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1.
城市不同绿地结构对空气负离子水平的影响   总被引:10,自引:0,他引:10  
穆丹  梁英辉 《生态学杂志》2009,28(5):988-991
选择佳木斯市具有代表性的绿地作为对象,对不同结构绿地的空气负离子水平进行了测定。结果表明:不同结构绿地的空气负离子水平差异极显著,以乔灌草复层结构绿地空气负离子水平最高,空气质量最佳;城市不同结构绿地空气负离子浓度大小、空气质量优劣的排序均为乔灌草结构>乔草结构>灌草结构>草坪。  相似文献   

2.
该指标系统规定了空气生境指数(Air entironment index,简称AEI)、生境空气质量分级、采样点及取值时间,采样与分析方法及数据统计的有效性规定。空气生境指数(AEI)的测定与评价的十个项目:空气洁净度(CI)、空气新鲜度(T)、植物精气浓度、人均绿地面积、绿地植物覆盖率、硬质覆盖率、水体覆盖率、界外植物覆盖率、移植植物树龄或原生植物树龄、植物种类和植物景观。本手册适用于住区生境空气质量评价。住区生境空气质量分为五级:5A级空气质量住区;4A级空气质量住区;3A级空气质量住区;2A级空气质量住区;1A级空气质量住区。  相似文献   

3.
空气负离子具有杀菌、降尘、清洁空气和对人体多种疾病具有抑制、缓解和辅助治疗作用,是重要的生态旅游资源。采用美国Alphalab公司生产的AIC1000型空气离子测量仪,对各旅游景区的空气离子含量进行调查测定表明,山岳型旅游区的瀑布下、溪流河谷地带以及海滨、湖滨旅游区空气负离子浓度高,空气质量特优,是建设品氧谷,开展生态旅游的最佳场所。在溶洞洞穴内和高海拔旅游区,空气负离子浓度也高。旅游区空气负离子浓度夏秋季节高,冬春季节低,同时与天气变化也有关系。为了在生态旅游中更好地利用空气负离子资源,在旅游区游道设计,生态休闲度假地选址和生态品氧谷建设等方面,要充分开发空气负离子资源。在城市或大型旅游接待中心,喷泉则能显著提高周围环境中空气负离子浓度,改善空气质量。  相似文献   

4.
聊城市空气微生物污染的检测及评价   总被引:3,自引:0,他引:3  
采用平皿沉降法对聊城市空气微生物浓度进行了初步测定.结果表明:空气中细菌、霉菌的浓度分别为3.98×103cfu/m3、0.90×103cfu/m3,空气质量处于微污染水平;从功能区划分看,商业区、主要交通区细菌污染较重,商业区及休闲娱乐区以霉菌污染为主.  相似文献   

5.
我组织了生物兴趣小组的同学 ,对本校学生宿舍的方位、结构及其宿舍内空气中的细菌进行了调查与检测。1 材料和方法通过测定空气中的细菌总数来检测空气质量状况 ,本检测采用自然沉降法取样 ,随机抽样 ,先计算出每个样点培养皿菌落数的多少 ,然后求其平均值。1.1 大豆琼脂培养基的制作 在量杯中放入 10 0 g大豆 ,加入足量的水浸泡过夜 ,再用 15 p的压力蒸煮 1h,用 8层纱布过滤 ,取其滤液 ,补足水分至 10 0 0 m L,加入琼脂 15 g,加热充分熔化。分装到内径为 9cm的培养皿中 ,每皿约 15 m L,盖上皿盖 ,小心地平放到高压灭菌锅内 ,用 15 p的…  相似文献   

