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Bioindication of ecological variables such as humidity, temperature or pH by ecological indicator values of plants is a powerful tool for research in plant ecology, e.g. to detect early vegetation changes. Here, we provide a data set of ecological indicator values including niche width for an entire regional flora. We used an extensive data-base with floristic relevés from Southern France to recalibrate indicator values for light (L), temperature (T), continentality (K), air humidity (A), soil moisture (F), pH (R), productivity (N), soil texture (G), soil organic matter content (O) and salinity (S). Values were recalibrated using average values from co-occurring plants, enabling to develop indicator values for species not yet evaluated previously. Recalibrated values are on a continuous scale and we add standard deviation, median, first and third quartile for each indicator value. Linear regression of average indicator values against measured factors showed higher correlation with recalibrated values compared to original indicator values for temperature, pH and nitrogen, and comparable R2 for moisture. Individual indicator systems performed better than a combination and applying different weighting procedures demonstrated the usefulness of inverse variance. We further illustrate graphically how recalibrated values and niche width increase ecological knowledge on plants. [ABSTRACT FROM AUTHOR]

Consumption by animals remains one of the key points to assess the effectiveness of grazing impacts in woodland for increasing understorey plant diversity. To limit the spread of the brambles and restore understorey plant diversity on an artificial embankment an original system of clearings connected by paths was created by mechanically crushing brambles and allowing them to be grazed by rustic goats. The analysis of the indices of consumption of bramble under GIS has been used to provide an estimation of the volume ingested and an estimation of the effectiveness of the goats. The impacts of three different managements (goat grazing, brush clearing and grazing, clearing and exclusion of grazing) and control without management were then tested during a three-year period. The monitoring of the vegetation on permanent plots provided evidence that goat grazing significantly increased in the short term the species-richness and heterogeneity of herbaceous plants communities, in complement with prior clearing. Thus, the objectives of the managers to open up the area and reduce the bramble cover were achieved, but the prior introduction of goats and the installation of mobile enclosures would be advisable in order to ensure the sustainability of these measures on plant diversity in the long term. [ABSTRACT FROM AUTHOR]

Highlights: [•] Four ecological engineering techniques were used to restore a Mediterranean steppe and were monitored after 3 years. [•] Covering species seeding decreased grass cover, too dense on the rehabilitated area. [•] Topsoil removal decreased vegetation cover and increased species-richness. [•] Hay transfer increased target species richness but with a few grasses dominating. [•] Soil transfer showed the best results with plant community close to the reference but still with some differences. [•] Despite positive results, no techniques fully restored the steppe in the short term. [ABSTRACT FROM AUTHOR]

This study analysed specific features of the spatial distribution of a global population of arthropods in an experimental orchard of pear trees, Pyrus communis (L.), in southern France. Insect fauna was sampled by regular beating of the 210 trees in the experimental orchard from spring to autumn in three consecutive years (2004–2006). This orchard, where no chemical treatments had been applied since 2000, is bordered to the north by a mixed hedge, to the south by a cypress hedge of Cupressus sempervirens (L.), and to the east and west by other crops. Statistical analyses of climatic variables comparing the 3 years showed no differences with respect to rainfall, temperature or wind variables during psyllid proliferation periods. However, statistical spatial analyses demonstrated a hedge effect on local ecological variables, such as population abundance, species richness and the Shannon diversity index, in a zone close to the mixed hedge, by comparison with zones close to other margins of the orchard. This spatial distribution exhibited temporal stability and pointed to two distinct zones: one unprotected and one protected by the mixed hedge from the Mistral wind. The first zone contained a population of psyllids that was significantly larger than that in the protected zone, which harboured a great majority of beneficial insects. This spatial stability over 3 years suggested in particular that climatic factors were related to psyllids, while spatial factors, such as distance from the mixed hedge, were related to beneficial insects. In the light of these results, we concluded as to the strong potential role that hedges could play in reducing crop pest populations. [Copyright &y& Elsevier]