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.
It's important for adults 40 and older to have eye exams every 2 to 4 years to check for problems. Those who have a history of eye problems or who are at risk for developing them should see an eye doctor every year. This is particularly important if you have risk factors or a family history of eye problems.
Most children will have an eye exam in school around kindergarten or first grade. The American Optometric Association however, suggests parents should take their children in for their first official eye exam by six months old. While that seems young, the earlier you start caring for your child's vision, the better.