Seasonal Changes in the Photosynthetic Activity of Terrestrial Lichens and Mosses in the Lichen Scots Pine Forest Habitat

Photosynthetic activity is one of the most important metabolic processes that can be quickly and easily studied in the field. It can be used for identifying the environmental factors affecting ecosystem balance, as any stressor influencing metabolic and physiological processes will have a measurable effect on photosynthesis. The aim of this study was to measure the photosynthetic activity of selected lichens and mosses and investigate its changes resulted from diurnal and seasonal variability. We studied two lichens (Cladonia mitis Sandst and Cladonia uncialis (L.) Weber ex F.H. Wigg.) and two mosses (Pleurozium schreberi (Willd. ex Brid.) Mitt. and Dicranum scoparium (L.) Hedw.). Samples were collected in the area of lichen Scots pine forest of the “Bory Tucholskie” National Park. Our study revealed that the photosynthetic activity of cryptogams depended on species, season, time of the day, and water availability. Cladonia species, which are the main component of lichen Scots pine forests, have higher photosynthetic activity than Pleurozium schreberi, which represents species of fresh coniferous forests. Photosynthetic activity increased from spring through summer and reached the highest values in autumn. It was also higher in soaked samples collected in the morning and afternoon compared to noon. Despite the water access, noon samples still showed the lowest activity. This can result from natural changes in humidity during the day to which cryptogams are well-adapted.

Genetic Diversity and Population Structure in Bryophyte With Facultative Nannandry

Among plants, gender dimorphism occurs in about 10% of all angiosperms and more than 50% of all moss taxa, with dwarf males (DM) found exclusively in some unisexual mosses. In this study, we explore the role of male dwarfism as a reproductive strategy in the widespread acrocarpous moss Dicranum scoparium, which has facultative male dwarfism, having both dwarf males (DMs) and normal-sized males (NMs). We retrieved 119 SNP markers from transcriptomes which were used to genotype 403 samples from 11 sites at seven localities in southern Sweden. Our aims were to compare the genetic variability and genetic structure of sexually reproducing populations at different geographic levels (cushion, site, and locality) and compare in particular the relative contribution of females, dwarf males and normal-sized males to the observed genetic diversity. The numbers of DMs differed strongly between sites, but when present, they usually outnumbered both females and NMs. Low genetic differentiation was found at locality level. Genetic differentiation was strongest between cushions for females and NMs and within cushions for DMs indicating small scale structuring and sometimes inbreeding. NMs were more clonal than either DMs or females. Genetic diversity was similar between females and DMs, but lower for NMs. Two haplotypes were shared between females and DMs and one haplotype was shared between a DM and a NM. In conclusion, our results show that DMs and NMs play different roles in reproduction, inbreeding may occur at cushion level, but gene flow is high enough to prevent substantial genetic drift.

Wood Ash Application Reduces Bryophyte Cover and Changes Species Composition in a Norway Spruce (Picea abies) Plantation

Return of wood ash from power plants to plantations makes it possible to recycle nutrients, counteract acidification, and to reduce economically costly waste deposition of the wood ash. However, current legislation restricts the amount of wood ash that can be applied and it is desirable to increase the allowed application dose, if possible, without negative effects on the plantation ecosystems. Here, we applied wood ash in levels corresponding to 0, 3, 9, 15, 30, and 90 t ash ha−1 and monitored the effect of the different ash doses on bryophytes in a Norway spruce (Picea abies) plantation with a dense bryophyte cover dominated by Hypnum jutlandicum, Dicranum scoparium, and Pleurozium schreberi. We used two complementary methods, image analysis, and pinpoint registration during a three-year period. To our knowledge, we are the first to apply this combined effort, which provides a much more exhaustive description of the effects than the use of each method separately. Moreover, the inclusion of a wide range of different wood ash levels enabled us to establish detailed dose-response relationships, which previous authors have not presented. The bryophyte cover decreased with increasing ash level with concomitant changes in species composition. At ash doses above the currently allowed 3 t ha−1, the ash significantly reduced the bryophyte cover, which only re-established very slowly. With increasing wood ash dose, the dominating species changed to Brachythecium rutabulum, Ceratodon purpureus, and Funaria hygrometrica. We conclude that application of more wood ash in spruce plantations than currently allowed will reduce total cover of bryophytes and cause a pronounced change in bryophyte species composition. These changes will in particular harm bryophyte species with specific environmental requirements and generally impair the bryophyte cover as habitat for invertebrates and its economic value for moss harvesting.

