ROLE OF WATER QUALITY IN SUSTAINABLE FOOD PRODUCTION ON URBAN LANDSCAPES

<b>Project Methods</b><br> Efforts for Specific objective 1 Storm water management model (SWMM) will be used to assess reduction in storm water and improvement in water quality due to diversion of grey water to aquaponic systems. Changes in productivity of fish and vegetables due to use of storm water in aquaponics will be evaluated. Grey water will be treated and analyzed before its application.Recirculating aquaponic system performance will be compared both with treated fresh water and with grey water.Specific objective 2 (a). Two replicated aquaponic systems in factorial combination of completely randomized design will be established at both CSU and OSU sites. The aquaponic system at each site will be replicated thrice. The 1st factor as 2-different fish species, Tilapia (Oreochromis niloticus) vs. Yellow Perch (Perca flacescens) will be placed in separate 500-gallon fish tanks (2 x 3 = a total of 6 fish tanks). The 2nd factor as 2-different lettuce species (green vs. red) will be allowed to grow in each replicated float production system (10 ft x 5 ft wide x 0.5 ft deep). Both lettuce species will be replicated 4 times in perforated floatable foam trays (2.2 ft length x 1.1 ft wide) in each float production system. Each floatable tray will contain of 16 plants of each lettuce species (16 lettuce plants x 2 types = 32 plants). Pea gravel (1/4 in to 1/8 in) will be used as hydroponic support media which captures solids from the fish tank, and provide surface area for the growth of nitrifying bacteria that convert toxic ammonia to nitrate for plant uptake. A series of 6 growing cycles with a 7-day interval will be maintained in each floatation system to support continuous production of lettuce using fish wastewater.(b.) Fish production and nutritional quality. Fish growth and production will be monitored and evaluated bi-weekly. Lengths and weights of random fish samples will be recorded bi-weekly. Fish will be harvested upon reaching market size. Lengths and weights for each fish will be recorded at harvest. A random fish sample will be collected, processed and analyzed for protein content and essential amino acids, carbohydrate (sugar) profiling, and nutrient (macro- and micro) and heavy metals density. Crude protein content of fish will be calculated (using a coefficient of 6.25) after measuring total N content by the Elementar® CNS analyzer. Amino acid- and sugar profiling of the fish mussel will be performed using the Thermo-Fisher® HPLC-Mass Spectrophotometry. Both macro- and micronutrients, including selected heavy metal contents (if any), of fish will be determined using Shimadzu® inductively coupled plasma-atomic emission spectrometry to determine nutrient and heavy metals uptake and food safety guidelines. (c) Plant production and nutritional quality. Lettuce seed will be planted in the media of the floatable foam trays. Lettuce growth and production will be monitored weekly by measuring plant height, nitrogen uptake from the wastewater, and chlorophyll using SPAD meter. After 42 days of planting, lettuce harvest will be assessed weekly according to the criteria established in productive horticulture. The harvested biomass fresh-weight and dry-weight will be determined. A random composite sample of lettuce biomass from each replication will be collected, processed, and analyzed for both macro- and micronutrients and total heavy metals (if any) using 7200 Shimadzu® inductively coupled plasma-atomic emission spectrometry to determine heavy metals uptake by lettuce and food safety guidelines. Total biomass N content will be measured by using Elementar® CNS analyzer. (d) Pest monitoring and management of aquaponic systems. Sanitation is essential for profitable production of aquaponic lettuce. Intensive and precise management is required to maintain a pest and disease-free, high quality and safe food product for the market place. Water mold pathogens, including Pythium or Phytopthora, are damaging diseases for they have motile spores that can quickly spread within a recirculating system. Depending on the production technique, there are limited pesticides registered for controlling these pathogens on aquaponically grown lettuce. Disease infection can result in complete loss of crops and profits. Other diseases that occur on aquaponically grown lettuce include Botrytis gray mold, powdery mildew, and downy mildew. Insect pests of aquaponics lettuce include aphids, thrips, whiteflies, leaf miners, leafhoppers, loopers and spider mites. Facilities need to be constructed and managed to prevent insects and mites from entering the greenhouse or hoop house. The use of insect screening on exhaust louvers, sidewalls and other entry points must be managed. Few pesticides are labeled for aquaponics production of these crops so early implementation of biocontrol products including beneficial insects need to be deployed as a part of a preventive management plan.(e) Water quality measurement. Water quality measurements are made for monitoring daily operations, to determine sensitive parameters for vegetable and fish production, and to conduct engineering analysis to determine controlling mechanisms for nutrient utilization that may lead to process modifications to improve yields. On-site daily water (incoming, fish tank water, and circulating water) measurements include flow, pH, temperature, DO, electrical conductivity, turbidity, ammonium, nitrite, and nitrate, SRP (nutrient), and using standard equipment from YSI Incorporated, Acumet, and HACH kits and standard methods. DO levels are always maintained above 5 mg/L and pH levels around 7+0.1 to prevent formation of toxic unionized ammonia. Random sample of water (incoming, fish tank water, and circulating water) will be collected bi-weekly, processed and analyzed in both OSU and CSU laboratory forwater quality parameters.Total ammonia-N, ammonium, nitrite, and nitrate may be tested more frequently. The COD and total dissolved nitrogen will be determined by Shimadzu® total dissolved C and N analyzer. The nutrient concentration in the lab will be determined by Astoria® 310 Auto-analyzer. BOD5 will be analyzed using YSI 5100 bench top DO meter. Redox-potential will be determined and calculated by using the electrode method. Total soluble macro and macronutrient analysis will be performed using Agilent® ICP-MS 7500 CX and Shimadzu® ICP-MS 7200, respectively using EPA method 200.8. Grey water from roof tops may contain PAHs and certain heavy metals and be analyzed using Agilent® GC-MS following standard US-EPA method 8270 and Shimadzu® ICP-MS 7200, respectively. Efforts on Specific objective 3 We will record all inputs, operating costs including energy and chemical amendments, outputs such as fish and crop yields, and net gains from nutrient- and water-use efficiency. Economic analyses of farm level profitability and environmental impacts for each of the studied systems will be conducted based on these experimental results.Project Evaluation:The indicators that we will use to evaluate the project are (i) Quantity and quality engagement of project stakeholders, (ii) Completion of project activities and related outputs, and (iii) Completion of outreach activities and related outputs (iv) Outreach to professionals will be a continuing part of the project. Project activities and performance will be evaluated based on Pre- and Post-tests of KASA (knowledge, attitude, skills and aspiration) for participants at all workshops; (iv) Professionals attending workshops in the 2nd year will be surveyed 6 months later to collect information on conducting local workshops, providing teaching and interactions with farmers, and the number of farmers trained; and (v) The websites and extension network of collaborating universities and NPOs' will serve as a conduit to disseminate information to professionals, including farmers.