Search results for "Shrub"
showing 10 items of 101 documents
Holocene history of Aleppo pine (Pinus halepensis Mill.) woodlands in the Ebro Basin (NE Spain). Climate-biased or human-induced?
2020
Abstract This paper reviews the past distribution of Aleppo pine woodlands in the Ebro Basin, Northeastern Iberia, from the Mesolithic to Modern times based on wood charcoal data. The aim is to detail the chronological timing and the drivers explaining the long-term presence of Aleppo pine woodlands and associated thermophilous flora. The available charcoal data support the early spread of Pinus halepensis during the Mesolithic (ca. 9000 cal BP) accompanied by Mediterranean trees and shrubs like Quercus sp. evergreen, Juniperus sp., Arbutus unedo, Pistacia lentiscus, Rhamnus/Phillyrea, Cistaceae, and Rosmarinus officinalis, as a local response to global climate change in the Early Holocene.…
Drought and its legacy modulate the post-fire recovery of soil functionality and microbial community structure in a Mediterranean shrubland.
2019
The effects of drought on soil dynamics after fire are poorly known, particularly its long-term (i.e., years) legacy effects once rainfall returns to normal. Understanding this is particularly important for nutrient-poor soils in semi-arid regions affected by fire, in which rainfall is projected to decrease with climate change. Here, we studied the effects of post-fire drought and its legacy on soil microbial community structure and functionality in a Cistus-Erica shrubland (Spain). Rainfall total and patterns were experimentally modified to produce an unburned control (natural rainfall) and four burned treatments: control (natural rainfall), historical control (long-term average rainfall),…
Plastid DNA Homogeneity in Celtis australis L. (Cannabaceae) and Nerium oleander L. (Apocynaceae) throughout the Mediterranean Basin
2015
International audience; Premise of research. Riparian plants are highly dependent on water sources; consequently, general climatic conditions are less important to these taxa relative to woodland and shrubland species. This leads to interesting research questions regarding riparian plant taxa. Research on phylogeography of Mediterranean riparian tree and shrub species is scarce. In this article, we investigated the plastidial genetic diversity in Celtis australis L. (hackberry) and Nerium oleander L. (oleander) throughout the Mediterranean Basin. Both species are distributed in gullies, rivers, and stream banks under warm temperate climates. Methodology. Eighteen cpSSR loci and three noncod…
Distribution, ecological role and symbioses of selected shrubby species in the Mediterranean Basin: a review
2020
Among the Mediterranean ecosystems, shrublands are a characteristic type of vegetation, widespread in different habitats. Owing to different factors such as the physiological, morphological, reproductive, phenological and regenerative properties, as well as the inter-intraspecific interactions, each shrubby species represents an important element within the plant community and plays a specific ecological role. In this review, attention was focused on the ecological functions and type of plant-microsymbiont interactions in respect of selected shrubby species within the Mediterranean Basin: Amelanchier ovalis, Astragalus nebrodensis, Crataegus laciniata, Lycium intricatum, Prunus spinosa and …
Dwarf shrub vegetation of rock ledges and clefts in the Pamir Alai Mountains (Middle Asia: Tajikistan)
2016
AbstractThe paper presents the results of phytosociological researches on rocky slope vegetation in Tajikistan with the aim to establish a comprehensive syntaxonomical classification system. Field studies were conducted in 2010-2014 in Pamir Alai ranges and Pamirian plateau. Nearly 500 relevés documenting rock and scree vegetation were made according to the Braun-Blanquet method. Numerical analyses of selected 58 relevés representing dwarf shrub vegetation on rock ledges made it possible to distinguish: Ephedro glaucae- Spiraeion baldschuanicae and Ephedrion regeliano-fedtschenkoi alliances, as well as Spiraeetum baldschuanicae, Rhamnetum coriaceae, Pentaphylloidetum parvifoliae and Pentaph…
Mechanisms of shrub encroachment into Northern Chihuahuan Desert grasslands and impacts of climate change investigated using a cellular automata model
2016
Arid and semiarid grasslands of southwestern North America have changed dramatically over the last 150 years as a result of woody plant encroachment. Overgrazing, reduced fire frequency, and climate change are known drivers of woody plant encroachment into grasslands. In this study, relatively sim- ple algorithms for encroachment factors (i.e., grazing, grassland fires, and seed dispersal by grazers) are proposed and implemented in the ecohydrological Cellular-Automata Tree Grass Shrub Simulator (CAT- GraSS). CATGraSS is used in a 7.3 km 2 rectangular domain located in central New Mexico along a zone of grassland to shrubland transition, where shrub encroachment is currently active. CATGraS…
Strong regionality and dominance of anaerobic bacterial taxa characterize diazotrophic bacterial communities of the arcto-alpine plant species Oxyria…
2017
Arctic and alpine biomes are most often strongly nitrogen-limited, and hence biological nitrogen fixation is a strong driver of these ecosystems. Both biomes are characterized by low temperatures and short growing seasons, but they differ in seasonality of solar radiation and in soil water balance due to underlying permafrost in the Arctic. Arcto-alpine plant species are well-adapted to the low temperatures that prevail in their habitats, and plant growth is mainly limited by the availability of nutrients, in particular nitrogen, due to slow mineralization. Nitrogen fixing bacteria are likely important for plant growth in these habitats, but very little is known of these bacteria or forces …
Plant-animal interactions in fire-prone ecosystems
2018
SÍNTESIS Estudiar cómo responden las interacciones ecológicas a las perturbaciones es clave para abordar la creciente pérdida de biodiversidad en diferentes ecosistemas. En la Tierra existen especies que han evolucionado ante la presencia recurrente de perturbaciones naturales, como ocurre en ecosistemas con incendios frecuentes. En ellos el fuego se originó poco después de la aparición de las primeras plantas terrestres y también algunos de los patrones de incendios característicos que todavía permanecen. Sin embargo, las actividades humanas están alterando los patrones naturales de incendios, lo que puede suponer una amenaza incluso para las especies que presentan una rápida recuperación …
Optimal timing of power line rights-of-ways management for the conservation of butterflies
2012
Habitat loss, fragmentation, and degradation are the main threats to biodiversity. Human activities also create new habitat types that might fulfil ecological requirements for a variety of species. This study investigates whether the vegetation clearing (=shrub and tree cutting) on drained mire patches on power line rights-of-ways (ROWs) keep plant communities in an early successional stage and thus provide habitats for mire specialist and non-mire butterflies. It was further studied what would be the optimal clearing interval in terms of butterfly species richness and abundance. The results show that tree height, especially the height of birch, increases linearly over the 7-year period fol…
Proposals for improvement of Annex I of Directive 92/43/ EEC: Central Italy
2021
The main purpose of the 92/43/EEC Habitats Directive is to contribute to the conservation of biodiversity, understood as habitat types and species of the flora and fauna of the European Union. To achieve this goal, natural and semi-natural biodiversity as a whole must be recognized and included in its annexes. As for the conservation of biotopes, named habitat types, Italy is unfortunately lacking as it the Annex I does not include important ecosystems that are typical of its territory, rare for biogeographical reasons or threatened. Therefore, the opportunity to identify a first list of significant habitats for central Italy is discussed here. For each of the new proposed types (new habita…