Research of sphagnum moss productivity in Polistovsky Reserve
One of the directions of scientific research in Polistovsky Reserve is determination of productivity of sphagnum mosses - the main inhabitants of the bogs.
Productivity of a plant community (phytocenosis) is estimated as the amount of organic mass produced by phytocenosis per unit of area per unit of time. 90% of the territory of Polistovsky Reserve is covered by bogs, mostly raised bogs. The main source of plant organic mass on open or almost treeless bog is sphagnum moss. On transitional bogs this moss also has high productivity, a little less than productivity of oppressed bog trees.
To determine productivity of the most common species of sphagnum moss in different types of bogs and its annual dynamics researchers of Polistovsky Reserve conduct periodic monitoring of sphagnum moss productivity. Observations begin in April, after snow melt, and end at the end of October - November, when the growth of mosses practically stops. To calculate the productivity you need to know three parameters: the linear growth during the growing season (the period of the year when the climate is prime for plants to experience the most growth), the density of individual plants per unit of area, and weight of moss grown up during the season.
At the beginning of observations small metal pegs are inserted into the moss. The horizontal line of a peg corresponds to the heads of sphagnum. This is the zero point of reference. Increment is measured about once a month, i.e. how many millimeters above the zero point does sphagnum moss grown. From 20 to 50 pegs are inserted for each moss species. There is also another technique for measuring moss growth using plastic pipes. A pipe is wrapped with foil and inserted into the moss, then a line is drawn on foil above the heads of sphagnum by waterproof marker. A month later, when the sphagnum moss grows up, the next line is drawn, etc. At the end of the season the foil is removed, and the increase is measured using these drawn lines.
The density is measured at the end of the season by the frame size of 10 by 10 cm. The frame is placed on a moss and photographed. 3 measurements made for each kind of moss. Then the number of individual plants in the area bounded by the frame are calculated in laboratory conditions.
Then 100 individual plants of each moss species are selected, and a piece of it corresponding to an average increase for the season is cut from each plant. Then each sample is dried in a drying oven until completely dry condition and weighed. The weight of the sample is multiplied by density; as a result, we have productivity of a certain kind of sphagnum on an area of 1 square decimeter. If necessary, it can be counted on any area, for example in kilograms per hectare.
In 2016, accounting pegs and pipes were set on the 5th of April on transitional bog near ecotrail "Mossmen route", and on the 6th of April - on the raised bog near Nesvino tract. Observations will be held regularly throughout the summer and will be finished at the end of the season - in autumn.