Báo cáo lâm nghiệp: "Optimising the management of even-aged Pinus sylvestris L. stands in Galicia, north-western Spain" ppt

Báo cáo lâm nghiệp: "On the occurrence of web-spinning sawflies of the genus Cephalcia (Hymenoptera, Pamphiliidae) in the Czech Republic" potx

... 57–62Because of the lack of a recent survey of Cephal-cia species in the Czech Republic, the goals of this study were (i) to monitor web-spinning sawflies liv-ing on spruce in mountainous regions ... species occurrence. Canonical axes explain 65.8% of variability J. FOR. SCI., 53, 2007 (Special Issue): 57–62 59Table 1. Survey of studied web-spinning sawflies of the genus Cephalcia in the Czech ... periods of the Cephalcia species flight activities (cf. M- 1988). e flight activity started in the stud-ied localities at the end of May or at the beginning of June depending on the actual...

Báo cáo lâm nghiệp: "About the benefits of poststratification in forest inventories" potx

... (1 n/N) ì 2/n, independently of the original dis-tribution of the variable of interest. Here, although the estimate of the true mean is unbiased and the variance of the mean decreases ... samples of size 100, 32 of size 110, and 4 of size 121. In sampling a nonrectangular area, variability of the sample size will further be increased depend-ing on the irregularity of the particular ... 139JOURNAL OF FOREST SCIENCE, 53, 2007 (4): 139–148 Poststratification is well known as a means of increasing the precision of estimates in unstratiﬁed sampling by incorporating additional information...

Báo cáo lâm nghiệp: "Optimising the management of even-aged Pinus sylvestris L. stands in Galicia, north-western Spain" ppt

... thinningintensity depends on the number of the thinning, the intensityincreasing from the first thinning to the fourth. The intensity of the first thinning is around 20% of basal area, and in the ... (% of number of trees);◦ Percentage of low thinning (% of trees removed after system-atic thinning).– For the other thinnings◦ Number of years since the previous thinning;◦ Percentage of ... systematic thinning (% of number of trees);◦ Percentage of low thinning (% of trees removed after system-atic thinning).– For final felling◦ Number of years since the last thinning. The number of optimized...

Báo cáo lâm nghiệp: " Optimising the management of uneven-aged Pinus sylvestris L. and Pinus nigra Arn. mixed stands in Catalonia, north-east Spain" pps

... 747758â INRA, EDP Sciences, 2005DOI: 10.1051/forest:2004071Original article Optimising the management of uneven-aged Pinus sylvestris L. and Pinus nigra Arn. mixed stands in Catalonia, north-east ... The effect of discounting rate and length of the cutting cycleon the optimal management of mixed stands of P. sylvestris and P. nigra mixed stands was clear. With a 10-year cutting cycle the ... mixtures of Pinus sylvestris L. and Pinus nigra Arn. in Catalonia, north-east Spain, Ann. For. Sci. 61 (2004) 9–24.[38] Valsta L., A comparison of numerical methods for optimising even-aged stand management, ...

Báo cáo lâm nghiệp: " Site quality equations for Pinus sylvestris L. plantations in Galicia (northwestern Spain)" ppt

... alterna-tives for Scots pine stands in northern Spain, Ann. For. Sci. 61(2004) 163–169.[7] Bravo F., Montero G., Site index estimation in Scots pine (Pinus sylvestris L.) stands in the High Ebro Basin ... INRA, EDP Sciences, 2005DOI: 10.1051/forest:2005006Original article Site quality equations for Pinus sylvestris L. plantations in Galicia (northwestern Spain)Ulises DIÉGUEZ-ARANDA*, Juan Gabriel ... models for Scots pine (Pinus sylvestris L.) in north-east Spain, Ann. For. Sci. 60 (2003) 1–10.[44] Palahí M., Tomé M., Pukkala T., Trasobares A., Montero G., Site index model for Pinus sylvestris...

Báo cáo lâm nghiệp: "A stochastic height-diameter model for maritime pine ecoregions in Galicia (northwestern Spain)" doc

... 455Ann. For. Sci. 62 (2005) 455465â INRA, EDP Sciences, 2005DOI: 10.1051/forest:2005042Original articleA stochastic height-diameter model for maritime pine ecoregions in Galicia (northwestern ... stochastic height-diameter model was developed for maritime pine (Pinus pinaster Ait.) in Galicia (northwestern Spain). Fourwell-known growth functions were initially considered in this work, however, ... to model the response due to thinning. It is assumed that anyformulation to take into account the effect of thinning must includethe thinning intensity, the stand age at the time of thinning...

Báo cáo lâm nghiệp: "Optimising the management of Pinus sylvestris L. stand under risk of fire in Catalonia (north-east of Spain)" ppsx

... stand age when the first thinning occurs; years sinceprevious thinning for the other thinnings; remaining basal area.For the final cutting: years since the last thinning to the first regen-erative ... 493501â INRA, EDP Sciences, 2005DOI: 10.1051/forest:2005054Original articleOptimising the management of Pinus sylvestris L. stand under risk of fire in Catalonia (north-east of Spain)José ... [18]. In this study we use a simulation-optimisation system,SPINE [19], to examine the effect of risk of fire on the optimaleven-aged management of Scots pine (Pinus sylvestris L.) stands in Catalonia...

