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12种园林植物耐荫性鉴定指标的筛选 总被引：2，自引：0，他引：2
在对遮荫条件下12种园林植物的生长增量、叶片厚度、比叶面积、叶片含水量、叶绿素a＋b含量、叶绿素a,b、类胡萝卜素含量、糖含量、过氧化物酶活性、日平均净光合速率、光补偿点、表观量子效率等生理生化指标测定基础上,对各项指标进行了主成分分析和逐步回归分析,结果表明生长增量、比叶面积、叶绿素a,b、过氧化物酶活性、目平均净光合速率等5个指标对植物的耐荫性有显著影响。采用所建立的最优回归方程对供试植物进行耐荫性预测及排序的结果与栽培试验观察结果相一致,表明这5个指标可作为快捷的植物耐荫性鉴定指标。 相似文献
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耐阴地被植物及其在园林中的应用 总被引：2，自引：0，他引：2
阐述了耐阴地被植物的概念及分类,并根据植物特点、习性和园林造景实例说明阴生地被植物在园林中的应用选择,为园林绿化工作者提供了参考依据。 相似文献
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较全面地报道厦门地区观赏地被植物62科129属166种(包括变种或品种),并探讨其在园林绿化中的应用。 相似文献
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调查了厦门地区棕榈科植物资源状况及其绿化应用,并结合多年来对厦门市园林植物园棕榈植物保育中心内棕榈科植物的物候期观察,选出适合厦门地区推广应用的棕榈科植物104种,同时对厦门地区棕榈科植物应用的种类、数量、分布以及应用频度等进行统计分析。 相似文献
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为高效筛选雨水花园适用植物,以香彩雀Angelonia salicariifolia等8种园林地被植物为试材,采用盆栽模拟涝渍的方法,研究不同时间淹水胁迫处理后8种植物的观赏性状及生理指标,通过主成分分析与隶属函数法对其耐涝性进行综合评价,并筛选评价植物耐涝性的有效指标。结果表明,8种园林地被植物的耐涝性强弱依次为香彩雀、水鬼蕉Hymenocallislittoralis、龙船花Ixorachinensis、朱槿Hibiscusrosa-sinensis、大花马齿苋Portulacagrandiflora、朱蕉Cordylinefruticosa、巴西野牡丹Tibouchinasemidecandra、四季海棠Begoniasemperflorens;植物叶片的相对含水量、MDA含量、相对电导率与Fv/Fm值是反映植物耐涝性的重要指标。 相似文献
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耐荫性是植物在低光环境下的生存和生长能力,对森林植物群落演替起重要作用,植物对遮荫的适应机制已成为生态学的研究热点.本文综述了森林植物的耐荫性及其在形态和生理方面的适应性,分析了森林植物在生长性状、生物量分配、树冠结构、叶片形态生理、叶片解剖结构、光合参数、碳水化合物分配、水分和养分的利用等方面对遮荫产生的可塑性响应,最后对目前研究存在的问题进行了分析,展望了未来的研究内容和方向. 相似文献
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描述了黄河三角洲地区耐盐乡土植物的种类及生态价值。黄河三角洲地区耐盐乡土植物以草本植物为主,灌木和乔木零星分布。主要耐盐乡土植物有芦苇、盐地碱蓬、柽柳和旱柳等。黄河三角洲地区耐盐乡土植物发挥着重要的生态作用,主要包括:防风固沙,保持水土,调节气候;固碳增汇,补偿碳排放;防治重金属等污染;净化水质;维持生物多样性;改良盐渍土。 相似文献
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在有20000个独立转化株系的拟南芥(Arabidopsis thaliana)激发标签突变体库中,筛选到1 株耐旱、耐盐突变体sdt1(high-salinity and drought tolerant 1)。实验结果表明在连续26d不浇水的干旱胁迫条件下,sdt1可保持正常生长而野生型全部萎蔫死亡。此外,在外施150 mmol/L NaCl水溶液的高盐胁迫条件下．sdt1可正常生长,而野生型全部死亡。在0．5xMS培养基上进行的发芽实验表明sdt1对内源和外施ABA的敏感性均低于野生型,为一个ABA不敏感突变体。对叶片失水率的测定结果表明,在干旱胁迫下sdt1的失水率显著小于野生型。Southern杂交结合sdt1的遗传分析表明该突变体为紧密相邻的2个T-DNA串联插入,对突变的功能基因有待进一步分子鉴定。 相似文献
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吉安市野生地被植物资源及其园林应用综合评价 总被引：1，自引：0，他引：1
罗毅 《中国野生植物资源》2012,31(1):73-77
通过对吉安市典型山地野生地被植物资源进行实地调查,在初步确定具有良好观赏价值的87种野生地被植物基础上,采用线性加权综合法数学模型对吉安市野生地被植物作了综合评价,重点推荐在吉安地区具有园林应用价值的野生地被植物5种,为野生地被植物的合理开发应用提供科学依据。 相似文献
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The aim of the study was to assess the potential importance for Mediterranean plants of trade-offs in the response to irradiance and water availability at the regeneration stage. Survival and growth patterns across an experimentally imposed irradiance gradient (1, 6, 20 and 100% sunlight) were studied in seedlings of eight Mediterranean woody species, together with the impact of a simulated summer drought. We found evidence of some of the trade-offs previously reported for non-Mediterranean plant communities, such as between survival in the shade and relative growth rate (RGR) at high light, but no evidence for others, such as between shade and drought tolerances. The impact of drought on survival and RGR was stronger in high light than in deep shade. The observed species-specific differences in performance provide a mechanistic basis for niche differentiation at the regeneration stage, contributing to possible explanations of species coexistence in Mediterranean ecosystems. 相似文献
