Empirical realised niche models for British coastal plant species

Coastal environments host plant taxa adapted to a wide range of salinity conditions. Salinity, along with other abiotic variables, constrains the distribution of coastal plants in predictable ways, with relatively few taxa adapted to the most saline conditions. However, few attempts have been made to quantify these relationships to create niche models for coastal plants. Quantification of the effects of salinity, and other abiotic variables, on coastal plants is essential to predict the responses of coastal ecosystems to external drivers such as sea level rise. We constructed niche models for 132 coastal plant taxa in Great Britain based on eight abiotic variables. Paired measurements of vegetation composition and abiotic variables are rare in coastal habitats so four of the variables were defined using community mean values for Ellenberg indicators, i.e. scores assigned according to the typical alkalinity, fertility, moisture availability and salinity of sites where a species occurs. The remaining variables were the canopy height, annual precipitation, and maximum and minimum temperatures. Salinity and moisture indicator scores were significant terms in over 80 % of models, suggesting the distributions of most coastal species are at least partly determined by these variables. When the models were used to predict species occurrence against an independent dataset 64 % of models gave moderate to good predictions of species occurrence. This indicates that most models had successfully captured the key determinants of the niche. The models could potentially be applied to predict changes to habitats and species-dependent ecosystem services in response to rising sea levels

The role of microtopography in the assessment of ecological condition on lowland raised bogs of conservation importance

The principal aim of this thesis is to investigate relationships between the hydrology, ecology and vegetative microtopography of lowland raised mires, using data collected from two sites in Cumbria: Bolton Fell Moss and Walton Moss. The sites were chosen for study as they provided a contrast between the almost pristine condition of Walton Moss and the heavily modified Bolton Fell Moss, which has a long history of mechanised peat cutting. The study uses data collected from the two sites over a four year monitoring period between 2004 and 2007. Depth to water table data was obtained from five dipwell transects, complemented by seven automated loggers to provide temporal variation. A series of corresponding vegetation quadrats were established to inform ecological condition. The applicability of using remotely sensed LiDAR data to determine bog hydro-ecological condition was considered. The variation in LiDAR spot heights in 20m2 plots associated with the dipwells was used to provide an indicator of topographic variability at that location. Topographic variability was also directly measured by measuring spot heights across a corresponding 2m2 plot using differential GPS surveying equipment

From Space to Eye Lens: Monitoring protected sites with Earth Observation: Combining field data with CASI and Sentinel imagery

This report details work undertaken, led by Manchester Metropolitan University in collaboration with Natural England. The aim of this research was to investigate the potential of Earth observation (EO) data to contribute towards the monitoring of protected sites at the landscape scale, to understand resilience, and to map natural capital assets. This was achieved through the integration of field vegetation survey data with Sentinel-2 and CASI imagery to map ecosystem attributes, particularly ecological gradients and species and plant communities. Two contrasting areas in the north-west of England were used as case studies: Ainsdale National Nature Reserve (NNR) sand dunes and the Forest of Bowland blanket bog. Based on the outcomes of this research, a number of recommendations for future study and implementation have been outlined

Temporal changes of vascular plant diversity in response to tree dieback in a mediterranean lowland forest

Palo Laziale wood is a small biotope of about 129 ha situated along the north coast of Rome. It is one of the last remaining patches of an ancient lowland floodplain forest that once covered the coastal area of the Lazio region. It contains several habitats and species of high conservation interest which has been included in the Natura2000 network. The forest suffered an impressive dieback event in 2003, coinciding with a particularly hot and dry summer. In the framework of an ecological restoration project (LIFE PRIMED LIFE17 NAT/GR/000511), a preliminary assessment of the biotic and abiotic components of the ecosystem was carried out, including a floristic analysis. This analysis was compared with that conducted in 1990 to assess whether there was any change in the species composition also following the forest dieback. Comparisons between biological forms, chorotypes and the Ellenberg indicators were also made in the analysis. The total flora of the site increased from 462 to 490 species. Moreover, there has been a turnover of species with the disappearance of some grassland and halophytic species and the appearance of allochthonous/ruderal and freshwater habitat species. Despite this, the flora remained unchanged in ecological terms, demonstrating a certain resilience of the plant species, confirming this approach to identify declining processes and support ecosystem-based restoration actions elsewhere

