Myrrhido-Adenostyletum, endemična asocijacija jugozapadnih Alpa

Autor opisuje novu endemičnu asocijaciju Myrrhido-Adenostyletum iz sveze Adenostylion alliariae. To je zajednica visokih zeleni rasprostranjena u jugozapadnim Alpama u dolini rijeke Ubaye u subalpskom pojasu između 1800 i 2000 m na staništima gdje se nakuplja mnogo snijega. Zajednica je izgrađena gotovo isključivo od hemikriptofitskih biljaka. Floristički sastav vidi se na priloženoj fitosociološkoj tabeli

Robert Harding Whittaker and the Individualistic Hypothesis

No abstract available

Low impact of climate change on subalpine grasslands in the Swiss Northern Alps?

While phenological shifts and migration of isolated species under climate change have already been observed on alpine summits, very few studies have focused on community composition changes in subalpine grasslands. Here we use permanent plots monitored since 1954 and precisely located phytosociological censuses from 1970 to study compositional changes of subalpine grasslands in two distinct regions of the Swiss Northern Alps. In both areas, warming trends during the monitoring period were associated with changes in land management (abandonment of goat and sheep pasturing or grazing replaced by mowing). Old and recent inventories were compared with correspondence analyses (CA). Ecological indicator values, community-affinities and biological traits of the species were used to infer the factors responsible for triggering the observed changes. In both regions, subalpine grasslands were stable with smaller changes than have previously been observed in alpine environments. Only a few species appeared or disappeared and changes were generally limited to increasing or decreasing frequency and cover of certain taxa. At one site, grazing abandonment favoured fallow species. Some of these species were located at their upper altitudinal distribution limits and may have spread because of rising temperatures. In both areas, declining species were predominantly alpine and low growing species; their decline was probably due to increased competition (e.g., shade) with more vigorous subalpine taxa no longer limited by grazing. We conclude that vegetation communities can respond rapidly to warming as long as colonisation is facilitated by available space or structural change. In the subalpine grasslands studied, changes were mainly driven by land management. These communities have a dense vegetation cover and newly arriving herbaceous species preferring warmer conditions may take some time to establish themselves. However, climate disturbances, such as exceptional drought, may accelerate community changes by opening gaps for new species

CWRML: representing crop wild relative conservation and use data in XML

Background Crop wild relatives are wild species that are closely related to crops. They are valuable as potential gene donors for crop improvement and may help to ensure food security for the future. However, they are becoming increasingly threatened in the wild and are inadequately conserved, both in situ and ex situ. Information about the conservation status and utilisation potential of crop wild relatives is diverse and dispersed, and no single agreed standard exists for representing such information; yet, this information is vital to ensure these species are effectively conserved and utilised. The European Community-funded project, European Crop Wild Relative Diversity Assessment and Conservation Forum, determined the minimum information requirements for the conservation and utilisation of crop wild relatives and created the Crop Wild Relative Information System, incorporating an eXtensible Markup Language (XML) schema to aid data sharing and exchange. Results Crop Wild Relative Markup Language (CWRML) was developed to represent the data necessary for crop wild relative conservation and ensure that they can be effectively utilised for crop improvement. The schema partitions data into taxon-, site-, and population-specific elements, to allow for integration with other more general conservation biology schemata which may emerge as accepted standards in the future. These elements are composed of sub-elements, which are structured in order to facilitate the use of the schema in a variety of crop wild relative conservation and use contexts. Pre-existing standards for data representation in conservation biology were reviewed and incorporated into the schema as restrictions on element data contents, where appropriate. Conclusion CWRML provides a flexible data communication format for representing in situ and ex situ conservation status of individual taxa as well as their utilisation potential. The development of the schema highlights a number of instances where additional standards-development may be valuable, particularly with regard to the representation of population-specific data and utilisation potential. As crop wild relatives are intrinsically no different to other wild plant species there is potential for the inclusion of CWRML data elements in the emerging standards for representation of biodiversity data

Notes on phytosociology of Juniperus excelsa in Macedonia (southern Balkan Peninsula)

