Lake water stage dynamics in the Łęczna-Włodawa Lake District in 1991-2010In the years 1991-2010 the water stages of 38 lakes in the Łęczna-Włodawa Lake District were observed. Water stage dynamics of the Łęczna-Włodawa lakes was varied. A multi-annual trend with seasonal water stage variability was clearly observable. Low water stages were observed in the years 1994-1996 and 2004-2005, whereas the highest water stages were reported for 2002 and 2010. The water stages of Lake Piaseczno, the deepest lake, were consistent with solar activity changes. Land improvement works in the Łęczna-Włodawa Lake District and black coal mining caused further local changes in the directions of flow of surface and underground water, as well as modifying the water stage regime of some of the lakes.

This study presents changes in water conditions in the Lublin agglomeration, especially as regards discharges from the Bystrzyca and other rivers. Areas covered with impermeable materials, such as asphalt and concrete, have caused changes in directions of surface runoff and an intensifi cation of this process, with effects on the discharges of rivers. The regime of fl ooding is the consequence of natural and anthropogenic conditions. Spring and summer fl oods in Lublin and at water gauges below the city are mainly caused by surface runoff from the urban area. During periods of snowmelt periods or torrential rain, water fl ows rapidly through the system of stormwater drainage, and then into the rivers.

Poland is mostly a lowland country. About 90% of the country, especially its central and northern parts, lies at elevations less than 300 m above sea level. The remaining territory are highlands that lie at elevations of 300-612 m, and mountains that usually lie at elevations of up to 1,200 m, with the highest peak at 2,499 m. The division of Poland into hydrogeological regions is linked to the geographic division of Poland. The Hydrogeological Atlas of Poland (Paczynski, 1995) identifies three regions: lowland, highland, mountain. A newer and more detailed system of classification identifies 161 bodies of groundwater in Poland (Paczynski and Sadurski, 2007). Lowland parts of Poland were shaped by a Pleistocene ice cap. Therefore, the surface of the land is rich in glacial features and A summary of the current body of knowledge on springs in Poland is presented. The paper relates the location of springs to geological structure, spring discharge, use of particular springs as well as threats associated with local groundwater nitrate pollution. Other key points include the uneven distribution of springs across Poland as well as varying levels of understanding of springs in northern Poland and in certain mountain ranges. The paper ends with a recommendation to monitor more springs over longer periods of time with respect to discharge and water quality.

Springs are objects of natural environment, which are studied by different scientific disciplines: geography, hydrology, hydrogeology, hydrochemistry, hydrobiology, ecology, environmental protection, landscape architecture, touring, archeology and ethnography. These objects, in both the past and the present, were of a great importance to man, who, in different ways and very willingly, used the clean water flowing out and the surrounding environment. Springs, giving rise to streams, which feed into larger rivers, have great scientific, economic, natural, landscape, cultural and even therapeutic values. They have been protected from devastation and pollution for centuries, mainly due to the rational and often iconic perception of them. They were and still are objects of mystification resulting from the assignment of miraculous properties to their water and fantastic legends and historical events to places where they flow out. The question of the origin of water coming from springs has always been vividly discussed. It has contributed to both the development of natural sciences and to the creation of fantastic theories pointing to a specific "power" of these places and healing properties of discharging water. Interesting descriptions of springs that draw people's attention have appeared in many travel experience stories, which brought them fame. Many springs have become places of worship, being famous for the descriptions of their healing abilities, related myths and fantastic phenomena, which additionally increased the desire to feel their "spirit". The area of Poland is already quite well recognized in the aspect of springs. The knowledge about Polish springs has definitely increased in recent decades, mainly as a result of research conducted at all academic centers of the country, as well as thanks to the work on consecutive charts of the Hydrographic Map of Poland. The oldest information about springs in Poland can be found in historical records as well as in information and descriptions prepared for the needs of mining and balneology. Specialist publications and monographic views on springs and other groundwater outflows appeared in the middle of the 18th century. The springs of Małopolska were recognized at earliest. In the second half of the 20th century scientific

Changes of springs' yield of Lublin Upland and Roztocze Region in 1998-2008 Lublin Upland and Roztocze region are known for the occurrence of a large number of springs of high yield. These springs are fed mainly from Cretaceous or Tertiary water-bearing horizon. In order to determine variability of springs' yield, 61 selected springs were analysed in spring periods of the years 1998-2008. Collected hydrometric materials allowed for comparing average and extreme yield values of springs in various physiographic regions within the period of 11 years. Average value was 76.1 dm3·s−1, while the mean of the minimal yields was 44.7 dm3·s−1 and of the maximal - 132.7 dm3·s−1. Coefficient of irregularity of the springs' yield ranged from 1.5 to 5.0, which may lead to the conclusion that the springs' yield is constant or varies slightly. In some cases the irregularity was higher but it was determined by hydrogeological, meteorological and local factors.