Study algae and fungi interaction in some artificial open sand mine ponds in Kalak sub district-Duhok , Iraq .

Phycology, mycology and physicochemical parameters of some artificial open sand mine ponds in Kalak sub district-DuhokIraq were investigated, for a period of six months from July to December-2015. Water samples were collected monthly basis and analyzed for measuring of water temperature, turbidity, pH, electrical conductivity, nitrate, nitrite, ammonium, orthophosphate, dissolved oxygen and biochemical oxygen demand. Concerning algal communities, the results showed that the sixty taxa were identified in samples collected during the study period. They belong to classes Cyanophyceae (18 taxa) with percentage composition of 30%, Chlorophyceae (20 taxa) with percentage composition of 33.3%, Euglenophyceae (2 taxa) with percentage composition of 3.4%and Bacillariophyceae (20 taxa) with percentage composition of 33.3%.According to Shannon-Weiner index, species diversity varied from (2.053to 3.895bits/ind), in pond 3 and in July had the highest diversity were recorded. Concerning to Jaccard similarity index, the highest percentage of similarity to algal community observed between site2 and site 4 reached to 32%. The diatoms were the most noticeable algae in all ponds which represented by Cyclotella, Navicula, Syndra and Cymbella with respect to the frequency of occurrence and number of individuals in all ponds. The diatoms showed their best growths through this study. The dominant of Chlorophyta and Cyanophyta followed by Study algae and fungi interaction in some artificial open sand mine Ponds in kalak sub districtduhok, iraq. Yahya A. Shekha, Janan J. Toma and Hero M. Ismael 110 Vol: 13 No:2 , April 2017 DOI: http://dx.doi.org/10.24237/djps.1302.239C P-ISSN: 2222-8373 E-ISSN: 2518-9255 diatoms. The dominate species among non-diatoms were, Oscillatoria, Pedistrum, Oedogonium, Cladophoraand Cosmarium. Out of 23 fungal species belongs to 17 fungal genera were isolated. Trichoderma sp. was most frequent species, Aspergillus spp. followed by Penicillium spp. and Eurotium spp.


Introduction
During few decades, gravel-and sand-pit ponds have been created as a consequence of quarrying, especially in river flood plains (1).Most of these ponds are isolated water-bodies that receive mainly fed by groundwater and in wet months from rainfall (2).Due to their location in the riverine transitional zones they are often connected to rivers or channels, which greatly affected their hydrology and community structures (3).Algae represent the important nutritive base and have a significant effect on the biological productivity of a water body and on the properties of water quality such as color, smell, taste, dissolved oxygen, turbidity (4 and 5).Algae particularly diatoms are generally accepted as one of the most suitable bio-indicators of aquatic ecosystem for water quality monitoring and organic pollution (6).Specific algae grows in specific environments and therefore, their distribution pattern, periodicity and productivity are different vary from water to water body.Surveys of phytoplankton species composition in relation to habitat conditions are the baselines for the understanding of ecosystem functioning (7).Aquatic fungi play an important role in the cycling of carbon, nutrients and energy fluxes.The degradation of litter plant and animal residues is carried out by a number of poorly known groups within the phyla Chytridiomycota, yeasts, and hyphomycete lineages of Ascomycetes (8).Sediment aquatic fungi represent a significant component of the benthic microbial biomass in reservoirs, and these organisms are a vital biological force in regulating water quality through decomposition of organically bound C and N deposited on the bottom (9).Due to their valuable services in the ecosystem, changes in fungal assemblages could provide insight into the physicochemical assessment of river water quality and ecosystem health (10).The increased variations of the physical and chemical factors which in turn disturbs the biology of the water body and results in ecological imbalance and act

Description of the study area
Khabat sub district is far about 37 km from west of Erbil city located on the main road between Erbil and Mosul city.Khabat sub district located on the Great Zab River, the area is characterized by agricultural, tourism and production of raw construction material from many sand mine established along Greater Zab River banks.The study has been carried out in five neighboring ponds created as a result of sand mining with hydraulic dredging, approximately (150-200 m apart) from the main course of the Greater Zab River near Gahatli village (Figure 1).The depth of these excavation open sand mine pits ranged between 5-12 meters.All ponds have no inlet or outlet connections to the river, and are mainly fed by groundwater from the same source (from river and rainfall in wet months).The selected ponds were at the end of the excavation phase, when these artificial ponds become hydrologically mature, in order to known the colonization patterns during the excavation period.isolation of fungi from soil sediment made by dilution method, a dilution of 10 -3 was chosen for the estimation of the fungal total count.After observing the growth under a stereoscopic binocular microscope it was cultured on SDA supplemented with chloramphenicol (50 mg/l) (21).

