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对天津市4个不同地点(昆仑桥、水上公园、杨柳青庄园和市区空旷地)林木的空气负离子浓度日变化和年变化进行测定,并分析了空气温湿度等环境因素对其影响。结果表明:空气负离子浓度日变化基本呈先增大而后减小的趋势,其最大值多出现在中午左右,不同地点略有不同;空气负离子浓度季节变化趋势基本为夏季春季秋季,最大值出现在7月;不同地点空气负离子浓度变化趋势与温湿度变化趋势一致,呈正相关关系;水上公园的空气质量最清洁,市区空旷地质量最差。林木可以提供空气负离子,从而达到净化空气的目的,有利于身体健康。因此,城市建设中应加强植被绿化。 相似文献
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通过对临安市3个新建居住区绿地植物群落多样性现状的调查,分析样地内植物的组成、群落的层次结构特征、生物多样性,以及居住区园林植物群落多样性存在的问题,得出结论:从群落的多样性角度来看,Simpson指数:林水山居>春天小区>筑境小区,林水山居的植物种类最为丰富,乔灌草的搭配也比较合理。从生态效益评价来看,负离子浓度是评价空气质量的重要指标,所测数据表明,在外界影响因素相同的情况下,湿度越高,空气负离子浓度越大,生态效益也相对较好,负离子浓度春季要高于冬季,整体上春天小区>林水山居>筑境小区,3个居住区的空气清洁程度都为清洁。根据对临安居住区绿地植物群落结构的调查结果,提出群落优化改造建议。 相似文献
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对长兴县三种功能类型森林绿地空气负离子浓度进行测定,结果表明:城郊森林绿地的空气负离子浓度为1 823个/cm~3,城区公共绿地为1 296个/cm~3,单位、居住区绿地为958个/cm~3;在森林植物生长期间,空气负离子浓度从城区向城郊呈增加趋势;在郊区以高大乔木为主的近自然林,空气负离子浓度高,生态效应明显。综合上述分析,本文提出应按照近自然森林群落建设理念,推广种植乡土树种、乔木树种,营造城区核心林地,改善城市生态环境,提高城镇居民的生活品质。 相似文献
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城市风景园林植物多样性及空气净化效应研究 总被引：1，自引：0，他引：1
城市化已经成为人类社会发展的必然趋势,而建设生态园林则是城市发展的必由之路。现在上海、杭州、河南新乡3座城市设置样地,调查样地内的植物多样性、气温、空气相对湿度、风速、空气负离子浓度等指标,通过与对照裸地的各项生态因子数据对比,研究风景园林植物的多样性、群落结构等对部分空气质量评价指标的影响。结果表明:不同类型植物群落中植物多样性高低顺序为乔灌草灌草草。降低气温、增加空气相对湿度、降低风速、增加空气负离子浓度的能力同样是乔灌草灌草草。生态园林植物多样性的提高有利于更好的发挥其改善城市生态环境的作用,为生态园林建设中植物的合理配置提供了参考依据,为今后城市园林更好的发挥其生态效益提供了科学建议。 相似文献
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《北方园艺》2020,(11)
以木香薷为试材,对开花进程中、一天中不同时间及仪器进气口距植株顶部不同高度处的空气负离子、PM_(2.5)浓度、气象因子进行测定,以期探究芳香植物木香薷群落负离子及PM_(2.5)浓度的时空变化特征及其影响因素。结果表明:开花进程中木香薷群落负离子浓度由低到高的变化顺序依次为初花期盛花期末花期;开花进程中PM_(2.5)浓度由高到低依次为初花期盛花期末花期;木香薷群落负离子浓度的最高值出现在17:00,最低值出现在15:00;PM_(2.5)浓度最高值出现在11:00,最低值出现在17:00;仪器进气口距植株顶部15 cm处空气负离子浓度高于45 cm处的浓度,二者相差90.5 ion·cm~(-3),而不同位置处的PM_(2.5)浓度差值仅0.6μg·m~(-3),即群落负离子浓度受位置变化影响较大,PM_(2.5)浓度则受影响较小;木香薷群落负离子浓度与温度、光照强度均呈极显著负相关,而与湿度呈极显著正相关,且直线回归表明负离子浓度与各气象因子的相关性从强到弱依次为湿度温度光照强度;PM_(2.5)浓度与温度呈显著负相关,与湿度、光照强度均呈正相关,且与湿度的相关性达到极显著水平。 相似文献
