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暖温带不同地区青檀形态特征分析 被引量:11
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作者 张川红 郑勇奇 +4 位作者 宗亦臣 吴超 郑健 焦明 薛新花 《林业科学研究》 CSCD 北大核心 2008年第5期737-740,F0003,共5页
Wild resources of Pteroceltis tatarinowii Maxim.were investigated and morphological characteristics of leaves,fruits and seeds were measured in 2005.In Lingyan Temple of Shandong,the trees grow in the temple and along... Wild resources of Pteroceltis tatarinowii Maxim.were investigated and morphological characteristics of leaves,fruits and seeds were measured in 2005.In Lingyan Temple of Shandong,the trees grow in the temple and along the roads.In addition to the two Pteroceltis tatarinowii,the average DBH and height of the other trees were 24.32 cm and 10.05 m respectively.The stands in Miaofeng Mountain distributed only in the valley of Dishuiyan with the average DBH of 16.12 cm and average height of 11.50 cm.Pteroceltis tatarinowii could naturally reproduce in wild habitat and only a few natural reproduced seedlings were found at Lingyan Temple.The results of variance analysis showed that there was significant difference of 9 characteristics among different individual trees of the same source.Except for width of fruit wing,8 morphological characteristics significantly differed among three sources.Significant difference exited in leaf length and leaf width among three sources.Although there was no significant difference in seed and nut features between two different sources in Beijing,those characteristics of Pteroceltis tatarinowii from Beijing source were obviously different with those from Shangdong.The seeds from Shandong were the smallest and lightest.There was distinctness in morphological quality characteristics from different trees. 展开更多
关键词 青檀 形态特征 地理变异
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农牧交错区退耕还林后土壤物理性状分析——以内蒙古乌兰察布市卓资县为例 被引量:1
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作者 王同顺 郭建英 +3 位作者 孙保平 李锦荣 王庆华 任正军 《福建林业科技》 2010年第1期17-21,共5页
以卓资县的退耕还林地为研究对象,探讨不同退耕还林地土壤物理性质的变化,初步研究结果表明:退耕还林8 a后,相同立地条件、不同林种间土壤毛管孔隙度和非毛管孔隙度差异极显著,而总孔隙度差异不显著;总体上退耕还林地土壤粘粒含量高于耕... 以卓资县的退耕还林地为研究对象,探讨不同退耕还林地土壤物理性质的变化,初步研究结果表明:退耕还林8 a后,相同立地条件、不同林种间土壤毛管孔隙度和非毛管孔隙度差异极显著,而总孔隙度差异不显著;总体上退耕还林地土壤粘粒含量高于耕地,其中0~20 cm增加不显著,20~40 cm、40~60 cm增加较多;除柠条林地外,其他林地土壤容重0~20 cm土层高于20~40 cm、40~60 cm土层。 展开更多
关键词 农牧交错区 退耕还林 土壤物理性质 卓资县
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