Qualitative and quantitative study of algae in three drinking water plants supply springs in Sulaymaniyah province - Kurdistan region of Iraq

In this study, three drinking water treatment plant supply springs were selected within different sites in Sulaymaniyah province-Kurdistan region of Iraq. Samples were collected over period of eight months from May to the end of December 2015. Five stations were selected, Stations 1, 2 and 3 were located at Bestan Sowr drinking water project in Sharazur district, station 4 was located at Saray Subhan Agha drinking water project in Said sadiq district and station 5 was located at Khurmal drinking water project in Khurmal district within Halabja district. The study involved a qualitative (identification) and quantitative (Density and Total count) study of phytoplankton in water for selected stations. A total of 155 algal species were identified belong to 9 classes in all studied stations, 80 species belonged to Bacillariophyceae (diatoms), 35 species to chlorophyceae, 30 species to Cyanophyceae, 3 species to Euglenophyceae, 2 species for each of Crptophyceae and Pyrophyceae and 1 species for each of Chrysophyceae, Dinophyceae and Xanthophyceae. Diatoms were dominated (according to the total count of taxa) over all other phytoplankton in all sites, Chlorophyceae formed the second most algal group at the selected sites and Cyanophyceae formed the third most algal group of phytoplankton at the selected sites. The results of phytoplankton quantitative study in the studying stations recorded the highest total density of phytoplankton during the study period was at Station1 (18377.


Introduction
Algae most commonly occur in water, be it fresh water, marine, or brackish.However, they can also be found in almost every other environment on earth, from the algae growing in the snow of some American mountains to algae living in lichen associations on bare rocks, to unicellular algae in desert soils, to algae living in hot springs.In most habitats they function as the primary producers in the food chain, producing organic material from sun light, carbon dioxide, and water [1].Algae are made up of two broad groups.Macrophytes are large and are often attached to rocks and other surfaces and can be seen with the unaided eye.Phytoplankton, which are suspended in the water column, usually require a microscope for individual organisms to be seen, unless present in large quantities [2].Microalgae are unicellular micro-organisms.
Microalgae are categorized as prokaryotes and eukaryotes.Organelles are the major difference between prokaryotes and eukaryotes.Prokaryotes do not possess chloroplast, mitochondria and nuclei but they contain chlorophyll a and high protein contents.Microalgae are further divided into different groups based on their taxonomy, including blue-green, green, yellow-green, red, brown, and golden algae.There are more than 50,000 species of microalgae [3].

Studying Area
Five stations were selected for the study, all outside the city of Sulaymaniyah center.Three of these in a Bestan Sowr drinking water project within Sharazur district, the fourth station lie in Saray Subhan Agha drinking water project in Said Sadiq district, and the fifth station in Khurmal drinking water project (Figure 1).

Studying stations First station:
The sample of water in this station was taken from the beginning of the assembly basin at Bestan Sowr drinking water project.

Second station:
The sample of water in this station was taken from the mid of the assembly basin at Bestan Sowr drinking water project.

Third station:
The sample of water in this station was taken from the end of the assembly basin at Bestan Sowr drinking water project.

Forth station:
The sample of water in this station was taken from the assembly basin at Saray Subhan Agha drinking water project.

Fifth station:
The sample of water in this station was taken from the assembly basin at khurmal drinking water project.

Qualitative analysis (Algal identification)
Non-diatomic algae were identified by preparing slides and examined under 40 xs by using a compound microscope depending on the following references which were used for identification of nondiatomic algae [4-7.While diatoms were identified after dissolving the organic matter by using nitric acid and examined under 100 xs depending on [8] and [9].

Quantitative analysis
Total number count of phytoplankton was performed by using the sedimentation method [10] (Figure 2).One liter of each sample taken was put in graduated cylinder (1000ml), samples were preserved by adding drops of Lugol's solution and left in stand place, after seven days, 900 ml were sucked by siphon method.The rest was transported to another cylinder (100 ml) and left at the same method to seven days, after that 90 ml was withdrawn and the rest (10ml) put in covered glass container and adding two drops of Lugol's solution.

