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对新乡市12种道路绿化树木叶片重金属铅、镉和锌的含量进行分析。结果表明,同种道路绿化树木叶片的重金属含量表现为污染区清洁区,不同树种道路绿化树木叶片的重金属含量具有明显差异,铅含量的大小排序为榆树栾树雪松刺槐悬铃木夹竹桃毛白杨柳树卫矛圆柏臭椿核桃;镉含量的大小排序为毛白杨雪松栾树悬铃木夹竹桃臭椿柳树榆树悬刺槐圆柏卫矛核桃,锌含量的大小排序为夹竹桃榆树臭椿柳树刺槐栾树雪松毛白杨核桃圆柏卫矛悬铃木。运用隶属函数法对12种道路绿化树木叶片重金属含量进行归类,榆树和栾树归为第1类,夹竹桃、雪松、毛白杨、刺槐、柳树、悬铃木和臭椿为第2类,卫矛、圆柏和核桃归为第3类。 相似文献
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河南中北部38个常见树种的生物量与固碳特征分析 总被引:1,自引:0,他引:1
《西部林业科学》2017,(1)
为了筛选出固碳能力较强的造林绿化树种,提高森林的碳汇功能,2014年8月,设置标准地114块,采用收获法测定了河南中北部常见的38个树种的地上与地下部分的平均生长量与含碳量,计算不同树种的固碳量,对不同树种的固碳量进行了聚类分析。结果表明,落叶阔叶乔木平均固碳量最大,其次为常绿阔叶乔木、灌木,针叶树最小。根据聚类分析结果可知,悬铃木固碳量最大,其次为107杨、泡桐、银杏、国槐、刺槐、楸树、苦楝等树种,火棘固碳量最低,建议在河南中北部造林绿化中优先选用悬铃木、107杨、泡桐、银杏、国槐、刺槐、楸树、苦楝。 相似文献
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为掌握人工诱导四倍体毛泡桐保持多倍体特性情况及毛泡桐截干再生特性,笔者以5a生四倍体及二倍体毛泡桐截干再生苗为材料,对截干再生苗的倍性、出芽数、生长速率、叶片特性、叶绿素含量及光合特性等进行研究.结果表明:四倍体毛泡桐截干再生苗能很好地保持其多倍体倍性,相对于二倍体来说,出芽数较少,生长较缓慢;气孔增大,气孔密度降低;... 相似文献
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株洲市几种常用绿化植物滞尘能力初探 总被引:5,自引:0,他引:5
对株洲市16个常用绿化植物滞尘能力进行测定,结果表明:阔叶乔木树种单位面积滞尘量为广玉兰>棕榈>大叶樟>香樟>杜英>栾树>枫香>悬柃木;阔叶灌木树种单位面积滞尘量为春鹃>红花檵木>红叶李>山茶花>珊瑚树>小叶女贞>十大功劳>桂花。 相似文献
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We determined the effects of short-term cultivation with various amounts of available nitrate nitrogen (NO3-) on NO3- use by woody shrub species. Nitrate concentration ([NO3-]) and nitrate reductase activity (NRA) were measured in leaves and roots of seedlings of Hydrangea hirta (Thunb.) Siebold, Lindera triloba (Sieb. et Zucc.) Blume and Pieris japonica (Thunb.) D. Don. Root [NO3-] increased with increasing NO3- supply in all species, whereas leaf [NO3-] remained low. There were significant correlations between [NO3-] in roots and leaves in all species, but no correlation was found between root NRA and leaf NRA. The low proportion of leaf NO3- assimilation to total NO3- assimilation in all species can be ascribed to the lack of NO3- transport from roots to leaves. In all species, root NRA increased with increasing NO3- supply until reaching a plateau. Species ranking based on maximum root NRA was H. hirta > L. triloba > P. japonica. Root NRA in P. japonica was low, even though root [NO3-] increased with NO3- supply, indicating that NO3- was not an effective N source for this species. The ranking also suggested that H. hirta depended more on NO3- as an N source than L. triloba. The increase in root NRA with increasing NO3- supply was greater in H. hirta than in L. triloba, possibly indicating that a change in NO3- availability has a stronger influence on NO3- use in H. hirta than in L. triloba. 相似文献
