Strzalowo is a Polish demo area with the aim to demonstrate the adaption of riparian forest and the comparison of the difference in water quality (in chemical terms) in a river flowing through forest areas and meadows.
Mean annual temperature: 7,6°C
Growing season: 180-190 days
Annual precipitation: 590 millimetres
Middle boreal forest vegetation zone: temperate forest
The demonstration object is located in the Piska Forest in the area of the Forest District of Strzałowo and is located on a watercourse called Gardynka, which flows out of Lake Kołowin Mały and flows into Skok Lake and further to the Krutynia River. This river was probably regulated in the 19th or early 20th century and currently has the character of a channel. The difference in the water level between the highest and the lowest point on the 1 600 meter long section of the river is 1,4 meters. The river Gardynka on the on the demo area section is supplied with several ditches and waters flowing out of aquifers in the form of springs. The stands occurring here are multi-species, but there are mostly tree stands with a large share of pine (50-80 percent). Forest habitats predominate, and therefore relatively fertile in various variants of water conditions (fresh forest, mixed fresh forest, mixed swamp forest). These are tree stands mainly in medium and older age classes.
Conducted work and time plan for future activities
Water in the watercourse and groundwater in wells are controlled three times a year from August 2016. Observations of changes in physicochemical parameters of water occurring as a result of forest operations in surrounding forests are carried out. In recent years, the decline in the dieback of spruces has been observed, which necessitates their removal and partial reconstruction of stands. In addition, the oldest stands will be gradually removed, and the forest area will be renewed. It can be expected that changes in tree stands will cause changes in water chemistry. In the future, observations are planned regarding changes in tree stand in surface and underground water quality.
Installations of infrastructure
To control the quality of groundwater flowing into the watercourse, one well was installed on both banks in the forest area and one well in the meadow (about 1 kilometre away). Surface water for testing is taken approx. 150 meters before wells in the forest, at the height of well in the forest, at the level of the well in the meadow and about 1,5 kilometres after the last well (there is again the forest). The scheme below presents the locations of sampling water in the river and groundwater for chemical analyzes.