Nitrogen and Phosphorus Concentrations in Fertilized and Unfertilized Farm Ponds in Central Missouri
- 1 January 1953
- journal article
- Published by Oxford University Press (OUP) in Transactions of the American Fisheries Society
- Vol. 82 (1) , 281-288
- https://doi.org/10.1577/1548-8659(1952)82[281:napcif]2.0.co;2
Abstract
The limnology of six typical Missouri farm ponds, where fish growth rates had been determined, was investigated. Particular emphasis was directed toward a measurement of the important nutrient elements, nitrogen and phosphorus, in an effort to evaluate the processes associated with fertilization and establish the nutrient factor or factors most clearly related to fish production for Missouri ponds. Comparison of the physical and chemical data for these fertilized and unfertilized ponds suggests that the limiting factor in productivity was soluble phosphate. Yearly mean concentrations of phosphate at the surface ranged from 0.016 to 0.028 p.p.m. in the fertilized ponds and from 0.010 to 0.016 p.p.m. in the unfertilized ponds. Daily phosphorus analyses showed good correlation between concentrations of phosphate and plankton production. Each addition of fertilizer was followed by a rapid settling out which resulted in bottom phosphate concentrations which, in one pond, were as much as 10 times as great as the surface concentrations. This phosphate is confined to the bottom by a stable summer stratification in Missouri. Phosphorus added as fertilizer was found to be utilized within one week and on occasion within 24 hours depending on the degree of biological activity. The occurrence of filamentous algae was correlated with increases in light penetration and soluble phosphate. A pond with filamentous algae showed a much lowered response to fertilization suggesting a removal of nutrients due to absorption by the algal mat. Nitrogen was not limiting for algal growth in these ponds. Unfertilized ponds showed higher concentration of inorganic nitrogen than did the fertilized ponds. This increased concentration of nitrogen was attributed to the presence of the legume Lespedeza cuneata (sericea lespedeza) on the watershed of the unfertilized pond. Quantitative data on nitrogen inflow from the watersheds carrying growths of sericea lespedeza show significantly higher concentrations of inorganic nitrogen in the runoff water.This publication has 0 references indexed in Scilit: