Variation in concentrations of the airborne particulate matters(PM)in three kinds of typical recreation forests in Baiwang Mountain,West Mountain area of Beijing were observed day and night in spring.Results showed th...Variation in concentrations of the airborne particulate matters(PM)in three kinds of typical recreation forests in Baiwang Mountain,West Mountain area of Beijing were observed day and night in spring.Results showed that:1)Diurnal variations of PM concentrations in three kinds of typical recreation forests in West Mountain of Beijing area in spring were all synchronous.Curves of diurnal variation of PM concentrations had two peaks and two vales,and two peaks presented at 7:00-9:00 and 21:00-1:00,and two vales presented at 15:00 and 3:00-5:00 respectively.In addition,the larger proportion finer particles took the heavier total particles were in a day;2)Comparatively,peaks in day and vales at night of finer particles presented earlier than that of coarser particles,however the peaks at night were later;3)Weather conditions had influences on PM,and the finer particles were more sensitive to the conditions than the coarse particles.In general,PM concentration was higher at the state of low air temperature,high air relative humidity and soft wind.They also increased at cloudy night,especially for finer particles.展开更多
调查了神东矿区23个单位附属绿地的绿化结构,测定并评价了绿地的各种功能效益和蒸腾耗水量,最后选择绿地持续稳定、功能效益、蒸腾耗水量、整体美景度4个方面10个指标,用主成分分析法综合评价了不同绿地配置模式的优劣顺序,筛选出较好...调查了神东矿区23个单位附属绿地的绿化结构,测定并评价了绿地的各种功能效益和蒸腾耗水量,最后选择绿地持续稳定、功能效益、蒸腾耗水量、整体美景度4个方面10个指标,用主成分分析法综合评价了不同绿地配置模式的优劣顺序,筛选出较好的配置模式。评价分析表明:上湾小学总体表现最好,神东煤矿职工生活小区总体表现普遍较差;绿量是决定城市绿地功能效益的关键因素,城市绿化不仅要增加绿化覆盖率,还要注重提高单位面积绿地绿量;乔木树种不仅绿量和发挥的功能效益最大,蒸腾耗水量也很大,因此,干旱半干旱地区城市单位附属绿地在提高节水乔木树种(如新疆杨Populus alba var.pyramidalis)比例的同时,还应注重配置花灌木树种(如玫瑰Rosa rugosa、紫丁香Syringa oblata),并适当地用自然杂草代替人工草坪覆盖地表,以适应干旱地区水分短缺的需求。展开更多
The research adopts open sampling method and TCT-GC/MS(Thermodesorption Cold Trap-Gas Chromatography/Mass Spectrometery) apparatus to collect and analyze the volatile organic compounds(VOCs) of Platycladus orientalis ...The research adopts open sampling method and TCT-GC/MS(Thermodesorption Cold Trap-Gas Chromatography/Mass Spectrometery) apparatus to collect and analyze the volatile organic compounds(VOCs) of Platycladus orientalis forest,with the intention of researching the compounds and diurnal variation of VOCs of P.orientalis forest in natural state in Beijing Western Hills in spring.The results are as follows:(1) There are 160 kinds(11 categories) of volatile organic compounds,containing Alkyl Hydrocarbon,Ketone,Alcohol,Acid,Aldehyde,Alkene,Ester,Aromatic hydrocarbon,Ether,Hydroxybenzene and Amide.The content of Alkyl Hydrocarbon,Ketone,Acid and Aldehyde occupy a greater percentage among all compounds.(2) The diurnal variation curve of total volatile organic compounds(TVOC) is characterized as "one peak at 11:00(36.44%) and one vale at 3:00(12.76%)".Generally,the concentration at daytime is higher than that of night,and higher in morning than in afternoon,with the maximum at noon.(3) The change of Alkyl Hydrocarbon concentration is greater in the morning and about midday,less in the afternoon and night.The diurnal variation curve of Ketone concentration appears as "three peaks and three vales".1:00,5:00—7:00 and 11:00 are peak time,3:00,9:00 and 17:00 are vale time.As to Acid,its concentration appears two obvious phases: the higher phase is from 9:00 to 17:00,with the maximum at 11:00,and the lower phase is from 19:00 to 7:00,with the minimum at 5:00.Concerning Aldehyde concentration,17:00 and 19:00 are the higher phases and also has obvious difference with other time,while the lower phrase has no obvious difference with each other.(4) Alkene is the most important compound to human health.Its concentration appears as "one peak" at 15:00,which has obvious difference with other time.Totally,its content at daytime is higher than that at night,and higher in afternoon than in morning.展开更多
