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1

The effect of fish waste and duck manure on the growth and yield of pak choi

Idris Muhammad, Bangun Imam H., Ani Nurma, Hutagaol Dermawan, Siddik Fajar

Journal of Water and Land Development

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2023

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no. 59

100--107

EN

In 2021, pak choi production in Indonesia was 727.47 Mg, marking an increase of 8.2% compared to the 2020 production, which was 667.47 Mg. Therefore, there is a clear need for cultivation improvement, particularly through the implementation of organic fertilisers. This study aimed to investigate the impact of liquid organic fertiliser (LOF) derived from fish waste and duck manure on the growth and yield of the pak choi plant (Brassica rapa. L. var. Nauli F1). A randomised block design factorial was used with two factors and three replications. The first factor considered was LOF from fish waste, comprising three levels (LOF0= control, LOF1= 25 cm3∙dm-3 of water, and LOF2= 50 cm3∙dm-3 of water). The second factor focused on duck manure fertiliser (DMF) and involved four levels (DMF0= control, DMF1= 3.7 kg∙plot-1, DMF2= 5.55 kg∙plot-1, and DMF3= 7.4 kg∙plot-1). The results showed that the application of LOF from fish waste positively influenced the growth and yield of pak choi, with the most effective treatment observed in LOF1(25 cm3∙dm-3 of water). However, the application of DMF did not yield a significant difference in its effect on the growth and yield of the pak choi plant. The control treatment (DMF0) reported comparable results and the combination of LOF from fish waste and DMF did not show a significant effect, with the most favourable findings observed in the LOF2DMF0 treatment (50 cm3∙dm-3 and control).

2

Seasonal characteristics of nutrient and nutrient structure in the Yangtze River estuary

Li Lei, Xv Guodong, Zheng Yingjie, Jiang Mei

Archives of Environmental Protection

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2023

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Vol. 49, no 3

115--122

EN

This data article aimed to evaluate the influencing mechanisms of the nutrients and the level of eutrophication in the Yangtze River estuary. The seasonal characteristics of nutrients (dissolved inorganic nitrogen (DIN), SiO3-2–Si, and PO43-P) in the seawater of the Yangtze River estuary were analyzed by conducting surveys in spring and summer of 2019. The findings revealed that the concentrations of all nutrient at the surface and bottom layers were lower in spring compared to summer. NO3–N was typically the major form of DIN. Runoff was identified as the primary source of DIN and SiO32−–Si, while PO43−–P originated from a various sources. The SiO32−–Si, while PO43−–P values in the surface and bottom layers during the spring and summer were higher than the Redfield values, indicating an imbalanced nutrient distribution. Furthermore, discrepancies were observed in the distributions of DIN/PO43−–P, SiO32−–Si/DIN, and SiO32−–Si/PO43−–P in the Yangtze River estuary. Through an examination of the ratio of DIN/PO43−–P absorbed by phytoplankton, PO43−–P was identified as a potential limiting factor for nutrition in the sea area of the Yangtze River estuary during spring and summer. The Eutrophication Index (E) values for both spring and summer were found to be higher than the eutrophication threshold, indicating severe eutrophication in the studied sea area.

3

Multivariate approach to evaluate the factors controlling the phytoplankton abundance and diversity along the coastal waters of Diu, northeastern Arabian Sea

Kumar Ponnusamy Sathish, Venkatnarayanan Srinivas, Pandey Vikas, Ratnam Krupa, Jha Dilip Kumar, Rajaguru S., Dharani Gopal, James Rathinam Arthur, Atmanand Malayath Aravindakshan

Oceanologia

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2022

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No. 64 (2)

267--275

EN

The present study investigated the phytoplankton assemblage and diversity with physicochemical parameters of Diu coastal waters in different seasons during 2018–19. During the study period, 61 phytoplankton species comprising diatoms (50 sp.), dinoflagellates (8 sp.), and cyanophyceae (3 sp.) were recorded. Diatom was found to be a major community and contributed 79 to 99% of total phytoplankton abundance. Reduction in dinoflagellate and dominance of pennate-diatoms were observed during the monsoon. Chlorophyll-a concentration also showed a similar trend and decreased during the monsoon. However, the phytoplankton abundance was low particularly during the monsoon which might be due to the elevated total suspended solids (TSS) load. Canonical correspondence analysis revealed that diatoms were able to survive in high TSS with the support of high nutrients; while dinoflagellates were limited due to those conditions. Overall, the reduction in phytoplankton abundance, diversity, and biomass was recorded due to the elevated TSS input along the coastal waters of Diu.