Ecological conditions of the vegetation and vascular plant species distribution in the selected forest seepage spring area (NE Poland) based on a fine-scale assessment

The existence and functioning of spring ecosystems is determined by groundwater seepage or outflow. The water seeping through the ground surface triggers off the headward and deep erosion processes, which results in the channelled shape of the lowland rheocrenic springs. Spring areas significantly contribute to the floristic, phytocoenotic and landscape diversity. The literature on the vegetation cover of lowland spring ecosystems is scarce. Most papers refer to the identification of their flora and plant communities, less frequently – the relationships between habitat conditions and vegetation. The studies indicate that pH and moisture content are the main factors determining the composition and species diversity of ecosystems supplied by groundwater. My study presents a detailed geobotanical analysis performed on one forested spring area (together with an adjacent area) of 0.378 ha, which was divided into 945 study plots – squares with an area of 4 m2. Three zones were distinguished in the studied spring area: the bottom with a specific mosaic pattern caused by the presence of streams, water seepage sites and mineral islands, the steep slope and the surrounding area. A detailed map of habitats and the actual vegetation was prepared. A list of vascular plant species was compiled for each study plot, based on which maps with the distribution of mean Ellenberg’s indicator values were created. Statistically significant differences in the variance of Ellenberg’s indicator values between the distinguished zones were demonstrated (ANOVA), and the correlations between the ecological indicators within a given zone were calculated. CCA analysis of plant communities and the distinguished zones revealed that the occurrence of e.g. Carici remotae-Fraxinetum and non-forest plant communities of wet and moist habitats is associated with the bottom of the niche characterised by a high value of Ellenberg’s moisture indicator F. Whereas the Acer platanoides-Tilia cordata community and the Tilio-Carpinetum corydaletosum association develop on the slope with high values of the temperature indicator T. Furthermore, the CCA analysis performed on the plant species and the distinguished zones confirmed the above results. It has been shown that the species composition and the distribution of plant species and plant communities in the study area are mainly determined by soil moisture content, but also by light and temperature

Impacts of Land Abandonment on Vegetation: Successional Pathways in European Habitats

Changes in traditional agricultural systems in Europe in recent decades have led to widespread abandonment and colonization of various habitats by shrubs and trees. We combined several vegetation databases to test whether patterns of changes in plant diversity after land abandonment in different habitats followed similar pathways. The impacts of land abandonment and subsequent woody colonization on vegetation composition and plant traits were studied in five semi-natural open habitats and two arable habitats in six regions of Europe. For each habitat, vegetation surveys were carried out in different stages of succession using either permanent or non-permanent plots. Consecutive stages of succession were defined on a physiognomic basis from initial open stages to late woody stages. Changes in vegetation composition, species richness, numbers of species on Red Lists, plant strategy types, Ellenberg indicator values of the vegetation, Grime CSR strategy types and seven ecological traits were assessed for each stage of the successional pathway. Abandonment of agro-pastoral land-use and subsequent woody colonization were associated with changes in floristic composition. Plant richness varied according to the different habitats and stages of succession, but semi-natural habitats differed from arable fields in several ecological traits and vegetation responses. Nevertheless, succession occurred along broadly predictable pathways. Vegetation in abandoned arable fields was characterized by a decreasing importance of R-strategists, annuals, seed plants with overwintering green leaves, insect-pollinated plants with hemi-rosette morphology and plants thriving in nutrient-rich conditions, but an increase in species considered as endangered according to the Red Lists. Conversely, changes in plant traits with succession within the initially-open semi-natural habitats showed an increase in plants thriving in nutrient-rich conditions, stress-tolerant plants and plants with sexual and vegetative reproduction, but a sharp decrease in protected species. In conclusion, our study showed a set of similarities in responses of the vegetation in plant traits after land abandonment, but we also highlighted differences between arable fields and semi-natural habitats, emphasizing the importance of land-use legacy

