Search results for "GRASSLAND"

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…

Soil Fungal Community in Grazed Inner Mongolian Grassland Adjacent to Coal-Mining Activity.

2021

Coal mining results in reduced soil quality and makes environments less stable. Soil fungi are suitable indicators of soil quality for monitoring purposes. Here, the objective was therefore to investigate the effects of grazing and mining on the composition of the soil fungal community at the periphery of an opencast coal-mine dump in the Shengli mining area, Xilingol League, Inner Mongolia. A total of 2110 fungal operational taxonomic units (OTUs) were identified and subdivided into 81 orders and nine categories, based on trophic modes. The sensitivity of soil factors to coal-mining and grazing was differently. The sensitive factor to mining was soil pH, and that to grazing were soil nitra…

Bacterial and Archaeal Communities Change With Intensity of Vegetation Coverage in Arenized Soils From the Pampa Biome

2019

Arenization occurs in regions that present sandy soils with normal rainfall levels. Predatory use of environmental sources, the dissolution of arenitic rocks and reworking of non-consolidated surface sands intensify this degradation scenario. Thus, this work aimed to evaluate the impact of the arenization process in the Brazilian Pampa Biome and how this phenomenon affects the soil microbial and plant communities. For this purpose, three arenized areas in Southern Brazil (Pampa Biome) were selected and, in each one, three sampling points were studied: arenized (ARA), arenized to grassland transition (AGT), and grassland (GRA) areas. In the three sampling points, soils presented low levels o…

Pseudosteppes and related grassland vegetation in the Pamir-Alai and western Tian Shan Mts – the borderland of the Irano-Turanian and Euro-Siberian r…

2020

The aim of our study was to complete the syntaxonomical scheme for grassland vegetation of the lowland, montane and alpine zones in the Pamir-Alai and western Tian Shan Mts in Tajikistan and Kyrgyzstan with some remarks on its environmental predictors. A total of 198 relevés were sampled in 2013–2018 using the seven-degree cover-abundance scale of the Braun-Blanquet approach. They were classified with k-means algorithm with tranforming cover values to three level scale of the following intervals 0%, 5% and 25% and total inertia as a measure of cluster heterogeneity. Diagnostic species were identified using the phi coefficient as a fidelity measure. Non-metric Multidimensional Scaling (NMDS)…

Nitrous oxide emission budgets and land-use-driven hotspots for organic soils in Europe

2014

Organic soils are a main source of direct emissions of nitrous oxide (N2O), an important greenhouse gas (GHG). Observed N2O emissions from organic soils are highly variable in space and time, which causes high uncertainties in national emission inventories. Those uncertainties could be reduced when relating the upscaling process to a priori-identified key drivers by using available N2O observations from plot scale in empirical approaches. We used the empirical fuzzy modelling approach MODE to identify main drivers for N2O and utilize them to predict the spatial emission pattern of European organic soils. We conducted a meta-study with a total amount of 659 annual N2O measurements, which was…

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…

Polychlorinated biphenyls (PCBs) in soils of the Moscow region: Concentrations and small-scale distribution along an urban–rural transect

2006

In soils of the Moscow region, we examined PCB concentrations in bulk samples and aggregate fractions. Topsoils under grassland and forest at five locations along a southeast-bound transect from Moscow and at a northeastern background location (grassland only) were analysed. We collected aggregates1 cm and fractionated them into interior and exterior portions and also analysed the remaining soil without the aggregates1 cm. The concentrations of the sum of 17 PCBs (sigma17PCBs) in 35 bulk soil samples ranged from 3.1 to 42 microg kg(-1). This was 48-61% of the sigma33PCBs determined in 23 selected samples. The congeners 138(+158), 101 and 52 were most abundant. All PCB concentrations and the…

The Lygeo-Stipetea class in Sicily

2009

Long-term soil feedback on plant N allocation in defoliated grassland miniecosystems

2005

Abstract Defoliation of plants is known to have effects on soil organisms and nutrient availability in grassland communities, but few studies have examined whether changes in soil attributes can further feed back to plant growth and plant nutrient content. To examine defoliation-induced soil feedbacks, we established replicated miniecosystems with a grass Phleum pratense , defoliated half of the systems, collected soil from both defoliated and non-defoliated systems and planted new seedlings into each soil. The two soils did not differ in promoting shoot and root growth. However, seedlings that grew in the soil collected from defoliated systems had higher shoot N content, allocated relative…