...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>New Forests >Growth Characteristics of Introduced Green Ash (Fraxinus pennsylvanica Marshall) and Narrow-leaved Ash (F. angustifolia L.) in Lowland Forest Region in Croatia
【24h】

Growth Characteristics of Introduced Green Ash (Fraxinus pennsylvanica Marshall) and Narrow-leaved Ash (F. angustifolia L.) in Lowland Forest Region in Croatia

机译：克罗地亚低地森林地区引进的绿灰（Fraxinus pennsylvanica Marshall）和窄叶灰（F. angustifolia L.）的生长特性

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

American ash and green ash were used about 100 years ago in the lowland regions of Croatia to afforest and fill the depressions where narrow-leaved ash (Fraxinus angustifolia Vahl) could not survive. The growth of mean stand trees of green ash and narrow-leaved ash were studied in 14 sites (a systematic sample of 0.03 ha circular plots). A total of 212 trees were cored and 11 cross-section samples were taken for stem analysis. The Mann-Whitney U-test showed statistically significant differences in radial growth between narrow-leaved and green ash at all sites. In green ash, the test revealed a statistically significant difference in the radial growth between the last 20-year-period and the preceding 20-year-period. Green ash are characterised by the fact that annual radial growth in the first 20–30 years is very high (above average), while after that it is consistently suppressed below average growth and amounts to only about 1.5 mm. The obtained results of faster growth and a low final growth value suggest that green ash should be managed with short rotations, since this important pioneer species is intended to improve the conditions in those sites where forest vegetation has regressed.
机译：大约100年前，美国的烟灰和绿烟灰曾在克罗地亚的低地地区被用来造林，并填补了窄叶灰（Fraxinus angustifolia Vahl）无法生存的洼地。在14个地点（0.03公顷圆形样地的系统样本）中研究了绿灰和窄叶灰的平均立木的生长。总共对212棵树进行了去核，并提取了11个横截面样品进行茎分析。曼恩·惠特尼（Mann-Whitney）U检验表明，在所有地点，窄叶灰和绿灰之间的径向生长在统计学上都存在显着差异。在粉煤灰中，该测试显示了最近20年和之前20年之间径向生长的统计差异。绿灰的特点是，前20-30年的年径向增长率非常高（高于平均水平），而其后一直被抑制在平均水平以下，仅约1.5毫米。较快的生长和较低的最终生长值所获得的结果表明，应以短的轮作期管理绿灰，因为这种重要的先驱物种旨在改善森林植被退化的那些地方的条件。

著录项

相似文献

  • 外文文献
  • 中文文献
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号