The Study On Growth And Physiological Characteristics Of Main Species In Picea

There are about 45 Piced Dietr plants around the world, which are widespread in the northern hemisphere, making up the main building group of the types of climax at circumpolar and low-latitude high altitude gradient and it’s very important in the terrestrial ecosystem niche. The good timber properties of spruce material, large number of unit plant, high density population, high volume in per unit area, good diameter of tree species, low operating costs and the main material of worldwide pulp and wood make it become very important in the cold and temperate coniferous timber forest in the world. There are 18 species and 7 varieties distributed in our country,mainly in the western mountainous areas and the high northern latitudes. They form a major building group of mountain areas in west China, and are an important industrial timber species and ecological tree species in these areas. From the perspective of wood security, we should strengthen the tree species(class)’s genetic improvement research and breeding. This study used the 17 spruce trees of 6- year- young forest as the object, which are in the National Germplasm Repository Germplasm Resources Preservation. The research, through studying the growth characteristics,morphological characteristics, photosynthetic physiological characteristics, water use efficiency and nutrient elements content of various tree species, is aimed at revealing the main tree species’ s growth, morphological and photosynthetic physiological characteristics as the general rule, and providing support for selecting tree species for picea asperata plantation cultivation in different ecological areas and forming a complete set of cultivation techniques. Through the research, the following conclusions were drew:1.The research on the growth characteristic of 17 species suggested that when tree height growth is used as the index, the three foreign spruce growth Picea abies, Picea pungens, Picea glauca are fast-growing tree species in the study area and the similar surrounding ecological area, and according to the investigation and observation of the early introduction of forest, they are expected to become the artificial timber forestand alternative ecological greening tree species in the future.2.In morphological study of 17 spruce trees species, it showed that there was significant difference in the main factors that affected canopy size and the level of lateral branch number and branch Angle crown chakra lateral branch length. One of the Spruce species less than 60 °for branch Angle is Picea koraiensis(55°), which had compact canopy and thick branches, and is the first tree species in the selection of trees suitable for gardening and is the densely-planted tree. One of the Spruce species between 60 °~70 ° for branch Angle is Picea mariana(61°), which has ovoid canopies and ecological traits, and can be used for ornamental purpose and timber.One of the Spruce species more than 70 °for branch Angle is Picea balfouriana(74°),and this kind of tree has a stretch canopies which take up lager space, and is the ideal of fast-growing timber forest tree species.3.Through the study on the brightness and color characteristics of picea species needles, it showed that it has great potential for choosing higher ornamental varieties in picea, especially for choosing coniferous tree species which are high bright and blue. The choice of new varieties of Picea pungens, Picea omorika and other tree species has proved this conclusion in the foreign countries.4.According to the study on 17 spruce trees in terms of their net photosynthetic rate,stomatal conductance, intercellular CO2 concentration, transpiration rate and instantaneous water use efficiency, the results showed 17 spruce trees had a very significant difference between species.Net photosynthetic rate was significantly related to the tree height, and the intercellular CO2 concentration was negatively related to the tree height significantly; stomatal conductance and transpiration rate had significantly positive correlation with the tree height. The photosynthetic physiological characteristics of picea species provides the reference for the selection and cultivation techniques for different parts of the tree.5.The acerola carbon isotope study on 17 spruce trees showed that the δ13C values of the change rate being 2.33 ‰. And the variation range was small and interspecific difference was also smaller. But in terms of the absolute value of the δ13C(δ13Cvalues of C3 plants range from-35‰ to 20‰), picea species belongs to C3 plant,which has the characteristics of C3 plant photosynthetic pathways.6.The study on N, P content and N/P of 17 spruce trees needles showed that there were significant differences between the content of N, P and N/P in different spruce tree types. The content of N, P element was negatively related to tree height growth.The results of N, P content of 17 picea species provided the basis for plantation cultivation of different species in different ecological zones, especially the confirmation of the fertilizer rate.7.Using tree height as the main index, the analysis of the correlation between new slightly, ground diameter, total crown chakra combined lateral branch length and tree height showed that there was strong correlation with tree height: the bigger value of new slightly longer, ground diameter and crown chakra combined lateral branch length was, the higher the tree height was. Then the path analysis of them showed that new slightly longer, branch angle, the number of primary lateral branch, the crown chakra combined lateral branch length and the tree height of the direct path coefficient are positive,and only the crown chakra collateral’s direct path coefficient was negative.New slightly longer through the crown chakra lateral branch length sum’s indirect path coefficient with the tree height was maximum.