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1.

 Introduction   

The limited ability of Quercus species to regenerate naturally in Mediterranean forests has led to the development of various artificial regeneration methods; however, there is no general consensus as to what specific method is the best one for this purpose.  相似文献   

2.

• Introduction   

The recognition of endangered species takes into account geographic isolation and small size of populations, as is the case of two populations of Pinus caribaea var. hondurensis distributed in México.  相似文献   

3.

• Background   

The Holm oak (Quercus ilex ssp. ballota [Desf.] Samp.) is an evergreen tree widely distributed in the western Mediterranean Basin. Forest restoration programs using this species have enjoyed only limited success, and knowledge concerning the effect of fertilization on plant quality and post-transplantation response is sparse.  相似文献   

4.

Context  

The bark beetle, Pityogenes chalcographus, is one of the main pests in Picea abies stands, and it has also been found on other European Pinaceae species. With massive introductions of North American conifer species into European forests, this insect has extended its host range to exotic Pinaceae species.  相似文献   

5.

Introduction   

The aims of this study were to identify the climatic conditions controlling the distribution of Sasamorpha borealis and to assess the impact of climate change on the species in Japan.  相似文献   

6.

• Introduction   

As a forest species, genetic variability is high in teak (Tectona grandis) and domestication of the species is very recent. The selection effect among qualitative and quantitative traits is therefore expected to be strong. Native provenances and clonal seed orchard families were compared in this study.  相似文献   

7.

Context  

The European black poplar (Populus nigra) is considered one of the most seriously endangered indigenous tree species. However, the total area covered by monoclonal plantations of hybrid poplar is growing, because of the high profitability of these trees.  相似文献   

8.

• Introduction, Material and Methods  

The genetic structure and diversity of ten natural populations of Juniperus phoenicea L. from the western part of the species range have been studied using random amplified polymorphic DNA (RAPD) markers.  相似文献   

9.

Context  

Australian blackwood (Acacia melanoxylon), is a fast-growing, high-quality, appearance-grade timber species native to eastern Australia. Some of its key wood properties are percentage heartwood, heartwood colour, basic density, wood stiffness and green moisture content. Variation in these properties affects log value, processing and marketing.  相似文献   

10.

• Introduction  

We present a study on genetic variation in natural durability traits of young-aged Eucalyptus cladocalyx, a species adapted to temperate, low rainfall regions. Our motivation was the production of naturally durable posts for applications such as vine trellises, a sector dominated by heavy metal preservative-treated wood in some of the world’s main wine-producing countries.  相似文献   

11.

• Introduction  

The study of phenotypic and genetic differentiation between incipient species or species that have recently diverged provides insights into the evolutionary history of species complexes and may contribute to our understanding of how species will evolve in contrasting environmental conditions.  相似文献   

12.
13.
14.

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   

15.

• Introduction   

Laricio pine (Pinus nigra J.F. Arn. ssp. laricio (Poiret) Maire var Corsicana Hyl.) is a form of black pine endemic to Corsica, that may now be under threat due to current fire regimes and competition with maritime pine (Pinus pinaster Aiton).  相似文献   

16.

• Background  

Maritime pine (Pinus pinaster Ait.) is a common conifer species in Portugal that contributes significantly to the national economy. Accurate classification of forest productivity based on site index and height growth dynamics is the main basis for sustainable forest management of this species.  相似文献   

17.

•Introduction   

Silviculture systems applied in Nothofagus pumilio forests are based on opening the canopy to stimulate natural regeneration by modifying light and soil moisture. The objective is to evaluate regeneration dynamics of N. pumilio along different forest canopy and solar radiation gradients.  相似文献   

18.

• Introduction  

Stem CO2 efflux (E s) is a significant component of total ecosystem respiration, but there is only scant information on seasonal variations in E s in tropical rainforests and on the main factors explaining these variations.  相似文献   

19.

Introduction   

Roe deer (Capreolus capreolus) browsing pressure on vegetative regeneration of Turkey oak (Quercus cerris) and chestnut (Castanea sativa) and roe deer use of coppiced areas were investigated.  相似文献   

20.

• Background   

The effects of foliar nutrients and environmental variables on site productivity in Maritime pine (Pinus pinaster Ait.) stands in Asturias (NW Spain) were studied.  相似文献   

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