Figure 2: Sedimentation Method
Non diatomic phytoplankton was measured by using haemocytometer, 1ml of concentrate was put on the slide chamber and covered with cover slide then non diatoms identified and enumerated under microscope, the results expressed as individual per Liter (ind/l).For diatomic algae, a clean slide was left on a hot plate at 75-80°C and a 1ml of the preserved concentrated sample was put in the middle of the slide and dried, then a drop of concentrated Nitric acid was put on the dried drop and after evaporation of the acid drop, Canada Balsam was placed on a cover slide and put on the dried sample and pressed to remove any air bubbles [10].The calculation was done by the equations have been mentioned by [11].Lugol's solution prepared by dissolving 10g pure iodine in distilled water, then 20g potassium iodide was added then the volume completed to 200 ml distilled water containing 20 ml glacial acetic acid and kept in a dark glass bottle [12].

Statistical Analysis
The results of this study were analyzed statistically using analysis of variance test (F test), and has been compared the means by a polynomial Duncan test in level of 0.05.

Qualitative study of phytoplankton
A total of 155 algal taxa (Appendix 1) were identified belong to 9 classes in all studied stations, 80 taxa belonged to Bacillariophyceae (diatoms), 35 taxa to chlorophyceae, 30 taxa to Cyanophyceae, 3 taxa to Euglenophyceae, 2 taxa for each of Crptophyceae and Pyrophyceae and 1 taxa for each of Chrysophyceae, Dinophyceae and Xanthophyceae.As noted in the appendces 2, 3, 4, 5, and 6, and Figures 3, 4, 5, 6 and 7, Diatoms were dominated (according to the total count of taxa) over all other phytoplankton in all sites.Bacillariophyceae or diatom group remained dominant in most stations during winter in the present investigation which could be attributed to the fact that they are able to grow under the condition of weak light and low temperature which are less suitable for other algae and low concentration of nutrients (NO 3 -N and PO 4 -P) in the winter [13].In diatom, the pennales diatom was abundant over the centrals, figures below show the dominance of diatoms in all studied stations.The most abundant species of Bacillariophyceae which identified in all studied stations and most periods of study were (Centrales): Cyclotella ocellata, (Pannales): Achnanthes minutissima, Cocconeis pediculus, Cocconeis placentula var.euglypta, Cymbella microcephala, Fragilaria ulna, Navicula cryptocephala, these species were recorded to be the most dominant species amongst the bacillariophyceae, in addition to the clear dominant for some species of Bacillariophyceae in certain stations such as Navicula riediana was dominant in station 5. Chlorophyceae (35 species) formed the second most algal group at the selected sites, The most abundant species of Chlorophyceae which identified in most studied stations and in most periods of study were: Ankistrodesmus falcatus, Chlorella vulgaris, Oedogonium sp., Pediastrum boryanum, Scenedesmus biguga, Scenedesmus quadricauda.Amongst chlorophyceae, Oedogonium sp. was found to be the most dominant species at all stations, in addition to Desmodesmus itascaensis were dominant in stations 2 and 3, Desmodesmus lunatus in stations 1, 2 and 3, Ulothrix zonata in stations 1 and 4. Cyanophyceae (30 species) formed the third most algal group of phytoplankton at the selected sites, the most abundant species of Cyanophyceae which identified in most studied stations and in most periods of study were: Chroococcus disperses, Oscillatoria limnetica, Oscillatoria tenuis.Amongst Cyanophyceae, Oscillatoria tenuis was found to be the most dominant species at all stations, in addition to Calothrix fusca were dominant in station 4 and Chroococcus turgidus in station 1. Same results were Observed in many research in Iraqi and Kurdistan region such as [14,15,11] in Dukan lake, [16] in Duhok lake, [17,18] in Baghdad, [19,20] in Sarchnar spring and Chaq-Chaq stream in Sulaymaniyah Province.[21] reported that the great similarity between species in the studied sites belonging to the same source of water which provides these sites.The results of phytoplankton quantitative study in the studying stations recorded the highest total density of phytoplankton during the study period was at Station1 (18377.28ind×10 3 /l), followed by (12513.34ind×10 3 /l) at Station 2 and (4779.45ind×10 3 /l) at Station 3. The lowest total density was recorded at Station 5 which was (2834.43 ind×10 3 /l) as shown in Appendix (1) and Figure (8).This variation of phytoplankton density and total count between the sites may be due to the differences of the environmental factors at those sites such as light penetration, temperature, nutrient enrichment, toxic substances, mixing of water, parasites, herbivores and heterotrophic microorganism activities influenced the phytoplankton growth [22] and [23], as well as there are several other factors that may be helped in the formation of these differences in density of phytoplankton between stations 1, 2 and 3 (located in the assembly basin at Bestan Sowr drinking water project) Which ones the third station is located under the shade of trees, consequently, the place of sampling for third station exposure to direct sunlight slightly compared with a first and second station, in addition to the third station exposed to concentrations of chlorine which is pumped into the assembly basin for the purpose of reducing the concentration of algae as one of the methods used by those working in the project, as well as the lack of depth of the water in the first station which allowed to sunlight from reaching the bottom of the basin, all of these reasons could explain this difference in the density of phytoplankton in the studying stations.

