ARJAN DEMIRI3, JERINA KOLITARI1, PETTER VEBENSTAD2, GULIELM KROQI1, LAURA GJYLI5
1 Agricultural University of Tirana/Department of Aquaculture & Fishery, ALBANIA
2 Teknologisk Institutt, Oslo, NORWAY
3 Services mussles & shellfish directory, Sarande , ALBANIA
5 Aleksander Moisi University of Durres, ALBANIA
*Coresponding author Email : firstname.lastname@example.org
Butrinti lagoon is situated in the southern part of Albania. It is the only lagoon connected with the Ionian Sea and due to the specific rocky shore of this sea. The water temperature varies with depth and season. In depth 8-10m it is nearly stable throughout the year, respectively 15-17°C. Eutrophication and depth influences ecology and fisheries of Butrinti Lagoon. Due to the depth of 21m, the water in the lagoon is stratified in different layers according to different gradients of temperature, salinity and chemical compounds.There are some factors that define these critical issues in the lagoon. Recent assessments founded that, in summer there is a risk of hyper-eutrophication, when bacteria breaking down organic matter become hyperactive in the heat and available oxygen in the process. In anaerobic conditions the sediments release hydrogen sulphide, which is highly toxic for flora and fauna and can kill populations beyond the point of possible recovery. Stratification process makes that in the deep layers when thermocline and chemiocline are created, the oxygen is consumed very rapidly and big amount of H2S are present. The water ecosystem equilibrium in the lagoon is very fragile. In our experiment are transferred samples shellfish from Shengjini to Butrinti. The samples are analyzed in the periods December 2012 – March 2013 and August – September 2013. From analyzes had these results: Growth positive rate from samples mussels at December 2012 and march 2013. During the period of summer August –September 2013 the measurements have shown that there has been no increase in length mussel , argued that the death of her massive of the critical condition. In August analyzes , mussels predominate until 6.7 cm , and is currently fully curb the growth of mussel. Indicators of circles to represent dynamic growth rate of mussel growth in the period from April to June.
Keywords : shellfish, anaerobic conditions, samples, chemical compounds