Study On The Growth And Site Classification Of Teak(Tectona Grandis L.f.) Plantation

Teak?Tectona Grandis L.f.?is semi-deciduous or deciduous tall tree of Verbenaceae Tectona Linn..Fast growth and excellent quality of Teak make it playing an important role in the world precious timber market.With decreasing supply of the country of origin and increasing demand of the domestic market,development of domestic teak plantation in recent years has become an investment hot spot in southern China.122 sample plots in size of 20 m × 20 m were set in Xishuangbanna Dai Autonomous Prefecture,Jieyang City,and Hainan Province teak plantations for surveying the growth of teak and recording the site topography factors such as slope,slope position,aspect,elevation and so on in each sample plot.Soil samples were also collected for analyzing soil chemical and physical properties.Classifying site productivity and site types for teak plantations resulted from studying the relationship between site factors and the growth of teak plantations,and finding the dominant factors which affected the growth of teak,will provide a scientific basis for site selection of teak plantation development in China.Specific results are as follows:?1?There were differences among growth of teak plantationin three areas which have different climate and site conditions.The multiple comparisons of 13-year-old teak plantation showed the growth of Banna were significantly better than Jieyang and Hainan.The growth of different sites in same region had differences since different topography and soil.Annual average growth in height and diameter at breast height?DBH?of teak in Balianrong were better than other sites in Banna,Yunnan.The growth of height and diameter at breast height in Dongculiao,Guangdong province were btter than Gaoming moutain and Behind Company,Guangdong province.The growth of height and diameter at breast height in Jianfeng,Hainan province worse than other three sites.?2?The Weibull distribution model were used to fit teak plantation diameter distribution with good result.The Weibull diameter distribution parameters prediction model of teak plantation were fitted and the rate of sample passing K-S test were 100%,showed the parameter prediction model suit the diameter distribution of teak plantation.?3?Fitting teak plantation height-diameter growth curve model to study the rule of height with the change of DBH,the model suits Xishuangbanna,Jieyang,Hainan teak plantations were fitted.The result showed that all fitting models reached very significant level,the best model for comprehensive and Banna,Jieyang were exponentiation model,and the best model for Hainan was polynomial model.?4?Teak grew better in silty loam with good drainage system than in sandy loam or heavy loam.Teak liked to grow in 1.0¹.3 g·cm-3 bulk density soil.Soil acidity had significant influence on the growth of teak.In strong acid soil with high concentration of soil exchangeable aluminum and available iron,teak grew extremely poor.In the site with high levels of total N,total K,available Zn²⁺,exchangeable Ca²⁺,exchangeable Mg²⁺,and base saturation,teak grow best.?5?Soil nutrient grades were divided by stepwise regression method principal component analysis and were used with the suitable site factors to fit the site quality evaluation model in Xishuangbanna,Jieyang,Hainan teak plantation by quantity theory I.The R-squared of fitting model are high and the model all reached extremely significant.The productivity group?High productivity group,Middle productivity group,Low productivity group,Poor productivity group,?were divided according to the quantity regression results,and site type were classified by suitable site factors,The growth of teak and site characteristics of each productivity group were evaluated.