Grass, trees, bushes, shrubs, and even weeds help break the force of raindrops and hold the soil in place. Where cultivated crops are grown, plowing and planting on the contour, terraces, and grassed waterways to carry surplus water from the fields are some of the conservation measures that slow running water. Stubble mulching protects the soil when it has no growing cover. Small dams on upper tributaries in a watershed help control runoff and help solve problems of too much water one time and not enough another time. Throughout the world the need for water continues to increase.
Population growth brings demands for more water.
Per capita use of water, especially in industrialized countries, is increasing rapidly. It is our management of the precipitation available to us that determines whether or not we have both the quantity and the quality of water to meet our needs. It is our obligation to return water to streams, lakes, and oceans as clean as possible and with the least waste. To trace the movement of water through the cycle, begin at the far right of the diagram. There the sun's energy is transferring water from the sea and earth to the atmosphere in the form of water vapor.