Search results for "GRASSLAND"
showing 10 items of 161 documents
Does grassland cover limit the replenishment of weed seed banks during seed rain?
2012
International audience
Parameterizing the "grassland" module in the multispecific model FlorSys
2013
EAEcolDurCT1; The multispecies model FlorSys can predict the effects of cropping systems on the dynamics of weed communities in annual crops ; however, it is not configured to predict the fate of weeds in permanent cover such as grasslands. We realized the simulation of a weed seed rain in controlled conditions to estimate the percentage of weed seeds intercepted by a grass cover. Parameters of this linear model will be used to develop a new sub model in FlorSys to be able to simulate weed dynamics in temporary grasslands. We used twelve weed species selected on the basis of specific morphological characteristics and observations made in the experimental set up of SOERE ACBB (Observatory En…
Agroecological potential and prospects of alternative use of natural feed resources for bioenergetics
2018
Produkcja biomasy dla biogazu, paliw stałych i ciekłych jest ważna w szerokim zakresie zastosowań niekonwencjonalnych źródeł energii. Jednakże produkcja i wykorzystanie biomasy do celów energetycznych również wymaga kosztów finansowych i prowadzi do zmian w strukturze obszarów upraw w produkcji rolnej. Czynniki te powodują wzrost cen produktów rolnych. Zmiana klimatu i wysokie koszty zasobów mineralnych przyczyniają się do poszukiwania i rozwoju nowych sposobów pozyskiwania zasobów energetycznych. Badania nad produkcją biomasy z użytków zielonych w celach energetycznych są w Europie istotne i priorytetowe, a ich wyniki mają ogromną wartość praktyczną. Dlatego konieczne jest rozwiązanie prob…
Fine-grain beta diversity in Palaearctic open vegetation: variability within and between biomes and vegetation types
2021
Aims: To quantify how fine-grain (within-plot) beta diversity differs among biomes and vegetation types. Study area: Palaearctic biogeographic realm. Methods: We extracted 4,654 nested-plot series with at least four different grain sizes between 0.0001 m² and 1,024 m² from the GrassPlot database spanning broad geographic and ecological gradients. Next, we calculated the slope parameter (z-value) of the power-law species–area relationship (SAR) to use as a measure of multiplicative beta diversity. We did this separately for vascular plants, bryophytes and lichens and for the three groups combined (complete vegetation). We then tested whether z-values differed between biomes, ecological-physi…
Scale-dependent plant diversity in Palaearctic grasslands: a comparative overview
2016
Here we present an extensive overview of plant diversity values in Palaearctic grasslands for seven standard grain sizes from 0.0001 to 100 m². The data originate from 20 studies, including the Field Workshops of the Eurasian Dry Grassland Group (EDGG), ranging geographically from Spain in the west to Siberia in the east, from Sicily in the south to Estonia in the north and from the sea coast up to 3100 m a.s.l. The majority of data is from dry grasslands (Festuco-Brometea, Koelerio-Corynephoretea, Cleistogenetea squarrosae), but there are also some mesic, wet, saline, acidic, alpine and Mediterranean grasslands included. Among others, we compiled data from 1795 1-m², 1109 10-m² and 338 100…
Road verges provide alternative habitats for some, but not all, meadow plants
2021
Questions Agricultural intensification has led to the decline of biodiverse meadows and other semi-natural grasslands. Road verges offer potential alternative habitats for meadow species, but they may not be suitable for all meadow species due to different soil properties, frequent disturbances, pollution or suboptimal management. Are the communities of vascular plants and bryophytes similar or dissimilar to those in mown or grazed meadows? What kind of species are associated with road verges, mown meadows or grazed meadows? How do the habitat types differ in their soil conditions and disturbance intensity? Location The study was conducted on 36 sites in Central Finland. Methods We compared…
Short-term spatio-temporal spring grassland fire effects on soil colour, organic matter and water repellency in Lithuania
2013
Abstract. The aim of this work was to study the short-term effects (first 9 months after the fire) of a low-severity spring boreal grassland fire on soil colour, soils organic matter (SOM) and soil water repellency (SWR) in Lithuania. Three days after the fire we designed a plot of 400 m2 in a control (unburned) and unburned area with the same geomorphological characteristics. Soil water repellency analysis were assessed through the 2 mm mesh (composite sample) and in the subsamples of all of the 250 samples divided into different soil aggregate fractions of 2–1, 1–0.5, 0.5–0.25 and < 0.25 mm, using the Water Drop Penetration Time (WDPT) method. The results showed that fire darkened the …
Species–area relationships in continuous vegetation: Evidence from Palaearctic grasslands
2019
Aim Species-area relationships (SARs) are fundamental scaling laws in ecology although their shape is still disputed. At larger areas, power laws best represent SARs. Yet, it remains unclear whether SARs follow other shapes at finer spatial grains in continuous vegetation. We asked which function describes SARs best at small grains and explored how sampling methodology or the environment influence SAR shape. Location Palaearctic grasslands and other non-forested habitats. Taxa Vascular plants, bryophytes and lichens. Methods We used the GrassPlot database, containing standardized vegetation-plot data from vascular plants, bryophytes and lichens spanning a wide range of grassland types throu…
Numerical response of predators to large variations of grassland vole abundance, long-term community change and prey switches
2020
AbstractVoles can reach high densities with multi-annual population fluctuations of large amplitude, and they are at the base of large and rich communities of predators in temperate and arctic food webs. This status places them at the heart of management conflicts wherein crop protection and health concerns are often raised against conservation issues. Here, a 20-year survey describes the effects of large variations in grassland vole populations on the densities and the daily theoretical food intakes (TFI) of vole predators based on roadside counts. Our results show how the predator community responds to prey variations of large amplitude and how it reorganized with the increase in a domina…
Context-dependent foraging habitat selection in a farmland raptor along an agricultural intensification gradient
2021
Abstract Gradients of agricultural intensification in agroecosystems may determine uneven resource availability for predators relying on these man-made habitats. In turn, these variations in resource availability may affect predators’ habitat selection patterns, resulting in context-dependent habitat selection. We assessed the effects of gradients of landscape composition and configuration on habitat selection of a colonial farmland bird of prey, the lesser kestrel (Falco naumanni), relying on 76 GPS-tracked nestling-rearing individuals from 10 populations scattered along an agricultural intensification gradient. Analyses were conducted considering two ecological levels of aggregation (the …