ABSTRACT
Jodelie19, BlingBling, and Burnsey are bacteriophages identified using host bacteria of the genus Gordonia Jodelie19 is a lytic phage found in Gordonia rubripertincta NRRL B-16540. The temperate phage BlingBling and lytic phage Burnsey were both isolated using the host bacterium Gordonia terrae 3612.
ABSTRACT
Research evaluating nutrient losses during the establishment of plant material in mixed residential landscapes is limited. The objectives of this study were to determine the effect of vegetative cover type, compost application, and tillage on nutrient losses during the establishment of landscape plants. Twenty-four small plots constructed with subsoil fill were planted with St. Augustinegrass [ (Walter) Kuntze] and mixed ornamental species in a randomized complete block design. Plots received composted dairy manure solids at a rate of 0 or 50.8 m ha- in combination with shallow tillage or aeration. Cumulative leachate loads and flow-weighted mean concentrations of NH-N, NO + NO-N, and dissolved reactive P (DRP) were calculated periodically and annually to assess nutrient leaching from landscape plots. Higher cumulative leachate volume, inorganic N and DRP loads, and mean NO + NO-N and DRP concentrations were observed under ornamental cover during one or more study periods, which we attribute to differences in root density and shoot biomass between mixed ornamental species and turfgrass during establishment. Greater cumulative leachate inorganic N loads were reported from composted soils than from unamended soils or soils receiving only tillage or aeration. Inorganic N and DRP loads were similar in magnitude to reported leaching losses from agricultural systems. Better management of nutrients and water in woody ornamental plant beds during plant establishment is needed due to differences in plant growth habits compared with turfgrass. Nutrient content of organic amendments should be considered when applying these materials as a soil conditioner in new residential landscapes.
Subject(s)
Phosphorus , Soil , Agriculture , Manure , Soil PollutantsABSTRACT
Our objective was to evaluate changes in water quality parameters during 1983-2007 in a subtropical drinking water reservoir (area: 7 km(2)) located in Lake Manatee Watershed (area: 338 km(2)) in Florida, USA. Most water quality parameters (color, turbidity, Secchi depth, pH, EC, dissolved oxygen, total alkalinity, cations, anions, and lead) were below the Florida potable water standards. Concentrations of copper exceeded the potable water standard of <30 µg l(-1) in about half of the samples. About 75 % of total N in lake was organic N (0.93 mg l(-1)) with the remainder (25 %) as inorganic N (NH3-N: 0.19, NO3-N: 0.17 mg l(-1)), while 86 % of total P was orthophosphate. Mean total N/P was <6:1 indicating N limitation in the lake. Mean monthly concentration of chlorophyll-a was much lower than the EPA water quality threshold of 20 µg l(-1). Concentrations of total N showed significant increase from 1983 to 1994 and a decrease from 1997 to 2007. Total P showed significant increase during 1983-2007. Mean concentrations of total N (n = 215; 1.24 mg l(-1)) were lower, and total P (n = 286; 0.26 mg l(-1)) was much higher than the EPA numeric criteria of 1.27 mg total N l(-1) and 0.05 mg total P l(-1) for Florida's colored lakes, respectively. Seasonal trends were observed for many water quality parameters where concentrations were typically elevated during wet months (June-September). Results suggest that reducing transport of organic N may be one potential option to protect water quality in this drinking water reservoir.
