171 research outputs found
Can management intensity be more important than environmental factors? A case study along an extreme elevation gradient from central Italian cereal fields
This paper aims to assess the importance of environmental and management factors determining the weed species
composition along a strong elevation gradient. A total of 76 cereal fields (39 low input and 37 intensively managed) were
sampled along an elevation gradient in central Italy. Explanatory variables were recorded for each field to elucidate the role of
large-scale spatial trends, of site-specific abiotic environmental conditions and of field management characters. Redundancy
analysis was used to assess the relative importance of each environmental variable in explaining the variation in species
composition. Our results indicate that variation in weed species composition is strongly determined by altitude, mean annual
precipitation, mean annual temperature and also by soil characteristics. However, the level of intensification proved to be the
most influential variable. There was a significant difference in species richness and composition between low-input and
intensively managed fields. Intensification leads to considerable species loss at both lower and higher elevations. Low-input
fields had 296 species in total, while intensively managed fields had only 196
Classification of the Mediterranean lowland to submontane pine forest vegetation
Vegetation SurveyAim: Vegetation types of Mediterranean thermophilous pine forests dominated by
Pinus brutia, Pinus halepensis, Pinus pinaster and Pinus pinea were studied in various
areas. However, a comprehensive formal vegetation classification of these forests
based on a detailed data analysis has never been developed. Our aim is to provide
the first broad-scale classification of these pine forests based on a large data set of
vegetation plots.
Location: Southern Europe, North Africa, Levant, Anatolia, Crimea and the Caucasus.
Methods: We prepared a data set of European and Mediterranean pine forest vegetation
plots. We selected 7,277 plots dominated by the cold-sensitive Mediterranean
pine species Pinus brutia, Pinus halepensis, Pinus pinaster and Pinus pinea. We classified
these plots using TWINSPAN, interpreted the ecologically and biogeographically
homogeneous TWINSPAN clusters as alliances, and developed an expert system for
automatic vegetation classification at the class, order and alliance levels.
Results: We described Pinetea halepensis as a new class for the Mediterranean lowland
to submontane pine forests, included in the existing Pinetalia halepensis order,
and distinguished 12 alliances of native thermophilous pine forests, including four
newly described and three informal groups merging supposedly native stands and
old-established plantations. The main gradients in species composition reflect elevational
vegetation belts and the westâeast, and partly northâsouth, biogeographical
differences. Both temperature and precipitation seasonality co-vary with these
gradients.
Conclusions: We provide the first formal classification at the order and alliance levels
for all the Mediterranean thermophilous pine forests based on vegetation-plot data.
This classification includes traditional syntaxa, which have been critically revised,
and a new class and four new alliances. We also outline a methodological workflow that might be useful for other vegetation classification syntheses. The expert system,
which is jointly based on pine dominance and species composition, is a tool for applying
this classification in research and nature conservation survey, monitoring and
managementinfo:eu-repo/semantics/publishedVersio
Plant Diversity Changes during the Postglacial in East Asia: Insights from Forest Refugia on Halla Volcano, Jeju Island
Understanding how past climate changes affected biodiversity is a key issue in contemporary ecology and conservation biology. These diversity changes are, however, difficult to reconstruct from paleoecological sources alone, because macrofossil and pollen records do not provide complete information about species assemblages. Ecologists therefore use information from modern analogues of past communities in order to get a better understanding of past diversity changes. Here we compare plant diversity, species traits and environment between late-glacial Abies, early-Holocene Quercus, and mid-Holocene warm-temperate Carpinus forest refugia on Jeju Island, Korea in order to provide insights into postglacial changes associated with their replacement. Based on detailed study of relict communities, we propose that the late-glacial open-canopy conifer forests in southern part of Korean Peninsula were rich in vascular plants, in particular of heliophilous herbs, whose dramatic decline was caused by the early Holocene invasion of dwarf bamboo into the understory of Quercus forests, followed by mid-Holocene expansion of strongly shading trees such as maple and hornbeam. This diversity loss was partly compensated in the Carpinus forests by an increase in shade-tolerant evergreen trees, shrubs and lianas. However, the pool of these species is much smaller than that of light-demanding herbs, and hence the total species richness is lower, both locally and in the whole area of the Carpinus and Quercus forests. The strongly shading tree species dominating in the hornbeam forests have higher leaf tissue N and P concentrations and smaller leaf dry matter content, which enhances litter decomposition and nutrient cycling and in turn favored the selection of highly competitive species in the shrub layer. This further reduced available light and caused almost complete disappearance of understory herbs, including dwarf bamboo