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Surya K. Maharjan Milena Holmgren Frans Bongers Jan J. Wieringa William D. Hawthorne 《Biotropica》2011,43(5):552-561
Plant morphological and physiological traits affect the way plants tolerate environmental stresses and therefore play an important role in shaping species distribution patterns in relation to environmental gradients. Despite our growing knowledge on the role of functional traits in structuring plant communities, few studies have tested their importance at large scales in the wet tropics. Here, we describe the distribution patterns of the most important West African rain forest timber species along the regional rainfall gradient and relate them to their functional traits. We found that the distribution patterns of 25 out of the 31 studied species (80%) were significantly related to mean annual rainfall. Shade tolerance and drought resistance were identified as the main strategy axes of variation. Wood density and leaf deciduousness emerged as the best predictor traits of species position along the rainfall gradient, explaining respectively 32 and 15 percent of the variation. Species traits tended to show stronger relationships with estimated optimum annual rainfall for each species than to the extreme rainfall conditions where they occur. The significant role of rainfall in shaping timber species distribution and the strong relationships between species traits and rainfall indicate that changes in climate, especially declining rainfall, could have strong effects on species composition and abundance in these tropical forests. 相似文献
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Although it is widely recognized that climate change will require a major spatial reorganization of forests, our ability to predict exactly how and where forest characteristics and distributions will change has been rather limited. Current efforts to predict future distribution of forested ecosystems as a function of climate include species distribution models (for fine‐scale predictions) and potential vegetation climate envelope models (for coarse‐grained, large‐scale predictions). Here, we develop and apply an intermediate approach wherein we use stand‐level tolerances of environmental stressors to understand forest distributions and vulnerabilities to anticipated climate change. In contrast to other existing models, this approach can be applied at a continental scale while maintaining a direct link to ecologically relevant, climate‐related stressors. We first demonstrate that shade, drought, and waterlogging tolerances of forest stands are strongly correlated with climate and edaphic conditions in the conterminous United States. This discovery allows the development of a tolerance distribution model (TDM), a novel quantitative tool to assess landscape level impacts of climate change. We then focus on evaluating the implications of the drought TDM. Using an ensemble of 17 climate change models to drive this TDM, we estimate that 18% of US ecosystems are vulnerable to drought‐related stress over the coming century. Vulnerable areas include mostly the Midwest United States and Northeast United States, as well as high‐elevation areas of the Rocky Mountains. We also infer stress incurred by shifting climate should create an opening for the establishment of forest types not currently seen in the conterminous United States. 相似文献