Juniperus excelsa is an East Mediterranean species found also in marginal, sub-mediterranean regions of the southern part of the Balkan Peninsula. It prefers shallow soils in the warmest habitats of the zone of thermophilous deciduous forests. In the past the rank of alliance and the name of Juniperion excelsae-foetidissimae have been suggested for the vegetation dominated by Juniperus excelsa in the Balkan Peninsula. In this paper we present the valid description of the alliance in accordance with the International Code of Phytosociological Nomenclature. The validation of the Juniperion excelsae-foetidissimae required description of a new association - the Querco trojanae-Juniperetum excelsae. The Juniperion excelsae-foetidissimae is classified within the order of Quercetalia pubescentis Klika 1933 (the Quercetea pubescentis Doing-Kraft ex Scamoni et Passarge 1959)

Drought mildly reduces plant dominance in a temperate prairie ecosystem across years

1. Shifts in dominance and species reordering can occur in response to global change. However, it is not clear how altered precipitation and disturbance regimes interact to affect species composition and dominance. 2. We explored community‐level diversity and compositional similarity responses, both across and within years, to a manipulated precipitation gradient and annual clipping in a mixed‐grass prairie in Oklahoma, USA. We imposed seven precipitation treatments (five water exclusion levels [−20%, −40%, −60%, −80%, and −100%], water addition [+50%], and control [0% change in precipitation]) year‐round from 2016 to 2018 using fixed interception shelters. These treatments were crossed with annual clipping to mimic hay harvest. 3. We found that community‐level responses were influenced by precipitation across time. For instance, plant evenness was enhanced by extreme drought treatments, while plant richness was marginally promoted under increased precipitation. 4. Clipping promoted species gain resulting in greater richness within each experimental year. Across years, clipping effects further reduced the precipitation effects on community‐level responses (richness and evenness) at both extreme drought and added precipitation treatments. 5. Synthesis: Our results highlight the importance of studying interactive drivers of change both within versus across time. For instance, clipping attenuated community‐level responses to a gradient in precipitation, suggesting that management could buffer community‐level responses to drought. However, precipitation effects were mild and likely to accentuate over time to produce further community change.Open Access fees paid for in whole or in part by the University of Oklahoma Libraries. This study was financially supported by NSF Office of Experimental Program to Stimulate Competitive Research (OIA‐1301789) and Office of the Vice President for Research, University of Oklahoma.Ye

Late Little Ice Age palaeoenvironmental records from the Anzali and Amirkola Lagoons (south Caspian Sea): Vegetation and sea level changes

This is a postprint version of the article. The official published article can be found from the link below - Copyright @ 2011 Elsevier Ltd.Two internationally important Ramsar lagoons on the south coast of the Caspian Sea (CS) have been studied by palynology on short sediment cores for palaeoenvironmental and palaeoclimatic investigations. The sites lie within a small area of very high precipitation in a region that is otherwise dry. Vegetation surveys and geomorphological investigations have been used to provide a background to a multidisciplinary interpretation of the two sequences covering the last four centuries. In the small lagoon of Amirkola, the dense alder forested wetland has been briefly disturbed by fire, followed by the expansion of rice paddies from AD1720 to 1800. On the contrary, the terrestrial vegetation reflecting the diversity of the Hyrcanian vegetation around the lagoon of Anzali remained fairly complacent over time. The dinocyst and non-pollen palynomorph assemblages, revealing changes that have occurred in water salinity and water levels, indicate a high stand during the late Little Ice Age (LIA), from AD < 1620 to 1800–1830. In Amirkola, the lagoon spit remained intact over time, whereas in Anzali it broke into barrier islands during the late LIA, which merged into a spit during the subsequent sea level drop. A high population density and infrastructure prevented renewed breaking up of the spit when sea level reached its maximum (AD1995). Similar to other sites in the region around the southern CS, these two lagoonal investigations indicate that the LIA had a higher sea level as a result of more rainfall in the drainage basin of the CS.The coring and the sedimentological analyses were funded by the Iranian National Institute for Oceanography in the framework of a research project entitled “Investigation of the Holocene sediment along the Iranian coast of Caspian Sea: central Guilan”. The radiocarbon date of core HCGL02 was funded by V. Andrieu (Europôle Méditerranéen de l'Arbois, France) and that of core HCGA04 by Brunel University