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以冀北山地华北落叶松人工林与油松天然次生林为研究对象,对不同坡位气象因子、立地因子等方面的差异进行研究.结果表明:华北落叶松人工林内测定点温湿度均高于油松林,同一林分内温度差异不显著.落叶松林内照度随着海拔增加逐渐增大,油松群落内坡底照度最高.油松、落叶松群落随着海拔的增加,各样地相同土层间土壤质量含水量、饱和含水量、相对含水量逐渐减小,相同海拔落叶松林样地各土层水分指标均高于油松林.油松各样地内土壤容重随着土层深度的增加而增加,且随着海拔的增高,各样地相同土壤层次容重值增大.落叶松林变化均不显著.油松各样地土壤孔隙随着土层深度和海拔的增加均变小.落叶松林变化均不显著,但在相同土层上落叶松林土壤孔隙多于油松林.油松林地土壤颗粒随着土层深度的增加而减小,落叶松林则增大.油松及落叶松群落坡中样地土壤颗粒均较大.2个林分土壤pH随着土壤层次的增加而增加,土壤养分含量随土层深度增加而递减;随着海拔增高,相同海拔落叶松林内有机质、全氮、全磷、碱解氮、有效钾含量均高于油松林,而速效磷则相反. 相似文献
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空气中的负离子被誉为"空气维生素",其浓度水平是评价一个城市空气质量的重要指标之一。由于大气中的负离子浓度与当地气象条件有着直接关系。研究大气负离子浓度的变化规律及其与周围各种环境要素的相关关系,有利于为人们的日常生活和生产活动提供参考,为生态建设的绿化结构和植物配置提供参考。 相似文献
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Context
Eco-environmental effects of urbanization are a focus in landscape ecology.Objective
The influences of population, economic and spatial development during the urbanization process in Beijing City, China on net primary productivity (NPP) were analyzed. The responding mechanism of NPP in different urbanization stages was also examined to develop advice about eco-environmental sustainability of urban development.Methods
Using the Carnegie Ames Stanford Approach model, we estimated NPP. Using linear regression and polynomial regression analysis, we analyzed NPP responses to stages of urbanization.Results
High NPP areas were located in northeast Yanqing, northwest Miyun, northern Huairou and Pinggu. The distribution of NPP generally occurred in the following order from high NPP to low NPP: outer suburbs, inner suburbs, encircled city center, and inner city. Because of the heat island effect in winter, the estimated NPP in the encircled city center and inner city was higher in 2009 than in 2001. There was a negative correlation between NPP and both economic and spatial urbanization, but an increase in population did not necessarily lead to an immediate decrease in NPP. An analysis of NPP dynamics in five kinds of urban development zones showed that urbanization resulted in a lasting and observable loss of NPP over time and space, although there was some promotion of NPP in highly urbanized zones.Conclusion
There are three stages in the response of NPP to urbanization: damage stage, antagonistic stage, and coordination stage. The stage threshold depends on local eco-environmental management and urban planning interventions.14.