4

Reducing Nitrate and Phosphate Concentrations in Shrimp Wastewater Aquaculture Using Gelidium corneum

Indraswari Nabila, Adharini Ratih Ida

Ecological Engineering & Environmental Technology

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2022

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Vol. 23, iss. 5

137--144

EN

Shrimp culture wastewater contains residual feed and shrimp metabolism. Shrimp wastewater if not managed properly will be harmful to the long term viability of the farming itself and threatens environmental sustainability. This study aims to determine the potential and effectiveness of Gelidium corneum with different densities as a biofilter for vaname shrimp culture waste. This study used a completely randomized design method consisting of 3 treatments and 3 replications using different density treatments, namely T1 (1 gL-1); T2 (2 gL-1); and T3 (3 gL-1) in an aquarium volume of 30 L. The parameters observed included the concentration of nitrate, phosphate, temperature, TDS, TSS, salinity, DO, pH. Absorption effectiveness and growth of G. corneum were measured at the beginning and end of the study. G. corneum is able to reduce the concentration of phosphate in water is higher than lowering the content of nitrate. G. corneum with a density of 1 gL-1 showed the best performance in absorbing nitrate by 8% on day 15. While the 2 gL-1 treatment was able to reduce the phosphate concentration by 92% in 25 days. Absorption of Total Nitrogen content in the thallus obtained in the treatment of 2 gL-1 was 32% and total phosphate was 58% for 25 days. Therefore G. corneum can be used as a candidate for commodity in Integrated Multi Trophic Aquaculture (IMTA).

5

Nutrient Determinant Factor of Causing Algal Bloom in Tropical Lake (Case Study in Telaga Menjer Wonosobo Indonesia)

Piranti Agatha S., Wibowo Dwi N., Rahayu Diana R. U .S.

Journal of Ecological Engineering

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2021

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Vol. 22, nr 5

156--165

EN

Nutrients are substances that are used by living organisms in the growth and survival of organisms. On the basis of this background, the aim of this study was to assess the concentration of nutrients (macro and micronutrients) and chlorophyll in the Menjer lake and to examine the relationship between nutrient concentration and algal biomass to identify the determinants of algal development in tropical lakes (Menjer Lake Wonosobo, Indonesia). The research was conducted using a survey method at Menjer Lake Wonosobo. Observations and sampling were carried out 3 times with intervals of 1 month at 7 locations in the photic zone. The concentrations of macronutrients and micronutrients in the Menjer Lake were spatially even in all locations and the temporally slightly increased concentrations were relatively the same during the measurement period. The Cu, NO2, Si, and Na macronutrients are the determining factors for algal blooming in Menjer Lake Wonosobo. The effect of Cu, NO2 and Si concentrations was inversely related to the algal abundance, while the Ca, Na and Mo concentrations were in line with the abundance of algae.