Báo cáo lâm nghiệp: "Modeling the impact of thinning on height development of dominant and codominant loblolly pine trees" pot

... growth of dominant and codominant loblolly pine trees, the mean value of total height of dominant and codominant trees was calculated for each unthinned and once thinned stand at each location (site) ... right hand side of Equation (8) for agiven set of variables. The integral of Equation (8) can also becomputed online [16].4. CONCLUSIONSThis study shows that height growth of dominant and codominant ... is the stand age, Atis the stand age at the time of thinning (A > At), and r is the rate parameter corresponding to thinning response. In orderto account for the thinning response in the...

Báo cáo lâm nghiệp: " Ranking the importance of quality variables for the price of high quality beech timber (Fagus sylvatica L.) ppt

... with the models rather than artefacts. A ranking of the importance of the timber quality variables on the basis of both models there-fore seemed acceptable.Among the quality variables the red ... explain timber prices achieved for high quality beech timber (Fagus sylvatica L.). The modelling starts with the assumption that among other variables, the buyers’ preference determines the level of ... context the paper presents such price models for high quality beech timber. A new modelling approach was used for ranking the importance of timber quality variables. 2. THEORETICAL APPROACH, HYPOTHESESAND...

Báo cáo lâm nghiệp:"Predicting the probability of seed germination in Pinus sylvestris L. and four competitor shrub species after fire" doc

... hightemperatures favoured the germination of Genista florida.Therefore, a balance between the elimination of competitor shrub species and the stimulation of the germination of Pinus sylvestris seeds must be ... 2002076Original articlePredicting the probability of seed germination in Pinus sylvestris L. and four competitor shrub species after fireMê Rosario Nuñeza, Felipe Bravoa and Leonor Calvob*a ... probability of germination was studied in the laboratory for Scots pine (Pinus sylvestris) and four shrub species characteristic of the understory in Scots pine stands in northern Spain (Cistus laurifolius,...

Báo cáo lâm nghiệp:"Optimising the management of Scots pine (Pinus sylvestris L.) stands in Spain based on individual-tree models" potx

... 10.1051/forest:2003002Original articleOptimising the management of Scots pine (Pinus sylvestris L.) stands in Spain based on individual-tree modelsMarc Palahía* and Timo Pukkalab a European Forest Institute, ... simulation-optimisation system, SPINE, for the management of Pinus sylvestris L. stands in Spain. The simulation sub-system is based on an individual-tree diameter growth model, a static individual-tree ... expectation value with 1, 2 and 3 percentdiscounting rate. Optimising the management of Scots pine stands in Spain 1072.1.3. Simulation of thinnings and regenerative cuttings The simulation sub-system...

Báo cáo lâm nghiệp:"A height-diameter model for Pinus radiata D. Don in Galicia (Northwest Spain)" docx

... 237Ann. For. Sci. 60 (2003) 237245â INRA, EDP Sciences, 2003DOI: 10.1051/forest:2003015Original articleA height-diameter model for Pinus radiata D. Don in Galicia (Northwest Spain)Carlos ... The model of Tomé gave the best height estimates. Pinus radiata D. Don / forest modelling / Galicia / height-diameter relationshipRésumé – Un modèle hauteur-diamètre pour Pinus radiata D. Don ... obtained for diameter classes in the fitting phase of the two best models (Tomé [40] andCox II [11] Mod. 2).(a)(b) A height-diameter model for Pinus radiata 241The six models classified in...

Báo cáo lâm nghiệp: "Assessing the potential of natural woody species regeneration for the conversion of Norway spruce plantations on alluvial soils" doc

... In the perspective of the conversion of Norway spruce plantations, there is a need for foresters to assess the potential of the natural woody species regeneration. We studied 50 Norway spruce plantations ... natural woody species regeneration for the conversion of Norway spruce plantations on alluvial soilsBruno HÉRAULTa*, Daniel THOENa, Olivier HONNAYba Department of Environmental Sciences ... competi-tion on the growth of seedling of four tree species on a range of soil,Q. J. For. 73 (1979) 160–171.[28] Hérault B., Bouxin G., Thoen D., Comparison of the regeneration patterns of woody species...

Báo cáo lâm nghiệp: "On the durability of Burkea africana heartwood: evidence of biocidal and hydrophobic properties responsible for durability" ppt

... by measuring the diameter of the colony estimated from the mean of two perpendic-ular diameters and expressed as a percentage of the room available for growth, i.e. the diameter of the dish. Growth ... Independently of the nature of the extraction, weight losses observed on Burkea africana blocks are weak, while beech blocks arestrongly degraded. These results suggest that the durability of Burkea africana ... effects of the different extractson the growth of brown rot and white rot fungi. In all cases, asignificant effect was observed on the growth of the myceliumat 100 and 1000 ppm of the different...

Báo cáo lâm nghiệp: " Modelling the influence of winter frosts the development of the stem canker of red oak, caused by Phytophthora cinnamomi" doc

... furthersupport to the hypothesis that winter frostis the meteorological variable limiting the distribution of the disease. The most ...

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