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对江西大岗山１７年生杉木人工林树冠内不同年龄针叶面积（ＮＡ）、叶面积密度（ＮＡＤ）的垂直、水平和二维空间分布以及当年生针叶面积及其密度分布的季节动态进行了测定和模拟。结果表明，生长盛期杉木单个树冠平均ＮＡ 为２５．４２ ｍ ２，平均ＮＡＤ为２．２７２ ７ ｍ ２·ｍ － ３，其中２年生及其以上老叶（简称２年生）大于１年生，１年生大于当年生。ＮＡＤ 的水平和垂直分布均可用β分布函数表达，而相对冠高和冠径的二次趋势面表达式可很好地描述ＮＡＤ二维空间分布。树冠内ＮＡＤ在冠中上部枝的中前部最大，但不同年龄ＮＡＤ的分布不同，当年生针叶更接近于树冠顶部和最外层，１年生针叶最大ＮＡＤ位于树冠中部枝的中前部，２年生针叶最大ＮＡＤ出现于树冠中下部枝的中部。随着林龄的增加，累积叶面积指数降低，ＮＡ在树冠中的垂直分布重心向上移动。当年生针叶干质量和ＮＡ 的季节生长进程适合Ｌｏｇｉｓｔｉｃ方程。生长末期树冠内平均ＮＡ 和ＮＡＤ可达２９．４２４ ３ ｍ ２和２．６３０ ７ ｍ ２·ｍ － ３。
The vertical, horizontal and two-dimensional spatial distribution of needle leaf area (NA) and leaf area density (NAD) and the seasonal dynamics of annual coniferous area and its density distribution in canopy of 17-year-old Chinese fir plantations in Dagangshan of Jiangxi Province Measured and simulated. The results showed that the average NA was 25.42 m 2 and the average NAD was 2.272 7 m 2 · m - 3 in the single canopy of Chinese fir during the growth period. The average annual NAD was 2.272 7 m 2 · m -3, Aged greater than the current students. The horizontal and vertical distributions of NAD can be expressed by β distribution function, while the quadratic trend surface expression relative crown height and crown diameter can well describe the two-dimensional spatial distribution of NAD. The NAD in the crown was the largest in the middle anterior branch of the crown, but the distribution of NAD was different at different ages. The annual needle was closer to the top and the outermost of the canopy. The largest NAD of 1 year old needle was located in the anterior part of the middle branch The maximum NAD of 2-year-old needles appeared in the middle of the middle and lower branches of the crown. With the increase of age, the cumulative leaf area index decreased and the vertical center of gravity of NA in the canopy moved upward. The annual growth of coniferous stems and NA is suitable for Logistic equation. The average NA and NAD in the canopy at the end of growing period reached 29.424 3 m 2 and 2.630 7 m 2 · m - 3.