The MOVECLIM - AZORES project: Bryophytes from Pico Island along an elevation gradient.

Background: In September 2012, a comprehensive survey of Pico Island was conducted along an elevational transect, starting at Manhenha (10 m a.s.l.) and culminating at the Pico Mountain caldera (2200 m a.s.l.). The primary objective was to systematically inventory the bryophytes inhabiting the best-preserved areas of native vegetation environments. Twelve sites were selected, each spaced at 200 m elevation intervals. Within each site, two 10 m x 10 m plots were established in close proximity (10-15 m apart). Within these plots, three 2 m x 2 m quadrats were randomly selected and sampled for bryophytes using microplots measuring 10 cm x 5 cm, which were then collected into paper bags. Six substrates were surveyed in each quadrat: rock, soil, humus, organic matter, tree bark and leaves/fronds. Three replicates were obtained from all substrates available and colonised by bryophytes, resulting in a maximum of 18 microplots per quadrat, 54 microplots per plot, 108 microplots per site, and a total of 1296 microplots across the 12 sites on Pico Island. New information: Two-thirds of the maximum expected number of microplots (n = 878; 67.75%) were successfully collected, yielding a total of 4896 specimens. The vast majority (n = 4869) were identified at the species/subspecies level. The study identified a total of 70 moss and 71 liverwort species or subspecies. Elevation levels between 600-1000 m a.s.l., particularly in the native forest plots, exhibited both a higher number of microplots and greater species richness. This research significantly enhanced our understanding of Azorean bryophyte diversity and distribution, contributing valuable insights at both local and regional scales. Notably, two new taxa for the Azores were documented during the MOVECLIM study, namely the pleurocarpous mosses Antitrichiacurtipendula and Isotheciuminterludens.

Biota of coastal wetlands of Praia da Vitória (Terceira Island, Azores): Part 2 - Bryophytes.

BACKGROUND: During the LIFE-CWR project "Ecological Restoration and Conservation of Praia da Vitória Coastal Wet Green Infrastructures", there was the opportunity to undertake a systematic record of bryophytes at Paul da Praia da Vitória (PPV), Paul do Belo Jardim (PBJ) and Paul da Pedreira do Cabo da Praia (PPCP), three coastal wetland areas of Praia da Vitória (Terceira, Azores, Portugal). The objective of the study was to perform a biodiversity assessment, comparing the three sites at two different moments, before and after the implementation of several conservation measures. This project also contributed to improve the knowledge of Azorean bryophyte diversity at both local and regional scales, including the recording of two new taxa for the Azores and three new taxa for Terceira Island. NEW INFORMATION: This paper reports the results of the first extensive survey of bryophyes of the three coastal wetland areas of Praia da Vitória (Terceira Island, Azores, Portugal). The identification of a total of 504 samples, 240 collected in 2013 and 2016 (before the LIFE-CWR intervention) and 265 in 2017 and 2018 (after the intervention), resulted in a list of 58 species of bryophytes (one hornwort, eight liverworts and 48 mosses). These include two new records for the Azores (Bryum klinggraeffii, Ptychostomum bornholmense), three new records for Terceira Island (Bryum tenuisetum, Dicranella howei, Trichostomum crispulum) and at least 15 new records for the municipality of Praia da Vitória (e.g., Cephaloziella hampeana). Some species that had not been recorded on the island since 1937 (e.g., Fissidens crispus) were collected during this study, as well as a Macaronesian endemic liverwort (Radula wichurae), an Iberian-Macaronesian liverwort (Frullania azorica) and a moss species with European distribution (Ptychomitrium nigrescens). From the recorded species, only one moss (Leptophascum leptophyllum), of subtropical origin, is considered invasive in Europe.

Spatial modeling of factor analysis scores: the case of heavy metal biomonitoring in mainland Portugal.

The use of mosses as biomonitors operates as an indicator of their concentration in the environment, becoming a methodology which provides a significant interpretation in terms of environmental quality. The different types of pollution are variables that can not be measured directly in the environment - latent variables. Therefore, we propose the use of factor analysis to estimate these variables in order to use them for spatial modelling. On the contrary, the main aim of the commonly used principal components analysis method is to explain the variability of observed variables and it does not permit to explicitly identify the different types of environmental contamination. We propose to model the concentration of each heavy metal as a linear combination of its main sources of pollution, similar to the case of multiple regression where these latent variables are identified as covariates, though these not being observed. Moreover, through the use of geostatistical methodologies, we suggest to obtain maps of predicted values for the different sources of pollution. With this, we summarize the information acquired from the concentration measurements of the various heavy metals, and make possible to easily determine the locations that suffer from a particular source of pollution.

