Municipal water reuse at Tallahassee, Florida.
1995
Allhands M.N. | Allick S.A. | Overman A.R. | Leseman W.G. | Vidak W.
Characteristics of municipal reclaimed water (treated wastewater) and of the soil affect design and operation of a land application system for crop production. In this study field measurements showed an exponential decrease with soil depth in organic matter, cation exchange capacity, exchangeable acidity, and available phosphorus. A linear increase in dry matter yield plant N uptake, and plant K uptake with harvest interval was observed for warm-season bermudagrass. For a harvest interval of six weeks and a seasonal loading rate of 194 kg N/ha, 33 kg P/ha, and 97 kg K/ha, bermudagrass production was estimated as 7.43 Mg/ha dry matter yield and plant uptake of 108 kg N/ha, 22 kg P/ha, and 53 kg K/ha. Corresponding values for winter rye were 4.25 Mg/ha, 145 kg N/ha, 23 kg P/ha, and 66 kg K/ha. The cation exchange capacity of the soil was dominated by calcium, due to calcium in the city water supply from a limestone aquifer, with only about 2% occupied by potassium. Soil pH stabilized at 7.0 in response to reclaimed water pH of 7.5. At the soil surface soil phosphorus was 90 mg P/kg soil, cation exchange capacity 3.0 meq/100 g soil, and organic matter 1%. Flexibility in management proved essential for success of the farming operation. A Farm Information Committee meets quarterly to discuss matters of mutual interest for the farm, public utility, and research.
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