| 1. |
- Frederiksen, Lise, et al.
(författare)
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A multivariate approach to plant community distribution in the coastal dune zonation of NW Denmark
- 2006
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Ingår i: Phytocoenologia. - 0340-269X. ; 36:3, s. 321-342
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Tidskriftsartikel (refereegranskat)abstract
- A near-natural coastal dune system in NW Jutland, Denmark was investigated. The area contains a gradient in natural soil mobility with the highest values in dynamic white dunes dominated by Ammophila arenaria, and low mobility in fixed decalcified dune heath with Empetrum nigrum and Calluna vulgaris. A total of 267 plots was investigated and presence of mosses and rooted vascular plants recorded. Cluster analysis identified five communities: white dune, grey dune, outer dune heath, inner dune heath and humid dune heath. These communities were ordered along two main axes in a Detrended Correspondence Analysis (DCA). The relationship between DCA axes and several environmental variables, including soil characteristics and Ellenberg indicator values, were investigated by correlation. Two major complex gradients underlying compositional variation were identified; one short coenocline with an underlying steep gradient in habitat maturity, soil stability and nutrient-limited productivity, and one longer gradient in water-limited productivity and peat accumulation only applying to the older successional stages. Distance from the coast was an important correlate of several of the measured variables. Microclimatic indices, i.e. heat index and wind index, had limited value as descriptors of community patterns as they were not correlated with the DCA axes or with other environmental variables. However, within communities the microclimatic indices correlated with several explanatory variables.
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| 2. |
- Shakeri, Zahed, et al.
(författare)
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Plant community composition and disturbance in Caspian Fagus orientalis forests : which are the main driving factors?
- 2012
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Ingår i: Phytocoenologia. - 0340-269X. ; 41:4, s. 247-263
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Tidskriftsartikel (refereegranskat)abstract
- The oriental beech forests along the southern Caspian Sea shores of Iran are characterized by high biodiversity and high ecological value. However, there is little information concerning factors governing community composition and the presence and abundance of invasive plants. In the present study we aimed to evaluate the main drivers of community composition, diversity, and establishment of invasive plants in disturbed and undisturbed Fagus orientalis communities. We sampled 104 vegetation releves in undisturbed and disturbed sites of the "Kheiroud Investigation Forest" in northern Iran and collected data on a large number of environmental variables concerning soil properties, light conditions, and topography. Data analysis consisted of a forward selection of significant explanatory variables followed by partial CCA analyses. Additionally, we carried out indicator species analysis of groups of releves affected by different disturbance types and analyzed effects of disturbance on species richness, diversity, and evenness using general linear models. CCA results showed that disturbance, soil properties, light conditions and elevation explained 22.6% of the total variation in floristic composition. Gap and gap + grazing were the most important disturbance types affecting community composition. Disturbance had significant but rather weak effects on species richness, evenness, and the Shannon index. The most obvious effect of disturbance was on species composition, as revealed by significant groups of indicator species for different disturbance types. Most of the indicator species in grazed sites were unpalatable, poisonous, and creeping species, which are avoided by cattle. Grazing led to decreased abundance of indicator species and species characteristic of old-growth Fagus forests. The most intensive disturbance type "harvesting + gap + grazing" was associated with invasion by native vascular plant species not typically found in beech forests (apophytes).
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| 3. |
- Dengler, Juergen, et al.
(författare)
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GrassPlot - a database of multi-scale plant diversity in Palaearctic grasslands
- 2018
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Ingår i: Phytocoenologia. - : Schweizerbart. - 0340-269X. ; 48:3, s. 331-347
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Tidskriftsartikel (refereegranskat)abstract
- GrassPlot is a collaborative vegetation-plot database organised by the Eurasian Dry Grassland Group (EDGG) and listed in the Global Index of Vegetation-Plot Databases (GIVD ID EU-00-003). GrassPlot collects plot records (releves) from grasslands and other open habitats of the Palaearctic biogeographic realm. It focuses on precisely delimited plots of eight standard grain sizes (0.0001; 0.001;... 1,000 m(2)) and on nested-plot series with at least four different grain sizes. The usage of GrassPlot is regulated through Bylaws that intend to balance the interests of data contributors and data users. The current version (v. 1.00) contains data for approximately 170,000 plots of different sizes and 2,800 nested-plot series. The key components are richness data and metadata. However, most included datasets also encompass compositional data. About 14,000 plots have near-complete records of terricolous bryophytes and lichens in addition to vascular plants. At present, GrassPlot contains data from 36 countries throughout the Palaearctic, spread across elevational gradients and major grassland types. GrassPlot with its multi-scale and multi-taxon focus complements the larger international vegetationplot databases, such as the European Vegetation Archive (EVA) and the global database " sPlot". Its main aim is to facilitate studies on the scale-and taxon-dependency of biodiversity patterns and drivers along macroecological gradients. GrassPlot is a dynamic database and will expand through new data collection coordinated by the elected Governing Board. We invite researchers with suitable data to join GrassPlot. Researchers with project ideas addressable with GrassPlot data are welcome to submit proposals to the Governing Board.
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