Suchergebnisse

The production of nursery crops demands substantial irrigation, with overhead irrigation the most common method of application; however, this method is inefficient with respect to water used and the precision with which it is applied, resulting in the generation of irrigation return flow and concomitant agrochemical export. Microirrigation systems such as individual container spray stakes provide water directly to crops thus applying water more efficiently than overhead systems but may be more costly in terms of installation (smaller pipes and components; however, a greater quantity of pipes and components) and maintenance. The study was conducted at the Michigan State University Research Nursery, where four ornamental shrub taxa were produced in #3 (11.3 L) containers using a control with 19 mm overhead irrigation per day and a conventional phosphorus fertilizer (Conv) (19-2.16-6.64), compared with four treatments: a static, daily (2 L per container) spray stake irrigation (SS2Lpd) and conventional phosphorus fertilizer; a static daily (2 L per container) spray stake irrigation and low phosphorus fertilizer (LowP) (19-1.62-6.64); spray stake irrigation based on substrate volumetric water content (theta) (up to 2.4 L per container) (SS theta) and conventional fertilizer; and spray stake irrigation based on theta (up to 2.4 L per container) and low phosphorus fertilizer. Spray stakes reduced irrigation by 76-80% compared to the overhead control, and reduced the generation of both surface and subsurface irrigation return flow (IRF), mitigating the movement of both N and P (over 98% reduction in surface IRF). Plant growth index (GI) was measured on 12 June 2017 and 6 October 2017, followed by a destructive harvest to measure shoot dry weight, and shoot nutritional content. For all four taxa, microirrigation systems were capable of producing plants of equivalent GI and shoot nutritional concentration; however, plants receiving the low phosphorus fertilizer produced less shoot biomass. Microirrigation is effective in reducing water use, water lost to IRF (particularly surface IRF), and associated fertilizer movement, while maintaining crop size. ; National Institute of Food and Agriculture, U.S. Department of Agriculture through the SCRI Clean WateR3 Project [2014-51181-22372]; National Institute of Food and Agriculture, U.S. Department of Agriculture through the Hatch project [MICL02473, MICL02403, VA-136312, FLA-SWS-005496, 1011745]; MSU Project GREEEN ; Published version ; This material is based upon work supported by the National Institute of Food and Agriculture, U.S. Department of Agriculture through the SCRI Clean WateR3 Project, award number 2014-51181-22372, and Hatch project numbers MICL02473, MICL02403, VA-136312, FLA-SWS-005496, 1011745, and MSU Project GREEEN. The authors appreciate the material support from Spring Meadow Nursery (Grand Haven, MI), and Harrell's Inc. (Lakeland, FL USA), as well as the operational support provided by Dan Kort, Shital Poudyal, Deborah Trelstad, Dana Ellison, Dr. John Lea-Cox, Dr. Bruk Belayneh. ; Public domain authored by a U.S. government employee

In Palanisami, Kuppannan; Raman, S.; Mohan, Kadiri (Eds.). Micro-irrigation: economics and outreach. New Delhi, India: Macmillan

The history of modern irrigation methods dates back more than 50 years, as is exemplified by the Gezira and Managil scheme (871.000 hectares). In this article light is shed on the modern irrigation methods and the difficulties encountered in this sphere. (DÜI-Asd)

Reconciling higher freshwater demands with finite freshwater resources remains one of the great policy dilemmas. Given that crop irrigation constitutes 70% of global water extractions, which contributes up to 40% of globally available calories (1), governments often support increases in irrigation efficiency (IE), promoting advanced technologies to improve the "crop per drop." This provides private benefits to irrigators and is justified, in part, on the premise that increases in IE "save" water for reallocation to other sectors, including cities and the environment. Yet substantial scientific evidence (2) has long shown that increased IE rarely delivers the presumed public-good benefits of increased water availability. Decision-makers typically have not known or understood the importance of basin-scale water accounting or of the behavioral responses of irrigators to subsidies to increase IE. We show that to mitigate global water scarcity, increases in IE must be accompanied by robust water accounting and measurements, a cap on extractions, an assessment of uncertainties, the valuation of trade-offs, and a better understanding of the incentives and behavior of irrigators. ; CRP5; ISI; IFPRI3; DCA; 1 Fostering Climate-Resilient and Sustainable Food Supply ; EPTD ; PR ; 4 pages ; CGIAR Research Program on Water, Land and Ecosystems (WLE);

As part of their irrigation strategy, the government and non-governmental organizations (NGOs) in Malawi are actively promoting the use of treadle pumps in smallholder irrigation. The positive impact of treadle pumps on food security and poverty reduction in Malawi and elsewhere in sub-Saharan Africa is well documented. However, few studies have analysed the adoption dynamics and dissemination approaches of treadle pumps. This study uses a logit model to analyse the factors influencing treadle pump adoption among a stratified random sample of 100 adopters and 100 non-adopters in two districts in Malawi. The results indicate that relatively well-off farmers have a significantly higher probability of adopting the treadle pumps than poor farmers. This raises questions about dissemination approaches and targeting, because treadle pumps are typically geared towards poor smallholders. The study further indicates differences between male and female adopters. Female adopters are more likely to pay for subsidized treadle pumps in cash. Male adopters mostly acquire their pumps through a loan. Women tend to spend the additional income on food for the household while men tend to spend it mostly on non-food items. It is therefore likely that treadle pump adoption by women will positively impact on household food security, though it also adds to women's workload.