By using an incomplete factorial mating design between twenty Pinus strobus L. female and seven P. wallichiana Jack. male trees, a number of 34 full-sib families were obtained. The objective of this experiment was to combine the fast growing of the former species with moderately to high resistance to blister rust (Cronartium ribicola Fich. in Rabenh.) of the latter one. The hybrid families were artificially inoculated at age two, and field planted at age four. The plantation took place within an old black current (Ribes nigrum L.) heavy infected by blister rust. In order to provoke new infections, this time naturally, the pine rows were planted in between the black currant ones. Diameters at breast height, tree height, tree growth rate volume, stem straightness and tree survivals were the traits measured at age 32 from seed. The first trial thinning was simultaneously applied with the present measurements. The average tree survival was 74.8% in hybrids, 8.3% in Pinus strobus and 27.8% in P. wallichiana. Highly significant (p < 0.01) differences were found between hybrid families for all traits except stem straightness. Genetic coefficient of variation at family level was 13.7% for tree volume growth rate and 15.9% for tree survival, but only 2.1% for tree straightness. Broad-sense family heritability estimates were 0.530 for diameter at breast height, 0.596 for stem height, and 0.564 for stem volume growth rate, 0.166 for stem straightness, and 0.539 for tree survivals. Similarly, the individual tree narrow-sense heritability estimates were 0.138 for diameter at breast height, 0.209 for stem height, 0.149 for stem volume growth rate, and 0.022 for stem straightness. If the best 5, 10 and 15 of 34 families were selected, a genetic gain of 17.7%, 13.4% and 10.2%, respectively, may be achieved in tree survival or blister rust resistance. Similarly, if the best 5%, 10% and 15% individuals within the best hybrid families were selected, a genetic gain of 4.7%, 4.0% and 3.6% in diameter at breast height and 10.7%, 9.1% and 8.1% in tree volume growth rate could be made. The estimated genetic gains indicated that a program aimed at improving growth traits and survival through interspecific hybridization could be successfully achieved.

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Several methods for the estimation of functional diversity are employed in plant communities. However, it is hard to select the most suitable measures in practice. This work presents comparisons of nine distance-based measures applied to functional diversity analysis in forest communities (36 plots) along an elevational gradient in the Pangquangou Reserve, China. The employed indices and methods were: functional attribute diversity (FAD), Raos functional diversity (Raos index), single linkage (SL), complete linkage (CL), Unweighted Pair Group Method with Arithmetic Mean (UPGMA), Unweighted Pair-Group Method using Centroids (UPGMC), Median linkage (Median), fuzzy equivalence diversity (Fuzzy index) and minimum spanning tree index (MST). The results showed that all the nine measures successfully quantified the functional diversity in plant communities and described the changes along environmental gradient. It was concluded that all the employed indices and methods were equally effective and significantly correlated. Comparatively, fuzzy index, MST, UPGMC, UPGMA and Median were more suitable and should have priority over the other four measures in functional diversity analysis. A combination of a few measures of functional diversity within the same study was recommended. Functional diversity indices were significantly decreasing with elevation and correlated with species richness in the studied forest communities. 

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The relationships among ecological conditions, morphological characteristics and total flavonoid content in Fragaria vesca L. species growing from the beech (710 m a.s.l.) to dwarf pine altitudinal zone (1550 m a.s.l.) in the western part of the Chocské vrchy Mts. (Western Carpathians) were evaluated on 10 plots. Different habitats were studied using geobiocoenological typology system in order to investigate its ecology. It has been found out that F. vesca occurs in a variety of habitats with different trophic conditions (oligo-mesotrophic, mesotrophic, mesotrophic calciphile, nitrophilous calciphile and calciphile ranges) and as a rule reached significantly higher values of measured parameters (number of leaves, length of the longest leaf, dry weight and total flavonoid content) in the mesotrophic calciphile, mesotrophic and calciphile ranges of the 5th fir-beech and 8th dwarf pine altitudinal zones. On the other hand, average values of specific energy accumulated in strawberry leaves were significantly lower in calciphile conditions of the 4th beech and 8th dwarf pine altitudinal zones. From the measured parameters, mean number of leaves in strawberry rosettes and rosette weight were as a rule increasing from lower to higher altitudinal zones. The results of regression analysis confirm moderate positive linear relationship between these parameters and an altitude (R = 0.33). The flavonoid contents were as a rule decreasing from lower to higher altitudinal zones. The correlation of the flavonoid contents and an altitude was strong (R = 0.77). In the case of dependence rosette energy and length of the leaf on an altitude there were found out the regression relationships uncorrelated. 

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China contains 119 million hectares of natural forest, much of which is secondary forest. An accurate estimation of the biomass of these forests is imperative because many studies conducted in northeast China have only used primary forest and this may have resulted in biased estimates. This study analyzed secondary forest in the area using information from a forest inventory to develop allometric models of the aboveground biomass (AGB). The parameter values of the diameter at breast height (DBH), tree height (H), and crown length (CL) were derived from a forest inventory of 2,733 trees in a 3.5 ha plot. The wood-specific gravity (WSG) was determined for 109 trees belonging to ten species. A partial sampling method was also used to determine the biomass of branches (including stem, bark and foliage) in 120 trees, which substantially easy the field works. The mean AGB was 110,729 kg ha1. We developed four allometric models from the investigation and evaluated the utility of other 19 published ones for AGB in the ten tree species. Incorporation of full range of variables with WSG-DBH-H-CL, significantly improved the precision of the models. Some of models were chosen that best fitted each tree species with high precision (R2 = 0.939, SEE 0.167). At the latitude level, the estimated AGBof secondary forest was lower than that in mature primary forests, but higher than that in primary broadleaf forest and the average level in other types of forest likewise. 

