1. ERDC Knowledge Core
2. Engineer Research and Development Center (ERDC)
3. Cold Regions Research Engineering Laboratory (CRREL) - (2/1/1961 - present)
4. Publication
5. Special Report

Title:	Plant growth and management for wastewater treatment in overland flow systems
Authors:	Palazzo, A. J. (Antonio J.)
Keywords:	Land treatment Overland flow Plant growth Wastewater treatment Waste water Waste treatment Water treatment Land reclamation Plants Vegetation Botany Grasses Vegetation growth Plant growth Nitrogen Phosphorus
Publisher:	Cold Regions Research and Engineering Laboratory (U.S.) Engineer Research and Development Center (U.S.)
Series/Report no.:	Special report (Cold Regions Research and Engineering Laboratory (U.S.)) ; 82-5.
Description:	Special Report Abstract: Domestic wastewater was applied over a four-year period at various rates to three overland flow test slopes to study forage grass growth and nutrient removal. The annual application rates of nitrogen and phosphorus ranged up to 2026 and 226 kg/ha, respectively. The forage grasses were harvested three times per season. Plant yields, composition and uptake of nutrients were determined. The results show that reed canarygrass, quackgrass and Kentucky bluegrass were the most persistent grasses on the slope over the four years. Perennial ryegrass was a good plant to include in seed mixtures because it became established rapidly. Tall fescue and orchardgrass persisted on the slope during the initial three years of the study and then declined after high rates of wastewater were applied during the third winter. On all wastewater-treated slopes the grasses appeared to be healthy and vigorous. The major limitations to plant growth were winter injury, the deposition of wastewater solids, the development of channels on the slopes, and the invasion of barnyardgrass, which crowded out more desirable perennial grasses. Plant yields ranged from 7.6 to 12.2 metric tons/ha and increased with increasing annual loading rates of nitrogen up to 1300 kg/ha. Yields declined at the highest loading rate of about 2000 kg/ha. Plant yields were more than three times higher than the normal hay yields in this area, but they were lower than those produced at an adjacent slow rate test site. The chemical composition of the hay was within the limits for normal plant growth, and the hay was of excellent quality. The average yield was worth $862/ha. Like nutrient uptake, biomass accumulation was greatest during the first harvest period. Plant uptake of nitrogen and phosphorus increased as the loading rates of these elements increased, and leveled off or decreased at the highest loading rate. The annual plant uptake of nitrogen and phosphorus ranged from 210 to 332 and 27 to 48 kg/ha, respectively. Nutrients were removed most rapidly during the first harvest period. The system removed 58% and 48% of the nitrogen and phosphorus applied, respectively.
Rights:	Approved for public release; distribution is unlimited.
URI:	http://hdl.handle.net/11681/12283
Appears in Collections:	Special Report