Search results for "Systematics"

Invasion ecology of the alien tussock grassNardus stricta(Poaceae) at Lake Pukaki, Canterbury, New Zealand

2005

Abstract The European matgrass Nardus stricta has naturalised in New Zealand, often on damp soils within wetlands and grasslands. In this paper, we present for the first time field data on the ecology of this alien invader in New Zealand, from eight kettle‐hole wetlands on lateral moraine along the western side of Lake Pukaki, South Canterbury. The invaded wetland sites were all acidic but varied in other soil characteristics. Nardus stricta was the most dominant species within these wetland communities with 40% of all plots showing more than 50% coverage, and 21% having more than 90% cover. Species richness (including vascular plants and mosses) at some sites was relatively high (c. 40 spe…

Response of wood-inhabiting fungal community to fragmentation in a beech forest landscape

2014

Fragmentation of natural habitats has become one of the main causes of the loss of biodiversity. To assess the effects of forest fragmentation on wood-inhabiting fungal community in a beech-dominated landscape, 15 differently shaped beech forest fragments were examined in northern Spain. This work covers all the wood-inhabiting macromycetes, including Basidiomycota and Ascomycota. A modelling approach was used to examine the predictability of the fungal community in a fragmented beech forest landscape. In the beech forest patches, a large proportion of edge, low tree densities and low levels of variety of woody debris caused a decrease of wood-inhabiting fungal richness. The fungal communit…

Zooplankton communities in doline lakes and pools, in relation to some bathymetric parameters and physical and chemical variables

1999

The zooplankton communities from several lakes and pools in three zones of a karstic area in central Spain were studied in spring and early autumn, in relation to morphometric, physical and chemical characteristics of the lakes. Zooplankton diversity was higher in autumn than in spring and it was positively correlated with lake size (area and depth) in spring, but not in early autumn. This effect is partially explained by the sharp zooplankton stratification in deep lakes, in early autumn. Some morphometric characteristics of lake basins were also correlated with the structure of zooplank- ton communities. Principal component analyses (PCA) and Two-Way Indicator Species Analysis (TWINSPAN) …

Spatial and temporal variability of diatom and macroinvertebrate communities: How representative are ecological classifications within a river system?

2012

Evaluation of river condition is complicated by dynamic relationships between river assemblages and their environment. We assessed variation of ecological status classifications of stream diatom and macroinvertebrate communities within a boreal river system. We specifically examined whether results of ecological classifications are concordant across taxonomic groups and among main channel and headwater side tributaries of this river system. We further assessed whether ecological classifications are stable from year to year and whether classifications show predictable relationships to major stressor gradients. The estimated ecological condition varied considerably among and between reaches o…

Yet another alien: a second species of Lepisiota spreading across the Canary Islands, Spain (Hymenoptera: Formicidae)

2018

The Canary Islands are a biologically important archipelago hosting many unique species, whose myrmecofauna is peculiarly rich in both endemic and introduced species. Lepisiota frauenfeldi cfr. kantarensis Forel, 1911 is reported for the first time from Fuerteventura and Tenerife. It is the second species of Lepisiota introduced in the archipelago in the last few years, and one of the few documented cases in which Lepisiota frauenfeldi (Mayr, 1855) s.l. acts as a successful tramp species. Comments are also given on taxonomic problems involving the L. frauenfeldi-group and related taxa. Finally, new additional information and comments are presented on the distribution of other alien ants spe…

Changes in alpine snowbed-wetland vegetation over three decades in northern Norway

2013

We have quantified floristic changes in alpine snowbeds and wetland vegetation during three decades and analyzed to what extent these changes are related to initial variations in snow cover duration and distance to groundwater level. Vascular plant species richness and total plant cover were estimated along three transects in northern Norway. Three different vegetation zones were identified along the original transects: relatively dry snowbeds, wet snowbeds and wetlands. The resampling shows major changes in species richness and plant cover. In general, there was a net immigration of species and 13 new species were found. Five rare species with initial low cover were lost. In the dry and we…

The Body Size of Headstarted and Wild Juvenile European Pond Turtles (<i>Emys orbicularis</i>)

2017

Headstarting is a popular conservation technique in which animals are raised under artificial conditions, and then released into natural habitat. The objective of this procedure is to grow animals to a size at which they are less vulnerable to predators. However, there is still little empirical evidence for the long-term effectiveness of the technique. Therefore, we compared body size of juvenile «wild» (= not taken to artificial rearing) and headstarted European pond turtles ( Emys orbicularis ), from two populations (in central and western Poland). Immediately after hatching there were no differences in size of the turtles, but after seven-ten years headstarted turtles were smaller. This …

Sensory performance of blind Mexican cave fish after destruction of the canal neuromasts.

1990

The identity and geographical distribution of Jacobaea vulgaris subsp. gotlandica , supposedly endemic to Gotland and Öland (Sweden)-the importance o…

2009

The identity of Jacobaea vulgaris Gaertn. subsp. gotlandica (Neum.) B. Nord., hitherto considered an endemic to the Swedish islands Oland and Gotland, was investigated using nrITS and trnT-trnL intergenic spacer sequences and a broad sample of species and accessions particularly of J. vulgaris. We found that J. vulgaris subsp. gotlandica is a distinct evolutionary lineage more widespread in Europe than previously thought and may be a southeastern European steppe floristic element with outliers on the large Baltic islands. Our entirely unexpected findings underline the need of multiple intraspecific sampling in species-level phylogenetic studies.

A new subspecies of Rosmarinus officinalis (Lamiaceae) from the eastern sector of the Iberian Peninsula

2014

Rosmarinus officinalis subsp. valentinus (Lamiaceae) is described as a new subspecies in the flora of the Iberian Peninsula. The diagnostic characters for the subsp. valentinus include several morphological differences, mainly based on a distinctly prostrate habit, a reduced leaf size, smaller calyx and corolla, and white flower. A comparative table with diagnostic morphological features to distinguish among the three subspecies of the R. officinalis is provided. Habitat, ecology, greenhouse cultivation and phenolic profile are also considered.