于洞庭湖区的岳阳市君山区、沅江市、临澧县、常德市鼎城区，选择2008年春造林的杨树人工林，按平原、滩地、丘陵平地与丘陵坡地4种立地类型设立标准样地，对洞庭湖区不同立地杨树的生长规律进行研究。结果表明：在平原、滩地、丘陵平地、丘陵坡地等4种立地，6年生杨树林的年均树高生长量分别为2.8 m、2.3 m、2.6 m、1.5 m，年均胸径生长量分别为2.6 cm、2.6 cm、2.3 cm、1.9 cm，年均单株材积生长量分别为0.0240 m3、0.0180 m3、0.0180 m3、0.0063 m3，年均单位面积蓄积生长量分别为20.0 m3/hm2、15.5 m3/hm2、15.5 m3/hm2、7.8 m3/hm2；4种立地以平原地的杨树生长最好，并且立地条件越好，杨树进入快速生长期也越早；在平原，6年生杨树的胸径生长已经因林分过密而放缓，但树高、单株材积、单位面积蓄积生长量都还处于快速生长期。%Setting up the sample plots according to the four site types of plain,beach,hilly-flatland and slope land,the growth regularity of poplar in different sites of Dongting Lake areas is researched.The results show that,the annual aver-age height growth of the 6-year-old poplar growing in the plains,beaches,hilly-flatland and slope land are 2.8 m,2.3 m,2.6 m and 1.5 m respectively,the annual average DBH growth are 2.6 cm,2.6 cm,2.3 cm and 1.9 cm respective-ly,the annual average individual volume growth are 0.024 0 m3 ,0.018 0 m3 ,0.018 0 m3 and 0.006 3 m3 respectively, and the annual average volume growth per unit area are 20.0 m3/hm2 ,15.5 m3/hm2 ,15.5 m3/hm2 and 7.8 m3/hm2 respectively.The poplar grow best in the plains of the four kinds of site conditions,and it is the earlier with the better site conditions that poplar enter into a fast-growing period,the DBH growth of the 6-year-old poplar growing in the plains has been slowed by high density,but the growth of tree height,individual volume and volume per unit area are in rapid growth period.
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