6

Changes in Selected Water Quality Indicators of the Warta River Due to the Jeziorsko Dam Reservoir

Hämmerling Mateusz, Spychała Marcin, Walczak Natalia, Stachowski Piotr, Nguyen Thanh Hung

Rocznik Ochrona Środowiska

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2020

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Tom 22, cz. 2

1044--1057

EN

Many factors affect the quality of water in rivers, including: types of pollution sources, the shape of the catchment, the type of land use, the amount of pollution flowing in. The construction of a retention reservoir is one of the factors affecting changes in the river valley related to the landscape, the environment, and water flow hydraulics. Reducing the velocity of water flow on the section of the reservoir causes changes in the characteristics of the movement of pollutants, some of them are deposited in the reservoir. The article analyzes water quality parameters at intake points located below (Uniejów) and above (Biskupice) of the Jeziorsko dam on the Warta River. The variability of such parameters as BOD5, TOC, pH, temperature, Ntot, Ptot was analyzed. The research also analyzed the dynamics of water inflow and outflow from the reservoir. The actual water retention time in the reservoir, which makes interpretation of the results difficult. The most indicators were characterized by the significance of differences for research in 2014.

PL

Na jakość wody w rzekach wpływa wiele czynników do których należą: rodzaje źródeł zanieczyszczeń, ukształtowanie zlewni, rodzaj użytkowania terenu, ilość dopływających zanieczyszczeń. Budowa zbiornika retencyjnego jest jednym z czynników wpływających na zmiany w dolinie rzecznej związane z krajobrazem, środowiskiem, hydrauliką przepływu wody. Zmniejszenie prędkości przepływu wody na odcinku zbiornika powoduje zmiany w charakterystyce przemieszczania się zanieczyszczeń, część z nich osadza się w zbiorniku. W artykule przeanalizowano parametry jakości wody w punktach poboru zlokalizowanych poniżej (Uniejów) i powyżej (Biskupice) zapory zbiornika Jeziorsko na rzece Warcie. Analizie poddano zmienność takich parametrów jak BZT5, OWO, pH, temperatura, Nog, Fog. W badaniach przeanalizowano również dynamikę dopływu i odpływu wody ze zbiornika. Rzeczywisty czas retencji wody w zbiorniku jest różny co utrudnia interpretację wyników. Najwięcej wskaźników charakteryzowało się istotnością różnic dla badań w 2014 roku.

7

Response of the rotifer community to human-induced changes in the trophic state of a reservoir

Kim Seong-Ki, Kim Jeong-Cheol, Joo Jeong-Cheol, Choi Jong-Yun

Oceanological and Hydrobiological Studies

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2020

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Vol. 49, No. 4

329--344

EN

Human disturbance and nutrient runoff lead to water pollution, particularly in downstream waters and reservoirs. We hypothesized that increased human activity in summer would affect the trophic state of downstream reservoirs, affecting the interannual species composition of rotifers. We used long-term data for the Unmun Reservoir in South Korea (2009–2015), which is increasingly affected by human activity. The interannual variation of nitrogen and phosphorus levels was higher in summer and autumn, resulting in eutrophication. This led to a change in species composition of rotifers. Anuraeopsis fissa, Brachionus calyciflorus and Trichocerca gracilis were abundant in the most eutrophic state, while high densities of Ascomorpha ovalis and Ploesoma hudsoni were observed when nutrient concentrations were lower. The trophic state changes in the Unmun Reservoir were largely attributed to summer human activity in tributary streams. Our study location is typical of the stream network in South Korea and we assume that similar trophic state changes in reservoirs will be common. Changes in the density and species diversity of rotifers due to eutrophication indicate the need for active management and conservation, including the restriction of human activity around streams.

8

Seasonal influence of physico-chemical parameters on phytoplankton diversity, community structure and abundance at Parangipettai coastal waters, Bay of Bengal, South East Coast of India

Manigandan V., Yosuva M., Saravanakumar A., Machendiranathan M.

Oceanologia

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2018

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No. 60 (2)

