Identification of Pollution Level of Coastal Waters in the Lagoons of Narta and Oricum, Through the Phisical-Chemical and Bacteriological Indicators
Total Page:16
File Type:pdf, Size:1020Kb
Identification of Pollution Level of Coastal Waters in the Lagoons of Narta and Oricum, Through the Phisical-Chemical and Bacteriological Indicators Assoc. Prof. Muharrem Shehu, Assoc. Prof. Lauresha Shabani University “I. Qemali” Vlore, Albania Abstract This research represents data about Narta and Oricum lagoon. Narta lagoon is situated in the south side of Vjosa river overflowing in Adriatik sea and Oricum lagoon is the next one,situated in the south side of Vlora bay.They represent very important habitats because of their turistical value and the use of them for fishing.Therefore it is important toknow the quality of coastal waters in order to ensure if they are safe to bathe,otherwise to evaluate the level of pollution: The microbiological examination of water samples is made to determinante the total charge of aerob mesofilic bacteria and the quantity of thermo-tolerant coliforms as indicator of fecal pollution.This analyse is made by the multiple-tube fermentation method and the results are evaluatet as most probable number (MPN).As well as these characteristics the article contains data about the physic-chemical parameters of these waters such as ,pH and temperature values, the electric conduction, the content of some main inorganic ions,the quantity of oxygen soluble ect.The samples for analyses are collected fromfour stations by each lagoon in the months of autumn, and spring-summer season.According these data there are areas in these habitats where the pollution is evident.We think that the state and bad management of urban wasterwater system is the main cause of environment pollution. Key words: lagoon, coastal water, pollution, coliforms bacteria, physical-chemical parameters. INTRODUCTION The district of Vlora, one of the largest in Albania, is situated in the North-West coast of the country. The city of Vlora covers an area of 29.5 sq km, stretching 19 km in length (North-South) and 16 km in width (East-West). Its altitude is 6 metres above sea level, and the mean temperature 9-10ºC. Geologically, it is a combination of sinclines and anticlines, whereas from the physic-geographic viewpoint, the District of Vlora is situated in the Southern Mountainous Region. The relief, in most parts of the region, consists of limestone formations. THE LAGOON OF NARTA The Lagoon of Narta is situated in the area of Vlore- Narta Myzeqe, south ot the Vjosa delta, from the mouth of the River Vjosa to the cape of Triport. It is dominated by an alluvial plain lying along the low sandy beach. The area, larger than the lagoon itself, is a complex of different types of natural environments, ranging from the sand dunes close to the mouth of the River Vjosa and the Mediterranean pines woods (Pishporo, Vlora), to ancient riverbeds and small shallows along the shore, from the saltpits and salty wastelands to the arable lands east of the area. The lagoon water covers an area of 42 sq km, of which 14 sq km is used by the saltpits of Skrofotina. Its depth varies between 0.70 m and 1.50 m. The lagoon is connected to the sea through two artificial cannals, the north and south ones. Owing to a low level of interchange between the lagoon water and the Adriatic Sea, the small depth, and high level of evaporation, the total area of the lagoon dimineshes to 30% Orikum during the dry season. The Lagoon of Narta is one of the lagoons in Albania which is undergoing rapid degradation mainly because of the very low amount of salt and/or fresh water. Hence, the BALWOIS 2010 - Ohrid, Republic of Macedonia - 25, 29 May 2010 1 lagoon is subject to frequent dystrophy crises. The most common types of macro-zoobento (living things at a general level) are the edule Cardium bivalves and crustaceans such as crabs. The ictio-fauna is highly varied, sheltering an interesting avi-faune, particularly during the winter. The woods in this area were only planted about 30-40 years ago. The dominant types are the common pine and white pine, whereas the lower level of the woods consists of evergreen shrubs. Weeds are very little represented. Spiky vegetation is present along the north and north-east shores of the lagoon, as well as the boundary to the mouth of the river Viosa. During the summer the area covers in spiky vegetation and evergreen shrubs. The sand dunes of the are are typical of the Adriatic coast dunes. At times they reach the hight of 4-5 metres and are dominated by the sand amophyla, which shape this vegetation. The Lagoon of Narta has today a high degree of athrophy. The amount of oxygen in the water falls greatly during the summer, which causes a rapid athrophying of the lagoon. If the level of communication with the sea or the fresh waters