Figure 8: Total density of phytoplankton in studied stations
Generally and regardless of the type of algae the results of total Count of microalgae at all stations ranged between 5913×10 3 cell/l and 29×10 3 cell/l.The highest number of total Count of phytoplankton 5913×10 3 cell/l was recorded at station 1 during September and the lowest number 29×10 3 cell/l was recorded at stations 5 during December (Figure 9).

Figure 9: Total Count of phytoplankton in studied stations
As previously noted, and depending on the total count of phytoplankton, the Bacillariophyta (Diatoms) were dominated over all other phytoplankton in all stations, followed by Chlorophyceae (Green algae) and Cyanophyceae (Blue green algae) followed by other types of algae the number of their cells a few (as shown in the appendces 2, 3, 4, 5, and 6(.The first station has recorded total count of phytoplankton (9205.1×10 3 , 1120.1 ×10 3 and 432.1×10 3 ) for Bacillariophyceae, Chlorophyceae and Cyanophyceae Respectively, station 2 has recorded total count of phytoplankton (6138.3×10 3 , 907.1×10 3 and 204.6×10 3 ) for Bacillariophyceae, Chlorophyceae and Cyanophyceae Respectively, station 3 has recorded total count of phytoplankton (1871.3×10 3 , 672.3×10 3 and 219.3×10 3 ) for Bacillariophyceae, Chlorophyceae and Cyanophyceae Respectively, station 4 has recorded total count of phytoplankton (1318.6×10 3 , 360.9×10 3 and 264.4×10 3 ) for Bacillariophyceae, Chlorophyceae and Cyanophyceae Respectively, station 5 has recorded total count of phytoplankton (884.5×10 3 , 667.5×10 3 and 180.5×10 3 ) for Bacillariophyceae, Chlorophyceae and Cyanophyceae Respectively.Figure (9) showed that the total count of phytoplankton recorded a rise in the number of phytoplankton during the summer, especially in the months of August and September in most of the stations, as well as the lower numbers of phytoplankton showed at the end of summer and the beginning of autumn and the decline of their numbers during the winter these results agree with many of the research and studies on the phytoplankton in freshwater, however, mainly seasonal changes regulated pattern of phytoplankton growth.Studies reported that the summer is the most suitable season for the growth of phytoplankton in freshwater bodies because of long duration of sunshine period, increased salinity and trophotropic activities and therefore increased phosphorus and nitrate concentration [24].Conversely, in late summer, autumn and winter the production of phytoplankton reduced because of heavy rainfall, high turbidity, reduced salinity, temperature, overcast skies and low nutrient concentration along with consumption of phytoplankton by zooplankton [25].This variation of phytoplankton total count between the sites may be due to the differences of the environmental factors at those sites, which related to the geological formation in this sites [14].Phytoplankton distribution majorly forced by factors such as seasonal fluctuations in water body.Factors such as seasonality, period of sunshine, wind patterns, depth of water, temperature, pH, turbidity, dissolved oxygen, nutrient enrichment like dissolved chloride, phosphate Nitrogen and organic carbon ultimately influenced the occurance phytoplankton in the freshwater body [26].Total quantity of phytoplankton was determined as a good indicator to know the water quality and types of nutrients which present in it [26].This study revealed that the water quality parameters such as temperature, pH, nitrate and phosphate play a very important role in altering the Quantity phytoplankton.12.9 12.9 Chroococcus disperses 12.9 12.9 Chroococcus turgidus (Kützing) Nägeli 12.9 12.9 25.8 Lyngbya limnetica Lemm.

Figure 1 :
Figure 1: Location of the Studied Sites (Google earth, 2015)