114--127

EN

The present investigation studied the seasonal variation between physico-chemical parameters and phytoplankton diversity, community structure and abundance; quantitative samples were collected on a monthly basis from April 2015 to March 2016 at Parangipettai coast, the Bay of Bengal (BOB). Statistical analyses were performed on physico-chemical parameters such as salinity, dissolved oxygen (DO), pH, temperature, nitrate, nitrite, silicate, and inorganic phosphate (IP). The significant (P < 0.0005) variation among seasons as well as a high influence of these parameters was observed on phytoplankton productivity. Totally, 117 species were identified, belonging to five different classes, Coscinodiscophyceae (62%), Bacillariophyceae (17%), Fragilariophyceae (8%), Dinophyceae (8%) and Cyanophyceae (5%). Throughout the study period, the occurrence of most dominant species was observed from class Coscinodiscophyceae and Bacillariophyceae. The phytoplankton species also showed significant changes according to seasonal variations as well as the nutrient availability. Phytoplankton attained their maximum population density during premonsoon; whereas minimum population was observed during monsoon. The performed statistical analysis on phytoplankton species, the Shannon & Wiener diversity index was found to be higher during postmonsoon and lower during monsoon season. The Canonical Correspondence Analysis (CCA) was used, to find out the seasonal relationship between phytoplankton and physicochemical parameters. Hence, the executed CCA results revealed that temperature, salinity, silicate, DO and IP have a higher influence on phytoplankton abundance.

9

Identifying the main sources of silicate in coastal waters of the Southern Gulf of Valencia (Western Mediterranean Sea)

Sospedra J., Niencheski L. F. H., Falco S., Andrade C. F. F., Attisano K. K., Rodilla M.

Oceanologia

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2018

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No. 60 (1)

52--64

EN

Silicon is a major nutrient for siliceous primary producers, which can become a potential limiting nutrient in oligotrophic areas. Most of the silicon inputs to the marine environment come from continental discharges, from both superficial and ground waters. This study analyses the main sources of silicon and their dynamics along the southernmost 43 km of shoreline in the Gulf of Valencia (Western Mediterranean Sea). The salinity and silicate concentration in the different compartments (springs, freshwater wells, beach groundwater, surf zone and coastal waters) in this coastal area were determined. In addition, chlorophyll a and phytoplankton community were analyzed in the surf zone and coastal waters. Silicate concentrations in freshwater wells ranged between 130 and 150 μM, whereas concentrations of this nutrient declined to 49 μM in freshwater-seawater mixture transects. At the same time, there was a positive gradient in silicate for both freshwater and coastal waters southward. An amount of 18.7 t of dissolved silicate was estimated in the nearest first kilometre nearest to the coastline, 6 t of this silicate belonged to the background sea level. On the other hand, the sum of the main rivers in the area supplies 1.6 t of dissolved silicate per day. This implies that a large amount of the remaining 11.1 t must derive from submarine groundwater discharges, which would thus represent 59% of the coastal dissolved silicate budget. Overall, it is suggested that a subterranean transport pathway must contribute considerably to silicate concentrations throughout this zone, which is characterized as permeable.

10

Zawartość substancji biogennych w wodach wybranych akwenów województwa opolskiego

Cygan A.

Prace Instytutu Ceramiki i Materiałów Budowlanych

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2016

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R. 9, nr 26

19--25

PL

Do substancji biogennych zaliczamy wszystkie pierwiastki niezbędne do rozwoju żywych organizmów, przede wszystkich związki azotu i fosforu. Rozwój gospodarczy i ingerencja człowieka przyczynił się do wysokiego zużycia tych substancji, czego następstwem jest zwiększenie żyzności wód oraz ich nadmierne starzenie się, czyli eutrofizacja. Procesy te w konsekwencji prowadzą do zwiększonego rozwoju glonów i zakwitu wód. Przeprowadzone badania miały na celu określenie zawartości substancji biogennych w akwenach zlokalizowanych na terenie województwa opolskiego. Na obecnym etapie badań stwierdzono, że w przeanalizowanych wodach nie odnotowano przekroczeń stężeń biogenów uznanych za maksymalne dla badanych akwenów.

EN

To include all the nutrients and mineral elements essential to the development of living organisms, primarily nitrogen and phosphorus compounds. Economic development and human interference caused excessive growth of these substances, which results in increasing the fertility waters and their aging or excessive eutrophication. These processes therefore lead to an increased growth of algae blooms and water. The study aimed to determine the content of biogenic substances in waters located in the province of Opole. At the current stage of research, it was found that the waters affected by the eutrophication outweigh the concentration of nitrates and phosphates, while in the waters of pure concentration falls within the scope of the regulation.

