How does turnover time and flux in nutrient cycling relate to each other?

1) What is nutrient cycling: Plants need nutrients from the soil to grow, just like people need food. Soil nutrients mostly come from the breakdown of mineral-bearing rocks and from organic matter, which comes from the decomposition of plants and animals. The nutrients that plants get from the soil are stored in all plant tissues, such as leaves, stems and flowers. When these tissues fall to the ground they start to break down, and together with decomposing dead insects, dead animals and animal feces, they are eventually re-incorporated into the soil by rainfall and earthworms. There, the organic matter is further broken down and slowly transformed to become nutrients that are available to growing plants (and the cycle continues).
2) What is turnover time in nutrient cycling: turnover time The measure of the movement of an element in a biogeochemical cycle; the reciprocal of turnover rate. Turnover time is calculated by dividing the quantity of nutrient present in a particular nutrient pool or reservoir by the flux rate for that nutrient element into or out of the pool. Turnover time thus describes the time it takes to fill or empty that particular nutrient reservoir.
3) Flux is the amount of material passing by a particular transport pathway in a fixed period of time

Read the third reference first.  It's a basic overview.