Centre dedocumentation
scientifique

Variation in downed deadwood density, biomass, and moisture during decomposition in a natural temperate forest / Tomas Přívětivý in Forests, vol 12 n° 10 (October 2021)  

Public [article]  inForests > vol 12 n° 10 (October 2021) Titre : Variation in downed deadwood density, biomass, and moisture during decomposition in a natural temperate forest Type de document : Article/Communication Auteurs : Tomas Přívětivý, Auteur ; Pavel Šamonil, Auteur Année de publication : 2021 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] Abies alba [Termes IGN] biodiversité végétale [Termes IGN] biomasse forestière [Termes IGN] bois mort [Termes IGN] Europe centrale [Termes IGN] Fagus sylvatica [Termes IGN] forêt ancienne [Termes IGN] forêt tempérée [Termes IGN] montagne [Termes IGN] Picea abies [Termes IGN] teneur en eau de la végétation [Vedettes matières IGN] Foresterie Résumé : (auteur) Deadwood is a resource of water, nutrients, and carbon, as well as an important driving factor of spatial pedocomplexity and hillslope processes in forested landscapes. The applicability of existing relevant studies in mountain forests in Central Europe is limited by the low number of data, absence of precise dating, and short time periods studied. Here, we aimed to assess the decomposition pathway in terms of changes and variability in the physical characteristics of deadwood (wood density, biomass, and moisture) during the decomposition process, and to describe differences in decomposition rate. The research was carried out in the Žofínský Primeval Forest, one of the oldest forest reserves in Europe. Samples were taken from sapwood of downed logs of the three main tree species: Fagus sylvatica L., Abies alba Mill., and Picea abies (L.) Karst. The time since the death of each downed log was obtained using tree censuses repeated since 1975 and dendrochronology. The maximal time since the death of a log was species-specific, and ranged from 61–76 years. The rate of change (slope) of moisture content along the time since death in a linear regression model was the highest for F. sylvatica (b = 3.94) compared to A. alba (b = 2.21) and P. abies (b = 1.93). An exponential model showing the dependence of biomass loss on time since death revealed that F. sylvatica stems with a diameter of 50–90 cm had the shortest decomposition rate—51 years—followed by P. abies (71 years) and A. alba (72 years). Our findings can be used in geochemical models of element cycles in temperate old-growth forests, the prediction of deadwood dynamics and changes in related biodiversity, and in refining management recommendations. Numéro de notice : A2021-619 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.3390/f12101352 En ligne : https://doi.org/10.3390/f12101352 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98629 [article]

Assessing the land expectation value of even-aged vs coppice-with-standards stand management and long-term effects of whole-tree harvesting on forest productivity and profitability / Abdelwahad Bessaad in Annals of Forest Science [en ligne], vol 78 n° 3 (September 2021)  

