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1

Phytoplankton assemblage of a solar saltern in Port Fouad, Egypt

100%

Madkour F. F. , Gaballah M. M.

Oceanologia

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2012

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tom No. 54 (4)

687-700

EN

The present study is the first investigation of the phytoplankton community in one of Egypt's saltworks. The phytoplankton composition and distribution in five ponds of increasing salinity were investigated in the solar saltern of Port Fouad. The phytoplankton community consisted of 42 species belonging to cyanobacteria (16), diatoms (12), dinoflagellates (11), Euglenophyceae (2) and Chlorophyceae (1). The number of species decreased significantly and rapidly with increasing salinity, varying between 33 species in the first pond (P1) and one species in the crystallizer pond (P5). Conversely, the total phytoplankton density, except that recorded in P1, increased significantly with rising salinity, fluctuating between 8.7 and 56 × 10^5 individuals l-1 in P2 and P5 respectively. In spite of the local variations in climate and nutrient availability, the phytoplankton composition, density and spatial variations along the salinity gradient were, in many respects, very similar to what has been observed in other solar saltworks. The pond with the lowest salinity (P1 - < 52 g l-1) was characterized by a significant diversity and blooming of diatoms and dinoflagellates. Intermediate salinity ponds (P2 and P3) with salinity ? 112-180 g l-1 exhibited a decline in both species richness and density, but the stenohaline blue green algae ( Synechocystis salina) did flourish. The highly saline concentrating ponds and crystallizers (P4 and P5) with salinity ~ 223-340 g l-1 were characterized by few species, the disappearance of blue green algae and the thriving of the halotolerant green alga Dunaliella salina.

2

Response of periphyton community to salinity gradient in tropical estuary, Niger Delta

100%

Chindah A. C.

Polish Journal of Ecology

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2004

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tom 52

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nr 1

EN

Studies on periphyton of Crinium plants were conducted in the estuary (New Calabar River) of the Niger Delta at 4 different locations during the two major seasons (rainy and dry season). Periphyton samples were collected from an area (of 2 cm by 2 cm) in 3 sets of 3 replicates for biomasses (AFDW-ash free dry weight and chlorophyll a) and for numerical abundance. Physicochemical parameters such as temperature, pH, conductivity, hardness and salinity were also collected from the respective stations. Temperature was considerably uniform but conductivity, hardness and salinity showed increasing graduation in concentration down stream. A total of 110 periphyton species were recorded with diatoms constituting 54% of the occurring species followed by Euglenophyta (21%), Chlorophyta (17%), Cyanophyceae (6%) and Rhodophyta (1.8%). There were strong similarities in the values obtained for species richness, periphyton abundance, and chlorophyll a, AFDW (ash free dry weight) for wet and dry season indicating no seasonal influence. However, the periphyton abundance, chlorophyll a and ash free dry weight distribution suggested strongly influence by the salinity gradient. The values for periphyton abundance ranged from 2621 (±168.5) to 3452.8 (±715.9) indiv. cm⁻². In addition, the combined mean values for chlorophyll a, and ash free dry weight in the system were 8.443 ± 2.51 mg cm⁻² and 0.32 ± 0.07 g cm⁻², respectively.

3

Effect of physicochemical parameters on zooplankton in the brackish, coastal Vistula Lagoon

84%

Paturej E. , Gutkowska A. , Koszalka J. , Bowszys M.

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nr 1

EN

This paper analyzes whether physicochemical properties significantly influence the occurrence of zooplankton in a brackish reservoir. The studies were carried out on the Vistula Lagoon in August and September from 2006 to 2009 at 32 research sites. The environmental conditions in the Vistula Lagoon varied widely. At the time of the investigation, 17 species of rotifers, six species of Cladocera, and ten species of Copepoda were noted, and the total density of plankton fauna ranged from 145 to 765 ind. dm3. Statistical analysis demonstrated a significant correlation between the occurrence of some zooplankton species and certain environmental parameters, whereas the sampling sites were grouped according to study years. The zooplankton systems recorded at the research sites in 2006 constitute the most disparate group. Thus, it can be concluded that physicochemical properties might significantly impact both individual species (depending on their environmental demands) and entire zooplankton clusters.

4

Evaluation of the carbon sequestration capacity of arid mangroves along nutrient availability and salinity gradients along the Red Sea coastline of Saudi Arabia

84%

Shaltout K. H. , Ahmed M. T. , Alrumman S. A. , Ahmed D. A. , Eid E. M.

Oceanologia

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2020

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tom 62

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nr 1

5

The relationship between dissolved carbohydrates and carbohydrate-degrading enzymes in the salinity gradient of the Pomeranian Bight (Southern Baltic)

84%

Nausch M. , Kerstan E.