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对2012年珠三角河网浮游植物物种丰富度的时空特征进行了系统阐析。季节上,枯水期的物种丰度差异大,丰水期差异小;空间上,广州周边及河网中部个别站位的总种数高于其他站位。不同季节的空间特征显示,枯水期的物种丰度自西江沿线、河网中部、广州周边呈递增趋势;而丰水期呈现三角洲两侧的物种丰富度高于河网中部。各类群相对组成结果显示,硅藻在枯水季节占绝对优势,丰水期优势下降;空间上广州周边站位硅藻百分比明显低于其他站位。分析原因,径流相关的补充和稀释作用和水体搅动引起的底层藻类的悬浮补充不仅影响物种丰富度的季节变动,也影响不同类群的相对组成;水体交换能力和营养盐分别是决定丰水期和枯水期物种丰富度空间分布的关键因素。 相似文献
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Yannek Kber Peter Meyer Jonas Stillhard Emiel De Lombaerde Jürgen Zell Golo Stadelmann Harald Bugmann Christof Bigler 《Ecology and evolution》2021,11(17):12182
- Tree regeneration is a key process for long‐term forest dynamics, determining changes in species composition and shaping successional trajectories. While tree regeneration is a highly stochastic process, tree regeneration studies often cover narrow environmental gradients only, focusing on specific forest types or species in distinct regions. Thus, the larger‐scale effects of temperature, water availability, and stand structure on tree regeneration are poorly understood.
- We investigated these effects in respect of tree recruitment (in‐growth) along wide environmental gradients using forest inventory data from Flanders (Belgium), northwestern Germany, and Switzerland covering more than 40 tree species. We employed generalized linear mixed models to capture the abundance of tree recruitment in response to basal area, stem density, shade casting ability of a forest stand as well as site‐specific degree‐day sum (temperature), water balance, and plant‐available water holding capacity. We grouped tree species to facilitate comparisons between species with different levels of tolerance to shade and drought.
- Basal area and shade casting ability of the overstory had generally a negative impact on tree recruitment, but the effects differed between levels of shade tolerance of tree recruitment in all study regions. Recruitment rates of very shade‐tolerant species were positively affected by shade casting ability. Stem density and summer warmth (degree‐day sum) had similar effects on all tree species and successional strategies. Water‐related variables revealed a high degree of uncertainty and did not allow for general conclusions. All variables had similar effects independent of the varying diameter thresholds for tree recruitment in the different data sets.
- Synthesis: Shade tolerance and stand structure are the main drivers of tree recruitment along wide environmental gradients in temperate forests. Higher temperature generally increases tree recruitment rates, but the role of water relations and drought tolerance remains uncertain for tree recruitment on cross‐regional scales.
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区域景观生态安全是生态安全的重要组成部分,对于国家安全和社会可持续发展具有重要影响。以1990年和2005年珠江三角洲Landsat5TM和Landsat7ETM+遥感数据为基本数据源,选取聚集度、景观破碎度、景观形状指数、Shannon多样性指数,并构建了景观脆弱度指数和景观安全邻接指数,对研究区景观空间格局变化进行对比分析。在此基础上,利用基于遗传算法的投影寻踪方法,计算景观生态安全指数,评价研究区的景观生态安全状况。结果表明:(1)从1990年到2005年,珠江三角洲9市的聚集度、破碎度、景观形状指数和Shannon多样性指数变化不大,而景观脆弱度和景观安全邻接指数变化显著,9市的景观脆弱度都呈现减少趋势,而9市景观安全邻接指数都呈增加趋势。(2)从1990年到2005年,珠海和惠州两市景观生态安全状况一直保持良好,而东莞和中山两市的景观生态安全值一直较低;除佛山和广州两市景观生态安全状况略有提高外,其它7市景观生态安全值都有一定程度的减小,其中以肇庆市降低最多。珠江三角洲地区经济高速发展,人为活动剧烈,利用投影寻踪方法构建景观生态安全指数,评价高强度发展区域的景观生态安全状况是有效、可行的。 相似文献