New records and noteworthy data of plants, algae and fungi in SE Europe and adjacent regions, 6

This paper presents new records and noteworthy data on the following taxa in SE Europe and adjacent regions: cyanobacteria Anagnostidinema amphibium, mycorrhizal fungus Tricholoma frondosae, stonewort Chara connivens, mosses Dicranum polysetum and Ulota intermedia, and dicots Eclipta prostrata, Paeonia daurica subsp. daurica, Ruta graveolens and Sorbus bosniaca.

Growth dynamics analysis of the acrocarpous moss Dicranum polysetum Sw. in artificial pine forests of the steppe zone

The paper discusses the growth dynamics of Dicranum polysetum Sw. in artificial pine communities of the Krasnosamarsky Forest (Samara Region) and the National Park Buzuluksky Bor (Samara and Orenburg Regions). These species are most commonly found in these types of communities. The authors note the vitality of Dicranum polysetum Sw. and its relation to the size of the moss curtain. The studies were conducted in the summers of 2015, 2016 and 2017. The moss was studied at 12 sites of the artificial pine forests of the Krasnosamarsky forest and the National Park Buzuluksky Bor. Three individuals were selected at each site, the growth and vitality of them were noted during the study period. It was revealed that the smallest growth was on the sites of the smallest moss curtain in both study areas. It was also found that the microrelief and grassy layer can significantly affect moss growth. It was noted that the vitality score was higher in large clumps in the absence of any mechanical damage to the curtain, and that the shoots form twigs, on average, every two years, thereby increasing their biomass, because the area of curtains did not significantly change during the study period.

Microsite conditions and spatial pattern in a boreal bryophyte community

This study addresses the hypothesis that the spatial pattern of four bryophyte species on the forest floor of boreal woodland represents habitat partitioning, corresponding to microhabitat heterogeneity. Temperature, vapour pressure deficit, photosynthetically active radiation, incident precipitation, and litter fall were monitored at locations of pure colonies of Pleurozium schreberi, Ptilium crista-castrensis, Dicranum polysetum, and Ptilidium ciliare. From May through November 1990, the species received a mean total of 51.20 ± 1.09 cm of rain and 1.034 ± 0.639 g of litter, primarily spruce needles. They experienced temperatures as high as 40 °C, vapour pressure deficits to 7.3 kPa, and photosynthetically active radiation to 3200 μmol∙m−2∙s−1. The results do not support habitat partitioning by the species on the basis of the variables examined: all four species tolerated the full range of conditions and their combinations that occurred in the study season, and experienced the same ranges during > 90% of the sampling period, with equally broad within-species variation. Although large pure colonies of P. ciliare were delimited by microsites receiving greater spruce needle litter fall and lower incident precipitation per rainfall event, smaller colonies and individual shoots were often found in mixture with other species. Overall, the spatial pattern did not correlate with microsite conditions, and we see no evidence of habitat partitioning in terms of currently occupied microsites. Key words: community structure, microclimate, Pleurozium schreberi, Ptilium crista-castrensis, Dicranum polysetum, Ptilidium ciliare.

The mineral content of Sphagnum fuscum as affected by human settlement

Nine samples of Sphagnum fuscum (Schimp.) Klinggr., one each of S. magellanicum, S. nemoreum, S. wulfianum, and Dicranum polysetum, and seven samples of Larix laricina have been analyzed for mineral ash content, Al, B, Ca, Fe, K, Mg, Mn, and P. The chief influence upon the ash content of Sphagnum fuscum in ombrotrophic bogs which are dependent for their mineral supply solely upon the atmosphere is clearly windblown soil from cultivated farmlands. Bogs unaffected by human settlement and therefore not subjected to greater mineral supply are now restricted to wilderness areas in the northeastern part of Minnesota. Sphagnum serves as an effective trap for dust fall and is much richer in the lithophile elements Al and Fe than the needles of the tamarack, Larix laricina, from comparable habitats. Presumably dust fall is readily washed off the tree needles by rain. Larix concentrates B to a much greater degree than does Sphagnum.

Moisture stress and its effect on photosynthesis in Dicranum polysetum

The effect of water stress on the moss Dicranum polysetum Sw. was studied in the growth chamber, and water potential (ψ) was found to vary as much as 15 atm between the tip of the plant and areas 2 to 4 cm within the cushion, which suggests that very little water is transported from the base of the stem to its tip. With an infrared gas analyzer it was determined that photosynthesis ceases at −21 to −23 atm and the moss remains dormant until it is rewetted. Upon rewetting, there is a sharp burst of respiration that doubles the normal CO2 output. This burst reached its maximum level of 4 mg CO2 g−1 h−1 within 15 min and was of short duration. Full photosynthetic rate was restored in 8 h.