11

Efektywność reaktorów wielofazowych z osadem czynnym w świetle doświadczeń eksploatacyjnych

Mucha Z.

Logistyka

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2015

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nr 3

3381--3386, CD 1

PL

W artykule przedstawiono wyniki analiz i badań eksploatacyjnych oraz warunki pracy wybudowanych w ostatnich latach gminnych oczyszczalni ścieków z wielofazowymi reaktorami osadu czynnego w układzie przepływowym. Oczyszczalnie te zapewniają wysoką efektywność usuwania zarówno związków organicznych jak i biogennych i przy prawidłowej eksploatacji spełniają zaostrzone wymagania dyrektywy dotyczącej oczyszczania ścieków komunalnych. Analiza pracy przedstawiona została na przykładzie trzech obiektów o porównywalnych rozwiązaniach technologicznych i różnym obciążeniu ładunkiem zanieczyszczeń. We wnioskach przedstawiono również doświadczenia eksploatacyjne z innych oczyszczalni z reaktorami wielofazowymi.

EN

The article presents operation parameters and conditions as well as treatment results of communal wastewater treatment plants. The plants have been built in recent years and they all have multi-phase activated sludge reactors (BNR reactors) working in a continuous flow mode. The plants provide a very good removal of both organic compounds and nutrients and meet the stringent requirements of the Directive on Urban Wastewater Treatment, if properly operated. The analysis covers three case studies of comparable technological systems and different pollution loads. In the conclusions the authors included also operational experiences from other treatment plants with multi-phase reactors.

12

Environmental application of electrical discharge for ozone treatment of soil

Abiru T., Mitsugi F., Ikegami T., Ebihara K., Aoqui S.-I., Nagahama K.

Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska

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2015

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nr 4

42--44

EN

In this study, influence of ozone treatment on physical properties of soil was investigated. We used a quartz container for ozone treatment of soil. The amount of soil used for treatment was 100 g. Treating time was 90 minutes. Flow rate of ozone gas was 1.5 L/min. We measured characteristics of soil such as inorganic nutrient (NO3-N, NO2-N, and NH4-N), pH(H2O), fungi, DNA of soil, and exchangeable bases (Ca, K, Fe, and Al) before and after ozone treatment.

PL

W niniejszym opracowaniu, opisano badania wpływu obróbki ozonem na własności fizyczne gleby. Do ozonowania gleby wykorzystaliśmy pojemnik kwarcowy. Ilość gleby poddanej działaniu ozonu wynosiła 100g, a czas oddziaływania 90 minut. Przepływ ozonu wyniósł 1.5l/min. Mierzono właściwości gleby, takie jak nieorganiczne składniki odżywcze (NO3-N, NO2-N i NH4-N), pH(H2O), grzyby, DNA w glebie i zasady wymienne (Ca, K, Fe i Al) przed i po poddaniu jej działaniu ozonu

13

Rola łożyska ludzkiego w analityce ksenobiotyków

Płotka J., Narkowicz S., Polkowska Ż., Namieśnik J.

Analityka : nauka i praktyka

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2014

|

nr 1

36--40

PL

Łożysko stanowi ważny organ, który umozliwia transport substancji odżywczych od matki do dziecka. W przypadku narażenia kobiety ciężarnej na substancje toksyczne w tym używki, w trakcie ciąży przez łożysko migrować mogą również substancje szkodliwe dla płodu, które mogą wywołać zaburzenia w jego rozwoju.

14

Rozpraszanie składników nawozowych z żywności traktowanej jako odpad

Sapek A.

