Whole Curonian Lagoon in the southeast Baltic Sea during the period 1967-1992 (data set limits: 54 54 - 55 44N; 20 37 - 21 16E); Northern Curonian Lagoon since 1993 (data set limits: 55 16 - 55 44N; 21 01 - 21 17E)

Ammonium and ammonia concentration parameters in water bodies; Nitrate concentration parameters in the water column; Nitrite concentration parameters in the water column; Phosphate concentration parameters in the water column; Silicate concentration parameters in the water column

Discrete water samplers; spectrophotometers; nutrient analysers

Nutrients are one of the most important components of an ecosystem, as a regulator of intensity of biological processes and a symptom of eutrophication in the natural water-bodies as well as the Curonian Lagoon. The purpose of the research is to evaluate the hydrochemical state of the Curonian Lagoon, its seasonal and long term changes and influence on water quality, primary production. From 1967 to 1974 only some forms of nutrients (phosphate, silicate and nitrite) were investigated. Analyses of total phosphorus and ammonium were started in 1975, analyses of nitrate - in 1977, analyses of total nitrogen - in 1979. During that period from 1967 to 1979 sampling was performed three times a year (spring, summer, autumn). Regular investigations of all forms of nutrient (phosphate, total phosphorus, silicate, nitrite, nitrate, ammonium and total nitrogen) were performed since 1980 every month. In accordance with the national Curonian Lagoon monitoring programme nutrient sampling from 1967 to 1992 was carried out in the whole Curonian Lagoon by the expedition cutter 'Gintaras'. Since 1993 research is carried out in the north part of the Lagoon which belongs to Lithuania. The data are fully quality controlled. Systematic certification of laboratories, participation in international intercalibrations, internal control, introduced managing system for research' quality, use of high quality reagents determine quality of data. All data is stored in archive (in table forms on paper) and is saved on hard disk.

A. Jasinskaite (1998) The long-term changes of the nutrients in the Kurshiu Marios Lagoon / The environmental status of the Baltic Sea and Kurshiu Marios Lagoon (Articles in Lithuanian with English summaries), Virginija Cizauskiene; A.Jasinskaite (2008) Nitrogen and phosphorus in the Curonian Lagoon and Baltic coastal zone / Monograph: The Baltic Sea and its problems (Articles in Lithuanian with English summaries), N.Remeikaite, R.Nikzentaitiene

Department of Marine Research of the Environmental Protection Agency
Taikos Av. 26
Klaipeda

LT-91149
Lithuania