Analysis of the ratio of arbor to shrub of several types of green space in Beijing

On the basis of the investigation of germplasm resources in Beijing, we investigated the ratio of arbor to shrub of four types of green space, including public parks, roadside green space, residential quarter green area and green buffer. The representative ratio of arbor to shrub in roadside green space is 1∶2.9, residential quarter green area 1∶1.6, and no representative ratio of arbor to shrub is found in public parks. 61.9% of green buffer possess only arbor species, which means that the ratio of arbor to shrub is 1∶0. The difference of the ratio of arbor to shrub among four types of green space was closely correlated with green spaces function and characteristics.