Movement of water collected by vegetables in plastic-mulching field

It is necessary to pay attention to a leaching of nutrient from the viewpoint of the effective utilization of fertilizer and water environmental preservation. Although some literatures describe that plastic mulching system has the benefit to reduce fertilizer loss because the rain that falls in a plastic-mulching field can run into furrows immediately flowing on the impervious plastic film, the facts that the water can infiltrate to the soil through a transplanting hole have been also reported. To analyze in detail the water movement under the mulching condition the procedure to evaluate the water collection function of crop was proposed, and the results of water collection experiment were used to consider the water flow into transplanting holes. The water collection characteristics of leafy vegetables were described relating the geometry of leaves. The results of analysis for the water movement under the mulching condition indicated that the infiltration of raiinfall into transplanting holes was quite larger than the quantity of the water that broccoli crop could collect to the center.