Open AccessProduction of Sunfish Lepomis spp. in Ponds Treated with Controlled‐Release Fertilizers
Author(s) -
Kastner Richard J.,
Boyd Claude E.
Publication year - 1996
Publication title -
journal of the world aquaculture society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.655
H-Index - 60
eISSN - 1749-7345
pISSN - 0893-8849
DOI - 10.1111/j.1749-7345.1996.tb00275.x
Subject(s) - fertilizer , phosphorus , nutrient , secchi disk , zoology , biology , agronomy , controlled release , phytoplankton , ecology , chemistry , eutrophication , organic chemistry , pharmacology
.– Controlled‐release fertilizer in pond water released nutrients according to the pattern reported for exposure in soil. A single application of controlled‐release fertilizer (13% N, 13% P 2 O 5, 13% K 2 O) was compared with multiple applications of conventional, liquid fertilizer (10% N, 34% P 2 O 5 , 0% K 2 O) for augmenting sunfish production in ponds. Liquid fertilizer was used at an annual phosphorus input rate of 39.3 kg/ha; controlled‐release fertilizer was applied at 19.7, 9.8, and 4.9 kg phosphorus/ha per yr. Phytoplankton abundance inferred from chlorophyll u and Secchi disk visibility estimates and phytoplankton photosynthesis measured by the oxygen, light‐dark bottle method were similar in ponds treated with liquid fertilizer and in ponds that received controlled‐release fertilizers at the two highest rates. Net sunfish production did not differ among ponds treated with 39.3 kg phosphorus/ha in liquid fertilizer or 19.7 and 9.8 kg phosphorus/ha applied in controlled‐release fertilizer. Controlled‐release fertilizer used in this study contained more nitrogen and potassium than needed, but a custom, controlled‐release fertilizer with the proper ratio of nutrients can be made. This fertilizer would have the advantage of requiring only a single application at the beginning of the growing season, and amounts of soluble reactive phosphorus in outflow from ponds could be reduced by using controlled‐release fertilizers.