Results and Discussion
Physico-chemical properties: Water temperature values of the studied sites ranged from 19 ºC to 24ºC recorded in ponds 1 and 3 respectively (Table 1).This variation in temperature may be attributed to nature of the area and the time of samples collection, this result was similar to studies done by (14 and 15).In this survey, the turbidity value ranged from 1.0 to 36.0 NTU, this variation may be due to erosion, algal growth or other anthropogenic activities around ponds. ( 22) indicated that the effects is directly related to extraction and to changes in geomorphology include increased sedimentation, turbidity, and bank full widths.In general this result comes in accordance with (23).Generally, pH value of the most studied ponds is similar and it ranged from 7.2-7.5, this return to the geology formation and the catchment area of the ponds which characterized by alkaline status (24).This found to be true for artificial open sand mine ponds in Kalak subdistrict in the present work.Similar observations observed by (13 and 25).Conductivity levels of the studied ponds water samples ranged from 347.8 to 592.4 μS.cm -1 .The variations in EC values of the water depend on pH, temperature, geological origin, and the content of the ionic salts such as calcium, magnesium, sulfur, and other ions (16).
Table (1 Dissolved oxygen in surface pond samples was high during the entire sampling period in Kalak subdistrict was ranged from(4.0-6.6mg.l - ), this fluctuation might be attributed to several reasons; the area of clear water exposed to the air, the circulation of water within system, and the amount of oxygen generated and used by the organism present (28).Generally, pond surface water was containing low organic matter which was shown from low values of BOD5 2.3-8.9 mg.l -1 recorded during the studied period, this may due to nature and concentration of the organic substances in the water to be broken down, nature, number and adaptation of the microorganisms, the nature and quantity of nutrients for the microorganisms, temperature, and the effect of light (27), similar results by (13, 14 and 15) was mentioned.

Phycological composition:
The algae play an important role in aquatic ecosystems, as the primary producers, thus they are the first link in the food chain, and often cause nuisance condition (27).2).
According to the present results, it seems that diatoms were more abundant than other groups.
Cyclotella, Fragilaria and Syndra were more significant than other diatoms and algae since they were recorded in communities with larger populations (Table 3).These findings may Cosmarium appeared in the ponds only in summer months.Euglena has been the most important genus in Euglenophyta as being represented with 1 taxa.The appearance in very low number and in the sites during this survey indicate that the water is poorest with organic matter content (33).Oscillatoria was the richest blue-green algal genus in species composition.The occurrence of the blue-green algae, especially Merismopedia, in summer and autumn was noticeable, thus supporting the Round view's that the blue-green algae Merismopedia, Anabaena, Lyngbya and Oscillatoria grow better and are more common especially in summer months (34).activities (Tourist and waste disposal) as bacterial population was estimated in higher concentration from water samples collected from the bank of the ponds (35).Surface waters tend to contain larger amounts of organic matter, which both provide nutrients and a substrate for fungal growth.Differences in acidity and calcium content may also account for some of the variation (36).This result is agreement with that found by (37 and 38) who isolated numbers of yeasts and filamentous fungi in pond waters as Aspergillus niger, Trichoderma sp., Acremonium sp., A. tamarii and Rhizpous sp., except for November, when adverse conditions of undetermined nature reduced the fungal populations.(39) reported that the occurrence of Mucor sp. in earthen ponds could be attributed to the fact that the earthen ponds was a more conducive environment for their growth and proliferation due to the presence of soil and plants in the earthen ponds.The waters of streams, ponds, lakes, and estuaries always contain spores of many kinds of fungi.However, total fungal count was high during October while the lowest rate of isolated fungi was at July (7.6 CFU.ml -1 ), this may be related to human activities and waste disposal around ponds bank.respectively.( 40) elucidate that Sediments serve as seedbank for resting spores of not only aquatic fungi but also of various terrestrial species.In the upper sediment layers, the response to antibiotic addition suggested a possible heterotrophic fungal activity in this habitat.While the isolated yeast from the present study were Rhodotorula glutinis followed by Cryptococcus albidus and Candida albicans which were 23, 4 and 2 x 10 3 CFU/gm. of sediment respectively.These results comes with that found by (41, 42, 43 and 44) who reported that the dominant isolated filamentous fungi in raw water were Aspergillus spp., followed by Penicillium spp.and Cladosporium spp., yeasts were Cryptococcus curvatus, Candida, Rhodotorula mucilaginosa and Sacccharomyces cerevisiae relatively.

