丝栗栲林生长与生产力的研究

在福建省邵武市洪墩采育场，调查丝栗栲林标地１０块，做平均木、树干解析木９株，杉木人工林标地２块，研究丝栗栲的生长与生产力，结果表明：丝栗栲林的胸径、树高及单株材积总生长量，均随年龄的增加而增加；胸径２０ａ前生长最快；树高１６ａ前生长最快；材积３６ａ时尚未有下降的趋势。胸径、树高平均生长量，随年龄增加而增加，当生长量达高峰后，则随年龄的增加而下降；胸径生长高峰，好立地１２ａ，中、劣立地１５ａ；树高生长高峰，好立地１０ａ，中立地８ａ，劣立地１２ａ；材积平均生长量，随年龄增加而增加，好、劣立地３６ａ时仍未下降，中立地３４ａ时生长量最大。胸径、树高连年生长量随年龄增加而下降；材积连年生长量，随年龄增加而增加，当生长量达高峰后，则随年龄增加而下降，生长高峰出现的年龄，好立地２８ａ，中立地２２ａ，劣立地２６ａ。在相似的立地条件下，丝栗栲林的蓄积量比杉木人工林低，但乔木层总生物量比杉木林高。

Growth and Productivity of Castanopsis fargesii Stands

To determine the growth process and productivity of Castanopsis fargesii Franch stands,9 average trees were sampled and analyses of tree growth process were done based on a stand investigation in 10 sample plots in C. fargesii stands and 2 sample plots in Chinese fir stand,in Hongdeng Forest Farm of Shaowu,Fujian Province.The results showed that:the total increments of DBH,tree height and individual volume of trees increased as age of trees went up; DBH increased fast before 20 years old;the growth of tree height were fast before 16 years old;and no decline evidence of timber increment occurred until age of 36 in the stand.Before the climax of DBH increment and of mean increment of height occurred,their increment went up as age of trees increased;but declined after the climax.The increment climax of DBH occurred at age of 12 and 15 in high quality site and low middle quality site respectively;the increment climax of height occurred at age of 10,8 and 12 in high,middle and low quality site,respectively.The average increment of timber volume went up as tree age rose until the age of 36 in high and low quality site;moreover,its climax emerged at the age of 34 in a middle quality site.The yearly increment of DBH and height fell down as the age went up.Yearly volume of timber increased as the age went up before the increment climax emerged;but declined after the climax,in which its increment climax of timber volume occurred at age of 28,22 and 26 respectively.Besides,the total timber volume of C. fargesii stands was lower than that in Chinese fir stands in similar site,but the biomass of tree layer was higher than that in Chinese fir stands.