6.
城市街道空气污染物扩散模型综述   总被引:2,自引:0,他引:2  
城市街道是城市居民的活动场所,其空气质量与居民健康密切相关.空气污染扩散模型是模拟和评估街道空气质量的重要方法,近年来广受关注,但模型应用存在问题,亟待解决.本文介绍了4种常用的空气污染物扩散模型:ENVI-met、FLUENT、MISKAM和OSPM.通过工作原理、运算流程、时空分辨率等的对比分析,明确了各模型的适用范围及其对街道峡谷内空气质量模拟能力的差异,阐述了各模型在时间尺度、物理建模、天气模拟、湍流模拟及光化学污染方面处理能力的局限性,提出了模型优化途径.通过综合分析4种模型的研究案例,总结了模型应用中存在的问题,提出未来研究可以通过激光雷达等新技术提高模型参数的获得精度,并强调综合模拟污染效应与热效应等对评估城市街道空气质量的重要性.  相似文献   

7.
空气质量公报   总被引:3,自引:0,他引:3  
空气质量公报是对城市空气质量状况进行评价,并以空气污染指数的表征形式向公众发布。空气质量公报新增加空气质量的透明度,使城市居民了解所处城市的空气质量,提高市民对环境保护的监督意识和参与意识,加大对环境污染的治理力度,推动环保工作尽快与国际接轨。空气质...  相似文献   

8.
闫利  胡纹  尹名强 《应用生态学报》2020,31(11):3786-3794
空气中污染物及病菌的浓度直接影响人类健康。在污染源不变的情况下,有效通风决定了空气质量的优劣。因此,建立有效通风的定量判定指标,并利用此指标对特定区域空气质量进行实时评价,引导居民选择健康的室外活动场所成为迫切需要解决的问题。本研究采用雷诺平均Navier-Stokes(RANS)方法建立了基于计算流体力学(CFD)技术的城市空气污染模拟系统,研究了风速、污染物浓度和污染物扩散效率之间的关系。在此基础上,借助实时气象数据,对城市广场空间不同时段进行了风场模拟及空气质量评价。结果表明: 行人高度(1.5 m)空气中污染物有效扩散的临界风速值为1.0 m·s-1,此指标可作为某一具体区域空气质量评价标准。参照此判定指标,链接实时天气系统,通过模拟得到的行人高度风速分布,可实时、可视化地显示该场所空气质量优劣分布,实现公平、效率、合理地利用城市空间资源,为人们选择健康的室外活动场地提供指引,为公众疾病预防和健康促进提供技术和手段。  相似文献   

9.
田菁胶的细胞定位和粘度的关系   总被引:3,自引:0,他引:3  
对发育过程中和成熟的田菁(Sesbania Canabina)种子内胚乳细胞进行了透射和扫描电镜观察。结果表明:田菁胶形成后不是分泌到胞外,而是聚积在胞内,对不同粒度田菁胶的粘度测定,表明粒度越大,粘度越小;反之,粒度越大。这种结果与田菁胶在细胞内定位是相一致的。另外,对不同粒度田菁胶的糖和不熔物含量也进行了测定。  相似文献   

10.
国家重点生态功能区县域环境空气质量时空变化分析   总被引:2,自引:0,他引:2  
评估国家重点生态功能区县域空气质量改善状况,对落实国家生态文明建设与重点生态功能区转移支付制度具有现实意义。以国家重点生态功能区转移支付县域空气质量为评价对象,基于2015年至2019年的空气质量监测站点日均值数据,对环境空气质量状况和变化进行了评价分析。研究结果表明:国家重点生态功能区转移支付县域空气质量总体表现较好且仍在稳步提升,转移支付政策对2015—2019年国家重点功能区空气质量的改善有着明显的推动作用。优良天数比例超过90%的县域占比由2015年的33.77%提高到2019年的69.52%,水源涵养区的优良天数占比由2015年的72.71%提高到2019年的92.09%,空气质量改善效果最为显著。2015—2019年间,细颗粒物(PM2.5)污染占比明显下降,臭氧(O3)污染占比大幅上升,主要超标污染物由颗粒物逐渐转为颗粒物和臭氧。当前防风固沙区的主要超标污染物为可吸入颗粒物(PM10)和细颗粒物,其他三类生态功能区为细颗粒物和臭氧。重点生态功能区的空气质量存在着显著的空间差异,空气污染表现出显著的空间聚集特...  相似文献   

