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991.
David Da Silva Philippe Balandier Frédéric Boudon André Marquier Christophe Godin 《Annals of Forest Science》2012,69(2):181-193
• Context
Light availability in forest understory is essential for many processes; it is, therefore, a valuable information regarding forest management. However, its estimation is often difficult and direct measurements are tedious. Models can be used to compute understory light, but they often require a lot of field data to accurately predict light distribution, particularly in the case of heterogeneous canopies. 相似文献992.
Rasoul Yousefpour Jette Bredahl Jacobsen Bo Jellesmark Thorsen Henrik Meilby Marc Hanewinkel Karoline Oehler 《Annals of Forest Science》2012,69(1):1-15
• Context
This review paper provides an overview of approaches to which we may resort for handling the complex decision problems involving uncertainty and risk that climate change implies for forest managers. Modelling approaches that could support adaptive management strategies seem to be called for, not only as climate change denotes increased economic uncertainty but also because new and more reliable information becomes available as time passes and climate changes. 相似文献993.
Drought and frost resistance of trees: a comparison of four species at different sites and altitudes
Katline Charra-Vaskou Guillaume Charrier Rémi Wortemann Barbara Beikircher Hervé Cochard Thierry Ameglio Stefan Mayr 《Annals of Forest Science》2012,69(3):325-333
Context
Drought and frost resistances are key factors for the survival and distribution of tree species. 相似文献994.
Context
Rotation length is known to affect timber quality in many plantation species, but its effect on the properties of Sitka spruce (Picea sitchensis) structural timber has not been quantified. 相似文献995.
Barbara Fussi Joseph Bonello Eman Calleja Berthold Heinze 《European Journal of Forest Research》2012,131(2):347-354
The nativity of Populus alba in the Mediterranean has only been confirmed in the last decade, following the discovery of 8,000-year-old leaf imprints
in Southern France. Recent evidence has even emerged from molecular studies suggesting that the species is native to some
of the islands, and these populations may be relicts of a native flora that arrived there much earlier than previously thought.
In view of this, samples obtained from the Central Mediterranean archipelago of Malta and other neighbouring regions were
analysed to determine the native status of the Maltese populations and possibly trace their origins. All 38 samples were investigated
in order to assess the genetic diversity and origin of Maltese trees. Nuclear microsatellite analysis revealed that all 28
trees sampled from the two islands of Malta belonged to one clone. Chloroplast data suggested relatedness of the Maltese clone
to Italian P. alba samples. However, nuclear data suggested additional admixture through pollen from North Africa. Existing archival and palaeontological
records were also examined for any supporting evidence. On considering the latter records in combination with molecular evidence,
we arrived to the conclusion that arrival of this clone in Malta through human introduction in the sixteenth century is the
most likely explanation, since alternative scenarios like autovegetative propagation or arrival by seed seem highly unlikely. 相似文献
996.
Staffan Berg Janine Fischbach Franka Brüchert Mikael Poissonnet Stefania Pizzirani Anne Varet Udo H. Sauter 《European Journal of Forest Research》2012,131(1):81-94
The forest-based sector has been at the forefront in operationally implementing the sustainability concept, its associated
principles and indicators for sustainable forest management. Several methods have been developed to study environmental impacts
of forestry activities, but none of the existing tools address all the dimensions of sustainability along the whole forest
wood chain (FWC) in a balanced way. Consequently, the decision was made to develop a tool for sustainability impact assessment
(ToSIA), the modelling framework for sustainability impact assessment of FWCs. The objective of the EU Project Eforwood was
to develop ToSIA, a decision support tool. Within ToSIA, a FWC is modelled as a number of interconnected processes. For each
process, a range of economic, environmental and social indicators and their respective values are calculated, thus representing
the three pillars of sustainability. By this method, the multifunctionality of forests can be assessed and supply chains can
be compared with respect to sustainability. Sensitivity analysis and scenario techniques can be applied to learn about the
effect of expected changes to the structure of the chain, the material flows and the indicator values. In order to provide
the tool with information about forest and logging operations, data were collected at two fundamental levels: (1) a regional
level with case studies in Scandinavia, Iberia and Baden-Württemberg and (2) a European level with a case study that reflects
conditions in the 27 countries of the European Union. This paper describes and details the harvesting and logging processes
for the European countries. The results are displayed for each of the three regional case studies as well as aggregated to
five principal areas in Europe: Eastern, Northern, Western, Central and Southwest Europe. 相似文献
997.
