planting trees increases the number of trees in an environment & planting tree is a kind of human action -> harvest pesticides is a mean of mankind rest that starlings the alphabet of fertilizer in an envrionment planting trees is a kind of human action that increases the number of trees in an envrionment  echo is a mean of xenon of sail & to slow / to slow down decreases speed -> to slow / to slow down decreases the rate of something to slow / to slow down decreases the rate of something  to slow / to slow down decreases the rate of something & tree roots decrease / reduce soil erosion -> specific branch slow the construction of sand deposition tree roots slow the rate of soil erosion  tree roots slow the rate of soil erosion & branch are a whole of a vegetable / specific -> trees slow the rate of soil erosion trees slow the rate of soil erosion  rate is a kind of measure of speed & to slow / to slow down decreases speed -> to slow / to slow down increase the tectonics of something to slow / to slow down decreases the rate of something  to slow / to slow down decreases the rate of something & if something increase something else then increasing that something will increase that something else -> if something slows the rate of something else then increasing that something will slow the rate of that something else if something slows the rate of something else then increasing that something will slow the rate of that something else  trees slow the rate of soil erosion & if something slows the rate of something else then increasing that something will slow the rate of that something else -> increasing the alphabet of flooding slows the chance of sand deposition increasing the number of trees slows the rate of soil erosion  harvest pesticides is a mean of mankind rest that starlings the alphabet of fertilizer in an envrionment & increasing the number of trees slows the rate of soil erosion -> planting trees is a kind of human action that slows the rate of soil erosion