11.
The purpose of this study was: (i) to characterize the school indoor environment; (ii) to evaluate self-reported prevalence of disease symptoms among Portuguese teachers; and (iii) to evaluate, as far as we know for the first time in Portugal, the impact of the indoor air quality of schools on the prevalence of disease symptoms among teachers. The study was performed in the city of Oporto, starting in 2004; it included the analysis of questionnaires fulfilled by schoolteachers (n = 177), walkthrough surveys of schools grounds, buildings, and individual classrooms (n = 76), as well as indoor air monitoring. Respirable particle increase was related to chalk use and CO2 concentrations widely exceeded reference values. Schools located near traffic lines presented higher benzene and toluene concentrations. The guideline for total viable microorganism concentration was exceeded in 35.6% of classrooms. Significant increases in disease symptoms among teachers could be related to poor indoor air quality, which was mainly due to inefficient ventilation and influence of traffic emissions. Statistically significant correlations were found between central nervous system injuries and the levels of CO2 and total volatile organic compounds, and between upper respiratory problems and mucosal irritation and the levels of TVOC and respirable particles.  相似文献   

12.
Scientific evidence associates indoor environment pollutants with respiratory effects (asthma and allergies), and children constitute one of most sensitive groups. Indoor air quality (IAQ) in schools may indeed be a significant health factor for children, with effects on school attendance and performance. Our aim was to characterize IAQ of classrooms in Maia County (north of Portugal) for which there was no information available. The study was conducted in 21 of the 40 primary schools, selected by stratified random sampling. Depending on the dimension, one or two classrooms were tested at each school. Walkthrough surveys of school grounds, buildings, and individual classrooms were done. Continuous measurements were taken of temperature, relative humidity, airborne respirable particles, total volatile organic compounds, and carbon dioxide, whereas bioaerosols were counted on Plate Count Agar during regular school activities. The indoor arithmetic mean for PM10, CO2, TCOV, and bioaerosol concentrations were 0.14 mg/m3, 999 ppm, 0.41 mg/m3, and 4140 UCF/m3, respectively. The values of PM10 and CO2 were close to their acceptable maximum values, but bioaerosols were much higher. This study supports previous studies conducted in school environments and emphasizes the need for proactive indoor air quality audits in school buildings.  相似文献   

13.
赵秀玲  李伟  王伟民  韩立建  周伟奇 《生态学报》2020,40(17):5894-5903
目前国内外许多城市面临严重的空气污染问题,严重制约城市发展、影响人体健康。同时,部分城市(如深圳)空气质量已经达到并保持在良好的水平。探究这些城市空气质量演变过程及其调控,可为我国大量仍面临严重空气污染问题的城市提供参考和借鉴。以深圳市为案例,利用环境质量公报数据和统计年鉴数据,通过分析多个社会经济因子与典型污染物的相关关系,探究其空气质量演变特征与调控经验。结果表明,深圳市各类型空气污染物与城市社会经济发展均符合EKC模型假说,但不同污染物所处阶段不同。颗粒物、SO2和NO2均处于下降阶段,而O3目前处于高水平平稳阶段。总结深圳市空气质量改善历程及调控措施,发现主要有两大方面:宏观上严格把控;微观上精准治理。宏观上,重点放在产业结构和能源结构的快速调整上,对于空气质量的改善起到了非常明显的作用。而在微观精细化的管理上,对于空气污染的治理政策要具有持续性、精准性和及时性。当下,针对首要的O3污染问题,深圳市应重点关注城市人为排放VOCs和植物释放VOCs对O3生成的影响,以及城市热环境对O3浓度的影响。  相似文献   

14.
Summary A technical approach, in terms of air quality, implies the review of all components within the air conditioning system and the check of their characteristics, as far as contamination sources are concerned. The contribution introduces the parameters to be examined and specifies the importance of validation.  相似文献   

