Evaluation of the primary production of the summer fishpond I, within the Malina fish farm, Galati County

Abstract

This work aims to assess the productivity of the summer I juvenile rearing pond and the water quality at the Malina Fish Farm, Galati County. Various physico-chemical and biological parameters are related, and overall water quality depends on deviations from the allowed range. During the monitoring of the physico-chemical parameters, the water quality in the summer I juvenile rearing pond, within the Mălina fish farm, was within the allowed and recommended limits for waters used in fish farming, the water falling into the II quality category. In nutrient-rich waters - generally rich in phosphorus and nitrogen - chlorophyll levels tend to be high. These nutrients encourage algal blooms, which can deplete dissolved oxygen as the algae die and decompose - a major factor in fish mortality. The level of quantitative development of phytoplankton as a direct result of ecological conditions and interactions, and primarily of trophic ones, through the amount of chlorophyll can be considered a measurable and objective indicator of these characteristics. The quantitative analysis of the photosynthetic pigment showed that the photosynthetic potential is higher in the vegetative season (the concentration of chlorophyll a plus the concentration of pheophytin fell within the range of 22.374-36.681 mg/l) and according to the normative the pond is eutrophic. The eutrophic basin is characterized by high trophicity, a lower water transparency (well-developed plankton) and good biological production. The gross production being 4.08 mg/l.