Community structure and biodiversity:
Our results show that while some species could tolerate and thrive at certain levels of some physicochemical parameters, others showed sensitivity to the same parameters at these levels.
The environmental requirements of different species differ, hence defining how they respond to variations in these factors.Our study has shown that the occurrence and abundance of green algae species in these ponds are closely linked to their physicochemical characteristics.In addition, most parameters analyzed showed specific temporary and/or spatial variation.
Monthly variations of phytoplankton showed the maximum density in summer months which indicates that the temperature of these months played an important role in increasing the population of phytoplankton.Similar observations were made by (45) and the dominance of various phytoplankton species was less in monsoon months.This may be due to dilution of  7).Statements that of (47) seem to confirm the present results, however, as stated by same authors, on a seasonal basis, particularly in temperate waters, diversity tends to increase in hot months and below in cold months.On the other hand as outlined by (48), in perturbed waters by man activities such as use of fertilizers, rapid change in species composition which in turn shifts diversity values would be expected.On the other hand, fungal diversity in sediment was higher than in water sample in all studied ponds.High species occurrence, isolation and diversity index (H`) and counting in sediments than in water, may be related to availability of organic detritus on sediments that supply a good sources of food and habitat for these decomposers (49).It seems quite clear that the availability of organic matter, pH and water temperature play important role in the existence and propagation of aquatic fungi in lakes (50).Same phenomenon was observed by (42) during their study on Duhok impoundment.Ponds 1 and 3 showed more species diversity compare to other ponds, this may return to nature of ponds and physico-chemical characteristics.The similarity index provides a quantitatively based measurement for comparing two populations.
The Jaccard similarity index often used to measure the species-diversity for the optimum size for natural protection (51).There are only slight differences as concerning the floristic affinities among the communities of the ponds.The values of Jaccard similarity index exhibit low values and uniformity: the maximum 32% found between ponds 2 and 4, minimum 9% being the joining level of pond 1 to the main aggregate (Table 8).While, for fungal composition, maximum similarity 70% and 60% found between pond 3 and other ponds 1 and 5.This pattern is due to the location in chain of the ponds, namely pond 2 and 4 are the nearest ones receiving first the river water, and pond 1 is the most remote one alimented with the water after it flows through all other ponds.In ponds 2 and 4 occur most of the rheophilic elements detected for this wetland, by the contrary pond I is characterized by the occurrence of numerous typically lentic species., this variation of similarity between sites may be related to the pH, temperature, nutrient and other factors like climate, soil of the studied area that play important role to increase and decrease the diversity of each site during this survey (48).

Figure ( 1 )
Figure (1) Maps Shows A: Northern part of Iraq, B: Sampling artificial sand mine ponds on Greater Zab River bank (From Google earth).

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Some water quality characteristics for sand mine ponds, data represented as minimum and maximum values.No:2 , April 2017 DOI: http://dx.doi.org/10.24237/djps.1302.239CP-ISSN: 2222-8373 E-ISSN: 2518-9255Surface water samples of studied area showed nitrate range between (1-3.29 mg.l -1 ).This variation in nitrate levels depends on several factors such as the fertility of soil in the drainage basin, domestic sewage, mixing and rainfall(26).Concentration of ammonium in this survey varied from( 5.6-9.8µg/L),this depending upon the quantity of oxygen, pH and water temperature or decomposition of organic matter and urea by microbial action in addition to other factors such as fertilizer and rainfall(27).The variation of phosphate concentration during this study may be connected to phytoplankton activities, and allochthonous inputs(27).Both nitrogen (NO3 and NH4) and phosphate content is very important for algal growth, the variation of these nutrients is coincided by algal fluctuation.
(28 and 29) stated that the algae are considered to be excellent indicators of water quality, and certain species are capable of indicating water conditions.During the present investigations, 60 species of algae were identified and classified into four following classes, of which 22 were Bacillariophyceae, 20 to Chlorophyceae, 20 belonging to Cyanophyceae and 2 to Euglenophyceae (Table

Yahya A. Shekha ,
Janan J. Toma and Hero M. Ismael 116 Vol: 13 No:2 , April 2017 DOI: http://dx.doi.org/10.24237/djps.1302.239CP-ISSN: 2222-8373 E-ISSN: 2518-9255indicate that, these diatoms have a larger ecological tolerance against the possible changes of conditions in the ponds across the year.The best growth period for diatoms in sand mine ponds was autumn months, while lower cell numbers was recorded during summer months (Table4).Water temperature and light have been reported as the most effective factors on seasonal developments of algae; however, other factors also affected the number of algae(30).The role of zooplankton in shaping phytoplankton communities is well known, especially cladocerans (the active ingested filter feeder on phytoplankton and other microorganisms).The possibilities of filtering activity of herbivorous zooplankton had a major impact on phytoplankton community structure(31 and 32).Chlorophyta and Cyanophyta were other important algal groups in the ponds.Although green algae have been recorded in samples in all studied months, in which they were richer in species composition in summer months when diatoms were represented with less species.Pedistrum (3 taxa) and Scenedesmus (2 taxa) were the richest genera in terms of species number.Although Closterium and Cosmarium were represented with only one species, they were present in the ponds almost throughout the study period.

Yahya A. Shekha ,
Janan J. Toma and Hero M. Ismael 125 Vol: 13 No:2 , April 2017 DOI: http://dx.doi.org/10.24237/djps.1302.239CP-ISSN: 2222-8373 E-ISSN: 2518-9255 water on account of rain as well as greater water movement and flooding due to heavy rain.Generally, Shannon's values were reached three or more during entire sampling period.This probably due to, that phytoplankton communities in sand mine ponds, which were consist of a diverse assemblages of species influenced by a wide range of environmental parameters, such as; temperature, light, and nutrients(46).As demonstrated by(47 and 48), predominance of one or two species results in low diversity, while high values occur when populations of several species each from moderate proportions of the total counts.The higher values in Shannon's index were recorded during July 2015, while the lower ones were calculated during September2015 (Table Yahya A. Shekha, Janan J. Toma and Hero M. Ismael 126 Vol: 13 No:2 , April 2017 DOI: http://dx.doi.org/10.24237/djps.1302.239CP-ISSN: 2222-8373 E-ISSN: 2518-9255