Public [article]  inAnnals of Forest Science [en ligne] > vol 78 n° 3 (September 2021) . - n° 57 Titre : Assessing the land expectation value of even-aged vs coppice-with-standards stand management and long-term effects of whole-tree harvesting on forest productivity and profitability Type de document : Article/Communication Auteurs : Abdelwahad Bessaad, Auteur ; Jean-Philippe Terreaux, Auteur ; Nathalie Korboulewsky, Auteur Année de publication : 2021 Article en page(s) : n° 57 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] Castanea sativa [Termes IGN] changement climatique [Termes IGN] croissance des arbres [Termes IGN] gestion forestière durable [Termes IGN] marché du bois [Termes IGN] mortalité [Termes IGN] productivité [Termes IGN] Quercus sessiliflora [Termes IGN] récolte de bois [Vedettes matières IGN] Foresterie Résumé : (auteur) Key message: Whole-tree harvesting makes forests more profitable than conventional harvest as long as the impact on tree growth remains under 2.3% for even-aged oak ( Quercus petraea (Matt.) Liebl.) and 3.4% for sweet chestnut ( Castanea sativa Mill.) coppice with oak standards. Coppice-with-standards may have potential to be more profitable than even-aged oak in case of 50% rise in fuelwood prices with 10% decrease in timber prices. Context: Making the shift to renewable energy sources requires increasing biomass removal from the forest in a sustainable way. Today, the most common practice for forest biomass extraction is whole-tree harvesting rather than conventional harvest in which only stems are harvested or sometimes branches larger than 7 cm in diameter. However, intensive biomass harvesting can certainly increase economic profitability but it could affect long-term forest productivity because more nutrients are exported from sites. Aims: We explored the land expectation value of even-aged oak (Quercus petraea (Matt.) Liebl.) and sweet chestnut (Castanea sativa Mill.) coppice with oak standards under different discount rates and wood prices scenarios, tree mortality triggered by climate variation as well as the effects of a decrease in forest productivity due to whole-tree harvesting on the land expectation value (LEV). Methods: We modeled two plausible harvesting scenarios for both stands and assessed their LEV. We first analyzed the sensitivity of the valuation results to discount rate, wood prices changes, and increased tree mortality rates. Second, we compared conventional harvest to whole-tree harvesting in which removing the fine wood implies a decrease in tree growth over the long term (between 1 and 10%). Results: In the current economic situation, the LEV of even-aged oak is higher than coppice-with-standards but this situation could be reversed in case of rising energy prices and lower timber prices in the future. The variation of the discount rate has a significant impact on the LEV but 3% seems to be adequate for European forests. A gradual increase in annual tree mortality rate of 0.6 and 0.9% along even-aged and CWS rotation, respectively, reduced the LEV by half, while increased mortality with constant rates along the rotations had more negative effect on the LEV than gradual increases: 0.4–0.5% increases in mortality rates reduced both LEV’s by half. Whole-tree harvesting is able to improve the LEV for both stands by 36 to 64% compared to conventional harvest; but this improvement of LEV only lasts as long as the impact on tree growth remains under 2.3 and 3.4%, respectively, for even-aged oak stand and coppice-with-standards. Conclusion: Whole-tree harvesting system increases forest profitability as long as the sustainability guidelines for biomass harvesting are respected. With the increased demand for fuelwood, the coppice-with-standards regime may become financially attractive once again and fulfill a multitude of forest owner objectives with a wide range of additional options. Numéro de notice : A2021-519 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s13595-021-01071-2 Date de publication en ligne : 21/06/2021 En ligne : https://doi.org/10.1007/s13595-021-01071-2 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97943 [article]

Models for integrating and identifying the effect of senescence on individual tree survival probability for Norway spruce / Jouni Siipilehto in Silva fennica, vol 55 n° 2 (April 2021)  

Public [article]  inSilva fennica > vol 55 n° 2 (April 2021) . - n° 10496 Titre : Models for integrating and identifying the effect of senescence on individual tree survival probability for Norway spruce Type de document : Article/Communication Auteurs : Jouni Siipilehto, Auteur ; Harri Mäkinen, Auteur ; Kjell Andreassen, Auteur ; Mikko Peltoniemi, Auteur Année de publication : 2021 Article en page(s) : n° 10496 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] âge du peuplement forestier [Termes IGN] analyse comparative [Termes IGN] dynamique de la végétation [Termes IGN] Finlande [Termes IGN] modèle de croissance végétale [Termes IGN] modélisation de la forêt [Termes IGN] mortalité [Termes IGN] Norvège [Termes IGN] Picea abies [Vedettes matières IGN] Foresterie Résumé : (auteur) Ageing and competition reduce trees’ ability to capture resources, which predisposes them to death. In this study, the effect of senescence on the survival probability of Norway spruce (Picea abies (L.) Karst.) was analysed by fitting alternative survival probability models. Different model formulations were compared in the dataset, which comprised managed and unmanaged plots in long-term forest experiments in Finland and Norway, as well as old-growth stands in Finland. Stand total age ranged from 19 to 290 years. Two models were formulated without an age variable, such that the negative coefficient for the squared stem diameter described a decreasing survival probability for the largest trees. One of the models included stand age as a separate independent variable, and three models included an interaction term between stem diameter and stand age. According to the model including stand age and its interaction with stem diameter, the survival probability curves could intersect each other in stands with a similar structure but a different mean age. Models that did not include stand age underestimated the survival rate of the largest trees in the managed stands and overestimated their survival rate in the old-growth stands. Models that included stand age produced more plausible predictions, especially for the largest trees. The results supported the hypothesis that the stand age and senescence of trees decreases the survival probability of trees, and that the ageing effect improves survival probability models for Norway spruce. Numéro de notice : A2021-737 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.14214/sf.10496 Date de publication en ligne : 10/06/2021 En ligne : https://doi.org/10.14214/sf.10496 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98696 [article]

