44
R. Cie´ sli´ nski
on the use of dams, use of groundwater and surface water, the release of wastewater
into surface water and groundwater, employment of drainage works in construction,
and the establishment of hydroelectric facilities. In addition, some forms of environmental protection provide a guarantee that no construction will take place and no
homes will be built. This applies to national parks. Other forms of environmental
protection provide for limited construction opportunities. The greatest problem for
protected areas is new construction in so-called near-park or near-reserve areas.
3.5 Lakes and Threats to Lakes in National Parks in Poland
This section of the paper provides information on lakes, current threats, and potential
threats to lakes found in national parks with the largest water capacity in Poland.
Babiogórski National Park—characterized by the presence of numerous small
landslide lakes recharged by groundwater. Of the 18 lakes in the area, 13 are permanent. At high water stages, water covers an area of about 0.4 hectares. The largest
lake, Mokry Stawek, has an average area of 450 m
2 with a maximum of 1,500 m
2 .
Its average depth is 2.5 m with a maximum of 5 m. It does dry out or spill out occasionally [14]. The lake used to be a swimming hole and boating area before World
War II. Today the lake is still popular with tourists, which has not yet produced any
deterioration in the lake basin [15]. Lakes in Babiogórski National Park were also
used as watering holes for sheep and cattle until the mid-twentieth century. This
practice ended when the park was officially established [16]. The mineral content
of the park’s lake water is low. The lake water pH is neutral. The lakes feature high
oxygen content and low biogenic substance content [17], which also means that water
quality is very high. The highest mineral content is observed in winter and the lowest
during the spring snowmelt season [15]. The main threats to the lakes today are air
pollution arriving from nearby areas, wastewater treatment facilities needed to serve
a growing number of tourists, and increasing vehicular traffic [14, 18].
Drawie ´
nski National Park features 20 lakes characterized by variable
morphology and trophic state. The largest lake is called Ostrowiec and has an area
of 369.9 hectares and a maximum depth of 28.5 m [19]. Another large lake is called
Płociczno, which is characterized by high susceptibility to degradation due to its
large catchment area to lake area ratio [20] and contaminated sediments [21]. The
park also includes hydrologically unique Lake Czarne—a charophyte lake—whose
waters undergo exchange once every 20 years. The park features more lakes of this
type but also features dystrophic lakes [20]. Fishing is possible on a seasonal basis
in some lakes in the park (Ostrowite, Sitno). Tourists may also kayak on some of the
lakes or camp lakeside. Water quality in the park’s lakes varies. Charophyte lakes
are characterized by very good water quality.
On the other hand, some of the park’s lakes are strongly eutrophic and feature poor
quality water, gauged via high concentrations of biogenic substances, low water transparency, oxygen deficits, and high trophic state. The main threats to surface waters
in Drawie´ nski National Park include kayaking, vehicular traffic, parking spaces, and
R. Cie´ sli´ nski
on the use of dams, use of groundwater and surface water, the release of wastewater
into surface water and groundwater, employment of drainage works in construction,
and the establishment of hydroelectric facilities. In addition, some forms of environmental protection provide a guarantee that no construction will take place and no
homes will be built. This applies to national parks. Other forms of environmental
protection provide for limited construction opportunities. The greatest problem for
protected areas is new construction in so-called near-park or near-reserve areas.
3.5 Lakes and Threats to Lakes in National Parks in Poland
This section of the paper provides information on lakes, current threats, and potential
threats to lakes found in national parks with the largest water capacity in Poland.
Babiogórski National Park—characterized by the presence of numerous small
landslide lakes recharged by groundwater. Of the 18 lakes in the area, 13 are permanent. At high water stages, water covers an area of about 0.4 hectares. The largest
lake, Mokry Stawek, has an average area of 450 m
2 with a maximum of 1,500 m
2 .
Its average depth is 2.5 m with a maximum of 5 m. It does dry out or spill out occasionally [14]. The lake used to be a swimming hole and boating area before World
War II. Today the lake is still popular with tourists, which has not yet produced any
deterioration in the lake basin [15]. Lakes in Babiogórski National Park were also
used as watering holes for sheep and cattle until the mid-twentieth century. This
practice ended when the park was officially established [16]. The mineral content
of the park’s lake water is low. The lake water pH is neutral. The lakes feature high
oxygen content and low biogenic substance content [17], which also means that water
quality is very high. The highest mineral content is observed in winter and the lowest
during the spring snowmelt season [15]. The main threats to the lakes today are air
pollution arriving from nearby areas, wastewater treatment facilities needed to serve
a growing number of tourists, and increasing vehicular traffic [14, 18].
Drawie ´
nski National Park features 20 lakes characterized by variable
morphology and trophic state. The largest lake is called Ostrowiec and has an area
of 369.9 hectares and a maximum depth of 28.5 m [19]. Another large lake is called
Płociczno, which is characterized by high susceptibility to degradation due to its
large catchment area to lake area ratio [20] and contaminated sediments [21]. The
park also includes hydrologically unique Lake Czarne—a charophyte lake—whose
waters undergo exchange once every 20 years. The park features more lakes of this
type but also features dystrophic lakes [20]. Fishing is possible on a seasonal basis
in some lakes in the park (Ostrowite, Sitno). Tourists may also kayak on some of the
lakes or camp lakeside. Water quality in the park’s lakes varies. Charophyte lakes
are characterized by very good water quality.
On the other hand, some of the park’s lakes are strongly eutrophic and feature poor
quality water, gauged via high concentrations of biogenic substances, low water transparency, oxygen deficits, and high trophic state. The main threats to surface waters
in Drawie´ nski National Park include kayaking, vehicular traffic, parking spaces, and