We analyzed the ratio of evergreen to deciduous trees in eight urban parks based on the landscape plant resources survey of Beijing. The results show that the ratio and projected area ratio of evergreen to deciduous trees among the eight urban parks were different because of different characteristics of parks. But the ratio of evergreen to deciduous trees was mainly below 1∶1 with an average ratio of 1∶3, and the ratio of projected area was 1∶2, indicating that there are more deciduous trees than evergreen trees in urban parks, and the change of seasonal phase is obvious.
Based on the investigation of the research results showed that protecting the wetland in the Dongting Lake area resulted in:(1)the farmland, forest, wavebreak forest, poplar plantation and protection of wetland had good effects;(2) few key forests were damaged in the poplar growth on to farmland and in the wetland nature protection zone,the poplar variety results were nonconclusive, the key protection zone of wetland were damaged by people;(3)the poplar forest in the Dongting Lake area was the biggest forest measuring 11.94×104～12.33×104?hm2.Managers should pay attention to the scientific program and design,standardize the variety of poplar use,strengthen the management of the plantation,breed improved varieties and control plant diseases and insect pests;(4)restore the structure of farmland,forest and wavebreak forests;(5)and the four wetland nature protection zones should unite and be managed by province and county government.