Woda-Środowisko-Obszary Wiejskie

|

2013

|

T. 13, z. 1

129--142

PL

Środki spożywcze wytworzone w rolnictwie są tylko częściowo konsumowane przez człowieka. Raport Komisji Europejskiej przyjmuje, że łącznie w handlu i gospodarstwach domowych krajów Unii Europejskiej ok. 11% masy towarowej żywności przeznaczonej do spożycia ulega zmarnowaniu i jako odpad jest wyrzucana. Inne źródła podają, że udział wyrzucanej żywności jest jeszcze większy i wynosi do 50% gotowych wytworów z rolnictwa. Do wyprodukowania żywności, która jest następnie wyrzucana, potrzebne są dodatkowo odpowiednie ilości wody, energii i materiałów. Aby wyprodukować w 27 państwach Unii Europejskiej w 2010 r. ok. 30% marnowanej żywności niezbędne było nawożenie mineralne odpowiadające w przybliżeniu w mln t ·r- ¹: 3,2 N, 0,47 P i 1,1 K. Odpady wyrzucone na wysypisko śmieci lub do kanalizacji rozkładają się, co wiąże się z uwalnianiem azotu i fosforu, które ulegają rozproszeniu do środowiska.

EN

Foodstuff produced in agriculture is only partly consumed by humans. A report of European Commission (DG ENV) stated that about 11% of food designed for human consumption is wasted in retail and household and thrown away to dumping places or to sewerage. Other sources estimate food losses at up to 50% of trade mass. To produce food which is then wasted in 30%, adequate amount of water, energy and materials should be used. For this purpose, 3.2 million t N, 0.47 million t P and 1.1 million t K in fertilizers were applied in 27 member countries of the EU in the year 2010. Food waste thrown to dumping places or sewerage decompose and release nitrogen and phosphorus that are dispersed in the environment.

15

Starch and nutrient contents are key for mosses adapting to different succession stages along a receding glacier

Sun S.-Q., He G., Wu Y.-H., Zhou J., Yu D.

Polish Journal of Ecology

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2013

|

Vol. 61, nr 2

233--239

EN

Mosses are the pioneer and the first green land plants developed during the evolutionary process, they play an important role in the development of soil, biogeochemical cycling and facilitating plant colonization. Although species richness, composition, diversity and cover of moss communities vary, they grow well almost in all forests. Why mosses can grow in different conditions? What are the adaptive strategies of mosses in different forests along primary succession sequences? It is not still completely clear. In order to answer these questions, nutrient and carbohydrate accumulation in mosses were tested along the primary succession following deglaciation of Hailuogou glacier, Gongga Mountain, China. Nitrogen (N), phosphorus (P), potassium (K) content, total organic carbon (TOC), soluble sugar and starch accumulated in the dominant moss species were determined and compared. TOC increased insignificantly with forest age. N, P, K contents in mosses were significantly higher in forests with dense shrubs, where N content was seperately 1.69% in A. hookeri and 1.35% in P. schreberi in 30 yr aged forest, P content in 30 yr and 52 yr aged forest was seperately 0.022% and 0.020% in A. hookeri and 0.020% and 0.017% in P. schreberi, and K content in 30 yr and 52 yr aged forest was seperately 0.570% and 0.553% in A. hookeri and 0.490% and 0.493% in P. schreberi. Soluble sugar was higher in the early stage of succession, but the opposite was observed for starch and nonstructure carbohydrate content, which was lower in early successional stage. Mosses adopted different adaptive strategies in different aged forests along receding glacier, in which starch and N, P, K contents were key for adaptiation. That is, mosses accumulated much more starch in the severe environment of early succession stage. In more favourable environment, N, P, K was found to be accumulated for plant growth.

16

Influence of climate parameters on long-term variations of the distribution of phytoplankton biomass and nutrient concentration in the Baltic Sea simulated by a 3D model

Dzierzbicka-Głowacka L., Piskozub J., Jakacki J., Janecki M., Nowicki A.

