The spatial distribution of standing fine roots in tree rows of different species in a 12-year-old mixed stand of ash (Fraxinus mandshurica Rupr.) and larch (Larix olgensis Henry) was studied by soil core sampling in ...The spatial distribution of standing fine roots in tree rows of different species in a 12-year-old mixed stand of ash (Fraxinus mandshurica Rupr.) and larch (Larix olgensis Henry) was studied by soil core sampling in early spring, 2001. It is found that ash and larch differ greatly in their belowground biomass distribution. Ash has much higher fine root biomass density in the soil than larch at stand level (with the max value of 4442.3 vs. 2234.9 gm-3). Both tree species deployed more fine roots in their neighboring zone, suggesting a less intensive competition between roots of the two species. Both fine root biomass density and root length density of ash in the zone between larch tree rows are greater than that of larch in zone between ash tree rows, indicating that ash is more powerful than larch in belowground competition. The spatial distribution feature of roots favors the growth of ash in the mixed stand.展开更多
为了更好地保护和利用国家珍稀濒危植物—对节白蜡(Fraxinus hupehensis Chu,Shang et Su),采用常规群落调查方法在其分布区的典型区域设置了15个样方进行群落学调查,统计分析了对节白蜡群落的物种组成、重要值、物种多样性指数等特征...为了更好地保护和利用国家珍稀濒危植物—对节白蜡(Fraxinus hupehensis Chu,Shang et Su),采用常规群落调查方法在其分布区的典型区域设置了15个样方进行群落学调查,统计分析了对节白蜡群落的物种组成、重要值、物种多样性指数等特征以及对节白蜡自然更新情况。群落物种组成分析表明,在被调查的15个样方中,共有乔木36种,灌木111种,草本60种。群落各层次物种重要值分析表明,对节白蜡在群落乔木层中占据绝对优势(45.62%);灌木层中对节白蜡的重要值最大(8.34%),但伴生的水蜡、棕榈和菱叶海桐等数量较多;草本层中薹草具有绝对优势(18.99%)。通过分析群落各层次物种的3种多样性指数(丰富度指数、多样性指数和Pielous均匀度指数)表明,对节白蜡各层次物种多样性关系为:灌木层>草本层>乔木层,反映出对节白蜡在乔木层和灌木层的存在对维持灌木物种多样性具有重要作用。通过以上分析可知,对对节白蜡的保护中应注意保护其伴生种,例如黄连木和三角枫等;对节白蜡的天然更新受人为干扰的影响较大,而对光照条件的改变是主要因素。研究认为,对节白蜡群落的可持续发展需要适当的人为干扰。展开更多
基金This study was supported by National Natural Science Foundation of China (Grant No. 30130160) and the Quick Response of Basic Research Supporting Program (Grant No.2102)
文摘The spatial distribution of standing fine roots in tree rows of different species in a 12-year-old mixed stand of ash (Fraxinus mandshurica Rupr.) and larch (Larix olgensis Henry) was studied by soil core sampling in early spring, 2001. It is found that ash and larch differ greatly in their belowground biomass distribution. Ash has much higher fine root biomass density in the soil than larch at stand level (with the max value of 4442.3 vs. 2234.9 gm-3). Both tree species deployed more fine roots in their neighboring zone, suggesting a less intensive competition between roots of the two species. Both fine root biomass density and root length density of ash in the zone between larch tree rows are greater than that of larch in zone between ash tree rows, indicating that ash is more powerful than larch in belowground competition. The spatial distribution feature of roots favors the growth of ash in the mixed stand.
文摘为了更好地保护和利用国家珍稀濒危植物—对节白蜡(Fraxinus hupehensis Chu,Shang et Su),采用常规群落调查方法在其分布区的典型区域设置了15个样方进行群落学调查,统计分析了对节白蜡群落的物种组成、重要值、物种多样性指数等特征以及对节白蜡自然更新情况。群落物种组成分析表明,在被调查的15个样方中,共有乔木36种,灌木111种,草本60种。群落各层次物种重要值分析表明,对节白蜡在群落乔木层中占据绝对优势(45.62%);灌木层中对节白蜡的重要值最大(8.34%),但伴生的水蜡、棕榈和菱叶海桐等数量较多;草本层中薹草具有绝对优势(18.99%)。通过分析群落各层次物种的3种多样性指数(丰富度指数、多样性指数和Pielous均匀度指数)表明,对节白蜡各层次物种多样性关系为:灌木层>草本层>乔木层,反映出对节白蜡在乔木层和灌木层的存在对维持灌木物种多样性具有重要作用。通过以上分析可知,对对节白蜡的保护中应注意保护其伴生种,例如黄连木和三角枫等;对节白蜡的天然更新受人为干扰的影响较大,而对光照条件的改变是主要因素。研究认为,对节白蜡群落的可持续发展需要适当的人为干扰。