The unusual inter-tidal niche of the rare moss Bryum marratii Wilson

This is the first detailed ecological investigation of the rare moss Bryum marratii Wilson. Results show occupancy of a niche at the two study sites that is unusual amongst bryophytes, within the upper edge of saltmarsh. All colonies (n = 120), which comprise the largest populations in Wales, occur in an elevation zone of just 57 cm and are subject to frequent inundation by higher spring tides. In total, the average location of a B. marratii colony was submerged by seawater 3.6 day-1 yr-1. Sea level rise, projected in the study region to be 30–46 cm during the current century, is a major threat to the long-term survival of these population

Endozoochory of large bryophyte fragments by waterbirds

Dispersal is a fundamental requirement for all organisms, indeed theoretical arguments show that dispersal is still required even in a uniform and predictable environment, and it is obviously a key mechanism by which plants respond to climate change (Hamilton & May, 1977; Huntley & Webb, 1989). In bryophytes, spores provide an especially important means of dispersal (Glime, 2014; Porley & Hodgetts, 2005), and are often small enough to potentially be moved between continents in the atmosphere (Wilkinson et al, 2012). However, waterbirds are also major vectors for a broad range of plant types (Green et al., 2016), and it is likely that bryophyte spores are dispersed by migratory waterbirds, both by epizoochory (external dispersal on plumage or feet) and endozoochory (internal dispersal after ingestion and survival of transit through the gut). Indeed, Proctor (1961) showed experimentally that spores of the liverwort Riella americana survive gut passage through Mallards (Anas platyrhynchos)

Impact of changing climate on bryophyte contributions to terrestrial water, carbon, and nitrogen cycles

Bryophytes, including the lineages of mosses, liverworts, and hornworts, are the second-largest photoautotroph group on Earth. Recent work across terrestrial ecosystems has highlighted how bryophytes retain and control water, fix substantial amounts of carbon (C), and contribute to nitrogen (N) cycles in forests (boreal, temperate, and tropical), tundra, peatlands, grasslands, and deserts. Understanding how changing climate affects bryophyte contributions to global cycles in different ecosystems is of primary importance. However, because of their small physical size, bryophytes have been largely ignored in research on water, C, and N cycles at global scales. Here, we review the literature on how bryophytes influence global biogeochemical cycles, and we highlight that while some aspects of global change represent critical tipping points for survival, bryophytes may also buffer many ecosystems from change due to their capacity for water, C, and N uptake and storage. However, as the thresholds of resistance of bryophytes to temperature and precipitation regime changes are mostly unknown, it is challenging to predict how long this buffering capacity will remain functional. Furthermore, as ecosystems shift their global distribution in response to changing climate, the size of different bryophyte-influenced biomes will change, resulting in shifts in the magnitude of bryophyte impacts on global ecosystem functions

The distributon of Bryophytes in Lancashire: patterns, causes and consequences

This thesis investigates the patterns, causes and consequences of bryophyte distributions in Lancashire (north-west England). At a habitat scale, it is shown that species are spatially clustered and exhibit similarities in their ecologies within clusters, related in particular to gradients in disturbance and soil moisture. At a landscape scale. altitude is most strongly associated with differences in species distributions, correlated with important changes in habitats, water availability, nutrient availability and substrate pH. Changes in the solid geology also had an important influence in North Lancashire, where large exposures of limestone exist. Also at a landscape scale, high species-richness was found to be associated with high water availability, low nitrogen deposition and high cover of broad-leaved woodland.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

The identification and distribution of Sphagnum balticum (Russow) C.E.O.Jensen in Britain

Introduction. The aims of this study were to help clarify the identification of Sphagnum balticum in Britain, to review its distribution, and to investigate the possible presence of hybrids between it and either S. cuspidatum or S. fallax. Methods. All sites at which Sphagnum balticum has been recorded recently in Britain were visited in 2020, and a search made for it and other species with which it could be confused, together with possible hybrids. Samples were collected when suitable material was found. DNA was extracted from 31 shoots, each representing one field sample. Fifteen microsatellites that have been developed for Sphagnum species were amplified and genotyped. The genetic structure of the data was investigated using principal coordinate analysis and cluster analysis. Results. The results of the genetic analysis support the recognition of four taxa, which corresponded to four morphologically identified taxa: Sphagnum angustifolium, S. balticum, S. cuspidatum and S. fallax. There was no evidence of hybrids. Over-recording of S. balticum has occurred in Britain due to confusion with some forms of S. cuspidatum and S. fallax, which can exhibit some morphological characters usually used to identify S. balticum. An illustrated identification key is provided to help solve this problem. Conclusions. Sphagnum balticum is a very rare species in Britain that has undergone a decline due to habitat destruction and alteration. It is presently known to survive at only three sites, of which two are within protected areas. Microsatellites; Sphagnum cuspidatum; Sphagnum fallaxacceptedVersio

Long-term survival of bryophytes underground.: an investigation of the diaspore bank of Physcomitrium eurystomum Sendtn.

Introduction Bryophyte diaspore banks are a critical aspect of the life strategy of some species yet remain neglected and poorly understood. This study investigated the longevity in natural habitat of the diaspore bank of Physcomitrium eurystomum Sendtn., a moss species that is threatened with extinction in Europe. Methods Undisturbed soil cores of 40 cm depth were collected from Langmere, Norfolk, UK, and were split into investigated sediment layers of 1 cm depth. Dating of sediment layers was done by an analysis of radionuclides, and diaspore germination trials of each layer were carried out in a growth chamber. DNA barcoding was used to help identify plants that germinated. Key results and conclusions Viable diaspores of Physcomitrium eurystomum frequently occurred in sediment layers that were at least 100 years old and continued to occur in much lower layers that were probably several hundred years old. The long-term survival of bryophytes underground can have important implications for conservation decisions