Małgorzata Bonisławska

Application of ceramic membranes for microalgal biomass accumulation and recovery of the permeate to be reused in algae cultivation.

The present study was carried out to investigate the possibility of using ceramic membranes for microalgal biomass densification and to evaluate the qualitative composition of the permeate as a source of nitrogen and phosphorus for microalgae cultivated in a closed system. The studies were conducted on the microalga Monoraphidium contortum. The microfiltration process was carried out on a quarter-technical scale using ceramic membranes with 1.4 μm, 300 and 150 kDa cut-offs. Permeate flux and respective hydraulic resistances were calculated. Dissolved inorganic nitrogen and phosphorus fractions were measured in the feed and the permeate. It was noted that the permeate flux in the MF process was decreasing while the values of reversible and irreversible resistances were increasing as the cut-off of the studied membranes was diminishing. An analysis of the hydraulic series resistance showed that using a 300 kDa membrane would be the most beneficial, as it was characterized by a comparatively high permeate flux (Jv=1.68 10(-2)m(3)/m(2)s), a comparatively low susceptibility to irreversible fouling (1.72·10(9) 1/m) and a high biomass retention coefficient (91%). The obtained permeate was characterized by high concentrations of dissolved nitrogen and phosphorus forms, which indicated that it could be reused in the process of microalgal biomass production.

Effect of the coagulants PAX and PIX on the embryonic development of pike (Esox lucius L.)

Abstract The study examined the development of pike (Esox lucius L.) roe in water containing variously concentrated coagulants PIX®113 and PAX®18, which are increasingly being used in Poland as a method of lake reclamation. The genital products came from spawners caught from a natural water body (Lake Przybiernów). The eggs were incubated in water taken from the same lake, and subjected to the process of phosphorus and iron precipitation with coagulants. Based on the results, it was found that the coagulants used in the experiment inhibit the embryogenesis of pike by the formation of aggregates falling to the bottom, reducing the percentage of live embryos and affecting the size and malformation of the hatching larvae.

The application of ceramic membranes for treating effluent water from closed-circuit fish farming

Abstract The aim of the study was to analyze and assess the possibility of using a two-stage filtration system with ceramic membranes: a 3-tube module with 1.0 kDa cut-off (1st stage) and a one-tube module with 0.45 kDa cut-off (2nd stage) for treating effluent water from a juvenile African catfish aquaculture. The study revealed that during the 1st filtration stage of the effluent water, the highest degrees of retention were obtained with respect to: suspended solids SS (rejection coefficient RI=100%), turbidity (RI=99.40%), total iron (RI=89.20%), BOD5 (RI=76.0%), nitrite nitrogen (RI=62.30%), and CODCr (RI=41.74%). The 2nd filtration stage resulted in a lower reduction degree of the tested indicators in comparison to the 1st filtration stage. At the 2nd stage, the highest values of the rejection coefficient were noted in for the total iron content (RIV=100%), CODCr (RIV=59.52%; RV=64.28%, RVI=63.49%) and turbidity (RIV and RV = 45.0%, RVI=50.0%). The obtained results indicate that ceramic membranes (with 1.0 and 0.45 kDa cut-offs) may be used in recirculation aquaculture systems as one of the stages of effluent water treatment.

Peculiarities of embryonic development of round goby Neogobius melanostomus (Gobiidae) in fresh water

The results obtained indicate the potential of the round goby to reproduce in fresh water, which may result in further expansion of the species to upper reaches of rivers and to other water bodies (lakes, dam reservoirs). Embryonic development of the round goby in fresh water proceeded in a regular manner. However, embryonic development in fresh water took a shorter time than in saline water. Although the newly hatched larvae were somewhat smaller than those hatching from eggs kept in saline water, the hatching rate was high (90%). If the species finds conditions suitable for reproduction in Polish freshwater bodies, it may pose a threat to numerous native freshwater fish species by taking over both their feeding and reproductive niches.

Water salinity effects on embryogenesis of the lesser sandeel, Ammodytes tobianus (Linnaeus, 1758)

Effects of water salinity (3.0–9.0 PSU) on the duration and outcome of embryogenesis in the lesser sandeel (Ammodytes tobianus (L.) as well as on survival, size, and malformation rate of the newly hatched larvae were followed, based on observations involving equipment consisting of a microscope and still and digital cameras. The images obtained and measurements of egg and larval dimensions were analyzed using the NIS elements Br. computer software package. The lowest salinity tested (3.0 PSU), similar to that in the inshore Baltic Sea waters native for the species studied, produced a lower fertilization rate and resulted in extended embryogenesis, reduced embryo survival, changes in the hatch size, and increased larval malformation rate. The high-end salinity (7.5–9.0 PSU), higher than that prevailing in the species’s spawning grounds in the Baltic Sea, resulted — similarly to the low-end salinity — in disturbed development and growth of the embryos.