Vertical structure of phytocenoses of the Kurort forest Park of St. Petersburg

Курортный лесопарк Санкт-Петербурга, площадью около 23 тыс. га, расположен на землях города, является важнейшим компонентом биосферы. Леса города выполняют защитные, санитарно - гигиенические, рекреационные функции, являются резервуаром чистого воздуха для Санкт-Петербурга. Лесопарк разделен на 6 участковых лесничеств: Комаровское, Песочинское, Молодежное, Приморское, Сестрорецкое, Кипенское, которые находятся на землях административных районов города - Курортном, Приморском, Выборгском, Петродворцовом, Красносельском и Колпинском. Лесопарк используется для отдыха жителями мегаполиса, что отражается на вертикальной структуре фитоценозов. В Курортном лесопарке произрастают растения разных биоморфных групп: деревья, кустарники, травы, мхи. Для каждой группы растений проведены лесоводственные исследования, установлено, что преобладают одноярусные древостои: сосны обыкновенной ( Pinus sylvestris L.), ели европейской ( Picea abies L.), берёзы пушистой ( Betula pubescens Ehrh.). Подлесок представлен аборигенными видами растений: рябина обыкновенная ( Sorbus aucuparia L.), крушина ломкая ( Frangula alnus Mill),черемуха обыкновенная ( Prunus padus L), бузина обыкновенная ( Sambucus racemosa L.), жимолость обыкновенная ( Lonicera xylosteum L.), смородина красная ( Ribes rubrum L.). В травяно-кустарничковом ярусе преобладают: кислица обыкновенная ( Oxalis acetosella L.), черника обыкновенная ( Vaccinium myrtillus L.) и брусника обыкновенная ( Vacciniumvitis- idaea L.). Мохово-лишайниковый ярус представлен следующими видами мхов: дикранум гладкий ( Dicranum scoparium Hedw.), плевроциум Шребери ( Pleurozium schreberi Brid.), гилокомиум блестящий (Hylocomium proliferum Brid.), кукушкин лён обыкновенный ( Polytrichum commune Hedw.). Лесоводственные исследования необходимы для понятия структура городских лесов Санкт-Петербурга. Kurort forest Park of St. Petersburg with an area of about 23 thousand hectares is located on the land of the city, is an important component of the biosphere. Forests of the city perform protective sanitary and hygienic recreational functions, are a reservoirof clean air for St. Petersburg. Forest Park is divided into 6 sub-districts.: Komarovsky, Pesochinsky, Youth, seaside, Sestroretskoe, Kopanskoe who are in the land of administrative districts of the city - Kurort, Primorsky, Vyborgsky, Petrodvortsovy, Krasnoselsky and Kolpino. The forest Park is used for recreation by residents of the metropolis which is reflected in the vertical structure of the phytocenoses of the Kurort forest Park plants grow different biomorphic groups: trees, shrubs, herbs, mosses. For each group conducted forestry studies found that dominated by single-tiered, stands dominated by Scots pine ( Pinus sylvestris L.), spruce European ( Picea abies L.), birch fluffy ( Betula pubescens Ehrh.). The undergrowth is represented by native plant species: Rowan ( Sorbus aucuparia L.), brittle buckthorn ( Frangula alnus Mill.), bird cherry ( Prunus padus L.), elderberry ( Sambucus racemosa L.), honeysuckle ( Lonicera xylosteum L.), red currant ( Ribes rubrum L.). In the herb-dwarf shrub layer dominated by common sorrel ( Oxalis acetosella L.), bilberry ( Vaccinium myrtillus L.), and red bilberry ( Vaccinium vitis-idaea L.). Mosslichen layer is represented by the following species of mosses: dicranum smooth ( Dicranum scoparium Hedw.), Pleurozium Schreberi ( Pleurozium schreberi Brid.), Hylocomium brilliant ( Hylocomium proliferum Brid.), common cuckoo flax ( Polytrichum commune Hedw.). Such studies are necessary for the concept of the structure of urban forests in St. Petersburg.