Polish Journal of Ecology

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2012

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Vol. 60, nr 4

651--666

EN

We used a 3-D coupled seaice ecological model of the Baltic Sea to investigate the influence of long-term trends in average temperature, wind speed and solar irradiance on nutrients concentration and distribution of phytoplankton. We tested the sensitivity of the model to changes of the main physical parameters such as temperature, wind speed, solar and thermal radiation performing several numerical experiments with different configurations. Discussion about the relevance of the results for the expected future climate change is provided. The calculations were done for whole Baltic Sea for the period from 2004 to 2048. The results of the numerical simulations for the different areas of Baltic Sea (nine stations: Gulf of Gdańsk, Gdańsk Deep, Gotland Deep, Bornholm Deep, Gulf of Finland, Gulf of Riga, Gulf of Bothnian, Bothnian Sea, Danish Straits) were presented. The simulations results show significant changes in phytoplankton biomass and nutrient concentration distributions, which took place in the regions where a significant increase in currents (to 100 cm s-1) was found. The results of the numerical simulations for five years (2000–2004) are consistent with in situ observations for temperature and phytoplankton (Dzierzbicka-Glowacka et al. 2011b).

17

Numerical simulations of marine zooplankton dynamics and its interaction with other system components

Dzierzbicka-Głowacka L.

Polish Journal of Ecology

|

2001

|

Vol. 49, nr 1

3-18

EN

This paper presents the numerical simulations of the influence of the zooplankton dynamics on the phytoplankton, zooplankton and nutrient biomasses in the sea. The numerical studies were carried out using a phytoplanktonzooplankton-nutrient-detrius PhyZooNuDe biological upper layer model with a full-developed regeneration mechanism and with regarding daily migration of zooplankton. In this model the zooplankton is treated not as "biomass" but as organisms having definite patterns of growth, reproduction, and mortalityassuming, also {Zoop} is composed of (i) cohorts of copepods with weights (W[i]) and numbers (Z[i]); then {Zoop} = SigmaW[i]Z[i]. The PhyZooNuDe model consists of three coupled, partial second-order differential equations of the diffusion type for phytoplankton, zooplankton, nutrients and one ordinary first-order differential equation for benthic detritus pool, together with initial and boundary conditions. The calculation were made for 35 days in an area 0 mniejsze lub równe z mniejsze lub rowne 20m with a vertical space step of 10 cm and a time step of 5 min. The experimental data, gathered during the PEX'86 international scientific experiment of the Baltic states, and subsequently by the International Council for the Exploration of the Sea, were used as the input data for the calculations. The simulation given here demonstrated as factors of grazing, growth, metabolism, reproduction, and mortality of copepods are important since can alter the nature of the interactions of plants and herbivores.

18

An algorithm for calculating the concentration of phytoplankton in a stratified sea with respect to the daily migration of zooplankton. Part 2. Numerical simulation

Dzierzbicka-Głowacka L., Zieliński A.

Oceanologia

|

1998

|

No. 40 (4)

371-398

EN

The numerical studies were carried out using a (nutrient-phytoplankton-zooplankton-detritus) biological model with a well-developed regeneration block. This paper presents the time-dependent vertical distributions of biological characteristics (concentrations nutrients, phytoplankton and zooplankton and benthic detritus pool) on the assumption that the horizontal distribution of these parameters is uniform. The calculations were made in an area 0 ≤z≤ 20 m with a vertical scale step of 10 cm and a time scale step of 15 min. The experimental data, gathered during the PEX '86 international scientific experiment of the Baltic states, and those by the International Council for the Exploration of the Sea, were used as the input data for the calculations.

19

An algorithm for calculating the concentration of phytoplankton in a stratified sea with respect to the daily migration of zooplankton. Part 1. P–V–Z–D model

Dzierzbicka-Głowacka L., Zieliński A.

Oceanologia

|

1998

|

No. 40 (4)

355-370

EN

This paper presents a nutrient-phytoplankton-zooplankton-detritus biological model with a fully-developed regeneration mechanism with respect to the daily migration of zooplankton. The P-V-Z-D model consists of two partial differential equations of the diffusion type for the concentration of nutrients and phytoplankton, and two ordinary differential equations for the concentration of zooplankton and the benthic detritus pool, together with initial and boundary conditions.