remains low, then the dystrophy crises will become more frequent in the future. The sewage disposal into the south-eastern part of the lagoon is another source of organic pollution. Seaweed mixes (Ruppietum circhosae, Zosteretum noltii) cover considerable areas of the lagoon bottom. The main species, making up the so-called underwater pastures of the Lagoon of Narta, are Zostera noltii dhe Ruppia cirrhosa, which cover up to 30-40% of the muddy lagoon bed. Both of these species, alongside with the echological groups of accompanying species (mainly algea), represent one of the most important bio-cenoses for the Lagoon of Narta. THE LAGOON OF ORICUM The Lagoon of Oricum occupies the lower part of a gradual inclination lowland situated in the region of Vlora, between the Harbour of Pasha Liman (west) and the Municipality of Oricum (east). It covers an area of 130 ha, whereas the sorrounding lowlands of Dukat cover about 1,000 ha. The area consists of solid sedimentary deposits from the Dukat torrent. The lagoon has a maximum depth of 3 m and is connected to the sea solely by a 50m-long cannal. It is protected by a dam running NE-SW, and a pumping station prevents the fresh waters from pouring into it. South-east of the lagoon is a drained ex- swamp, now a rich sedimentary plot of land. On account of the low level of exchange between its fresh water and the seawater, as well as the deviation of the torrent that used to pour into it (15 years ago), the whole echosystem has suffered severe changes relating the water regime. The original forest of the muddy field has almost disappeared. Habitats typical of saltwater have replaced the previus types of habitats and vegetation of fresh water-and-saltwater. The lagoon is rich in Cladophora sp. and fytoplanctons, consisting mainly of diatomes (Chaetoceros, Cyclotella, etc.) and peridines molluscs (Prorocentrum). Deep water living things include crabs (Carcinus aestuarii), molluscs (Cerithium vulgatum), (Murex trunculus), (Muricopsis inermis), (Bulla striata), (Venerupis pullastra), and shellfish (Cardium edule), (C. glaucum). A tendency of a persistent growth of the crab population has been perceived in the past few years in the lagoon, which, together with the change in the community of the algea, can be interpreted as an indication of a displacement of the whole ecosystem towards atrophying. Cane proliferates along the west side of the lagoon. This kind of habitat is helped by the freh water pouring from a few small springs, as well as an irrigation cannal at this part of the lagoon. Evergreen shrubs grow on its south- southwest boundaries. The bay is very convenient for migrating birds. Fishing and fish farming in the lagoon are not very important. The previous biological values of this area have diminished drastically on account of the construction of irrigation works. BALWOIS 2010 - Ohrid, Republic of Macedonia - 25, 29 May 2010 2 RESEARCH OUTCOMES The lagoon waters have been monitored in compliance with chemical-biological monitoring schemes, analysing a considerable number of specimens at fixed stations of specimen treating. The micro-organisms indicative of faecal pollution were determined in these specimens, as follows: a- faecal coliforms (CF); b- total coliforms (TF); c- other mesofylle bacteria. However, we think that the number of specimen treating stations for coastal waters should be bigger; because of the time at our disposal, the number of such stations in the study has not been as big as we think it could have been more appropriate. Specimens have been taken from four stations at the Lagoon of Narta, and three from the Lagoon of Oricum. Narta 1: North-East; Narta 2: East, city sewage disposal; Narta 3: West; Narta 4: Village Zvernec 1. Diagram presentation of specimens Specimen 1 Specimen 2 Specimen 3 Specimen 4 Orikum 1: Pasha Liman; Orikum 2: West, close to military base; Orikum 3: Sea-lagoon canal 2. Diagram presentation of specimen-taking spots at the Oricum Lagoon Speciman 1 Speciman 3 Speciman 2 BALWOIS 2010 - Ohrid, Republic of Macedonia - 25, 29 May 2010 3 Table1. Data on the physico-chemical parametres of specimens Samples according to lagoon Comparative indicators Alkalinity Hardness Dissolved (g CaCO3/l) (mg equival/l) oxygen Alk Medium Total Alk.q Alk.pq FTotal F.q F. pq ( mg/l) Lagoon of Narta Sample 1 (code 1) Base 0,235 0,208 0,027 52,33 51,23 1,1 93.2 Sample 2 (code 2) Base 0,256 0,203 0,053 52,83 50,33 2,5 69.2 Sample 3 (code 3) Base 0,233 0,159 0,074 52,85 49,83 3,02 81.2 Sample 4 (code 4) Base 0,267 0,166 0,101 51,58 48,9 2,68 133.2 Lagoon of Oricum Sample 1 (code O1) Base 0,243 0,193 0,05 52,12 51,37 0,75 117.6 Sample 2 (code O2) Base 0,484 0,45 0,034 39,75 38,75 1,0 140.4 Sample 3 (code O3) Base 0,278 0,187 0,091 51 50,56 0,44 148.4 The locations where specimens one and two were taken have particularly high indicators.