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In recent years, linear mixed models (LMM) have become more popular to deal with spatial effects in forestry and ecological data. In this study, different structure specifications of linear mixed model were applied to model tree height-diameter relationships, including LMM with random blocks only (LMM-block), LMM with spatial covariance only (LMM-covariance), and the combination of the last two (LMM-block-covariance). Further, the between-group heterogeneous variances were incorporated into LMM-covariance and LMM-block-covariance. The results indicated that, in general, LMM-covariance significantly reduced spatial autocorrelation in model residuals, while LMM-block was effective in dealing with spatial heterogeneity. LMM-block treated the blocks as random effects and avoided the estimation of parameters of the variogram model. Thus, it produced better model predictions than LMM-covariance. LMM-block-covariance took both block effects and spatial covariance into account, and significantly improve model fitting. However, it did not produce better model predictions due to the increase of model complexity and estimation of the local variogram within each block. 

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Taper functions are required in modern forest management in estimation of the end forest products, to be classified for their life time in the environment. Based on a sample of 1640 trees of 10 species measured in volume, biomass and taper project on Mexicos northern temperate, mixed, uneven-aged coniferous forests, 12 stem profile taper functions were fitted in order to select the equation that provides better diameter estimates at commercial tree height. Although several equations fitted better specific tree species, the Newnham (1990) equation consistently yielded better diameter estimates at any length of the stem for all studied species. The confidence intervals on the Newnham (1990) equation parameters showed that each species has an unique stem profile and, therefore, single parameter equations are reported. Because of lack of analytical integration, the recommended taper equation (when numerically integrated) provided compatible, unbiased total bole volume when contrasted to conventional timber volume assessments. Data for 637 circular, 1/10 ha, plots from temperate forests of Central Durango, Mexico estimated a mean of 135 m3 ha-1, of which 18, 59, 30, and 17 m3 ha-1 could be classified as poles, sawn wood, plywood and secondary forest products, respectively. This information can be used for the planning of the forest industry to optimize forest products derived from timber harvesting, as well as for estimating other environmental components. 

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A study was conducted to examine the impact of land?use on soil fertility in an Alfisol, at Dharamshala district of north western Himalayan region, India. Soil samples were collected from 0-15, 15-30, 30-45 and 45-60 cm soil depths of five land-uses viz. natural forest of Pinus roxburghii, grassland, horticulture, agriculture and wasteland. Soil was examined for pH, organic carbon (OC), electrical conductivity (EC), cation exchange capacity (CEC), available nitrogen (N), phosphorus (P), exchangeable calcium (Ca), magnesium (Mg), potassium (K), aluminium (Al), microbial biomass carbon (MBC), microbial biomass nitrogen (MBN), microbial biomass phosphorus (MBP), acid phosphatase activity (APHA) and dehydrogenase activity (DHA). Soil pH varied from 5.22 in forest and 5.72 in grassland. OC content was higher in forest (3.01%), followed by grassland (2.16%) and was least (0.36%) in deeper layers of agriculture. Highest N content was found under forest (699, 654, 623 and 597 kg/ha, at 0-15, 15-30, 30-45 and 45-60 cm depth, respectively), followed by grassland, horticulture and agriculture and least in wasteland. Exchangeable Ca and Mg were higher in grassland (0.801 c mol kg-1 and 0.402 c mol kg-1, respectively). Exchangeable K and Al were higher under forest (0.231 c mol kg-1 and 1.89 c mol kg-1, respectively) least in wasteland. Soil biological properties were highest under surface soil of forest (576 mg kg-1, 31.24 mg kg-1, 6.55 mg kg-1, 29.6 mg PNP g-1h-1 and 35.65 ľg TPF 24 h-1 g-1 dry soil, respectively for MBC, MBN, MBP, APHA and DHA) and least in 45-60 cm layer, under wasteland. The forest had a higher fertility index and soil evaluation factor followed by grassland, horticulture, agriculture as compared to wasteland. 

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Biodiversity and forest management are analyzed for a 500 ha privately owned forest within the Natura 2000 area ROSCI0122 Muntii Fagaras. Habitat types and indicator species are identified to measure environmental quality. Working towards an integrated approach to conservation, a range of options that will result in sustainable forest management are then considered. For beech forests light heterogeneity emerges as a crucial management target to ensure tree species richness and structural diversity as a basis for saving indicator species such as Morimus funereus, Cucujus cinnaberinus, Bolitophagus reticulatus and Xestobium austriacum. For spruce forests thinning over a broad range of diameters and maintenance of veteran trees would provide habitats for indicator species such asOlisthaerus substriatus. The populations of a number of bird species would be increased by strip-harvesting slopes: species such as Tetrao urogallus, Bonasia bonasia and Ficedula parva prefer forest margins. Steep slopes, and the areas around springs and watercourses, as well as rock faces, should remain unmanaged. Future management should start with a grid-based inventory to create an objective database of forest structure and life. An example is presented for high-elevation spruce forest. The inventory should quantify the variations in diameter, height and volume of trees per unit area. Such data would allow the advanced planning of forest operations. We discuss a wide range of administrative and organizational changes; changes that are needed for the sustainable forest management of the vast close-to-natural forests of the Muntii Fagaras, the maintenance of the Nardusgrasslands and the protection of wetland vegetation around springs and streams in this Natura 2000-area. 

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