The effect of effluents from rainbow trout ponds on water quality in the Gowienica River / Wpływ zrzutu wód poprodukcyjnych ze stawów pstrągowych na jakość wody w rzece Gowienicy

Abstract Fish farming and especially rearing and breeding of rainbow trout and carp is one of potential sources of surface water pollution. The study was aimed at assessing the effect of a rainbow trout farm on water quality in the Gowienica River in winter. Temperature, pH, electrolytic conductivity, total suspended solids, dissolved oxygen, BOD5, CODCr, alkalinity, water hardness, calcium, magnesium, ammonium-nitrogen, nitrate-nitrogen (III and V) and total phosphorus were determined according to Polish Norms and APHA [1995] in water samples collected in winter up- and downstream the study object. The increment of pollutant concentrations in rainbow trout farm effluents was referred to the requirements in Rozporządzenie MŚ [2006]. Performed studies and literature review show that effluents from the assessed fish farm did not worsen water quality of the river. Increased concentrations of total suspended solids and CODCr in effluents were noted only in March. According to data from the report on environmental status in zachodniopomorskie province in the years 2008-2011, poor water quality of the Gowienica River is recorded already upstream the rainbow trout farm. Pollution of this stretch of the river may originate from uncontrolled waste water management and from nutrient runoff from fields. STRESZCZENIE Jednym z potencjalnych źródeł zanieczyszczenia wód powierzchniowych jest gospodarka rybacka zajmująca się głównie chowem i hodowlą pstrąga tęczowego i karpia. Celem pracy była ocena wpływu działalności gospodarstwa pstrągowego na jakość wód Gowienicy w sezonie zimowym. W okresie zimowym w pobranych próbkach wody w punktach powyżej i poniżej obiektu oznaczano następujące wskaźniki: temperaturę, pH, przewodność elektrolityczną, zawiesinę ogólną, tlen rozpuszczony w wodzie, BZT5, ChZTCr, zasadowość, twardość, wapń, magnez, azot amonowy, azot azotanowy (III) i (V), fosfor ogólny - zgodnie z wybranymi Polskimi Normami i zaleceniami APHA [1995]. Określano przyrost zanieczyszczeń w wodach poprodukcyjnych z hodowli pstrągów, który odnoszono do wymogów zawartych w Rozporządzeniu MŚ [2006]. Jak wynika z przeprowadzonych badań oraz z przeglądu literatury, wody poprodukcyjne pochodzące z działalności ocenianego gospodarstwa rybackiego nie wpływały na pogorszenie jakości wody badanej rzeki. Uzyskane w pracy wyniki wykazały przyrost stężenia zawiesin ogólnych i ChZTCr, w wodach poprodukcyjnych tylko w marcu. Zgodnie z danymi zawartymi w raportach o stanie środowiska w woj. zachodniopomorskim w latach 2008-2011, niezadowalająca jakość wód Gowienicy jest notowana już na odcinku powyżej gospodarstwa pstrągowego. Źródłem zanieczyszczeń występujących na tym odcinku Gowienicy może być nieuregulowana gospodarka kanalizacyjna w gminie, jak również spływy składników biogennych z pól.

Specifying the relationship between key stages of pike (Esox lucius L.) embryogenesis and coagulants used in lake recultivation

Abstract The study focused on the effect of iron and aluminium coagulants (PIX®113, PAX®18) commonly used for purification of open waters on key stages of embryonic development of pike (Esox lucius L.). Fertilized pike roe was incubated in lake water and in water with the admixture of coagulants, applied in the concentration of 50.0 mg dm-3 at selected stages of embryogenesis: blastopore closure, inoculation, and the hatching of larvae. In the course of the experiment, live embryos were observed and total lengths of the larvae were measured. Simultaneously, selected hydrochemical indicators were gauged. It was discovered that coagulants had the strongest effect at the first stage of embryogenesis (the end of the process of gastrulation). At that stage the survival rate of embryos was the lowest (73.5- 75.0%) and the percentage of deformities in the hatched larvae was the highest (9.7-10.0%).