Using Worldview-2 satellite imagery to detect indicators of high species diversity in grasslands

The high small-scale diversity of plant species in semi-natural grasslands can be seen as a function of environmental conditions and land use history. This study explores the potential of using Worldview-2 spectral imagery and accessible GIS data to identify a set of vegetation characteristics known to influence biodiversity in semi-natural grasslands. Field sampling was done in 52 grassland sites, with presence and frequency of plant species and vegetation structural composition recorded in 4 m x 4 m plots. Plant species data were used to calculate overall species richness, grassland specialist richness, grassland generalist richness and Ellenberg indicator values for reaction (R), nutrients (N), soil moisture (M) and light (L). Generalized Additive models (GAM) were constructed to explain observed vegetation variables, predicted by mean values and standard deviations of WordView-2 satellite spectral reflectance and GIS data of grassland habitat area, soil type and land use history. The study was carried out on two spatial scales: 4m x 4m plots and grassland sites (0.25 ha - 14 ha). The results show that high resolution satellite imagery has potential of characterizing species diversity indirectly by the habitat productivity and heterogeneity. Grassland habitats with high small-scale species diversity had relatively low spectral heterogeneity. It was difficult to measure species diversity on a fine spatial scale using only remote sensing variables. Grassland management history is a very good predictor of species composition and diversity, especially for specialized grassland species. Ellenberg values for soil moisture (M) and nutrients (N) were successfully modelled using remote sensing data. In grasslands where the species diversity is largely driven by environmental gradients like nutrients or soil moisture, ecological indicators can be used as an alternative to species diversity to assess habitat quality

Basaltic outcrops as centers of diversity for xerothermic plants in the Sudetes Mountains (Central Europe)

Rock outcrops have promoted a high level of species diversity and provided a stable mi-croclimate for long time periods. The present study is devoted to plant diversity of natural Quater-nary outcrops of basaltic rocks. Chorological and ecological investigations were carried out at 35 such outcrops, located within five physiogeographic units of the Sudetes Mountains. The focus was on 120 xerothermic taxa of vascular plants: 62 strictly xerothermic (steppe) taxa of the Festuco valesi-acae-Brometea erecti class, and 58 thermophilous taxa representing classes Trifolio medii-Geranietea sanguinei and Quercetea pubescentis. Limited geographical ranges of these plants are manifested by variable frequency of their occurrence. Species distribution is determined by natural factors, like surface area of the outcrop, the type of basaltic rock and the type of plant communities developed. Basaltic outcrops in the Sudetes meet the criterion of habitat islands (inselbergs), serve as regional centers of vascular flora, and are refugia for marginal populations of relict species

Modelling and mapping of exceedance of critical loads and critical levels for acidification and eutrophication in the UK 2013-2016. Final report

This report covers the work of the original contract (2013-15) and the following one-year extension (2015-16). The overall purpose of this project was to maintain, and where appropriate update, the UK critical loads database, and to provide estimates of critical load and critical level exceedance based on current pollutant deposition or concentrations, and scenarios for the future. The exceedance results were used to inform policy makers on the areas of sensitive habitats and designated sites potentially at risk from air pollution and were updated annually to provide a UK indicator of the impacts of air pollution on ecosystems. The project also supported the UK National Focal Centre (NFC) for critical loads modelling and mapping. The 1-year extension to this contract additionally included the biodiversity modelling required to enable the UK NFC to begin work in preparation for responding to the 2015-17 “Call for Data” under the UNECE Convention on Long-Range Transboundary Air Pollution (CLRTAP)