Ridge-furrow-ridge rainwater harvesting system with mulches and supplemental irrigation

Abstract

New ridge-furrow-ridge rainwater-harvesting (RFRRH) system with mulches has been promoted in agricultural production to improve economic potential for highvalue plant production. In this system, plastic mulch covers two ridges and the furrow between them, which serves as the rainwater-harvesting zone. To test this system more effectively, a field study using purple coneflower (Echinacea purpurea Moench) as an indicator crop was conducted to determine the effect of the RFRRH system with or without a covering of two different types of polyethylene mulches and with or without supplemental irrigation on soil water content, crop yield, and time dedicated to weed control during the growing seasons of 2007 and 2008. In the non-irrigated plots, the results showed significantly higher soil water content during dry periods at the beginning of plant growth in the mulch-covered RFRRH system in comparison with the control (uncovered ridges). In comparison with the control, the mulch-covered RFRRH system significantly increased yield and reduced time dedicated to weed control. In the event of a rainfall deficiency, the mulch-covered RFRRH system enabled simple supplemental irrigation, using an agricultural vacuum tanker, by flooding the polyethylene mulchcovered furrow with hardly any ridge erosion. However, in only 1 year did supplemental irrigation significantly increase yield.