Relative influence of stand and site factors on aboveground live-tree carbon sequestration and mortality in managed and unmanaged forests / Christel C. Kern in Forest ecology and management, vol 493 (1st August 2021)  

Public [article]  inForest ecology and management > vol 493 (1st August 2021) . - n° 119266 Titre : Relative influence of stand and site factors on aboveground live-tree carbon sequestration and mortality in managed and unmanaged forests Type de document : Article/Communication Auteurs : Christel C. Kern, Auteur ; Laura S. Kenefic, Auteur ; Christian Kuehne, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : n° 119266 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] arbre mort [Termes IGN] climat [Termes IGN] Etats-Unis [Termes IGN] forêt inéquienne [Termes IGN] gestion forestière [Termes IGN] puits de carbone [Termes IGN] structure d'un peuplement forestier [Termes IGN] teneur en carbone [Vedettes matières IGN] Foresterie Résumé : (auteur) We compiled data from several independent, long-term silvicultural studies on USDA Forest Service experimental forests across a latitudinal gradient in the northeastern and north-central U.S.A. to evaluate factors influencing aboveground live-tree carbon sequestration and mortality. Data represent five sites with more than 70,000 repeated tree records spanning eight decades, five ecoregions, and a range of stand conditions. We used these data to test the relative influence of factors such as climate, treatment history (uneven-aged or no management), species composition, and stand structural conditions on aboveground live-tree carbon sequestration and mortality in repeatedly measured trees. Relative to no management, we found that uneven-aged management tended to have a positive effect on carbon sequestration at low stocking levels and in areas of favorable climate (expressed as a combination of growing season precipitation and annual growing degree days > 5 °C). In addition, losses of carbon from the aboveground live-tree pool due to tree mortality were lower in managed than unmanaged stands. These findings suggest that there may be conditions at which rate of sequestration in living trees is higher in stands managed with uneven-aged silviculture than in unmanaged stands, and that this benefit is greatest where climate is favorable. Numéro de notice : A2021-458 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1016/j.foreco.2021.119266 Date de publication en ligne : 28/04/2021 En ligne : https://doi.org/10.1016/j.foreco.2021.119266 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97920 [article]

Dynamique contrastée de la compaction d’un ferralsol après une défriche mécanisée alternative en Guyane française / Xavier Guerrini in Bois et forêts des tropiques, n° 348 ([06/07/2021])  

