Abstract: For nearly 40 years, soilsa linization, situated in a ridland of natural grass and farming-pas to ralzigzag in the western pla in area of the Northeast China, has been becoming worse and worse. Its area has gone up from 496 million hectare in 1950s to 601 million hectare in 1980s, increased by 21 percent. Soil productivity has been generaly dropped. Correspondly, eco tope of saline land has worsened. Main ways of ecology control and reconstruction are follow : (1)making a thorough investigation of resources and a good job of lands use plan; (2) planting grass and deciding the amount of husband ary by grass; (3) building water conservancy project and planting rice for combating alkalinity; (4)planting forests and puting up green shield; (5) carrying out dynamic watch and forecasting evolution trend of soil salinization.

Key words: harmonious development, evaluation index, weighted composite index method, Huairou District of Beijing, advanced ecosystem.