A test on Ellenberg indicator values in the Mediterranean evergreen woods (Quercetea ilicis)
The consistency and reliability of Ellenbergâs indicator values (Eiv) as ecological descriptors of the Mediterranean evergreen vegetation ascribed to the phytosociological class Quercetea ilicis have been checked on a set of 859 phytosociological relevĂ©s Ă 699 species. Diagnostic species were identified through a Twinspan analysis and their Eiv analyzed and related to the following independent variables: (1) annual mean temperatures, (2) annual rainfall. The results provided interesting insights to disentangle the current syntaxonomical framework at the alliance level demonstrating the usefulness of ecological indicator values to test the efficiency and predictivity of the phytosociological classification
Vegetation of Europe: hierarchical floristic classification system of vascular plant, bryophyte, lichen, and algal communities
Vegetation classification consistent with the Braun-Blanquet approach is widely used in Europe for applied vegetation science, conservation planning and land management. During the long history of syntaxonomy, many concepts and names of vegetation units have been proposed, but there has been no single classification system integrating these units. Here we (1) present a comprehensive, hierarchical, syntaxonomic system of alliances, orders and classes of Braun-Blanquet syntaxonomy for vascular plant, bryophyte and lichen, and algal communities of Europe; (2) briefly characterize in ecological and geographic terms accepted syntaxonomic concepts; (3) link available synonyms to these accepted concepts; and (4) provide a list of diagnostic species for all classes. Location: European mainland, Greenland, Arctic archipelagos (including Iceland, Svalbard, Novaya Zemlya), Canary Islands, Madeira, Azores, Caucasus, Cyprus. Methods: We evaluated approximately 10 000 bibliographic sources to create a comprehensive list of previously proposed syntaxonomic units. These units were evaluated by experts for their floristic and ecological distinctness, clarity of geographic distribution and compliance with the nomenclature code. Accepted units were compiled into three systems of classes, orders and alliances (EuroVegChecklist, EVC) for communities dominated by vascular plants (EVC1), bryophytes and lichens (EVC2) and algae (EVC3). Results: EVC1 includes 109 classes, 300 orders and 1108 alliances; EVC2 includes 27 classes, 53 orders and 137 alliances, and EVC3 includes 13 classes, 24 orders and 53 alliances. In total 13 448 taxa were assigned as indicator species to classes of EVC1, 2087 to classes of EVC2 and 368 to classes of EVC3. Accepted syntaxonomic concepts are summarized in a series of appendices, and detailed information on each is accessible through the software tool EuroVegBrowser. Conclusions: This paper features the first comprehensive and critical account of European syntaxa and synthesizes more than 100 yr of classification effort by European phytosociologists. It aims to document and stabilize the concepts and nomenclature of syntaxa for practical uses, such as calibration of habitat classification used by the European Union, standardization of terminology for environmental assessment, management and conservation of nature areas, landscape planning and education. The presented classification systems provide a baseline for future development and revision of European syntaxonomy.info:eu-repo/semantics/publishedVersio
Classification of mesic grasslands and their transitions of South Transdanubia (Hungary)
RelevĂ©s from meadows and pastures of South Transdanubia (Hungary) are evaluated by clustering and ordination methods. The relevĂ© selection focused on the Arrhenatheretalia order but its transitions towards other types were also included. The groups of relevĂ©s are delimited and described according to differential, dominant and constant species. Ecological conditions of the groups were compared using indicator values. Nine groups were distinguished, four of them belonging strictly to the order Arrhenatheretalia. Each alliance of Arrhenatheretalia presented in the study area (Cynosurion, Arrhenatherion) was represented by two groups. Groups from these two alliances are separated along a light gradient, while groups of the same alliance differ in nutrient values. Within Cynosurion, the nutrient-poor group cannot be identified unambiguously as any syntaxa previously known from Hungary. The nutrient-rich Cynosurion meadows are similar to LolioâCynosuretum, however, they show a stronger relationship with wet meadows. Within Arrhenatherion, PastinacoâArrhenatheretum is recognised as a hay meadow of nutrient-rich soils. The other meadow type is similar to FilipenduloâArrhenatheretum, thus raising syntaxonomical problems. There are transitional groups towards semi-dry and wet meadows, one dynamic phase and one outlier group among the other five clusters