Public [article]  inBois et forêts des tropiques > n° 348 [06/07/2021] Titre : Dynamique contrastée de la compaction d’un ferralsol après une défriche mécanisée alternative en Guyane française Type de document : Article/Communication Auteurs : Xavier Guerrini, Auteur ; Vincent Freycon, Auteur ; Alexandre de Haldat du Lys, Auteur ; Eric Nicolini, Auteur Année de publication : 2021 Note générale : bibliographie Langues : Français (fre) Descripteur : [Termes IGN] défrichement [Termes IGN] Guyane (département français) [Termes IGN] légumineuse fourragère [Termes IGN] sol forestier [Termes IGN] surveillance géologique [Vedettes matières IGN] Foresterie Mots-clés libres : Stylosanthes guianensis Résumé : (auteur) Le changement d’usage des terres et l’impact de l’anthropisation sur les milieux forestiers tropicaux sont en progression constante sous les tropiques et en Guyane française. Ces changements sont souvent accompagnés de défriches mécanisées qui favorisent la compaction du sol. Notre objectif était de suivre l’évolution de la compaction du sol d’une parcelle de forêt naturelle exploitée (7 ha) soumise à une défriche mécanisée alternative (itinéraire « chop and mulch », couvert herbacé de Stylosanthes guianensis), puis replantée de quatre espèces forestières commerciales. Sur cet espace présentant finalement diverses couvertures de sol (sol nu, mulch, couvert herbacé), nous avons mesuré la densité apparente jusqu’à 30 cm de profondeur et effectué le test d’infiltration simplifié de Beerkan lors de trois campagnes : avant, juste après et neuf mois après la défriche. Avant la défriche, les sols avaient une très bonne capacité d’infiltration (111 cm/h), étaient peu denses à 0-5 cm de profondeur (0,88) et denses à 5-30 cm (1,19 à 1,40). Juste après la défriche, les sols avaient une capacité d’infiltration très réduite (2 cm/h) et leur couche de surface avait été fortement compactée (1,28) contrairement aux couches plus profondes (1,41 à 1,49). Neuf mois après la défriche, les sols avaient retrouvé une très bonne capacité d’infiltration (149 cm/h), particulièrement sous le couvert herbacé de S. guianensis, et leur couche de surface avait retrouvé une densité proche de l’état initial (1,01), contrairement aux couches plus profondes (1,46 à 1,58). De futures recherches sont nécessaires pour expliquer le retour rapide à l’état initial de la couche de surface et estimer la contribution relative de la macrofaune du sol, des racines et de la fissuration. Numéro de notice : A2021-618 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.19182/bft2021.348.a36751 En ligne : https://doi.org/10.19182/bft2021.348.a36751 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98626 [article]

The presence of shade-intolerant conifers facilitates the regeneration of Quercus petraea in mixed stands / Jeremy Borderieux in Forest ecology and management, vol 491 (1st July 2021)  

Permalink

Towards silviculture guidelines to produce large-sized silver birch (betula pendula roth) logs in Western Europe / Héloïse Dubois in Forests, vol 12 n° 5 (May 2021)  

Permalink

Chemical interaction between Quercus pubescens and its companion species is not emphasized under drought stress / H. Hashoum in European Journal of Forest Research, vol 140 n° 2 (April 2021)  

Permalink

Keeping mixtures of Norway spruce and birch in production forests: insights from survey data / Emma Hölmstrom in Scandinavian journal of forest research, vol 36 n° 2-3 ([01/03/2021])  

Permalink

The Salem simulator version 2.0: a tool for predicting the productivity of pure and mixed stands and simulating management operations / Raphaël Aussenac in Open Research Europe, vol 2021 ([01/03/2021])  

Permalink

An infrastructure perspective for enhancing multi-functionality of forests: A conceptual modeling approach / Mojtaba Houballah in Earth' future, vol 9 n° 1 (January 2021)  

Permalink

Conference Proceedings 8th Forest Europe Ministerial Conference, Bratislava, 14 - 15 April 2021 / Forest Europe (2021)  

Permalink

Stakeholder perceptions, management and impacts of forestry conflicts in southern Sweden / Rikard Jakobsson in Scandinavian journal of forest research, vol 36 n° 1 (January 2021)  

Permalink

State of Europe's forests 2020 / Forest Europe (2021)  

Permalink

A web-based integrated modeling and simulation method for forest growth research / Zaiyang Ma in Earth and space science, vol 6 n° 11 (November 2019)  

Permalink