DOI: 10.5091/plecevo.160407

Authors: Daniela del Ángel-Hernández, Lilí Martínez-Domínguez, Fernando Nicolalde-Morejón, Dennis W. Stevenson

Abstract: Background and aims – The timing of seasonal life cycle events is important for developing assessments of the extinction risk status, understanding the responses to climate change, and even evolutionary strategies. Many studies on phenology have been published about the impact of climate change; however, relatively little is known about phenological patterns in long-lived, dioecious species such as cycads. Cycad species are threatened with a high risk of extinction and require obligatory outcrossing for effective reproduction. While phenological research in cycads has been conducted in species with restricted distributions, the potential phenological variations in widely distributed species remain unaddressed. Material and methods – We analyzed phenological data of Zamia loddigesii, a cycad species with broad distribution. We selected 17 populations from Veracruz and Oaxaca, Mexico. The timing and abundance of vegetative structures were observed for 1874 plants. In total, 333 reproductive plants were found of which 216 and 117 were polliniferous and ovuliferous plants, respectively. On these plants, we recorded 589 pollen and 134 ovulate strobili. We explored the relationship between phenophases and temperature and precipitation. Key results – Our results showed a high synchrony at intrapopulation level and slight asynchrony within the distribution area for reproductive phenology. This asynchrony occurred at the northern portion. Receptivity and open pollen, at the individual level, lasted approximately two weeks, but at the species level lasted for five months with peaks of intensity between May and June. No marked seasonal pattern was found for the leaves with peaks in April and May, but leaves can be produced almost all year round. Temperature influenced only the reproductive phenological pattern. Conclusion – The vegetative phenological pattern appears to be influenced mainly by other factors including anthropogenic activities. These data allowed us to understand the reproductive dynamics that will contribute to the development of effective conservation proposals.

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DOI: 10.5091/plecevo.117464

Authors: Mohamed Hamimeche, Errol Véla, François Gillet, Riadh Moulaï

Abstract: Background and aims – In spite of their proximity to the coasts, the flora of the islands and islets of the Algerian coasts has been poorly studied. This work is the first to provide an overall view of the richness and the determinants of the Algerian island flora. Material and methods – The study is based on a compilation of original floristic data. Two classifications of 30 islands and islets were derived from PCA and HCPC performed on the species occurrence matrix and on a matrix of flora descriptors including species richness, functional traits (life form, seed dispersal, pollination), and biogeographic range. We performed an RDA to explain the variation in flora characteristics by a set of physiographic (longitude, latitude, elevation, area, isolation, steepness index, and area/perimeter ratio) and biotic (seabird density and human presence) variables. Key results – The floristic inventory encompassed a total richness of 295 vascular plant taxa (including subspecies and varieties) on the 30 studied sites. Five main groups of islands and islets can be distinguished based on vegetation composition and three from flora descriptors. RDA model selection revealed that the combination of four variables (seabird density, area, latitude, and longitude) explained 26.6% of the variation in flora characteristics. Taken alone, the density of yellow-legged gull colonies and the island area were the main drivers of this variation. Results showed that floristic richness was associated with larger island area and higher seabird density, the importance of some plant functional traits, such as zoochory and entomogamy, and with a higher proportion of Eurasian holarctic species. Conclusion – In the context of island flora conservation, some of these small islands of Algeria can be considered as “modern refuges” from human pressures, and this is particularly important in the context of Mediterranean ecosystems characterised by a quasi-permanent human impact in various habitats. Two new important plant areas (IPAs) for Algeria are proposed following the results of these floristic inventories.

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DOI: 10.5091/plecevo.95929

Authors: Federico Selvi, Giandiego Campetella, Roberto Canullo, Stefano Chelli, Gianniantonio Domina, Emmanuele Farris, Cristina Gasperini, Leonardo Rosati, Camilla Wellstein, Elisa Carrari

Abstract: Background and aims – Forests are among the most threatened ecosystems worldwide, and endemic plants are often a vulnerable component of the flora of a given territory. So far, however, understory forest endemics of southern Europe have received little attention and are poorly known for several aspects. Material and methods – We developed the first list of native vascular plants that are restricted to Italian forests. Available information on taxonomy, regional distribution, ecology, biology, functional traits, and conservation status was collected for each taxon, allowing to identify major knowledge gaps and calculate baseline statistics. Key results – The list includes 134 taxa, most of which are linked to closed-canopy forest habitats, while the others are also found in margins and gaps. The forest and non-forest Italian endemic flora differed in terms of taxonomic and life-form distribution. The rate and density of forest endemism increased with decreasing latitude and were highest in Sicily, Calabria, and Basilicata, where paleoendemic mono- or oligotypic genera also occur. Endemic phanerophytes were especially numerous on islands. Beech and deciduous oak forests were the most important habitats, but hygrophilous woodlands also host numerous endemics. Overall, the ecology, biology, and functional traits of the forest endemic taxa are still poorly known. The ratio diploids/polyploids was highest in the south and on the islands. Almost 24% of the taxa were assessed as “Critically Endangered”, “Endangered”, or “Vulnerable”, and 24% were categorized as “Data Deficient”, based on the IUCN system. Increasing frequency and intensity of fires was the most frequent threat. Conclusions – This work can contribute to implement the European forest plant species list and serve as a basis for further research on a unique biological heritage of the continent. However, more knowledge about these globally rare taxa is needed, to support their conservation in changing forest landscapes.

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DOI: 10.5091/plecevo.2020.1682

Authors: Colleen Friday, John Scasta

Abstract: Background and aims – Native American reservations in the United States provide biodiversity critical for conservation and ecosystem functions. Unfortunately, botanical inventories are less common for reservations than other land jurisdictions. Such ecological importance and needs are apparent for the Wind River Indian Reservation (WRIR), the 7th largest reservation in the US (>890,000 ha) that is shared by the Eastern Shoshone and Northern Arapaho.Material and methods – A botanical study for two WRIR high-elevation basins (Saint Lawrence Basin (SLB) and Paradise Basin (PB)) to (1) reconcile a 1960 plant list, and (2) quantify plant communities ecologically was conducted. In 2017, 106 monitoring sites were established to quantify species presence. Across basins, 231 total vascular plant taxa (221 to species and 10 to genus) were identified, or > 3× more plant species than noted in the 1960 list. In SLB, 222 plant taxa (213 to species and 9 to genus) were identified and in PB 98 plant taxa (90 to species and 8 to genus) were identified. In 2018, sites were re-sampled to quantify species abundance, soil pH, organic matter, soil nutrients, CEC, salts, and texture. Key results – Slope and elevation explained species distributions in the topography ordination and soil organic matter, pH, texture, P, and K explained species distributions in the soil ordination. Eleven exotic species, and one rare endemic species were documented with implications for empowering tribal management. Using a classification approach followed by an indicator species analysis and fidelity (Phi) assessment, we identified 14 unique plant communities and related these to 6 alliances and 7 associations across 6 macrogroups from the US National Vegetation Classification database. These indicator species of communities included sedges (Carex aquatilus), grasses (Pseudoroegneria spicata, Elymus elymoides, Achnatherum lettermanii, Elymus trachycaulus subsp. trachycaulus, Poa glauca subsp. rupicola), forbs (Polygonum bistortoides, Balsamorhiza incana, Castilleja flava), shrubs (Artemisia tridentata, Betula glandulosa, Dasiphora fruticosa subsp. floribunda) and trees (Pinus contorta).Conclusion – The plant taxa, plant communities, and ecological drivers documented in this study will enhance tribal and federal monitoring of these high-elevation WRIR basins.

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