Natural and anthropogenic conditions of water level fluctuations in lakes – Lake Powidzkie case study (Central-Western Poland)

Abstract

The article presents the analysis of water level fluctuations in Lake Powidzkie in the years 1961–2015. The study shows a considerable decrease in mean water levels in the aforementioned multiannual period, averaging 9 cmꞏdecade−1. Such a situation is caused by natural as well as anthropogenic factors, co-determining water relations in the study area. The natural factors include the amount and distribution of precipitation, increase in air temperature and evaporation size, unfavourable relations between the lake and catchment or hydrogeological conditions. Anthropogenic factors particularly include long-term transformations of the natural environment in the region, currently associated with meliorations accompanying the nearby opencast brown coal mines and exploitation of groundwaters for municipal purposes. Water shortages occurring during dry periods were shown not to be compensated in the study area in humid years. This is particularly related to the regional lowering of the aquifer remaining in close relations with Lake Powidzkie. Counteracting the unfavourable hydrological situation is done through hydrotechnical infrastructure which partially limits water outflow from the lake through damming.

Effect of climate warming on a change in thermal and ice conditions in the largest lake in Poland – Lake Śniardwy

“…One of the most important variables for evaporation volume is water temperature (Aydin and Karakuş, 2016). As emphasised by Nowak and Ptak (2019), or Nowak and Ławniczak-Malińska (2019), evaporation from free water surface is an important element of its exchange, particularly in the case of large water bodies, including Śniardwy. According to global simulations, annual evaporation from the lake will have increased by 16% by the end of the 21 st century, and one of the primary factors will be the reduction of ice cover duration (Wang et al, 2018).…”

Influence of a lake on river water thermal regime – case study of Lake Sławianowskie and the Kocunia River (Pomeranian Lakeland, North Poland)

“…One of the most serious problems faced by humanity today is climate change Nowak, Ptak 2019;Ptak et al 2019b). In this context, it seems important to reduce greenhouse gases, thus inhibiting further increases in air temperature.…”

Recharge and drainage of lakes in the Powidzki Landscape Park in conditions of increased anthropogenic and environmental pressure (central-western Poland)

“…As a re sult, wa ter is drained from the lake. This phe nom e non was doc u mented in the years 2011-2015, when the area transitioned from the state of max i mum fill ing of lakes and the sur round ing aqui fers -as soci ated with ex cep tion ally high rain fall in the 2010/2011 win ter sea son (Nowak, 2018;Nowak and Ptak, 2019) -to the state of the ex treme hy dro log i cal and hydro geological low-wa ter pe riod in the au tumn of 2015. The great est wa ter loss was then observed in Lake Suszewskie (Fig.…”

“…It concerns many lakes of dif fer ent mor phol ogy, for which there is a dense mea sure ment and ob ser va tion net work pro vid ing longterm me te o ro log i cal, hy dro log i cal, and hydrogeological data. It was pos si ble to study how these re la tion ships changed over the years un der the in flu ence of var i ous en vi ron men tal factors, in clud ing the ob served de te ri o ra tion of cli ma tic con ditions (Kę dzio ra, 2008;Przybyłek and Nowak, 2011;Nowak, 2018;Nowak and Ptak, 2019). Var i ous forms of hu man ac tiv ity (min ing, ground wa ter ab strac tion, water trans fers out of the catch ment area, wa ter stor age) that have af fected wa ter re sources in the re gion pro vided the oppor tu nity to es tab lish to what ex tent anthropogenic pres sure af fects lakes and the con nected ground wa ter.…”