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Proportional limit of wood obtained from a load-time diagram during an impact bending test 总被引:1,自引:0,他引:1
We transferred the linear part of a load-deflection diagram from an impact bending test of wood into a load-time diagram. In addition, we proposed a method to obtain the proportional limit from the load-time diagram. Japanese cedar (Cryptomeria japonica D. Don), hondo spruce (Picea yezoensis Carr. var.hondoensis Rehd.), hiba arbor-vitae (Thujopsis dolabrata Sieb. et Zucc.), Japanese red pine (Pinus densiflora Sieb. et Zucc.), paulownia (Paulownia tomentosa Steud.), Manchurian ash (Fraxinus mandshurica Rupr.), and Japanese evergreen oak (Quercus acuta Thunb.) were used in this study. The dimensions of each specimen were 115mm (L) * 7mm (R) * 7mm (T). The results were as follows: (1) The linear region of the load-deflection diagram in the impact bending test could be transferred with sufficient accuracy to a load-time diagram using a sine function. (2) Approximating the load-time diagram by a linear equation was useful for obtaining the proportional limit. 相似文献
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通过对湖南省资兴市某已闭库并实施生态修复的铅锌尾矿库及周边受污染土壤和植物的采样分析,以ICP—ASE电感耦合等离子体发射光谱法测定了杉木、杨树、栾树、泡桐、香樟和乌桕等6种木本植物中Pb、Zn、Cu和Cd等重金属元素的含量,并运用转运系数和富集系数分析了植物相应的富集能力与转运特征。结果表明:6种植物中,对Pb富集系数最大的为乌桕,达到0.029;对Zn富集系数最大的为泡桐,达到0.374;栾树对Pb的转运系数达到1.314;泡桐对于Zn的转运系数达到1.452。6种植物均能适应铅锌重度污染的生长环境,其中乌桕、泡桐、栾树富集和转运Pb、Zn能力突出,适宜作为铅锌矿区植物修复的主要木本树种。 相似文献
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研究了泡桐(原变种)果实的化学成分。采用Sephadex LH-20柱色谱及薄层色谱等方法进行分离,从其70%丙酮提取物水溶性部分分离得到4种苯丙素苷化合物,经波谱分析及理化性质分析,化合物分别鉴定为:毛蕊花苷(1)、异毛蕊花苷(2)、campneoside II(3)和isocampneoside II(4)。化合物1和2首次从该植物中得到。抑菌活性试验结果表明,泡桐(原变种)果实中分离得到的苯丙素苷化合物、丙酮提取物、乙酸乙酯溶及水溶性部分具有较高的抑菌活性,其中,对革兰氏阳性菌中表皮葡萄球菌的抑制能力最强。 相似文献
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本项目研究抽取了济南南部山区具有典型植被群落特征的18个标准样地,通过对样地植被群落的调查,挖掘了山区植被群落恢复重建过程中存在的问题。在对植被群落类型、结构特征及生态功能分析基础之上,又研究了优势树种与其他物种的种间关系以及物种在群落中的地位,最后综合提出南部山区山体植被群落优化的5种植被搭配模式:(1)侧柏+黄栌-黄荆-羊胡子+日本乱子草;(2)黑松+黄榆-连翘-地榆+黄花菜+大丁;(3)侧柏+黄栌+桑-雀儿舌头-旋覆花;(4)黄连木+大叶白蜡+黑松-扁担木-茜草+委陵菜;(5)侧柏+刺槐+桑-黄荆-桃叶鸦葱+茜草+荩草; 相似文献