusive. In this study, contents of Se and I were measured in tree compartments, litterfall, humus, and soil horizons in monospecific stands of Douglas fir, pine, spruce, beech, and oak under identical climatic and edaphic conditions. The cycle of each element was characterized in terms of stocks and fluxes. Lowest concentrations were in wood (Se: 8–13 μg kg−1; I: <16.5 μg kg−1). Senescing organs had higher Se and I content, than the living parts of trees due to direct exposure to atmospheric deposition, with some variation between coniferous and deciduous trees. For all stands, low amounts of Se and I were involved in biological cycle as reflected by low root uptake. In humus, the enrichment of elements greatly increased with the stage of organic matter (OM) degradation with average factors of 10 and 20 for Se and I. OM degradation and element persistence in humus was influenced by tree species. Deciduous trees, with low biomass, and fast degradation of OM stored less Se and I in humus compared to fir and spruce with high humus biomass. Interestingly, tree species did not affect soil reserves of Se and I. Concentration ranges were 331–690 μg Se kg−1 and 4.3–14.5 mg I kg−1. However, the divergent vertical profiles of the elements in the soil column indicated greater mobility of I. Selenium concentrations regularly decreased with depth in correlation with OM and Fe oxides content. For iodine, the maximum iodine concentration at a soil depth of 15 to 35 cm was caused by a parallel precipitation/sorption behavior of aluminium and organic iodine dissolved in the topsoil.


Auteurs, date et publication :

Auteurs Paulina Pisarek , Maïté Bueno , Yves Thiry , Arnaud Legout , Hervé Gallard , Isabelle Le Hécho

Publication : Science of The Total Environment

Date : 2025

Volume : 809

Pages : 151174


Catégorie(s)

#FORET Breuil #INRAE

Résumé

Many natural terrestrial ecosystems, agroforestry systems, and, increasingly, forest plantations, are made of a mixture of species and display significant structural heterogeneity. Yet most carbon-based biophysical models are limited to homogeneous, monospecific canopies.


Auteurs, date et publication :

Auteurs Guillaume Simioni , Guillaume Marie , Roland Huc

Publication : Ecological Modelling

Date : 2025

Volume : 328

Pages : 119-135


Catégorie(s)

#FORET FontBlanche #INRAE

Résumé

The greatest known global response of lakes to climate change has been an increase in water temperatures. The responses of many lake fishes to warming water temperatures are projected to be inadequate to counter the speed and magnitude of climate change. We experimentally evaluated the responses of embryos from a group of cold, stenothermic fishes (Salmonidae Coregoninae) to increased incubation temperatures. Study groups included cisco (Coregonus artedi) from lakes Superior and Ontario (USA), and vendace (C. albula) and European whitefish (C. lavaretus) from Lake Southern Konnevesi (Finland). Embryos from artificial crossings were incubated at water temperatures of 2.0, 4.5, 7.0, and 9.0°C, and their responses were quantified for developmental and morphological traits. Embryo survival, incubation period, and length-at-hatch were inversely related to incubation temperature whereas yolk-sac volume increased with incubation temperature within study groups. However, varying magnitudes of responses among study groups suggested differential levels of developmental plasticity to climate change. Differential levels of parental effects indicate genetic diversity may enable all study groups to adapt to cope with some degree of changing environmental conditions. Our results suggest that the coregonines sampled within and among systems may have a wide range of embryo responses to warming incubation conditions.


Auteurs, date et publication :

Auteurs Taylor R. Stewart , Mikko Mäkinen , Chloé Goulon , Jean Guillard , Timo J. Marjomäki , Emilien Lasne , Juha Karjalainen , Jason D. Stockwell

Publication : Hydrobiologia

Date : 2021

Volume : 848

Issue : 18

Pages : 4363-4385


Catégorie(s)

#INRAE #OLA

Résumé

Une infrastructure nationale d'Analyse et d'Expérimentation pour comprendre,  prédire et gérer le fonctionnement des écosystèmes continentaux.


Auteurs, date et publication :

Auteurs Alyssa Clavreul , Laurence Denaix

Date : 2023


Catégorie(s)

#Coordination AnaEE #INRAE

Résumé

Une infrastructure nationale au service de l'écologie aquatique. Présenté pour les Journées du PEPR One Water en juillet 2023.


Auteurs, date et publication :

Auteurs Alyssa Clavreul , Laurence Denaix , Jean-François Le Galliard

Date : 2023


Catégorie(s)

#CNRS #Coordination AnaEE #INRAE

Résumé

The effects of mixed stands on biodiversity are increasingly being studied since they are supposed to offer higher habitat heterogeneity. Nevertheless, for tree-associated diversity, including epiphytes and terricolous species near tree trunks, few studies exist, and still fewer compare mixed stands with each corresponding pure tree species stand. We evaluated and quantified the influence of forest composition on tree-associated bryophyte diversity (species richness, abundance, composition) in mixed and pure oak-pine stands in a French lowland forest. The main explanatory variables for bryophyte diversity at tree-level were the identity of the phorophyte tree species and the mixture type (pure versus mixed). At the plot level, the main explanatory variable was the stand type (pure oak, pure pine and mixed). We also explored the role of other variables including the chemistry of the bryophyte substrates (soil, bark) and water supply (stemflow, throughfall), as well as stand abundance variables (basal area, interfering plant cover). We analyzed data with Generalized Linear Models under Bayesian statistics, to take into account the spatial autocorrelation between plots and any under- or over-dispersion of our data. At the tree-level, bryophyte richness and abundance were higher on oak than on pine. Pine bryophyte richness was higher in mixed compared to pure stands, whereas for oak, mixed stands did not enhance bryophyte richness. At the plot level, mixed stands hosted bryophyte communities of similar richness to those in pure oak stands, whereas pure pine stands were clearly poorer. Our exploratory models suggested strong effects of water supply chemistry (stemflow and throughfall pH or conductivity) and basal area; the latter had a strong quadratic effect on epiphytic richness at the plot level. In terms of composition, three species were more likely to be found on pine phorophytes, seven species clearly occurred more frequently on oaks. Some species were more likely to be associated to pine in mixed than in pure stands, and one species was found more often under pines in pure stands. Therefore, bryophyte diversity at the landscape level should benefit from the simultaneous presence of the three stand composition types – pure oak, pure pine and mixed stands.


Auteurs, date et publication :

Auteurs Marion Gosselin , Deki Fourcin , Yann Dumas , Frédéric Gosselin , Nathalie Korboulewsky , Maude Toïgo , Patrick Vallet

Publication : Forest Ecology and Management

Date : 2017

Volume : 406

Pages : 318-329


Catégorie(s)

#FORET OPTMix #INRAE

Résumé

Recent studies showed a positive tree response to Na addition in K-depleted tropical soils. Our study aimed to gain insight into the effects of K and Na fertilizations on leaf area components for a widely planted tree species.


Auteurs, date et publication :

Auteurs P. Battie-Laclau , M.-C. Piccolo , Bruna C. Arenque , C. Beri , L. Mietton , M.-R.-A. Muniz , L. Jordan-Meille , M.-S. Buckeridge , Y. Nouvellon , J. Ranger , J.-P. Bouillet

Publication : Plant and Soil

Date : 2025

Volume : 371

Issue : 1

Pages : 19-35


Catégorie(s)

#CIRAD #FORET Itatinga #INRAE