Mobile dune fixation by a fast-growing clonal plant: a full life-cycle analysis

Desertification is a global environmental problem, and arid dunes with sparse vegetation are especially vulnerable to desertification. One way to combat desertification is to increase vegetation cover by planting plant species that can realize fast population expansion, even in harsh environments. To evaluate the success of planted species and provide guidance for selecting proper species to stabilize active dunes, demographic studies in natural habitats are essential. We studied the life history traits and population dynamics of a dominant clonal shrub Hedysarum laeve in Inner-Mongolia, northern China. Vital rates of 19057 ramets were recorded during three annual censuses (2007–2009) and used to parameterize Integral Projection Models to analyse population dynamics. The life history of H. laeve was characterized by high ramet turnover and population recruitment entirely depended on clonal propagation. Stochastic population growth rate was 1.32, suggesting that the populations were experiencing rapid expansion. Elasticity analysis revealed that clonal propagation was the key contributor to population growth. The capacity of high clonal propagation and rapid population expansion in mobile dunes makes H. laeve a suitable species to combat desertification. Species with similar life-history traits to H. laeve are likely to offer good opportunities for stabilizing active dunes in arid inland ecosystems

Rapid post-fire re-assembly of species-rich bryophyte communities in Afroalpine heathlands

Questions In some fire-prone ecosystems, bryophytes play a crucial role by providing the surface fuel that controls the fire return interval. Afroalpine heathlands are such an ecosystem, yet almost nothing is known about the bryophytes in this system. We do not know the level of species richness, or if there is a successive accumulation of species over time, or if some species are adapted to specific phases along the successional gradient, for example early-successional species sensitive to competition. Location Afroalpine heathlands in Ethiopia. Methods We made an inventory of all bryophytes in 48 plots of 5 m × 5 m, distributed along a chronosequence from 1 to 25 years post fire. The heathlands are located between 3500 m and 3800 m a.s.l. and are managed by traditional pasture burning with fire intervals of 8–20 years. Results We found in total 111 taxa of bryophytes. Post-fire mortality was almost 100%. The youngest plots had only a few cosmopolitan species often found after fire. Initially, species richness increased monotonically while starting to level off around 15 years after fire, when many plots had around 30 species and a high cover of Breutelia diffracta, which is a key ground-living species, important as surface fuel. Most species were found with sporophytes, a pattern even stronger for the most frequent species. Conclusions Interestingly, bryophyte diversity is already remarkably high by only 15 years after total eradication. The relatively slow accumulation of species in the first years after fire suggests that dispersal in space, and not time, is the major mechanism by which sites regain their diversity (i.e. spore banks play a smaller role than colonization of wind-borne spores). This indicates that the high species richness is built up through colonization from surrounding heathlands, and perhaps also from higher-altitude alpine grasslands and lower-altitude forests, and that the bryophyte diversity in this system is maintained by the traditional fire and grazing management

A miniature world in decline: European Red List of Mosses, Liverworts and Hornworts

