Long-term Development of the Hydroecosystem of the Lake Engure and its Influencing Factors

Investigations of water chemical composition and biota of Lake Engure have been carried out since 1995 by using standard methods for inland surface waters. Time series of air temperature and precipitation for the Mersrags meteorological station for the period 1928 to 2009 are used for the trend analysis. The results show that the long-term development of the hydroecosystem is related to such environmental factors as the lake's geographical location, basin and morphology, as well as the lake's history and relationship of biotic and abiotic factors.