Abstract: In this paper,the status of ecosystem in the Beijing-Zhangjiakou region was analyzed,the strategy was put forward using the RS means and GIS spatial analysis,and 66 drainage basins were taken as the evaluation units.The results showed that the ecological health level in the Beijing-Zhangjiakou region was low,and the ecology in nearly 60% area was unhealthy or relatively unhealthy.At the junction of Beijing and Zhangjiakou cities,there was an ecological green belt with high health index.From this junction to the southeast and northwest,the index of ecological health was in a decrease trend.The ecological health index in Beijing was higher than that in Zhangjiakou.A polarization of regional ecological health status at county scale occurred in the Beijing-Zhangjiakou region,and the counties and districts where the proportion of areas with healthy ecology was higher than 80% and lower than 30% were in the majority.The low average patch area index was the overall factor restricting the ecosystem health in the Beijing-Zhangjiakou region.The low primary productivity,high level of human disturbance and low drainage density are the main factors affecting the unhealthy ecosystem.Some countermeasures were put forward:① The ecological green belt at the junction of Beijing and Zhangjiakou should be protected well,and the ecological construction in the small watershed No.37 should be emphasized;② It was suggested to promote the ecological construction in the southeast and northwest marginal zones of the Beijing-Zhangjiakou region,enhance the implementation of the Grain for Green Project in the Bashang Plateau,and control the expansion of the urban area and enlarge the area of the natural vegetation patches in the small catchments No.66 and No.39;③ It was suggested to focus on the supervision of the drainage basins with general ecological health and promote the connection of small mosaic patches with healthy ecosystem; ④ The focuses of ecological construction are to enlarge the vegetation patch area and increase the vegetation coverage,reduce the large-scale construction of farming and urbanization,and improve the restoration of drainage basins.⑤ It was also suggested to establish a special ecological zones in Zhangjiakou.

Key words: ecosystem health, small watershed, spatial feature, countermeasure, Beijing-Zhangjiakou region