Environmental factors shaping water-peat vegetation and its neighbouring surface waters in Lower Silesian Forests (Western Poland)

Phytosociological and physicochemical studies of endangered habitats of swamp and peat-bog areas were carried out in the Lower Silesian Forest complex (Western Poland), in the vicinity of Węgliniec village. The total of 63 phytosociological relevés were made and three syntaxonomic units were distinguished as associations (Cicuto-Caricetum pseudocyperi, Typhetum latifoliae, Phragmitetum australis) and two as communities (with Sphagnum girgensohnii and with Juncus effusus). Using the phytoindication method, it was found that among four analysed habitat parameters (L – light availability, F – humidity, R – soil pH, N – soil nitrogen), only nitrogen content did not play a significant role in shaping the composition of these phytocoenoses. Physicochemical studies of surface waters using high performance liquid chromatography (HPLC) method indicated, among others, a higher level of nitrogen compounds in some samples. Concentrations of mineral substances dissolved in water usually exceeded limit values for class II waters. Species composition of phytocoenoses and values of parameters recorded in neighbouring surface waters indicated that mutual interactions of these habitat components clearly existed there.

ACTIVE MOSS BIOMONITORING USING THE «MOSS BAG TECHNIQUE» AT THE STATE MUSEUM-RESERVE «TSARITSYNO»

Moscow is a large metropolis in which the air is affected by the constant effects of chemicals produced by industrial facilities, vehicles, residential heating and other human activities on a daily basis. The protected and park areas on the territory of Moscow have an important recreational role, therefore, air quality control in these territories should be carried out first. Active moss biomonitoring has been used as an alternative method to conventional atmospheric monitoring for more than 40 years. This type of biomonitoring is successfully applied all over the world: in China, Serbia, Moldova, Azerbaijan, Italy, Romania, etc. In this study, active moss biomonitoring was used for the first time on the territory of the Tsaritsyno Museum-Reserve to assess the air pollution. The moss species Sphagnum girgensohnii was chosen for the experiment. Neutron activation analysis was used to determine the concentrations of the elements: Na, Mg, Al, Cl, K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni, Zn, Se, As, Br, Rb, Mo, Sr , Sb, Ba, Cs, La, Sm, Tb, Ce, Hf, Ta, W, Th, and U. The concentrations of Pb, Cu, and Cd were determined by atomic absorption spectrometry.

Active Moss Biomonitoring of Trace Elements Air Pollution in Chisinau, Republic of Moldova

For the first time active moss biomonitoring was used to assess trace element deposition in the capital of the Republic of Moldova, Chisinau. Moss Sphagnum girgensohnii samples were exposed in bags at three sites of Chisinau from October, 2016 to March, 2017. The content of 30 elements: Na, Mg, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, As, Br, Rb, Mo, Sr, Sb, Ba, La, Ce, Cs, Hf, Th, Cu, Cd, Pb, and U in the exposed and unexposed mosses was determined by neutron activation analysis and atomic absorption spectrometry. According to the relative accumulation factor, the most abundant elements in the samples were V, Cr, Fe, Ba, La, As, Sb, U, and Pb. Such elements as Cl, K, and Rb were depleted from the moss tissue during the time of exposure. Principal component analysis was used to identify and characterize different pollution sources. The obtained results indicate that the use of S. girgensohnii moss bags is a simple and inexpensive technique to monitor major and trace element content in the air of urban area.

Limitation of photosynthetic processes in photosystem II in alpine mosses exposed to low temperatures: Response of chlorophyll fluorescence parameters

In this study, we evaluated the effects of low and sub-zero temperature on the fast chlorophyll fluorescence transient (OJIP) and OJIP-derived parameters in 4 different mosses: Sphagnum girgensohnii, Polytrichum formosum, Hylocomium splendens and Pleurozium schreberi. The low temperature stress was applied on the mosses for 90 min. at 3 different temperatures (5°C, -1°C and -10°C). To investigate the effects of this stress on the functioning of photosystem II (PS II), the chlorophyll fluorescence measurements were taken at control temperature (22°C) and, after a 90 min. acclimation period, at each experimental temperature. The shape of OJIP curves and chlorophyll fluorescence parameters were found temperature-dependent in all the species. The mosses differed in their sensitivity to the stress but general trends in response to low temperature were similar. The results support the idea that S. girgensohnii is less resistant to low temperature stress than the other species. We were also interested in the K and L steps in OJIPs, representing different disorders caused by low temperature. The K-step was seen in P. formosum and P. schreberi and the L-step in H. splendens and S. girgensohnii.

Sphagnum invasion after clear-cutting and excavator mounding in a hypermaritime forest of British Columbia

Sphagnum invasion 8 years after an experimental clear-cut and mounding field trial was examined in a mesic western redcedar (Thuja plicata Donn ex D. Don) – western hemlock (Tsuga heterophylla (Raf.) Sarg.) forest on the outer north coast of British Columbia. Sphagnum invasion was prominent in wet hollows in the mounded blocks. Pioneer species, Sphagnum pacificum Flatb. and Sphagnum angustifolium (C. Jens. ex Russ.) C. Jens., were common despite being minor components in the precut forest. Sphagnum girgensohnii Russ., a species of forests, showed expanding colonies and contained some Sphagnum capillifolium (Ehrh.) Hedw. Comparisons of vertical growth and decomposition rates of Sphagnum in the experimental field site and in a nearby natural peatland suggest that peat accumulation potential in the Sphagnum colonies in the mounded blocks is similar to that in the natural peatland. These observations suggest that open peatland-type plant communities become established and paludification processes are beginning. Mounding may be an effective strategy for silvicultural management to improve tree growth in the short term but may initiate paludification and negatively impact forest productivity in the long term in hypermaritime lower productivity forests.