15.
Urbanized areas are struggling with the problem of air pollution and as the number of people living in cities is increasing, the situation is likely to deteriorate. One of the most harmful pollutants is particulate matter (PM). Increased levels of PM in the atmosphere are likely to have a negative impact on human health. Phytoremediation technology could be a solution. It involves plants acting as bio-filters by accumulating particles on, and in the leaves, thus removing the particles from the atmosphere. This study investigates the accumulation of PM including heavy metals (HMs) and polycyclic aromatic hydrocarbons (PAHs), on the foliage of small-leaved lime (Tilia cordata Mill.) in five Polish cities. There were significantly different PM amounts found in the trees between the cities which related to the different quantities of PM in the atmosphere at these cities. Significant differences were found between cities for the amounts of the different particulate size fractions, and the HMs and PAHs in leaves. Strong winds reduced the amount of PM on leaves, especially the smallest fractions, but no relationship with precipitation was found. The results suggest that T. cordata improves the air quality in cities and can be used as an effective bioindicator for PM air pollution.  相似文献   

16.

1. 1. Problems with regard to the relationship between energy conservation and indoor air quality in buildings are discussed with a brief history of legislation and practices in Japan since the oil crisis in 1973.

2. 2. In spite of energy conservation as widely advocated the sick building syndrome has hardly been manifested in most of the office spaces in Japan owing to the Law on the Assurance of Healthy Conditions in Buildings which enforced CO2 concentration to be kept lower than 1000 ppm.

Author Keywords: Indoor air quality; energy consumption; CO2 concentration; air conditioning; building  相似文献   


17.
It is known that regular aerobic exercise enhances cognitive functions and increases blood insulin-like growth factor 1 (IGF-1) levels. People living in urban areas spend most of their time indoors and indoor air quality can affect health. We investigated the effects of aerobic exercise in poor and good air quality environments on hippocampus and prefrontal cortex (PFC) neurons, anxiety, and spatial learning and memory in adolescent mice. Poor air quality impaired spatial learning and memory; exercise did not affect learning or memory impairment. Exercise in a good air quality environment improved spatial learning and memory. Poor air quality increased apoptosis in the hippocampus and PFC. Both exercised and sedentary groups living in a poor air quality environment had lower serum IGF-1 levels than those living in a good air quality environment. Living in a poor air quality environment has negative effects on the hippocampus, PFC and blood IGF-1 levels in adolescent mice, but exercise did not alter the negative effects of poor air quality.  相似文献   

18.
Air pollution is one of the top environmental concerns and causes of deaths and various diseases worldwide. An important question for sustainable development is to what extent urban design can improve or degrade urban air quality. In this article, we explored the relationship between ground-based observations of air pollution and urban form in the Yangtze River Delta (YRD), the largest metropolitan region in China. We analyzed six criteria pollutants (SO2, NO2, PM10, PM2.5, CO, O3) and summarized metric (air quality index, AQI) from 129 ambient air quality monitoring stations during 2015. Urban form was characterized using six spatial metrics, including the size, shape, regularity, fragmentation and traffic coupling factor of urban patches, based on satellite-derived land cover data. The results indicated that: (1) PM2.5, PM10 and O3 were three primary pollutants in the YRD. The annual average AQI was 79, and the air quality was “moderate” for human health, with the highest and lowest AQI appeared in winter (107) and summer (60). Moreover, the air quality of the southern areas (Zhejiang province, AQI: 68) was generally better than the northern parts (Jiangsu province, AQI: 86). (2) Through the size and shape of urban patches, urban form had a significant effect on urban air quality in the YRD. PARA_MN (Mean Perimeter-area ratio), ENN_MN (Mean Euclidean Nearest Neighbor Distance), CA (Total Urban Area) and NP (Number of urban patches) had the most significant impacts on air quality. PM10 and PM2.5 were two important pollutants highly positively related to CA and NP, while negatively related to PARA_MN and ENN_MN. In addition, the polycentric urban form was associated with high air quality. (3) Land use configuration was an important indicator to describe the urban air quality. When buffer distance of spatial scale was 25 km, air quality showed the highest correlation with forest coverage. A high forest coverage rate contributed to the better air quality, increasing or preserving the forested areas would help mitigate the air pollution.  相似文献   

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