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Green spaces and urban green infrastructure are new concepts in urban planning, and lately, the influence of green spaces in cities and how this presence affects local climate change have been taken into account. Moreover, some of the ornamental trees most used in cities provoke allergic symptoms in sensitized people. Due to the importance the plane trees in our parks and cities have as ornamental trees, this article assesses the urban Platanus airborne pollen concentration in the air of five cities of the SW Iberian Peninsula and tries to determine the differential factors that its distribution has by means of combining continuous monitoring of the air using volumetric spore traps and the geolocation of plane trees. They were counted separately according to the direction (Q1 NE, Q2 SE, Q3 SW, Q4 NW) around the spore trap location in circles of 100, 200, 300, 400, 500, 1000, 1500, 2000 and 2500 m in diameter. Pollen sums were distributed according to the predominant wind direction for each day. The highest concentrations for Platanus pollen were recorded in Don Benito. Differences amongst pollen stations were found and were mainly related to their degree of maturity and their proximity to spore traps, and finally, with the number of plane trees. Furthermore, other factors, as the pruning, which is different in each city and even in a more local way, affects pollination and is frequently unknown to aerobiological studies. The geolocation of ornamental trees can be a useful tool for providing summarized information about their behavioral differences amongst cities, which can be used to create healthy itineraries, minimizing the natural hazards in human health (allergic diseases) and could be implemented into a model to help policy-makers to create measures to improve green urban development. 相似文献
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综述了土壤质量的概念及其研究进展,并探讨了土壤质量指标的选择原则,得出不同土壤的评价应以土壤的功能为基础并采用不同的标准。在以往研究中,人们一直强调以土壤物理、化学特性作为土壤质量指标。目前,国内外关于土壤生物学指标的研究日益增多,一些参数作为生物指标已表现出很大的潜力并成为系统稳定性的早期预警和敏感指标。之后阐述了国内外土壤质量指标空间变异的研究现状,探讨了该领域研究中存在的问题,展望了国内外土壤空间变异的研究前景。 相似文献
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Earthworms are being used as bio-indicators to assess terrestrial pollution. However, it is often not known whether their populations possess a uniform genetic structure, which would allow comparison of residues or biological properties of earthworms from different sampling locations. In order to investigate this point, random amplified polymorphic DNA (RAPD) variation was surveyed in earthworms (Lumbricus terrestris) from five different sampling sites in Germany. Forty oligonucleotide RAPD primers (10 base pairs in length) were screened, three of which produced high polymorphic band patterns. A total of 61 DNA fragments were detected in 90 individuals of L. terrestris from five sampling sites with 49 (80.3%) RAPD markers being polymorphic. The genetic similarities within (band sharing rates between 0.756 and 0.795) and among the L. terrestris populations (0.635) were similar even at widely separate locations. Inter-population variation in the RAPD pattern for all five earthworm populations accounted for 37.9% of the total variation, while intra-population variation for three adjacent Saarland populations accounted for only 18.0% of the total variation. Principal component analysis (PCA) and the genetic distances of the populations confirm these results. Twenty-four percent of the genetic distance is caused by geographical isolation as shown by a test for isolation by distance. These results show that L. terrestris fulfils the genetic qualifications for a bio-indicator particularly at closely located sampling sites. However, the results also suggest that earthworm studies of widely separated locations should include genetic characterisation of the earthworm samples. 相似文献
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为探讨赤子爱胜蚓谷胱甘肽(GSH)和丙二醛(MDA)含量变化对重金属污染土壤生态毒性的指示作用,在试验室模拟条件下,利用人工土壤和自然土壤,研究了重金属含量与蚯蚓GSH和MDA含量变化的剂量效应关系。结果显示,在人工土壤试验中,Cu可诱导蚯蚓GSH和MDA含量上升,暴露2 d、7 d、14 d后,Cu浓度与蚯蚓GSH含量的相关系数分别为0.556、0.807和0.775,与MDA含量的相关系数分别为0.760、0.672和0.544,均存在显著的剂量效应关系(p<0.05)。自然土壤试验结果显示,赤子爱胜蚓的GSH和MDA含量与土壤Cu全量的偏相关系数分别为-0.830(p<0.001)和-0.599(p<0.05),与Cd全量的偏相关系数分别为-0.697(p<0.05)和-0.690(p<0.05)。同时发现,赤子爱胜蚓GSH含量变化对土壤重金属响应的敏感性要高于MDA。 相似文献
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