The first data about economical development of Žuvintas catchment obtained from the middle of XVI century. Agricultural lands as well as marshes and lakes covered around 30 % each of the total territory, whereas the rest 40 % were overgrown with forests. The substantial part of those forests lied to the North and West of Žuvintas and Dusia Lakes. Great part of the territory between these Lakes was converted and use for the agricultural purposes.

The most intensive agricultural activities were executed during the period of 3-4 decades of XX century.

Almost all the surrounding marshes of the territory started to drain very long time ago. Technical drainage project for the watercourse of Dovine River and adjacent wetlands was prepared on 1909, and implemented in the period of 1912-1914. The waterlogged peasant’s lands were drained during the 1920-1940. The drainage of Soviet collective farms started since year 1953. 3 sluices (floodgates) were constructed on the outflow of rivers Dusia, Simnas and Žuvintas lakes in order to regulate run-off water for the whole Dovinė River basin during 1968 – 1972. Therefore the discharge and the water level regime of Žuvintas Lake were changed considerably. Special embankment to sustain water level in the raised bog was mounded in the northern part of Žuvintas Nature Reserve.

Wetlands melioration had negative influence for upon the sustainability of the Biosphere Reserve. The drainage of the adjacent Žuvintas wetlands also caused the reduction of the water level in the Reserve territory. It caused the great changes in the hydrology regime and unbalanced the evolution processes of natural ecosystem: wetlands degrade, and overgrow with forest stands.

Amalvas marshy complex has suffered the most severe in Žuvintas Biosphere Reserve.