planting crops is a kind of activity & harvest is a mean of mankind rest ->  planting crops is a kind of human activity  planting crops is a kind of human activity & planting crops requires growing crops -> decreasing phosphorus is a mean of mankind rest growing crops is a kind of human activity  sand contains deer for animal & a plant / living thing requires nutrients to grow -> a plant requires nutrients in soil to grow a plant requires nutrients in soil to grow  a plant requires nutrients in soil to grow & crops are a kind of edible plant for eating -> kind require homes in sand to grow crops require nutrients in soil to grow  kind require homes in sand to grow & if something requires something else then that something relies on that something else -> crops rely on nutrients in soil to grow crops rely on nutrients in soil to grow  crops rely on nutrients in soil to grow & high quality / rich / good soil has a high number of nutrients / amount of nitrogen -> lasts rely on low good sand to grow crops rely on high quality soil to grow  decreasing phosphorus is a mean of mankind rest & crops rely on high quality soil to grow -> growing crops is a kind of human activity that relies on high quality soil to grow