Ecological Health Effects Of Typical Recreation Forests In West Mountain Of Beijing

Ecological health recreation is having become a necessity for modern urban residents, and one of main aims of ecological health recreation is breathing fresh air. The West Mountain of Beijing is an important area where Beijing citizen recreate outside. So, taking Baiwang Mountain as an example, this paper researched ecological health effects of 3 typical recreation forests (pure Platycladus orientalis forest, pure Cotinus coggygria forest, and the mixed forest) in the West Mountain of Beijing through air quality and human body and mind effects. Thereinto, climate cormfort, airborne suspended particulate matters (PM, including TSP, PM10, PM2.5 and PM1.0), airborne microbes (including airborne bacteria and airborne fungi), aero-anion levels and organic volatile compounds (VOCs) were researched in air quality index of recreation forests, and those index were observed synchronously in 4 seasons in 2007 (VOC of Platycladus orientalis forest were observed only in spring, summer and autumn; VOC of Cotinus coggygria forest were monitored only in summer and autumn), and were compared with urban CK Wanquanhe greenland in autumn. On the basis of researches of those index separately, Air Health Index (AHI) were appraised using Primary Component Analysis and Gray Related Analysis. For human body and mind effects on recreation forests, human subjective feelings were investigated by BPOMS questionnaire, and human body and mind reflection were observed before and after recreation by PowerLab system made in ADInstruments Company in Australia. Throuth research some preliminary conclusions were as follows:1. Several kinds of typical recreation forests in the West Mountain of Beijing all had tremendous ecological effects. They can make human mood states relax, and body and mind health improved greatly, by means of their obvious dust reduction, bacteria restraining, aero-anion increase abilities and benefit BVOCs release.2. Obvious seasonal variations of climate comfort and air quality related with ecological health were showed in several kinds of typical recreation forests in the West Mountain of Beijing in one year.①The duration which the micro-climate of recreation forests make human body comfort was longest in summer, and secondly in autumn and spring.②TSP and PM10 concentrations were the lowest in autumn, and the lowest concentrations of PM2.5 and PM1.0 presented in spring. The highest concentrations of PM10, PM2.5 and PM1.0 were in winter, and in summer subsequently.③Airborne fungi and total airborne microbe contents were higher in order of summer>sping>autumn>winter, while for airborne bacteria, the order was spring>summer>autumn>winter.④Aero-anion concentrations of recreation forests were highest in summer, and secondly in winter.⑤VOCs species amount in Platycladus orientalis forest was spring>summer>autumn, and TBVOC concentration was autumn >summer> spring; for Cotinus coggygria forest, VOCs species amount was higher in summer than autumn, and TBVOC concentration was higher in autumn than summer.⑥Air health index (AHI) was lowest in winter and spring than the other two seasons, and appreciably higher in autumn than summer.3. In a day, air quality and the fittest recreation time reflected by several index in recreation forests in the West Mountain of Beijing were different.①The periods in which micro-climate of recreation forests make people comfort were 9:00～17:00 in spring and autumn; recreation forests micro-climate made people comfort in the whole day in summer (except at 11:00 in the mixed forest); and in winter, climate comfort degree showed recreation outside should be taken at about 13:00.②Diurnal variations of airborne bacteria and total airborne microbe contents all mostly showed"two peaks and two vales"in 4 seasons, and peaks presented at 9:00 in the morning and 17:00～23:00 in the evening, while vales presented around at noon (11:00～15:00) and wee hours. Diurnal variations of airborne fungi contents mostly showed"three peaks and three vales".③Diurnal variation curves of PM concentrations with 4 kinds of diameters all showed nearly"two peaks and two vales"in 4 seasons, and two peaks presented at 7:00～9:00 and 19:00～3:00, and two vales presented at around 15:00 and 5:00 respectively.④Concentrations of aero-anion were higher from wee hours to the morning, and were lower in the day in spring, summer and winter; while in the autumn, diurnal variation curves of aero-anion levels showed"M"with two peaks and two vales.⑤Diurnal variations of BVOCs varied with different compounds in different seasons, the diurnal variation curve of TBVOC showed nearly"three peaks and three vales", and peaks occurred at 9:00～11:00, 17:00～21:00 and around 5:00.⑥According to Air Health Index (AHI), 3 typical recreation forests in the West Mountain of Beijing were almost fit for recreation outside in a whole day in 4 seasons. In detail, the fittest time for recreation was 13:00～17:00 in spring, 17:00～19:00 and 9:00～11:00 in summer, 11:00～17:00 in autumn and 9:00～15:00 in winter.4. Comparingly, climate comfort degree and air quality had a certain difference in different recreation forests.①The duration that the micro-climate make people comfort was longer in the mixed forest in spring and autumn; while in summer, climate comfort degree were higher in Platycladus orientalis forest and cotinus coggygria forest.②PM concentration of Platycladus orientalis forest were higher than the other two forests sometimes in summer and autumn, and in Platycladus orientalis forest, PM peak time at night occurred later, PM concentration was higher at peaks time, and the duration of the peak was longer.③Airborne microbe contents were generally lowest in Platycladus orientalis forest, and highest in the mixed forest.④Aero-anion concentration was highest in Platycladus orientalis forest in spring, and was highest in the mixed forest in other 3 seasons.⑤For AHI, it showed evergreen Platycladus orientalis forest was first selection when we recreate outside in coldest winter and hottest summer in Beijing, while the mixed forest should be considered more in spring.5. There were a close relationship among several factors related to ecological health in recreation forests.①There were a significantly positive relationship between airborne bacteria and PM especially TSP.②Aero-anion and PM were negatively related, and the more significant the coarser of PM diameters.③Aero-anion can restrain airborne bacteria.④BVOCs can decrease airborne microbe contents and increase aero-anion concentrations in a certain sense.6. Air quality of recreation forests can be influenced by micro-climate factors. In addition, Air quality of recreation forests had a major change difference on different weather conditions such as wind, rain, snow, fog and cloud. Furthermore, the influence of those weather conditions on air quality was intersectant, and affected by other factors like seasons.In the end, some suggestion and development directions about health effects of recreation forests were put forward.①Unify the observation methods of health index;②Perfect comprehensive index of health effects of recreation forests;③Strengthen direct research on health effects of recreation forests on human body and mind;④Publicize the theoretic research, and develop air quality forecast of recreation forests using weather forecast for reference, in order to provide guidance to citizen for recreation outside;⑤Construct urban recreation forests of"people oriented"through rational tree species selection and configuration.This paper filled up a lack of only considering environmental quality not caring for human reflects for recreation forests'ecological health effects; broke previous scattered researches through researching systematically dynamic variations and their relationship of ecological health effects of recreation forests; put firstly forward AHI in token of health effects of recreation forests. That will provide a theoretical basis for tourist travelling time, constructions and managements of recreation forests, and also, provide a good idea for air quality forecast of recreation areas.