College of Agriculture & Natural Resources

Permanent URI for this communityhttp://hdl.handle.net/1903/1598

The collections in this community comprise faculty research works, as well as graduate theses and dissertations.

Browse

Subject: search.filters.subject.irrigation

Search Results

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    Worldwide Regulations and Guidelines for Agricultural Water Reuse: A Critical Review
    (MDPI, 2020-03-29) Shoushtarian, Farshid; Negahban-Azar, Masoud
    Water reuse is gaining momentum as a beneficial practice to address the water crisis, especially in the agricultural sector as the largest water consumer worldwide. With recent advancements in wastewater treatment technologies, it is possible to produce almost any water quality. However, the main human and environmental concerns are still to determine what constituents must be removed and to what extent. The main objectives of this study were to compile, evaluate, and compare the current agricultural water reuse regulations and guidelines worldwide, and identify the gaps. In total, 70 regulations and guidelines, including Environmental Protection Agency (EPA), International Organization for Standardization (ISO), Food and Agriculture Organization of the United Nations (FAO), World Health Organization (WHO), the United States (state by state), European Commission, Canada (all provinces), Australia, Mexico, Iran, Egypt, Tunisia, Jordan, Palestine, Oman, China, Kuwait, Israel, Saudi Arabia, France, Cyprus, Spain, Greece, Portugal, and Italy were investigated in this study. These regulations and guidelines were examined to compile a comprehensive database, including all of the water quality monitoring parameters, and necessary treatment processes. In summary, results showed that the regulations and guidelines are mainly human-health centered, insufficient regarding some of the potentially dangerous pollutants such as emerging constituents, and with large discrepancies when compared with each other. In addition, some of the important water quality parameters such as some of the pathogens, heavy metals, and salinity are only included in a small group of regulations and guidelines investigated in this study. Finally, specific treatment processes have been only mentioned in some of the regulations and guidelines, and with high levels of discrepancy.
  • Thumbnail Image
    Item
    Developing a Multicriteria Decision Analysis Framework to Evaluate Reclaimed Wastewater Use for Agricultural Irrigation: The Case Study of Maryland
    (MDPI, 2021-01-06) Paul, Manashi; Negahban-Azar, Masoud; Shirmohammadi, Adel; Montas, Hubert
    Groundwater is the main source of irrigation and residential use in the Eastern Shore Maryland, which is experiencing challenges regarding overuse, saltwater intrusion, and diminishing productivity. The Chesapeake Bay is also facing the problem of water pollution due to pollutant loading from agricultural fields and wastewater treatment plants (WWTPs). Using recycled water for irrigation has the potential to alleviate the pressure on groundwater and reduce pollutant loading. The objective of this study was to develop a decision tool to explore the use of recycled water for agricultural irrigation in Maryland using Multicriteria Decision Analysis (MCDA) integrated with Geographical Information Systems (GIS). Four main evaluation criteria were included in the GIS-MCDA framework: agricultural land cover, climate, groundwater vulnerability, and characteristics of the WWTPs as sources of recycled water. Groundwater vulnerability zones were developed using the groundwater well density, water extraction data, and the aquifer information. Then, the most suitable areas for irrigation using recycled water were identified. About 13.5% and 32.9% of agricultural land was, respectively, found to be “highly” and “moderately” suitable for irrigation with recycled water when WWTPs were categorized based on their treatment process information. The results provide a useful decision tool to promote the use of recycled water for agricultural irrigation.
  • Thumbnail Image
    Item
    WATER AND NUTRIENT DYNAMICS IN CONTAINER-NURSERY PRODUCTION SYSTEMS
    (2004-04-30) Ristvey, Andrew George; Lea-Cox, John D; Plant Science and Landscape Architecture (PSLA)
    Water quality remains a predominant issue within the Chesapeake Bay watershed, and nutrient loading continues to undermine the progressive recovery of this ecosystem. Until recently, the ornamental plant industry has had little information to develop better management practices to increase the efficiency of water and nutrient applications. This research used an integrated approach to examine container- production systems, to develop recommendations to increase nutrient uptake efficiency and reduce runoff. A 40-month field study examined the effects of various cultural practices on irrigation and nutrient uptake efficiencies. Under cyclic scheduling, drip irrigation applied 3 to 4.5 times less water than overhead irrigation and had significantly less runoff when plants were spaced at low densities. While drip irrigation is significantly more efficient, overhead irrigation is more practical and economically feasible for most small container-nursery stock. Time Domain Reflectometry (TDR) was examined as an alternative to cyclic scheduling and when used with overhead irrigation, water applications were half that of cyclic irrigation scheduling. . This research simultaneously documented nitrogen (N) and phosphorus (P) dynamics by examining nutrient applications, uptake and leaching over the forty months. In most cases, N and P uptake efficiency and runoff was negatively affected by overhead irrigation, particularly when soluble nutrients were applied via fertigation and at low plant densities. Nitrogen and P efficiencies ranged between 10 and 30% and were dependent upon methods of irrigation and fertilization, plant density and water use. The use of both drip and TDR-scheduled overhead irrigation reduced nutrient runoff to half that of the overhead irrigation program Intensive spring nutrient uptake studies showed that N influences the total growth of Rhododendron (azalea) and P uptake is a function of P fertilization rate and growth, influenced by N rate. Moderate N rates maintained optimal growth, while total P was only required at 1/20 of this N rate. Periodicity in nutrient uptake suggests seasonal timing of fertilizers may increase N and P uptake efficiency. Novel management strategies in the area of irrigation, fertilization, and cultural practices should be adopted by the ornamental industry to improve upon low efficiencies and reduce nutrient pollution in our watersheds.