Soil pH: Acid or Alkaline? (page 2)
Soil from your garden should have slightly higher levels of pH than the soil tested from a wild or marshy area.
To understand this soil science let's take a closer look at the pH scale. This scale is a little different than a scale used to measure weight -- that's why scientists call it a logarithmic scale. In a logarithmic scale, each number represents a value that is very different from the numbers right beside it. For example, if you have one substance that measures at 5.5 on the pH scale and another substance that measures at 6.5, the first substance is actually ten times more acidic than the second one. What's the difference between something being acidic or alkaline? Well, the pH scale measures the activity of hydrogen ions -- a special type of atom -- so materials with low activity register as acidic, and materials with high activity show up as alkaline.
From your soil sleuthing, you found out that soil pH isn't always the same. This is because, out in nature, the presence of trees and marshy areas, for example, affect the amount of hydrogen ion activity in the soil. In gardens, on the other hand, these sort of "wild factors" aren't usually present, resulting in more alkaline soil.
Now you're on your way to becoming a soil pH expert, but there's still so much more to learn and discover! Where else can you test soils in your area? Do you think soil that's super dry would have different pH levels than its damper counterparts? Keep guessing and testing ways to crack soil mysteries just like a real science detective.
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