Search results for "SUCCESSION"
showing 10 items of 401 documents
Fire disturbance disrupts co-occurrence patterns of terrestrial vertebrates in Mediterranean woodlands
2006
Aim This paper uses null model analysis to explore the pattern of species co-occurrence of terrestrial vertebrate fauna in fire-prone, mixed evergreen oak woodlands. Location The Erico–Quercion ilicis of the Mediterranean belt (50–800 m a.s.l.) in the Madonie mountain range, a regional park in northern Sicily (37°50′ N, 14°05′ E), Italy. Methods The stratified sampling of vertebrates in a secondary succession of recent burned areas (BA, 1–2 years old), intermediate burned areas (INT, 4–10 years old) and ancient burned areas (CNB, > 50 years old), plus forest fragments left within burned areas (FF, 1–2 years old) permitted the comparison of patterns of species co-occurrence using a set of…
Integrating Extensive Livestock and Soil Conservation Policies in Mediterranean Mountain Areas for Recovery of Abandoned Lands in the Central Spanish…
2016
Land abandonment is a global issue with important implications in Mediterranean mountain areas. Abandoned Mediterranean croplands start a process of secondary succession that is initially colonized by grasslands, shrubs and forest. In Mediterranean mountain areas, the process is very slow, so the shrubs remain for decades, preventing livestock from accessing pastureland. Therefore, farmers have to burn or clear the shrubs in order to provide pasture, a practice that has recently been encouraged by several regional governments in Spain. Data from experimental plots of the Aisa Valley Experimental Station in the Spanish Pyrenees allow to evaluate the effects of burning and clearing shrubs on …
An empirical test of neighbourhood effect and safe-site effect in abandoned Mediterranean vineyards
2011
The importance of both neighbourhood effect and safe-site effect for the colonization of Mediterranean old fields by woody plants was investigated. Using a transect approach, we recorded colonization of 21 species of woody plants on abandoned, terraced vineyards on Pantelleria Island (Sicily) in dependence from neighbouring terraces in older succession stages (Maquis) and available safe sites for seedling establishment (former crop plant, terrace wall). With a paired design of four treatments, including presence/absence of adjacent older successional stages, and North-/South-facing slopes, a neighbourhood effect could be shown for both expositions if the transect started from an adjacent fi…
A chronosequence study of vegetation dynamics on vine and caper terraces of Pantelleria Island (Sicily)
2006
The vegetation of fallow fields of different age in the terraced agricultural landscape of Pantelleria Island (Sicily) was analysed via vegetation relevés. Five age classes in N-facing as well as in S-facing slopes of both vine and caper fallows were differentiated. The main questions were to determine the sequence of plant communities in time and to test some environmental factors for their influence on the course and the speed of succession. The results show that undisturbed abandoned terraces are subject to rapid renaturation: 50 to 80 years old fallows are now covered by dense maquis communities. Both N- and S-facing slopes seem to converge to a Quercus ilex woodland as the climax commu…
la noblesse dans la monarchie espagnole des Habsbourg aux Bourbons. Langages et pratiques de fidélités anciennes et nouvelles
2018
Lo scopo del saggio è di offrire una riflessione sulla nobiltà spagnola, siciliana e napoletana nel complesso quadro della crisi dinastica verificatasi nella monarchia spagnola alla morte di Carlo II. A partire dall'analisi delle dinamiche che hanno iniziato a modificare il ruolo delle Grandes alla corte di Madrid durante la reggenza di Mariana de Austria, l'attenzione si concentra principalmente sui decenni tra la fine del XVII e l'inizio del XVIII secolo. La ricerca evidenzia strategie personali e legali, nuove pratiche e linguaggi di negoziazione tra nobiltà e sovrano, al fine di comprendere le motivazioni che hanno costituito la base per l'adesione della nobiltà mediterranea al partito …
Avoiding patterns in irreducible permutations
2016
We explore the classical pattern avoidance question in the case of irreducible permutations, <i>i.e.</i>, those in which there is no index $i$ such that $\sigma (i+1) - \sigma (i)=1$. The problem is addressed completely in the case of avoiding one or two patterns of length three, and several well known sequences are encountered in the process, such as Catalan, Motzkin, Fibonacci, Tribonacci, Padovan and Binary numbers. Also, we present constructive bijections between the set of Motzkin paths of length $n-1$ and the sets of irreducible permutations of length $n$ (respectively fixed point free irreducible involutions of length $2n$) avoiding a pattern $\alpha$ for $\alpha \in \{13…
The use of vegetation as a natural strategy for landfill restoration
2018
The Root Mycobiota of Betula aetnensis Raf., an Endemic Tree Species Colonizing the Lavas of Mt. Etna (Italy)
2021
Betula aetnensis is an endemic tree of high conservation value, which thrives on the nutrient-poor volcanic soils of Mount Etna. Since plant–microbe interactions could play a crucial role in plant growth, resource uptake, and resistance to abiotic stresses, we aimed to characterize the root and rhizosphere microbial communities. Individuals from natural habitat (NAT) and forest nursery (NURS) were surveyed through microscopy observations and molecular tools: bacterial and fungal automated ribosomal intergenic spacer analysis (ARISA), fungal denaturing gradient gel electrophoresis (DGGE). B. aetnensis was found to be simultaneously colonized by arbuscular (AM), ectomycorrhizal (ECM), ericoid…
Seasonal succession of phytoplankton in an ice-free pond warmed by a thermal power plant
1982
In a pond receiving warmed cooling waters from a thermal power plant, the physical and chemical properties of the water, phytoplankton, periphyton and zooplankton were monitored on a weekly sampling schedule. In winter the phytoplankton growth was limited by poor light conditions. In mid-February a rapid phytoplankton growth started, simultaneously with increasing light energy, high nutrient concentrations and small herbivorous zooplankton populations. The increase of phytoplankton biomass was stopped by lack of free nutrients and silica at the end of March. From May until August the phytoplankton standing crop was mainly regulated by herbivorous zooplankton. The autumnal maximum of phytopl…
Yearly succession of the phytoplankton in an ice-free pond in central Finland
1981
Seasonal succession of the phytoplankton was studied with shortinterval sampling in an eutrophic pond warmed during winter months by a small thermal power plant in central Finland since Octover 1978. Simultaneously with phytoplankton, also physical and chemical properties of water and zooplankton were studied.