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391.
Michael Heym Ricardo Ruíz-Peinado Miren Del Río Kamil Bielak David I. Forrester Gerald Dirnberger Ignacio Barbeito Gediminas Brazaitis Indrė Ruškytkė Lluís Coll Marek Fabrika Lars Drössler Magnus Löf Hubert Sterba Václav Hurt Viktor Kurylyak Fabio Lombardi Dejan Stojanović Jan Den Ouden Renzo Motta Maciej Pach Jerzy Skrzyszewski Quentin Ponette Géraud De Streel Vit Sramek Tomáš Čihák Tzvetan M. Zlatanov Admir Avdagic Christian Ammer Kris Verheyen Buraczyk Włodzimierz Andrés Bravo-Oviedo Hans Pretzsch 《Annals of Forest Science》2017,74(3):63
Key message
This data set provides unique empirical data from triplets of Scots pine ( Pinus sylvestris L.) and European beech ( Fagus sylvatica L.) across Europe. Dendrometric variables are provided for 32 triplets, 96 plots, 7555 trees and 4695 core samples. These data contribute to our understanding of mixed stand dynamics. Dataset access at http://dx.doi.org/10.5061/dryad.8v04m . Associated metadata available at https://metadata-afs.nancy.inra.fr/geonetwork/apps/georchestra/?uuid=b3e098ca-e681-4910-9099-0e25d3b4cd52&hl=eng .392.
Marcus Vinicius Vieira Borges Janielle de Oliveira Garcia Tays Silva Batista Alexsandra Nogueira Martins Silva Fabio Henrique Rojo Baio Carlos Ant?nio da Silva Junior Gileno Brito de Azevedo Glauce Taís de Oliveira Sousa Azevedo Larissa Pereira Ribeiro Teodoro Paulo Eduardo Teodoro 《林业研究》2022,33(2):591-599
In forest modeling to estimate the volume of wood, artificial intelligence has been shown to be quite effi-cient, especially using artificial neural networks (A... 相似文献
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394.
Martin K. Obrist Emilie Rathey Fabio Bontadina Marco Moretti 《Forest Ecology and Management》2011,261(3):789-798
We assessed the effect of abandonment of sylvo-pastoral practices in chestnut orchards (Castanea sativa) on bats in southern Switzerland to determine practical recommendations for bat conservation. We compared bat species richness and foraging activities between traditionally managed and unmanaged chestnut orchards, testing the hypothesis that managed orchards provide better foraging opportunities and harbour more bat species. Echolocation calls of foraging bats were sampled simultaneously at paired sites of managed and unmanaged orchards using custom made recorders. Vegetation structure and aerial insect availability were sampled at the recording sites and used as explanatory variables in the model. In a paired sampling design, we found twice the number of bat species (12) and five times higher total foraging activity in the managed chestnut orchards compared to the unmanaged ones. Bat species with low flight manoeuvrability were 14 times more common in managed orchards, whereas bats with medium to high manoeuvrability were only 5 times more common than in abandoned orchards. The vegetation structure was less dense in managed orchards. However, management did not affect relative insect abundance. Bats primarily visited the most open orchards, free of undergrowth. As a result of restricted access into the overgrown forests, the abandonment of chestnut orchards leads to a decline in bat species richness and foraging activities. Continued management of chestnut orchards to maintain an open structure is important for the conservation of endangered bat species in the southern Swiss Alps. 相似文献
395.
Paulo Henrique Muller da Silva Fabio PoggianiEdson Seizo Mori 《Forest Ecology and Management》2011,261(11):2075-2080
Some Eucalyptus species are widely used as a plantation crop in tropical and subtropical regions. One reason for this is the diversity of end uses, but the main reason is the high level of wood production obtained from commercial plantings. With the advancement of biotechnology it will be possible to expand the geographical area in which eucalypts can be used as commercial plantation crops, especially in regions with current climatic restrictions. Despite the popularity of eucalypts and their increasing range, questions still exist, in both traditional planting areas and in the new regions: Can eucalypts invade areas of native vegetation, causing damage to natural ecosystems biodiversity?The objective of this study it was to assess whether eucalypts can invade native vegetation fragments in proximity to commercial stands, and what factors promote this invasive growth. Thus, three experiments were established in forest fragments located in three different regions of Brazil. Each experiment was composed of 40 plots (1 m2 each one), 20 plots located at the border between the forest fragment and eucalypts plantation, and 20 plots in the interior of the forest fragments. In each experimental site, the plots were paired by two soil exposure conditions, 10 plots in natural conditions and 10 plots with soil exposure (no plant and no litter). During the rainy season, 2 g of eucalypts seeds were sown in each plot, including Eucalyptus grandis or a hybrid of E. urophylla × E. grandis, the most common commercial eucalypt species planted in the three region. At 15, 30, 45, 90, 180, 270 and 360 days after sowing, we assessed the number of seedlings of eucalypts and the number of seedlings of native species resulting from natural regeneration. Fifteen days after sowing, the greatest number of eucalypts seedlings (37 m−2) was observed in the plots with lower luminosity and exposed soil. Also, for native species, it was observed that exposed soil improved natural germination reaching the highest number of 163 seedlings per square meter. Site and soil exposure were the factors that have the greatest influence on seed germination of both eucalypt and native species. However, 270 days after sowing, eucalypt seedlings were not observed at any of the three experimental sites. The result shows the inability of eucalypts to adapt to condition outside of their natural range. However, native species demonstrated their strong capacity for natural regeneration in forest fragments under the same conditions where eucalypts were seeded. 相似文献