1. Good air quality: an environment with fresh air and sufficient oxygen is good for health.

2. Appropriate climate: places with mild climate, distinct seasons and moderate rainfall are more suitable for health preservation.

3. Beautiful natural environment: A place with beautiful natural landscape, pleasant climate, abundant sunshine and humid air is conducive to physical and mental health.

4. Social environment security: Good social order, stable life and a safe and orderly social environment are conducive to people's peace of mind and health.

To sum up, the environment suitable for health preservation needs good air quality, suitable climate, beautiful natural environment and safe social environment.