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Studies On The Industrial Plantation Technology Of Silviculture And Management Of Pinus Elliottii

Posted on:2005-11-09Degree:DoctorType:Dissertation
Country:ChinaCandidate:H QiuFull Text:PDF
GTID:1103360122496177Subject:Forest cultivation
Abstract/Summary:PDF Full Text Request
Some key oriented silviculture techniques for the industrial plantation of the Pinus elliottii in the south part of Anhui Province from the aspects of elite breeding and cultivating, nursery-stock growing, site preparation effects, planting density, tending and thinning etc. were studied in this study. An oriented silviculture practice model for the industrial plantation of the Pinus elliottii was developed. The main results are as follow:1. The study on the growth and the timber characters of the Pinus elliottii provenances(1) There was significant difference in the timber air-drying density, bending strength, the modulus of elasticity of bending strength and compressive strength along grains among 19 provenances. However, there was no significant difference in the tracheid wall thickness and the tracheid wall ratio among 19 provenances. Among the seed sources the timber air-drying density, mechanics intensity and the tracheid wall ratio were not significant different. The difference in the tracheid length and width, and the tracheid wall thickness was obviously higher than the one among the seed provenances.Based on growth and timber characters, 19 provenances were divided in two types: (a) s4, sl5, sl6, s5 s6 could be used as construction timber; and (b) sl3, sl2, s3 and sl6 could be used as papermaking material.(2) The broad hereditary power of the tracheid length and width, the tracheid wall thickness and wall ratio of the timber from the Pinus elliottii seed source is 0.3707, 0.6005, 0.7182, and 0.1636 respectively. The broad hereditary power of the timber air-drying density, bending strength, the modulus of elasticity of bending strength, the compressive strength along grains and the blasting tenacity is 0.3927, 0.2589, 0.1101, 0.2896, and 0.1311 respectively. And the broad hereditary power of the height and DBH of the tree of the seed source is 0.4103 and 0.4759 respectively. Tracheid properties, timber density and the growing properties of trees of the timer of the Pinus elliottii seed source were controlled by the medium or upper-medium heredity. A high genetic gain could be made through the selection.(3) There was close relationship between timber air-drying density and its mechanics intensity. The timber tracheid parameters such as air-drying density and mechanics intensity were not related to the growing speed of the trees.2 The nursery technology of breeding the Pinus elliottii seedling(1) The seed shape had a remarkable impact on the seed properties. The middle-size seeds took up 74.8%of the total granular weight or amount. The plump sizing of the seeds has nothing to do with the size of theseeds among which the seeds in middle-size is plumpest. The per 1000-seed-weight for large andmiddle-size seeds were 75.4% and 35.7% higher than that for small size seeds.Seed-grading had no significant influent in seeds' germinating rate. The grading made the difference of thegerminating speed and the seedling height after one month of the seeds in different sizes become obvious.The growing process of the seedling height of the seeds in different sizes and the root collar diameter wasconsistent with the highest growth capacity of the seed in big size after one year. But the seedlings grownfrom the different sizes were not significant.(2) For the indexes of the seedling height variation coefficient, the percentage of I grade seedling and the biomass of a seedling, etc. of the seedlings cultivated from different sizes, the seedlings grown from large size seeds had the highest values, while the seedlings cultivated from in small-size seeds had the lowest ones. For root/stem ratio, the seedlings grown from the smaller seeds was the higher than large seeds. The order arranged according to the seedling quality indexes was as follows: large seeds > middle-size seeds > control seeds> small size seeds.(3) The root-pruning had negative influence in seedling height and the root collar diameter growth. The root-pruning damaged the root system and therefore had effect on the absorption of the water and effective fertilizers,...
Keywords/Search Tags:Pinus elliottii, Seed provenance, Plantation for industrial utilization, Silvicultural practices
PDF Full Text Request
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