Changes in the Water Resources of Selected Lakes in Poland in the Period 1916–2020 as Information to Increase Their Availability

Abstract

The historical effects of land development on water management currently require a new approach, in many cases involving attempts at the restoration of the quasi-natural state. This is evident in reference to many regions in Poland, where the hydrographic network has been diminishing over the centuries, among others in favour of obtaining new agricultural land. Such activities overlap with natural processes causing transformations of the hydrosphere. The most serious problems currently include water deficits resulting from climate change and human activity. This paper employed archival bathymetric maps from the beginning of the 20th century for the determination of the scale of changes in the morphometric parameters of six lakes in western Poland. It was determined that over a period of more than a hundred years, the surface area (12.2%) and original volume of water bodies (13.9%) were largely reduced. This situation was caused by both natural (overgrowing and shallowing) and anthropogenic (change in water level) factors. The obtained information points to the need of an inventory of historical bathymetric maps of lakes. In combination with modern research, this will allow for the determination of changes in the water resources of lakes and, in a longer-term perspective, potential possibilities of their renaturisation. This knowledge is important in the context of the reconstruction of water resources in the territory of Poland, where their deficits are recorded increasingly frequently. It should also be emphasised that the restoration of the natural capacity of water retention in lakes is a more economical solution and, most importantly, it is not invasive for the environment.

Ecological and Health Risk Assessments of Heavy Metals Contained in Sediments of Polish Dam Reservoirs

“…Answering the question, however, requires expanding the monitoring network to cover all parts of reservoirs. The accumulation of sediments in reservoirs leads to their shallowing [93,94]. Due to this, works are periodically conducted aimed at their removal from the reservoir.…”

Hydraulic Structures as a Key Component of Sustainable Water Management at the Catchment Scale—Case Study of the Rgilewka River (Central Poland)

“…Water is not perceived as a factor hindering agriculture. On the contrary-its shortages may contribute to losses in this economic sector [14]. In the context of proper management of water resources, suppressing its excess-commonly identified as a flood-is also essential.…”