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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, vol 78 n° 3 (September 2021)  

Public [article]  inAnnals of Forest Science > 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]

Multi-actor perspectives on afforestation and reforestation strategies in Central Europe under climate change / Reneema Hazarika in Annals of Forest Science, vol 78 n° 3 (September 2021)  

Public [article]  inAnnals of Forest Science > vol 78 n° 3 (September 2021) . - n° 60 Titre : Multi-actor perspectives on afforestation and reforestation strategies in Central Europe under climate change Type de document : Article/Communication Auteurs : Reneema Hazarika, Auteur ; Andreas Bolte, Auteur ; Dagmar Bednarova, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : n° 60 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] afforestation [Termes IGN] changement climatique [Termes IGN] diversité génétique [Termes IGN] Europe centrale [Termes IGN] reboisement [Vedettes matières IGN] Végétation et changement climatique Résumé : (auteur) Key message: Understanding forest genetic diversity and national legislation on trade and utilization of forest reproductive material (FRM) are key aspects for management and adapting forests to climate change. Despite concerns about the negative effects of climate change on forests, awareness of the role of genetic diversity in climate change adaptation is limited. Context: Adaptive forest management strategies such as afforestation and reforestation depend on the selection of appropriate FRM and their knowledge among the relevant stakeholders. Aims: To analyze the perceptions among the forest, conservation, and nursery managers of six Central European countries on awareness of genetic diversity and practical and legislative issues of afforestation and reforestation in climate change. Methods: A survey was conducted with structured questionnaires. Results: Around 80% of the respondents believe in climate change. Local FRM is preferred for reforestation. Although 80% of the conservation and forest managers perceive the importance of forest genetic diversity, almost half of them feel unaware of it. The majority of respondents believe that national and European legislation on seed transfer is not adapted to climate change. Conclusion: Inadequacy in the awareness of genetic diversity and policies on FRM is likely to influence forest adaptation to climate change in Europe. Numéro de notice : A2021-543 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s13595-021-01044-5 Date de publication en ligne : 05/07/2021 En ligne : https://doi.org/10.1007/s13595-021-01044-5 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98040 [article]

Using electrical resistivity tomography to detect wetwood and estimate moisture content in silver fir (Abies alba Mill.) / Ludovic Martin in Annals of Forest Science, vol 78 n° 3 (September 2021)  

Public [article]  inAnnals of Forest Science > vol 78 n° 3 (September 2021) . - n° 65 Titre : Using electrical resistivity tomography to detect wetwood and estimate moisture content in silver fir (Abies alba Mill.) Type de document : Article/Communication Auteurs : Ludovic Martin, Auteur ; Sébastien Cochard, Auteur ; Stefan Mayr, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : n° 65 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection [Termes IGN] Abies alba [Termes IGN] bois sur pied [Termes IGN] filière bois - forêt [Termes IGN] forêt humide [Termes IGN] humidité du sol [Termes IGN] Massif central (France) [Termes IGN] résistivité [Termes IGN] teneur en eau de la végétation [Termes IGN] tomographie Résumé : (auteur) Key message : Using several experimental approaches, we have demonstrated that electrical resistivity tomography (ERT) is a reliable nondestructive tool for estimating the moisture content of heartwood in situ. ERT measurements show that water pockets in heartwood (wetwood) are present in a large majority (90%) of silver fir ( Abies alba Mill.) trunks. Context : For wood professionals, the presence of wetwood in wood logs leads to an increase in costs, especially during the drying process. Assessing these internal properties in situ with a nondestructive method will provide reliable information for improved management of respective forests. Aims : The objective of this study was to evaluate the efficiency of the electrical resistivity tomography (ERT) tool to detect wetwood in standing trees and to estimate the mean moisture content (MC) of silver fir trunks. Methods : The study was carried out in 3 forests located in the region “Massif Central” in France. We selected 58 silver fir trees, visually healthy and without visible default. Each tree has been subject to regular ERT measurements for more than a year. At the same time, one to three cores were taken from each tree in order to measure the actual MC of the wood. Results : 90% of the silver fir trees showed the presence of wetwood in their heartwood. Our results showed a significant correlation between the mean heartwood MC measured on cores and the mean electrical resistivity (ER) obtained with ERT. Conclusion : The presence of wetwood occurs in a high proportion of the silver fir trees studied, and (ii) ERT can be used to estimate the average MC of the heartwood of standing trees. However, the data provided by ERT vary seasonally and do not allow the precise location of wetwood. Numéro de notice : A2021-622 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s13595-021-01078-9 Date de publication en ligne : 27/07/2021 En ligne : https://doi.org/10.1007/s13595-021-01078-9 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98244 [article]