Search results for " grassland"

Origin and evolution of the Mediterranean dry grasslands.

2007

In the Mediterranean region, three main structural types of dry grasslands can be recognized: those dominated by perennial caespitose grasses (wintergreen perennial dry grasslands, Lygeo-Stipetea), those dominated by thermoxerophilous therophytes (ephemeral dry grasslands, Tuberarietea guttatae), those dominated by chamaephytes, thistles and relatively small hemicryptophytes (summergreen perennial dry grasslands, Festuco-Brometea). All three kinds are commonly represented all over the Mediterranean territories, especially in the dry most areas. Relevant physiognomic, adaptive and floristic differences are featuring the three mentioned typologies. Lygeo-Stipetea and Festuco-Brometea may grad…

Low effective population sizes and limited connectivity inxerothermic beetles: implications for the conservation ofan endangered habita

2014

Fragmentation and isolation may have detrimental effects on the viability of populations. Xerothermic grasslands, which are extra-zonal analogues of steppes, are among Europe's most endangered natural environments. Information about connectivity between the remaining habitat patches is critical for effective conservation planning. However, very little is known about the actual levels of isolation of individual xerothermic patches at the inter-regional and local scale. In this study, 16 microsatellite loci were used to investigate genetic diversity, structuring, effective sizes (Ne), and connectivity among populations of the weevil Centricnemus leucogrammus at various geographic scales. Anal…

The Lygeo-Stipetea class in Sicily

2009

Short-term low-severity spring grassland fire impacts on soil extractable elements and soil ratios in Lithuania

2017

Abstract Spring grassland fires are common in boreal areas as a consequence of slash and burn agriculture used to remove dry grass to increase soil nutrient properties and crop production. However, few works have investigated fire impacts on these grassland ecosystems, especially in the immediate period after the fire. The objective of this work was to study the short-term impacts of a spring grassland fire in Lithuania. Four days after the fire we established a 400 m2 sampling grid within the burned area and in an adjacent unburned area with the same topographical, hydrological and pedological characteristics. We collected topsoil samples immediately after the fire (0 months), 2, 5, 7 and …

Scale-dependent patterns and drivers of vascular plant, bryophyte and lichen diversity in dry grasslands of the Swiss inneralpine valleys

2022

AbstractThe inner-alpine dry valleys of the Swiss Alps are characterized by subcontinental climate, leading to many peculiarities in dry grassland species composition. Despite their well-known uniqueness, comprehensive studies on biodiversity patterns of the dry grasslands in these valleys were still missing. To close this gap, we sampled 161 10-m2 vegetation plots in the Rhône, Rhine and Inn valleys, recording vascular plants, terricolous bryophyte and lichen species, as well as environmental data. Additionally, we tested the scale-dependence of environmental drivers using 34 nested-plot series with seven grain sizes (0.0001–100 m2). We analysed the effects of environmental drivers related…

Milk fatty acids of cows grazing a mountain diversified grassland is highly affected by the maturity stage of the grass.

2009

On the origin and evolution of the Mediterranean dry grasslands.

2006

A synthesis on the functional types of Mediterranean dry grasslands is outlined. Three different types are outlined: wintergreen perennial dry grasslands, wintergreen ephemeral dry grasslands, summergreen perennial dry grasslands. The first type is the most primitive, including several relict species, often characterized by very disjoint, sometimes anfi-saharian distribution ranges. The second type is resulting from an evolutionary trend towards short-lived life strategy, triggered by climatic and topographic perturbations that affected the Mediterranean region in the Plio- and Pleistocene. The third type, only marginally occurring in the Mediterranean region, is deriving from Holarctic and…

An “Uncertainty Principle” for the Mediterranean annual dry grasslands

2009

Preliminary results of diachronic researches on the spatial arrangement and species richness in Mediterranean annual dry grasslands (Tuberarietea guttatae) demonstrated that the patchiness resulted minimized and the temporal stability maximized at elevations offering the best compromise between the summer drought stress and the winter cold stress. Moreover, the temporal stability of the Mediterranean annul dry grasslands could not necessarily be related with their demographic inertia, meaning that the turnover and rearrangement of species within the community do not necessarily implicate significant changes in the average species composition over time. On the other hand, the survival chance…

Impressions from the 4th EDGG Research Expedition to Sicily: community composition and diversity of Mediterranean grasslands.

2012

Effects of temperatures on the spatial arrangement in Mediterranean annual dry grasslands

2009

Some preliminary results of diachronic researches on the spatial arrangement and species richness in Mediterranean annual dry grasslands belonging to the class Tuberarietea guttatae are presented. Our results are based on 12 permanent plots, set in three places at different heights in Southern and Central Sardinia. Sites were chosen to have annual species richness and plant density not significantly different. The relationship between patchiness and temporal stability was investigated at the scale of the square plots. We used the mean abundance divided by the SD in abundance (S = xm/r), as the measure of temporal stability of populations (Tilman 1999) and the Shannon-Wiener index to evaluat…