Spatio-temporal patterns of Cu contamination in mosses using geostatistical estimation.

Several recent studies have reported temporal trends in metal contamination in mosses, but such assessments did not evaluate uncertainty in temporal changes, therefore providing weak statistical support for time comparisons. Furthermore, levels of contaminants in the environment change in both space and time, requiring space-time modelling methods for map estimation. We propose an indicator of spatial and temporal variation based on space-time estimation by indicator kriging, where uncertainty at each location is estimated from the local distribution function, thereby calculating variability intervals for comparison between several biomonitoring dates. This approach was exemplified using copper concentrations in mosses from four Portuguese surveys (1992, 1997, 2002 and 2006). Using this approach, we identified a general decrease in copper contamination, but spatial patterns were not uniform, and from the uncertainty intervals, changes could not be considered significant in the majority of the study area.

Assessment of human exposure to environmental heavy metals in soils and bryophytes of the central region of Portugal.

This study intends to identify the spatial patterns of variation for some metals and metalloids, in soils and mosses, in the central region of Portugal. The purposes were: (i) to identify relationships amongst five elements (Cu, Pb, Zn, Cr and As) in three different media (topsoil, bottom soil and bryophytes) and with some site-specific characteristics, using Multiple Correspondence Analysis; (ii) to define spatial patterns of variation for the associations identified by Multiple Correspondence Analysis using Variography and Ordinary Kriging; and (iii) to assess atmospheric deposition as a source of heavy metals to the topsoil by crossing results with the biomonitors. The results indicated relatively low metal concentrations in soils and mosses. Some metal associations and dissociations were identified. The spatial patterns of variation of bottom and topsoil are distinct. There is some evidence that different site-specific characteristics control the spatial distribution of different elements. The areas within the central region of Portugal with a higher vulnerability to metal contamination were identified.

Application of indicator kriging to the complementary use of bioindicators at three trophic levels.

The use of biological indicators is widespread in environmental monitoring, although it has long been recognised that each bioindicator is generally associated with a range of potential limitations and shortcomings. To circumvent this problem, this study adopted the complementary use of bioindicators representing different trophic levels and providing different type of information, in an innovative approach to integrate knowledge and to estimate the overall health state of ecosystems. The approach is illustrated using mercury contamination in primary producers (mosses), primary consumers (domestic pigeons and red-legged partridges) and top predators (Bonelli's eagles) in southern Portugal. Indicator kriging geostatistics was used to identify the areas where mercury concentration was higher than the median for each species, and to produce an index that combines mercury contamination across trophic levels. Spatial patterns of mercury contamination were consistent across species. The combined index provided a new level of information useful in incorporating measures of overall environmental contamination into pollution studies.

Detection of exposition risk to arsenic in Portugal assessed by air deposition in biomonitors and water contamination.

Human exposure risk to environmental arsenic is evaluated by combining drinking water and atmospheric deposition, assessed tap water analysis and a moss biomonitoring survey. Water analyses are assessed through mandatory national and European regulations for the supplying areas. Moss concentrations were determined as part of a biomonitoring survey performed at a national level in 2002. For each of the parameters, continuous maps of indicator values were determined applying geostatistical methods, namely indicator kriging. The exposure risk of human populations was determined afterwards combining the indicator values of water and biomonitoring values. The identified regions of accumulated water and atmospheric exposure are in the inland north and central areas of the country.

Specialized cheating of the ectomycorrhizal symbiosis by an epiparasitic liverwort.

Many non-photosynthetic vascular plants in 10 diverse families obtain all of their carbon from fungi, but in most cases the fungi and the ultimate sources of carbon are unknown. In a few cases, such plants have been shown to be epiparasitic because they obtain carbon from neighbouring green plants through shared mycorrhizal fungi. In all such cases, the epiparasitic plants have been found to specialize upon narrow lineages of ecto- or arbuscular mycorrhizal fungi. Here we show that a non-vascular plant, the non-photosynthetic liverwort Cryptothallus mirabilis, is epiparasitic and is specialized on Tulasnella species that form ectomycorrhizae with surrounding trees at four locations in England, France and Portugal. By using microcosm experiments we show that the interaction with Tulasnella is necessary for growth of Cryptothallus, and by using labelling experiments we show that (14)CO(2) provided to birch seedlings is transferred to Cryptothallus by Tulasnella. This is one of the first documented cases of epiparasitism by a non-vascular plant and of ectomycorrhizal formation by Tulasnella. These results broaden the emerging association between epiparasitism and mycorrhizal specialization into a new class of plants and a new order of fungi.