Oceanologia

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2003

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tom 45

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nr 3

EN

From 1994 to 1996 changes in the concentrations of dissolved mono- (MCHO) and total dissolved polysaccharides (TCHO) as well as the activities of carbohydratedegrading enzymes (α- and β-glucosidase, glucosaminidase) were investigated during mixing of water from the River Odra and the open Pomeranian Bight. This study addresses the question of whether their distribution was a result of physical dilution alone or if biological interactions were detectable. Within the salinity gradient, ranging from 1.9 to 7.8 PSU, TCHO declined from 13.2 μmol l−1 near the Świna mouth to 2.8 μmol l−1 after mixing. Concentrations of MCHO decreased from 3.4 μmol l−1 to 1.1 μmol l−1 but its distribution pattern varied more between summer and autumn than that of TCHO. The hydrolysis rate (Hr) by glucosidase and glucosaminidase activities was reduced from 13.9% h−1 to 0.3% h−1 and 9.9% h−1 to 0.2% h−1, respectively, and correlated with the uptake rate of glucose (To) by bacteria. In summer, the To/Hr ratio increased from about 1.2 to 29.4, mainly because of stronger decreases in Hr than in To. It was shown that the relationship between enzymatic release and uptake of carbohydrates influences the concentration of dissolved carbohydrates within the salinity gradient. Most probably, the decrease in carbohydrate-degrading enzymes is the result of reduced substrate stimulation and the lower number of particle-associated bacteria.

6

Assesment of halophytic vegetation to improve livestock-feeding resources on saline desert renglands

67%

Aralova D. , Shuyskaya E. , Khujanazarov T. , Toderich K. , Taha F. , Oishi S. , Voronin P. , Black C.

Roczniki Geomatyki

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2009

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tom T. 7, z. 5

7-15

EN

The present study aims to describe the spatial distribution of desert plant communities along salinity gradient and explores the relationship between different ecological types of halophytic vegetation and soil properties. Modern techniques to predict trends of neo-halophylization process from soil and plant cover data were tested. The regression analysis was applied to investigate correlation between remote sensing data, Na+ ion content and EC values calculated from field data in order to predict soil salinity and vegetation changes.

PL

W badaniach zależności pomiędzy przestrzennym rozmieszczeniem roślinności na pustyni Kuzył-Kum a zmianami biofizycznej i chemicznej charakterystyki gleby wykorzystano geobotaniczny opis zespołów roślinnych oraz mapy roślinności uwzględniające gradient zasolenia. Wyniki tych badań wskazują, że zasolenie gleby, wilgotność i zawartość jonów sodu są głównymi czynnikami odpowiedzialnymi za zmiany roślinności. Bogactwo roślinności, różnorodność gatunków botanicznych, biomasa roślin są dobrze zintegrowane z zasoleniem gleby liczonej dla nagromadzenia jonów sodu. W sezonie zimowo-wiosennym stwierdzono spadek zasolenia gleby oraz koncentrację innych jonów, co przypisuje się efektowi rozcieńczenia przez wodę ze śniegu i deszczu. Zawartość jonów mineralnych, mierzona za pomocą EM38 oraz elektrokonduktometru (EC), w połączeniu z opisem geobotanicznym dominujących zespołów roślinnych, posłużyły jako wskaźniki biomasy (ilość żywej tkanki roślinnej) i są używane razem z liczbą dni wegetacji z temperaturą wyższą od zera (GDD>0) lub dni od zasadzenia do dokładnie przewidywanego terminu zbiorów. Wykonany w badaniach pomiar przewodności elektrycznej (EM38) wskazuje na dodatnią korelację z zawartością jonu Na+ w profilach gleby i może być wykorzystywany dla szybkiego testowania rozkładu przestrzennego zasolenia gleby, a w efekcie zmian pokrywy roślinnej w środowisku słonej pustyni. Większość gatunków słonolubnych wykazywała regularne rozmieszczenie. Ich obfitość wahała się znacznie w zależności od gradientu zasolenia, a w mniejszym stopniu od wskaźnika suchości klimatu. W wyniku rosnącego zasolenia gleby zaobserwowano zastępowanie zespołów drzew i krzaków głównie trawiastymi roślinami słonolubnymi. Struktura gatunków zmieniła się również w wyniku wypasu bydła . pojawiły się w pokrywie roślinnej egzotyczne, mniej smaczne, rośliny słonolubne. Rekultywacji i zwiększeniu produktywności terenów o glebach podatnych na zasolenie sprzyjałoby zagospodarowanie i włączenie roślin słonolubnych, wartościowych jako pasza, do systemu rolnictwa biosolnego. Problem żywienia bydła można by rozwiązać wprowadzając uprawę na pasze trawiastych roślin słonolubnych pomiędzy plantacjami drzew i krzewów tolerujących sól. Tym samym wzrosłyby dochody rolników.

7

Phytoplankton assemblage of a solar saltern in Port Fouad, Egypt

67%

Madkour F. F. , Gaballah M. M.

Oceanologia

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2012

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tom 54

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nr 4