AimThis Red List is a summary of the conservation status of the European species of mosses, liverworts and hornworts, collectively known as bryophytes, evaluated according to IUCN’s Guidelines for Application of IUCN Red List Criteria at Regional Level. It provides the first comprehensive, region-wide assessment of bryophytes and it identifies those species that are threatened with extinction at a European level, so that appropriate policy measures and conservation actions, based on the best available evidence, can be taken to improve their status.ScopeAll bryophytes native to or naturalised in Europe (a total of 1,817 species), have been included in this Red List. In Europe, 1,796 species were assessed, with the remaining 21 species considered Not Applicable (NA). For the EU 28, 1,728 species were assessed, with a remaining 20 species considered NA and 69 species considered Not Evaluated (NE). The geographical scope is continentwide, extending from Iceland in the west to the Urals in the east, and from Franz Josef Land in the north to theCanary Islands in the south. The Caucasus region is not included. Red List assessments were made at two regional levels: for geographical Europe and for the 28 Member States of the European Union.ResultsOverall, 22.5% of European bryophyte species assessed in this study are considered threatened in Europe, with two species classified as Extinct and six assessed as Regionally Extinct (RE). A further 9.6% (173 species) are considered Near Threatened and 63.5% (1,140 species) are assessed as Least Concern. For 93 species (5.3%), there was insufficient information available to be able to evaluate their risk of extinction and thus they were classified as Data Deficient (DD). The main threats identified were natural system modifications (i.e., dam construction, increases in fire frequency/intensity, and water management/use), climate change (mainly increasing frequency of droughts and temperature extremes), agriculture (including pollution from agricultural effluents) and aquaculture.RecommendationsPolicy measures• Use the European Red List as the scientific basis to inform regional/national lists of rare and threatened species and to identify priorities for conservation action in addition to the requirements of the Habitats Directive, thereby highlighting the conservation status of bryophytes at the regional/local level.• Use the European Red List to support the integration of conservation policy with the Common Agricultural Policy (CAP) and other national and international policies. For example, CAP Strategic Plans should include biodiversity recovery commitments that could anticipate, among others, the creation of Important Bryophyte Areas. An increased involvement of national environmental agencies in the preparation of these strategic plans, and more broadly in ongoing discussions on the Future CAP Green Architecture, would likely also ensure the design of conservation measures better tailored to conserve bryophytes in agricultural landscapes.• Update the European Red List every decade to ensure that the data remains current and relevant.• Develop Key Biodiversity Areas for bryophytes in Europe with a view to ensuring adequate site-based protection for bryophytes.Research and monitoring• Use the European Red List as a basis for future targeted fieldwork on possibly extinct and understudied species.• Establish a monitoring programme for targeted species (for example, threatened species and/or arable bryophytes).• Use the European Red List to obtain funding for research into the biology and ecology of key targeted species.Action on the ground• Use the European Red List as evidence to support multi-scale conservation initiatives, including designation of protected areas, reform of agricultural practices and land management, habitat restoration and rewilding, and pollution reduction measures.• Use the European Red List as a tool to target species that would benefit the most from the widespread implementation of the solutions offered by the 1991 Nitrates Directive (Council Directive 91/676/EEC), including the application of correct amounts of nutrients for each crop, only in periods of crop growth under suitable climatic conditions and never during periods of heavy rainfall or on frozen ground, and the creation of buffer zones to protect waters from run-off from the application of fertilizers.Ex situ conservation• Undertake ex situ conservation of species of conservation concern in botanic gardens and spore and gene banks, with a view to reintroduction where appropriate.</p

Life forms and life strategies in Nanocyperion communities from the Netherlands Frisian Islands

Nanocyperion communities (s.l.) are considered here as “warp-and-woof” communities; the Nanocyperion components are described separately as synusiae. On the Netherlands Frisian Islands, four main synusiae have been recognized. Raunkiaer life form spectra show few differences between the communities. Life strategy spectra of the Nanocyperion synusiae, based on systems for phanerogams (modified after Bakker 1966) and bryophytes, yield the clearest patterns. A comparison of the ecology of the communities and an interpretation of the spectra in terms of avoidance of stress or competition suggest that inundations and standing crop of the communities are the main factors determining the distribution of the synusiae. Winter inundations overrule the influence of differences in productivity level, which becomes prominent in drier situations

Nieuwe vondsten van Bryum torquescens (zonneknikmos) in Zuid-Limburg

In the Netherlands Bryum torquescens is known mainly from calcareous soils and limestone in the southernmost part of the country. Most records date from the 19th century. The species was rediscovered in chalk grasslands in this same area (1995 and 2002) and in adjacent Belgium (1987)

Recent developments in bryophyte population ecology

Bryophytes abound in a wide variety of habitats, and despite their low stature play a significant role in many ecosystems. Earlier views of bryophytes as being ‘evolutionary failures’ are being questioned since the discovery of high genetic variability in those species and populations which have been studied. At the same time, there is growing evidence that in many taxa the maintenance of populations is almost completely dependent on asexual propagation; sexual reproduction may result in an enormous spore output, but establishment from spores in the field seems to be very difficult. The remarkably rapid fine-scale dynamics found in many bryophyte populations may play a role in the maintenance of genetical variability; it may also partly determine community diversity

Experimental ramet aggregation in the clonal plant Agrostis stolonifera reduces its competitive ability

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