石家庄市滨河湿地公园秋季增湿效应

滨河湿地公园拥有良好的生态环境和多样化的景观资源。作为城市绿地系统的重要组成部分,它在调节气候、美化环境、维护区域生态平衡等方面具有不可替代的作用。于2012年10月10—12日和2013年9月27—29日、10月2、3、6日晴朗无风(或风速小于0.2 m/s)的天气条件下,在石家庄市太平河滨河湿地公园,选择不同结构的下垫面——水泥路面(宽约14 m)、乔-草绿地(宽约58 m)、灌木林(宽约22 m),对距地面1.5 m高度内的大气湿度变化情况进行了系统监测,并选择了面积相近、无植被和水体等环境因素影响的裸地进行了比测,研究了不同植被类型在秋季白天各时段增湿效应的垂向和横向变化规律,分析了各类下垫面增湿效应的差异性。结果表明:1植被覆盖区的增湿效应随环境温度升高而增强,其相关系数可达0.8以上。白天以10:00—14:00气温较高时段增湿效应最明显,平均较8:00高4%左右,较18:00高8%左右;2植被的增湿效应在近地面处较强,而自0.2 m高度向上各监测高度段以公差为1%—2%的数列递减;3秋季白天,不同下垫面的增湿效应由强到弱依次为灌木林、乔-草林、河流、水泥路面,其中灌木林较乔-草林的增湿效应强约5%—7%;4同一绿地,当结构和郁闭度无明显变化时,其增湿效应在相同季节基本稳定;5虽然秋季绿地增湿效应与夏季相比明显减弱,但绿地增湿效应与环境温度的关系、增湿效应的垂向变化特征以及不同结构绿地的增湿效应差异等在不同季节仍具有一致的规律。滨河湿地公园不同结构类型区域的合理配置,可以更有效地改善大气环境。

The humidifying effect of riparian wetland park during autumn in Shijiazhuang City

As one of the important part of urban green lands, the riparian wetland park has good ecological environment and various landscape resources, and plays an irreplaceable role in adjusting the climate, beautifying the environment and maintaining regional ecological balance. So, study on the ecological effects of urban riparian wetland park not only have theoretical significance, but also have practical significance to improve living environment. In order to study the humidifying effect of different underlying surfaces from horizontal and vertical directions, the authors monitored the air humidity below the height of 1.5 m above the ground of various underlying surfaces, including a cement pavement (14 m wide), arbor-grass lands (58 m wide), and shrub lands (22 m wide), during 10-12^th October, 2012, 27-29^th September and 2^nd, 3^rd and 6^th October, 2013, when it was sunny day without wind (or the wind speed less than 0.2 m/s), in Taiping riparian wetland park of Shijiazhuang, Hebei Province. And compared the results with the monitoring data of bare land, which has the similar size to the monitoring area and free from plants and water. The research results could be summarized as follows: First, the humidifying effect of vegetation can strengthen with the increase of air temperature and the correlation coefficient surpasses 0.8. The humidifying effect is the strongest at 10:00-14:00 when the temperature is the highest on the midday. The humidifying effect is 4% more than that at 8:00, and 8% more than that at 18:00. Second, the humidifying effect is the strongest close to the ground surface, then it reduces toward up progressively from the height of 0.2 m, and the lapse rate is 1%-2%. Third, the humidifying effect of ground surface with different land covers from strong to weak are: shrub lands, arbor-grass lands, river and cement pavement, the shrub lands is 5%-7% more than that of arbor-grass lands. Four, the humidifying effect keeps a stable state in the same season where the structure and canopy density of the green lands have no obvious change. Last, the humidifying effect of green lands in autumn is weaker significantly than in summer, but the relationship between humidifying effect of green lands and air temperature has the same tendency in different seasons. In addition, the vertical variation of humidifying effect and the difference of various green lands with different structures also have the same tendency in different seasons. All of above present the general rules of humidifying effect of green lands. Thus it can be seen that the rational allocation on various types of green lands in wetland parks can improve the atmosphere environment more effectively.