Madhav Pandey Oliver Gailing Hans H. Hattemer Reiner Finkeldey 《European Journal of Forest Research》2012,131(3):739-746
Knowledge of SGS in plants is vital to understand the ecological and evolutionary dynamics of populations and to plan conservation
strategies. Some of the major factors that can affect spatial genetic structure (SGS) in plants are the level of gene flow,
spatial arrangement and life stages of individuals within populations. Applying six highly variable microsatellite markers,
we investigated the effect of these factors on spatial genetic structure selecting two natural populations of sycamore maple,
which is an insect-pollinated, autotetraploid and an indigenous hardwood species in Germany and in other central European
countries. The two study populations had different shapes (“compact” and “elongated”) and tree densities. Significant SGS
extended to ~180 m in the elongated population and to ~35 m in the compact population. Juvenile plants of the compact population
showed significant SGS up to 40 m. Estimate of Sp statistic in high-density population was almost double of that in the population
with low density. Gene dispersal distance in the low-density population was about 9 times higher than in the population with
high density. The similar level of significant SGS in both adult and juvenile plants suggested minimal or no effect of life
stages of individuals on SGS in the sycamore maple population. The data presented in this study can provide guidelines for
seed collection and to establish populations for the conservation and management of genetic resources of the species. 相似文献
998.
999.
Wibke Himmelsbach Eduardo J. Treviño-Garza Humberto González-Rodríguez Marco A. González-Tagle Marco V. Gómez Meza Oscar A. Aguirre Calderón A. Eduardo Estrada Castillón Ralph Mitlöhner 《European Journal of Forest Research》2012,131(2):355-367
Water availability and salt excess are limiting factors in Mexican mixed pine-oak forest. In order to characterise the acclimatation
of native species to these stresses, leaf water (Ψw) and osmotic potentials (Ψs) of Juniperus flaccida, Pinus pseudostrobus and Quercus canbyi were measured under natural drought and non-drought conditions under two different aspects in the Sierra Madre Oriental.
Factorial ANOVA revealed significant differences in Ψw and Ψs between two aspects, species and sampling dates. In general, all species showed high predawn and low midday values that declined
progressively with increasing drought and soil–water loss. Seasonal and diurnal fluctuation of Ψw and Ψs were higher for J. flaccida and Q. canbyi than for P. pseudostrobus. Leaf Ψw and Ψs were mainly correlated with soil water content, while Ψs of P. pseudostrobus were hardly correlated with environmental variables. Thus, species have different strategies to withstand drought.
P. pseudostrobus was identified as a species with isohydric water status regulation, while J. flaccida and Q. canbyi presented water potential patterns typical for anisohydric species. The type of water status regulation may be a critical
factor for plant survival and mortality in the context of climate change. Nevertheless, for precise conclusions about the
advantages and disadvantages of each type, further long-term investigations are required. 相似文献
1000.
Ashraful Alam Antti Kilpeläinen Seppo Kellomäki 《European Journal of Forest Research》2012,131(3):655-667
An ecosystem model (Sima) was utilised to investigate the impact of forest management (by changing both the initial stand
density and basal area thinning thresholds from current recommendations) on energy wood production (at energy wood thinning
and final felling) and management-related carbon dioxide (CO2) emissions for the energy wood production in Finnish boreal conditions (62°39′ N, 29°37′ E). The simultaneous effects of
energy wood, timber and C stocks in the forest ecosystem (live and dead biomass) were also assessed. The analyses were carried
out at stand level during a rotation period of 80 years for Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies L. Karst.) growing in different fertility sites. Generally, the results showed that decreased basal area thinning thresholds,
compared with current thinning, reduced energy wood (logging residues) and timber production, as well as carbon stocks in
the forest ecosystem. Conversely, increased thinning thresholds increased energy wood production (ca. 1–27%) at both energy
wood thinning and final felling and reduced CO2 emissions (ca. 2–6%) related to the production chain (e.g. management operations), depending on the thinning threshold levels,
initial stand density, species and site. Increased thinning thresholds also enhanced timber production and carbon stocks in
the forest ecosystem. Additionally, increased initial stand density enhanced energy wood production for energy wood thinning
for both species, but this reduced energy wood production at final felling for Scots pine and Norway spruce. This study concluded
that increases in both initial stand density and thinning thresholds, compared with the current level, could be useful in
energy wood, timber and carbon stocks enhancement, as well as reducing management-related CO2 emissions for energy wood production. Only 2.4–3.3% of input of the produced energy (energy wood) was required during the
whole production chain, depending on the management regime, species and sites. However, a comprehensive substitution analysis
of wood-based energy, in respect to environmental benefits, would also require the inclusion of CO2 emissions related to ecosystem processes (e.g. decomposition). 相似文献