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作 者:杨子清[1,2] 陈平留[2] 刘健[1,2,3] 余坤勇[1,2] 廖晓丽[1] 游浩辰[1] 龚从宏[1]
机构地区:[1]福建农林大学3S技术应用研究所,福建福州350002 [2]福建农林大学林学院,福建福州350002 [3]三明学院化学与生物工程系,福建三明365004
出 处:《浙江农林大学学报》2012年第3期374-382,共9页Journal of Zhejiang A&F University
基 金:国家自然科学基金资助项目(40971043)
摘 要:杉木Cunninghamia lanceolata是中国南方主要用材树种,研究其空间分布变化规律对杉木生产经营具有重要意义。在福建顺昌县选择3块立地条件基本一致的杉木人工纯林的(国家森林资源连续清查)固定样地(分别位于低、中、高海拔),将杉木生长分为2个阶段:幼树(5 cm≤胸径〈10 cm)和成年树(胸径≥10 cm),于2003年和2008年调查了样地内杉木(胸径≥5 cm)的胸径并记录其坐标。采用Ripley’s K(r)函数改进的L(r)函数,双相关函数g(r)和角尺度Wi分析杉木空间分布格局的时空变化。3块样地角尺度分析W軘分别为0.494~0.578,0.465~0.477,0.426~0.601。研究表明:海拔对杉木林的空间分布格局无影响。从L(r)和g(r)函数曲线可看出,成年树普遍低于幼树,也即更趋于随机或均匀分布,因此,不论初始分布如何,随着时间的推移都有聚集分布向随机分布转变、随机分布向均匀分布转变的趋势。To aid in management of Cunninghamia lanceolata,the main timber species in southern China,its variation of spatial distribution pattern was analyzed.Three permanent plots of C.lanceolata plantations with approximately the same site conditions,set by China continuous forest inventory in Shunchang,Fujian,were selected.C.lanceolata growth was divided into two stages: young trees(5 cm ≤ diameter at breast height(DBH) 10 cm) and mature trees(DBH ≥ 10 cm).The DBH and coordinates of every tree(DBH ≥ 5 cm) in the permanent plots were recorded in 2003 and 2008.The function L(r),improvement of Ripley’s K(r),the paircorrelation function g(r),and the uniform angle index(Wi) were used to analyze the spatio-temporal variation of spatial distribution patterns.The three permanent plots had mean uniform angle index(W) between 0.494-0.578 in low altitudes,0.465-0.477 in medium altitudes,and 0.426-0.601 in high altitudes.Results showed that altitude did not affect the spatial distribution pattern.The L(r) and g(r) function curves of mature trees were generally lower than young trees’,i.e.tend to be more random or uniform distribution.So regardless of the initial distribution of young or mature trees,with the passage of time,there was a tendency for the aggregated distribution to change to a random distribution,and a random distribution to change to a uniform distribution.
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