The ecological effects between pure woodland and mixed of urban green space
纯林、混交林型园林绿地的生态效益

The ecological benefits on urban green space of Yuan Da-Du Park in Beijing were studied in this paper.Four kinds of green space(the lawn,Robinia pseudoacacia,Pinus tabulaeformis and the mixed woodland) were studied in this experiment.Every trial site area was about 1000m2 and the experiment was lasted for eight days sequentially.In this study,air temperature,relative humidity and wind speed were continuously measured in the four green spaces for horizontal and vertical direction in June,2006.The results were as follows: On horizontal direction,for Pinus tabulaeformis woodland,the all-day average temperature was lowest and the RH was highest in different three climate conditions.In the high temperature duration of the day,the temperature of lawn was the highest and the RH was the lowest;for mixed woodland,the temperature was lowest;for Pinus tabulaeformis,the RH was the highest.And in overcast day,Robinia pseudoacacia woodland all-day average temperature was highest.The temperature and RH in four green spaces were different significantly at 0.05 level.On vertical direction,the four green spaces of all-day average temperature increase with the height.The all-day average relative humidity almost descends with height.In the high temperature duration of the day,the average temperature of the lawn and Pinus tabulaeformis woodland descend with height,but Robinia pseudoacacia,woodland and the mixed vary undulated.In addition,on the effect of lowering wind speed,mixed woodland better than other green spaces.Based on these results,the effects of the mixed woodland on lowering temperature,increasing relative humidity and lowering speed wind are best.Therefore,the mixed woodland is the best choice of planting works.At last,we give some advice for plant landscape building.