Currently, the increasing frequency of inhalant allergy is often linked to the urbanization effect. The pollen forecasts for a given city are most often prepared using data from one aerobiological station. However, there is evidence that the pollen concentrations in the air might differ depending on the city area and the height of the pollen trap. This study evaluated the spatial differences in the daily concentrations of alder and birch pollen grains in an urban area in relation to the proximity of the pollen sources and meteorological parameters. Pollen grains were sampled in Rzeszów in 2014–2016 by three volumetric traps located at the roof and nose levels in two city areas that differed in the numbers of alder and birch trees. The daily pollen concentrations were categorized into three allergy symptom thresholds. The relationship between the daily pollen concentrations and meteorological variables was examined using a redundancy analysis and circular statistics. There were spatial differences in the pollen season intensity and, to a lesser extent, the variability in its course. Generally, higher concentrations were registered at the roof level and in the city suburbs than at the nose level and in the downtown area where alder and birch trees were less numerous. Despite the spatial variability of the pollen concentrations and the differences in the proximity and abundance of pollen sources, the risks for allergy sufferers were similar throughout the city. It was concluded that the main cause of this phenomenon is the high dispersal abilities of Alnus and Betula pollen grains. Although temperature seems to be a crucial factor that influences the airborne pollen of both taxa, several weather variables were found to have complex impacts on the daily concentrations. 相似文献
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Light and atmospheric pollution affect photosynthesis of street trees in urban environments 总被引：1，自引：0，他引：1
The gas exchange of leaves of the Ilex rotunda trees planted at thirteen sites in the city of Fukuoka, Japan, with various sun light conditions and air pollutant concentrations was studied. The highest maximum photosynthetic rate and the stomatal conductance of single leaves were measured under controlled conditions and analyzed with the environmental variables by correlation analysis. The photosynthetic rate of the urban core was highest and that of the suburban area was lowest. The results from the correlation analysis showed that the photosynthetic rate was negatively correlated with sun light conditions and positively correlated with air pollutant concentrations. The reasons for the higher photosynthetic rate in the urban core with poor sun light condition and higher air pollutant concentrations were discussed in relation to stimulation by air pollutant and avoidance of photoinhibition. 相似文献
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Jo-Anne E. Cavanagh Peyman Zawar-Reza J. Gaines Wilson 《Urban Forestry & Urban Greening》2009,8(1):21-30
Of interest to researchers and urban planners is the effect of urban forests on concentrations of ambient air pollution. Although estimates of the attenuation effect of urban vegetation on levels of air pollution have been put forward, there have been few monitored data on small-scale changes within forests, especially in urban forest patches. This study explores the spatial attenuation of particulate matter air pollution less than 10 μ in diameter (PM10) within the confines of an evergreen broadleaved urban forest patch in Christchurch, New Zealand, a city with high levels of PM10 winter air pollution. The monitoring network consisted of eight monitoring sites at various distances from the edge of the canopy and was operated on 13 winter nights when conditions were conducive for high pollution events. A negative gradient of particulate concentration was found, moving from higher mean PM10 concentrations outside the forest (mean=31.5 μg m?3) to lower concentrations deep within the forest (mean=22.4 μg m?3). A mixed-effects model applied to monitor meteorological, spatial and pollution data indicated temperature and an interaction between wind speed and temperature were also significant (P?0.05) predictors of particulate concentration. These results provide evidence of the potential role that urban forest patches may play in mitigating particulate matter air pollution and should be considered in plans for improving urban air quality. 相似文献
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以美人蕉(Canna glauca)和萍蓬草(Nuphar pumilum)为试材,采用盆栽法,研究了不同浓度EM菌肥(1 000、2 000、4 000、8 000倍液)对铜尾矿渗出液中植物生长及Cu离子富集的影响,以期为EM菌肥实际应用于修复和治理矿区废弃尾矿渗出液水质及植物筛选提供依据。结果表明:在铜尾矿渗出液胁迫下,EM菌肥处理下美人蕉幼苗叶数、根数均大于对照;高浓度EM菌肥对美人蕉和萍蓬草株高均有抑制作用,而低浓度对2种植物的根长有促进作用。在不同浓度EM菌肥处理下美人蕉幼苗耐性指数均高于对照,萍蓬草则表现出低浓度EM菌肥处理耐性指数大于对照。在4 000倍液浓度下美人蕉地上部Cu离子含量最高,是对照的1.16倍,而地下部Cu离子含量在4 000倍液时最低。EM菌肥一定程度上促进了美人蕉地下部Cu离子向地上部转移。添加不同浓度EM菌肥一定程上均促进了2种植物对Cu离子的富集,对萍蓬草的促进程度高于美人蕉。 相似文献
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为了探讨屋顶绿化的生态效益,2013年7月选取重庆市园林事业管理局花园式屋顶绿化作为研究对象,以无绿化植物的屋顶水泥地作为对照,进行“乔-灌”、“灌-草”和草坪三种不同植物配置模式的气温、空气相对湿度、地表温度和空气中负氧离子含量测定。研究结果表明,屋顶绿化具有重要的生态效益,且不同植物配置模式的生态效益有较大差异。降温幅度为“乔－灌”（3．60℃）〉“灌～草”（2．68℃）〉草坪（1．43℃）,增湿幅度为草坪（29．42％）〉“乔-灌”（17．68％）〉“灌-草”（9．46％）,对地表温度的降低程度“乔－灌”（25．55℃）〉草坪（20．67℃）;屋顶绿化空气负氧离子含量此对照高33．73ions／m^3。 相似文献