Zemaitija Integrated Monitoring Station: LTER_EU_LT_006 - Lithuania

Zemaitija station (LT03) was founded in the strict reserve zone of Zemaitija national park, at the basin of right side Uođa river tributary - Juodupis brook. The area of the basin is 147.3 ha. The lowest place - 147.0 m, the highest elevation - 180.0 m above sea level. The geographical co-ordinates of the basin are: longitude - 21*51*56*-21*53*10*, latitude - 56*00*19*-56*01*05*. Zemaitija station is situated at 50 km distance from the Baltic Sea, which generally defines the climatic conditions of this territory. High humidity, cloudiness and abundant precipitation are typical for the assessment location. The perennial air temperature is 5.9 C, the perennial average amount of precipitation reaches up to 788 mm and is significantly higher than in other stations. The length of vegetation period is 187 days. The geomorphologic structure of the basin is also relatively complicated. Different than in other locations, in this station the marsh accumulation forms with organic sediments transfer into limnoglacial accumulative forms and glacioacval accumulative sandy hilly formations with typical limnoglacial sand. Saturation of Juodupis river water had very little mineralisation, with oxygen levels of 9.6 mg/l and average yearly mineralisation of 163 mg/l, and the pH fluctuated in the limits of 6.65-7.90, being slightly alkaline. Annual yearly concentration of nitrates is 0.37 mgN/l. Significant increases in the number of nitrate ions were indicated in 1997, i.e., concentration increased twice compared to 1996. Concentrations of nitrogen are not significant. Concentrations of common phosphor and silicon are very small. Conifers dominate the basin of this brook, which are mainly spruce with up to a 20-30% pine mixture. Abundant spruce under layer is common for these stands. A significant territory of the basin is also covered by pure spruce stands. However, as a rule in these forest stands we can find an abundant second spruce layer or under layer. The number of birch and black alder stands is even lower in Zemaitija station. They can be found only at the source of the river, where marsh habitat types are dominating. Forest stands with two or more age classes are dominating in Zemaitija station. This is mainly multi-layered spruce stands and pure pine or pine mixed with abundant spruce under layer forest stands. A slightly smaller territory is occupied by mature forest stands and young forests. The main vegetation communities are: sub-oceanic blueberry western taiga, marsh boreal spruce forests and boreal marsh Scotch pine forests. Eleven plant communities can be identified in the river basin.