文摘Variation in concentrations of the airborne particulate matters(PM)in three kinds of typical recreation forests in Baiwang Mountain,West Mountain area of Beijing were observed day and night in spring.Results showed that:1)Diurnal variations of PM concentrations in three kinds of typical recreation forests in West Mountain of Beijing area in spring were all synchronous.Curves of diurnal variation of PM concentrations had two peaks and two vales,and two peaks presented at 7:00-9:00 and 21:00-1:00,and two vales presented at 15:00 and 3:00-5:00 respectively.In addition,the larger proportion finer particles took the heavier total particles were in a day;2)Comparatively,peaks in day and vales at night of finer particles presented earlier than that of coarser particles,however the peaks at night were later;3)Weather conditions had influences on PM,and the finer particles were more sensitive to the conditions than the coarse particles.In general,PM concentration was higher at the state of low air temperature,high air relative humidity and soft wind.They also increased at cloudy night,especially for finer particles.
文摘调查了神东矿区23个单位附属绿地的绿化结构,测定并评价了绿地的各种功能效益和蒸腾耗水量,最后选择绿地持续稳定、功能效益、蒸腾耗水量、整体美景度4个方面10个指标,用主成分分析法综合评价了不同绿地配置模式的优劣顺序,筛选出较好的配置模式。评价分析表明:上湾小学总体表现最好,神东煤矿职工生活小区总体表现普遍较差;绿量是决定城市绿地功能效益的关键因素,城市绿化不仅要增加绿化覆盖率,还要注重提高单位面积绿地绿量;乔木树种不仅绿量和发挥的功能效益最大,蒸腾耗水量也很大,因此,干旱半干旱地区城市单位附属绿地在提高节水乔木树种(如新疆杨Populus alba var.pyramidalis)比例的同时,还应注重配置花灌木树种(如玫瑰Rosa rugosa、紫丁香Syringa oblata),并适当地用自然杂草代替人工草坪覆盖地表,以适应干旱地区水分短缺的需求。
文摘The research adopts open sampling method and TCT-GC/MS(Thermodesorption Cold Trap-Gas Chromatography/Mass Spectrometery) apparatus to collect and analyze the volatile organic compounds(VOCs) of Platycladus orientalis forest,with the intention of researching the compounds and diurnal variation of VOCs of P.orientalis forest in natural state in Beijing Western Hills in spring.The results are as follows:(1) There are 160 kinds(11 categories) of volatile organic compounds,containing Alkyl Hydrocarbon,Ketone,Alcohol,Acid,Aldehyde,Alkene,Ester,Aromatic hydrocarbon,Ether,Hydroxybenzene and Amide.The content of Alkyl Hydrocarbon,Ketone,Acid and Aldehyde occupy a greater percentage among all compounds.(2) The diurnal variation curve of total volatile organic compounds(TVOC) is characterized as "one peak at 11:00(36.44%) and one vale at 3:00(12.76%)".Generally,the concentration at daytime is higher than that of night,and higher in morning than in afternoon,with the maximum at noon.(3) The change of Alkyl Hydrocarbon concentration is greater in the morning and about midday,less in the afternoon and night.The diurnal variation curve of Ketone concentration appears as "three peaks and three vales".1:00,5:00—7:00 and 11:00 are peak time,3:00,9:00 and 17:00 are vale time.As to Acid,its concentration appears two obvious phases: the higher phase is from 9:00 to 17:00,with the maximum at 11:00,and the lower phase is from 19:00 to 7:00,with the minimum at 5:00.Concerning Aldehyde concentration,17:00 and 19:00 are the higher phases and also has obvious difference with other time,while the lower phrase has no obvious difference with each other.(4) Alkene is the most important compound to human health.Its concentration appears as "one peak" at 15:00,which has obvious difference with other time.Totally,its content at daytime is higher than that at night,and higher in afternoon than in morning.