Search results for "sds"

Analysis of relationships between farming practices, weed flora and crop production

2015

International audience; Quantitative data on the potential losses of crop yield due to weeds is limited. Approaches toquantify weed damages considered only individual weed species, and have not included thecompounding of effects at the community level. Moreover they did not integrate the influence ofagricultural practices and environmental variables on the weed-crop relationship. Here weanalysed a big data sets to study relations between crop management, weed communities’indicators and crop yield and then develop path analysis models to disentangle the confoundingeffects of cropping system on weeds and crop production. Flora surveys (N= 651) were performedfrom 2006 to 2013 on 150 fields in …

The adaptation of cornflower in different compartments of the agricultural landscape

2015

International audience; Agrosystems are among habitats most affected by the decline of biodiversity. This decline isrelated to the intensification of agricultural practices carried out since the 50s (simplified rotations,fertilizer and pesticide use; ...). The study of the weed flora shows still less developed plantcommunities. Currently, there is evidence of the regression of the weed flora and especiallyspecies such as cornflower (Cyanus segetum. L). In western Europe, cornflower seems to bepresent in the field only. In our investigation, we tried to determine the factors that influence thepresence of cornflower in the different compartments of a field and its border.

Aptitude à la levée et à l'installation d'adventices dans des bandes enherbées. Quelles sont les réelles potentialités d'installation d'espèces adven…

2010

International audience

Diversifying crop rotations with perennial forage crops: potential benefits for weed management & farmland biodiversity

2010

Crop rotation may be used to prevent the continuous selection of weed species adapted to one crop type. However, today’s crop rotations are often very short and simple. We studied the impacts of introducing perennial forage crops into cereal-based crop rotations on weed vegetation. Large-scale weed surveys in 632 fields in western France suggested that the weed species composition varied most strongly between perennial alfalfa forage crops and six annual crops[1]. Comparisons of wheat fields before, during, and after perennial alfalfa suggested that weed communities vary in a cyclic way during such crop rotations. This may be beneficial for weed management (suppression of weed species probl…

Mating system adaptation in populations of Centaurea cyanus L.

2010

International audience; Since the 50s, the agriculture intensification in Western Europe resulted in landscape homogenizationand reduction of habitat connectivity, which in turn caused a widespread decline of farmland biological diversity.Centaurea cyanus is one of the declining “segetal species”. It is an annual and insect-pollinatedspecies with a self-incompatibility system. When the populations are small and fragmented, they mayextinct if the incompatibility system cannot evolve towards a compatibility system. A coexistence ofmixed mating system is also possible in a population.In our study, we examined the ability of C. cyanus to produce seeds by autogamy. For this purpose,three conditi…

Trois jours au cœur du COLUMA 2016

2012

Lutte contre les mauvaises herbes en France, dix lustres en lumière : Analyse de 50 ans d’usage des herbicides tirée d’une « mine »

2010

Widespread diminishing anthropogenic effects on calcium in freshwaters

2019

Calcium (Ca) is an essential element for almost all living organisms. Here, we examined global variation and controls of freshwater Ca concentrations, using 440 599 water samples from 43 184 inland water sites in 57 countries. We found that the global median Ca concentration was 4.0 mg L−1 with 20.7% of the water samples showing Ca concentrations ≤ 1.5 mg L−1 , a threshold considered critical for the survival of many Ca-demanding organisms. Spatially, freshwater Ca concentrations were strongly and proportionally linked to carbonate alkalinity, with the highest Ca and carbonate alkalinity in waters with a pH around 8.0 and decreasing in concentrations towards lower pH. However, on a temporal…

Biodiversité des sols viticoles: un héritage des modes d'occupation et des pratiques culturales anciennes?

2018

3 pages; National audience

1400 years of man-environment interactions and soil evolution in the Saint-Mont mountain (Remiremont, Vosges)

2021

International audience; The SolHoM(a) project aims at determining the degree of landscape anthropisation in the Fossard massif (Remiremont, Vosges, France) by estimating the impact of past human occupations on current soils. Nowadays, a forest covers this relatively inhospitable mountain (hard climate, steep slopes, acid soils ...), but some remains suggest human presence for at least 1400 years.The Saint-Mont is a variscan orogenic granitic summit (height 672m) with valuable preserved archaeological relics, located south of the Fossard. At the top was founded the monasterium Habendum (from the 7th century to the French Revolution), which potentially comes after a late-antic castrum.Further…