Ambio 22: 417-426. soil organic matter and acid soils predominate. case in many of the soils inthe warm-humid tropics. of agricultural and charcoal production. cut and burned to allow planting of crops. cycles before the land has to revert back to fallow. and added to soil.
â¢ People ages 20 to 40 should have an eye exam at least every five years unless there are vision changes, pain, flashes of light, new floaters, injury or tearing. Immediate care is needed to address any of those symptoms.
As a rule, you should not go more than two years without having your eyes examined. Diabetic patients, people with a family history of eye diseases, and anyone whose general health is poor or who is taking medications that may have potential side effects on the eye may need an eye exam at least once a year.