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北京松山自然保护区油松种群生活史及其空间分布格局 被引量:4
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作者 牛丽丽 余新晓 +4 位作者 刘淑燕 刘彦 岳永杰 王小平 陈俊崎 《北京林业大学学报》 CAS CSCD 北大核心 2008年第S2期17-21,共5页
该文从生命表特征、年龄结构、存活曲线以及种群不同龄期个体空间分布格局4个方面,研究了松山自然保护区油松种群的生活史动态特征与空间分布规律。结果表明:①油松种群在其生长过程中,当胸径达到22.5cm左右时,由于种内不同个体间为争... 该文从生命表特征、年龄结构、存活曲线以及种群不同龄期个体空间分布格局4个方面,研究了松山自然保护区油松种群的生活史动态特征与空间分布规律。结果表明:①油松种群在其生长过程中,当胸径达到22.5cm左右时,由于种内不同个体间为争夺空间与阳光,将遭遇一次死亡高峰;随后将进入一个平稳的生长期,随着龄级的增长,死亡率逐渐升高,直至其衰老死亡。②油松种群的存活曲线基本接近DeeveyⅢ型(曲线凹型)。③油松种群不同龄期个体的分布格局、龄期间的空间关联与尺度有密切的关系,在小尺度上油松各龄期趋于聚集分布,龄期间有较强的关联性;当空间尺度大于临界值时,油松各龄期趋于随机分布,龄期间的空间关联性减弱。 展开更多
关键词 种群结构 空间分布格局 空间关联 龄期 种群动态
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Culm characteristics and volume-weight relationship of a forest bamboo(Melocanna baccifera(Roxb.) Kurz) from northeast India 被引量:2
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作者 Pator Singnar Arun Jyoti Nath Ashesh Kumar Das 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第4期841-849,共9页
Culm characteristics of Melocanna baccifera, locally 'muli', culms at five different culm ages of 11 girth classes (5-6 to 15-16 cm) were studied from Cachar Dis- trict of southern Assam, northeast India. We recor... Culm characteristics of Melocanna baccifera, locally 'muli', culms at five different culm ages of 11 girth classes (5-6 to 15-16 cm) were studied from Cachar Dis- trict of southern Assam, northeast India. We recorded internode length, internode diameter, number of internodes per culm, total culm height, total culm green weight and total culm volume of all five culm age classes. Data were gathered on 165 culms, each culm age class containing 33 culms with 3 culms per girth class. Culm height ranged from 3.2 to 15.3 m with highest mean of 9.15 m (in threeyear old culms) and maximum culm height was recorded in four-year old culms. Highest mean and maximum internode length (27.45 and 54.2 cm, respectively), internode diameter (3.12 and 4.75 cm, respectively) and total culm green weight (5.42 and 12.87 kg/culm, respectively) were recorded in three-year old culms and lowest in current-year culms. Best fitted regression models for all parameters were developed. Significant linear relationships between culm green weight and culm solid volume were documented for all five culm age classes. Their corresponding best-fit regression models were also developed. 展开更多
关键词 Regression model - Volume equation ageclass Girth class Yield determination
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