Between the VinÄa and Linearbandkeramik worlds: the diversity of practices and identities in the 54thâ53rd centuries cal BC in south-west Hungary and beyond
Szederkény-Kukorica-dƱlĆ is a large settlement in south-east Transdanubia, Hungary, excavated in advance of road construction, which is notable for its combination of pottery styles, variously including VinÄa A, RaĆŸište and LBK, and longhouses of a kind otherwise familiar from the LBK world. Formal modelling of its date establishes that the site probably began in the later 54th century cal BC, lasting until the first decades of the 52nd century cal BC. Occupation, featuring longhouses, pits and graves, probably began at the same time on the east and west parts of the settlement, the central part starting a decade or two later; the western part was probably abandoned last. VinÄa pottery is predominantly associated with the east and central parts of the site, and RaĆŸište pottery with the west. Formal modelling of the early history and diaspora of longhouses in the LBK world suggests their emergence in the Formative LBK of Transdanubia c. 5500 cal BC and then rapid diaspora in the middle of the 54th century cal BC, associated with the ‘earliest’ (älteste) LBK. The adoption of longhouses at Szederkény thus appears to come a few generations after the start of the diaspora. Rather than explaining the mixture of things, practices and perhaps people at Szederkény by reference to problematic notions such as hybridity, we propose instead a more fluid and varied vocabulary including combination and amalgamation, relationships and performance in the flow of social life, and networks; this makes greater allowance for diversity and interleaving in a context of rapid change
TRY plant trait database â enhanced coverage and open access
Plant traitsâthe morphological, anatomical, physiological, biochemical and phenological characteristics of plantsâdetermine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of traitâbased plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traitsâalmost complete coverage for âplant growth formâ. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and traitâenvironmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives
TRY plant trait database â enhanced coverage and open access
Plant traits - the morphological, anatomical, physiological, biochemical and phenological characteristics of plants - determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of traitâbased plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits - almost complete coverage for âplant growth formâ. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and traitâenvironmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives
The flora and vegetation of rocky outcrops in three municipalities in the northern region of CearĂĄ, Brazil: phytosociological characterization
Veja material suplementar em <https://doi.org/10.6084/m9.figshare.5915233.v2O presente estudo teve como objetivo identificar a flora e a vegetação dos afloramentos rochosos isolados e
de baixa altitude (lajedos), na vegetação de Caatinga Arbustiva Aberta, que se encontram nos municĂpios de
Sobral, GroaĂras e Santa QuitĂ©ria, no estado do CearĂĄ, Brasil e propor uma classificação fitossociolĂłgica para
estas comunidades xerófilas. Foram definidas cinco åreas de coleta de dados com elevada proporção de rochas
expostas (> 80%) onde as excursĂ”es de campo decorreram em março de 2014 e 2015 (3Âș56âS e 40Âș23âW, 4Âș01âS
e 40Âș05âW, 4Âș07âS e 40Âș08âW, 4Âș09âS e 40Âș09âW e 4Âș03âS e 40Âș00âW). No estudo da vegetação aplicou-se os
métodos TWINSPAN (two-way indicator species analysis) e o clåssico sigmatista de Braun-Blanquet. As åreas
mĂnimas dos inventĂĄrios fitossociolĂłgicos variaram de 8 a 16 m2. Foram coletadas as espĂ©cies vegetais que
crescem em fissuras, fendas e ilhas de vegetação que se encontram em afloramentos rochosos. Foram registradas
88 espĂ©cies, distribuĂdas em 59 gĂȘneros e 30 famĂlias botĂąnicas. Fabaceae foi a famĂlia que se destacou em riqueza
especĂfica (20 spp.), seguida por Poaceae (dez spp.), Euphorbiaceae (sete spp.) e Convolvulaceae (seis spp.).
Quanto ao endemismo foram registradas, em vegetação rupestre, 19 espĂ©cies endĂȘmicas para o Brasil. Na anĂĄlise
fitossociológica da vegetação propÎs-se estudar a comunidade de Pilosocereus gounellei (FA.C.Weber) Byles &
Rowley e Encholirium spectabile Mart. ex Schult. & Schult.f. e a de Crateva tapia L. e Combretum leprosum Martinfo:eu-repo/semantics/publishedVersio
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