Search results for "GRAS"

Grasslands and Shrublands of the Mediterranean Region

2020

The Mediterranean Region extends to the 1.6% of the world’s land surface and more than the half of the Mediterranean-type ecosystems of the world. The remarkable species richness in the Mediterranean Region mainly originates from an exceptional habitat diversity and the presence of several natural barriers facilitating the segregation and differentiation of local taxa and biocoenoses. In this article, we deal with the habitats characterized by grasslands and shrublands that clearly show the adaptations to what could be called “the Mediterranean syndrome”, i.e., the intrazonal Mediterranean grasslands and shrublands (MG&S). The main driving forces of the adaptive radiation and high biodi…

Climate change and Mediterranean seagrass meadows: a synopsis for environmental managers

2014

12 páginas, 3 figuras

Random amplified polymorphic DNA assessment of diversity in western Mediterranean populations of the seagrass Posidonia oceanica.

2003

Posidonia oceanica is an endemic Mediterranean seagrass species that has often been assumed to contain low levels of genetic diversity. Random amplified polymorfic DNA (RAPD) markers were used to assess genetic diversity among five populations from three geographical regions (north, central, and south) of the western Mediterranean Sea. Stranded germinating seeds from one of the central populations were also included in the analysis. Forty-one putative genets were identified among 76 ramets based on 28 RAPD markers. Genotypic diversity strongly depended on the spatial structure, age, and maturity of the meadows. The lowest clonal diversity was found in the less structured and youngest prairi…

Abrupt vegetation changes in the Segura Mountains of southern Spain throughout the Holocene

2001

Summary 1 The fossil pollen record of Canada de la Cruz in the Segura mountains of southern Spain yields insights into high-elevation vegetational dynamics over the last c. 8320 years. Phases of xerophytic grassland alternate with high-mountain open pine forests and expansion of deciduous forests and Mediterranean scrub at lower altitudes. 2 Longer-term stable vegetation patterns are interrupted by multidecadal to century-scale shifts at about 7770, 3370, 2630, 1525 and 790 years BP. 3 Some of the vegetation types have no modern analogues and represent high-altitude remnants of widespread last-glacial xerophytic communities. Other species patterns, characteristic of current scrub associatio…

Effects of different amendments (organic matter and hydrogel) on the actual evapotranspiration and crop coefficient of turf grass under field conditi…

2020

The irrigation schedule in arid areas has to be efficient in order to reduce losses due to evaporation and deep infiltration. Irrigation optimization poses the need to establish with precision the value of actual evapotranspiration (ETa), and the crop coefficient (Kc). The water soil availability can be increased using hydrogel and organic matter amendments, and their effects could vary ETa and Kc. The aim of this study was to determine the ETa, and Kc of an experimental site with lysimeters on the Spanish Mediterranean coast cropped with a turf grass variety, Agrostis stolonifera ‐L‐93, under field conditions, and amended with hydrogel and organic matter. Reference evapotranspiration (ET0)…

Soil aggregate stability under different Mediterranean vegetation types

1998

The influence of vegetation type on soil erodibility was studied by means of aggregate stability measurements using the Modified Emerson Water Dispersion Test (MEWDT), water-drop impacts (CND and TDI) and Ultrasonic Disruption (UD) methods on soils from north-facing slopes of the mountain range of La Serra Grossa in the eastern Iberian Peninsula. Soils with similar characteristics but covered by the main plant species at the study area were selected. Quercus ilex woodland showed the most resistant soil aggregates followed by Q. coccifera and Pistacea lentiscus scrubland, Brachypodium retusum grassland and Pinus halepensis woodland. Aggregates developed beneath dwarf shrubs like Rosmarinus o…

New insight on Mediterranean and sub-Mediterranean syntaxa included in the Vegetation Prodrome of Italy

2015

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…

Lack of mitochondrial toxicity of darunavir, raltegravir and rilpivirine in neurons and hepatocytes: a comparison with efavirenz.

2014

Objectives Growing evidence associates the non-nucleoside reverse transcriptase inhibitor efavirenz with several adverse events. Newer antiretrovirals, such as the integrase inhibitor raltegravir, the non-nucleoside reverse transcriptase inhibitor rilpivirine and the protease inhibitor darunavir, claim to have a better toxicological profile than efavirenz while producing similar levels of efficacy and virological suppression. The objective of this study was to determine the in vitro toxicological profile of these three new antiretrovirals by evaluating their effects on the mitochondrial and cellular parameters altered by efavirenz in hepatocytes and neurons. Methods Hep3B cells and primary …

Advanced Strategies for Food-Grade Protein Production: A New E. coli/Lactic Acid Bacteria Shuttle Vector for Improved Cloning and Food-Grade Expressi…

2019

Food-grade production of recombinant proteins in Gram-positive bacteria, especially in LAB (i.e., Lactococcus, Lactobacillus, and Streptococcus), is of great interest in the areas of recombinant enzyme production, industrial food fermentation, gene and metabolic engineering, as well as antigen delivery for oral vaccination. Food-grade expression relies on hosts generally considered as safe organisms and on clone selection not dependent on antibiotic markers, which limit the overall DNA manipulation workflow, as it can be carried out only in the expression host and not in E. coli. Moreover, many commercial expression vectors lack useful elements for protein purification. We constructed a &ld…