Impacts of roads on bird species richness: A meta-analysis considering road types, habitats and feeding guilds

Roadsides can harbour remarkable biodiversity; thus, they are increasingly considered as habitats with potential for conservation value. To improve construction and management of roadside habitats with positive effects on biodiversity, we require a quantitative understanding of important influential factors that drive both positive and negative effects of roads. We conducted meta-analyses to assess road effects on bird communities. We specifically tested how the relationship between roads and bird richness varies when considering road type, habitat characteristics and feeding guild association. Overall, bird richness was similar in road habitats compared to non-road habitats, however, the two apparently differ in species composition. Bird richness was lowered by road presence in areas with denser tree cover but did not differ according to road type. Richness differences between habitats with and without roads further depended on primary diet of species, and richness of omnivores was positively affected by road presence. We conclude that impacts of roads on bird richness are highly context-dependent, and planners should carefully evaluate road habitats on a case by case basis. This emphasizes the need for further studies that explicitly test for differences in species composition and abundance, to disentangle contexts where a road will negatively affect bird communities, and where it will not

Bioavailability of Macro and Micronutrients Across Global Topsoils: Main Drivers and Global Change Impacts

Understanding the chemical composition of our planet\u27s crust was one of the biggest questions of the 20th century. More than 100 years later, we are still far from understanding the global patterns in the bioavailability and spatial coupling of elements in topsoils worldwide, despite their importance for the productivity and functioning of terrestrial ecosystems. Here, we measured the bioavailability and coupling of thirteen macro- and micronutrients and phytotoxic elements in topsoils (3–8 cm) from a range of terrestrial ecosystems across all continents (∼10,000 observations) and in response to global change manipulations (∼5,000 observations). For this, we incubated between 1 and 4 pairs of anionic and cationic exchange membranes per site for a mean period of 53 days. The most bioavailable elements (Ca, Mg, and K) were also amongst the most abundant in the crust. Patterns of bioavailability were biome-dependent and controlled by soil properties such as pH, organic matter content and texture, plant cover, and climate. However, global change simulations resulted in important alterations in the bioavailability of elements. Elements were highly coupled, and coupling was predictable by the atomic properties of elements, particularly mass, mass to charge ratio, and second ionization energy. Deviations from the predictable coupling-atomic mass relationship were attributed to global change and agriculture. Our work illustrates the tight links between the bioavailability and coupling of topsoil elements and environmental context, human activities, and atomic properties of elements, thus deeply enhancing our integrated understanding of the biogeochemical connections that underlie the productivity and functioning of terrestrial ecosystems in a changing world

Intensify production, transform biomass to energy and novel goods and protect soils in Europe (INTENSE): Progress in year 2

ACTIInternational audienceThe European INTENSE project is responding to three “Great Challenges”: global food security, use of renewable raw materials and production of energy from biomass. Its contributes to reconvert poor, abandoned and polluted lands, e.g. grassland, set aside land, brownfields, and other marginal lands, into high, sustainable crop production. INTENSE sites are located throughout Europe from Spain in the south up to Norway in the north. Regarding precision agriculture, modeling tools and soil amendments, field plots are assessed using unmanned aerial vehicles and data crossed with those from crop production and soil microbial communities. This provides information on field heterogeneity to adapt soil management, seeding, fertilizing, and fungicide and herbicide application, allowing site-specific farming. At the Martlhof farm, Germany, increase in photosynthetic activity of barley was observed after incorporation of digested pig manure (solid fraction alone and with biochar) and compost although N uptake was similar. At Buendia and Casasana, Spain, barley plots with mineral N combined with compost pellets and biochar showed increased GNDVI (i.e. (NIR – green)/(NIR + green). Field data and image spectroscopy evidenced differences across plots, cultivars, plant performance and health. At Polish sites, compost combined with mineral N increased barley and maize yields. Suitable production systems are developed and implemented for land amelioration in complex degradation situations. At Martlhof, chestnut wood chips are pyrolysed to produce and use biochar. Extensive livestock farming is transformed to ecological intensive farming including livestock with monogastric animals, intercropping (Fabaceae), agroforestry, terraforming, and increased biodiversity (landscape ecology). Soil nutrients and biological functionality (FDA hydrolysis, community-level physiological profiling, and microbial DNA extractions) are analyzed at the beginning and after each growing season, showing high nutrient turnover, and increase in soil N and P contents. Organic amendments more influence overall microbial activity than functional diversity. Overall, the more organic matter, the higher the microbial activity. At French sites, long-term phytomanagement of contaminated soils with high yielding crops and short rotation coppices, combined with soil amendments, improved soil fertility, C sequestration, can stimulate microbial activity, and limited pollutant linkages. Weed control, reduced invasive vegetation, pest control, effect of soil mycorrhizae on nutrient cycling, and shelter belts are investigated. At Spanish sites, farming systems can be adapted by limiting wind erosion and water runoff, shaping stony fields, tree planting, soil amendment, winter crops and intercropping. At the farm level, environmental education, direct marketing, and (bio)energy production can add value

Bioavailability of macro and micronutrients across global topsoils:Main drivers and global change impacts

Understanding the chemical composition of our planet's crust was one of the biggest questions of the 20th century. More than 100 years later, we are still far from understanding the global patterns in the bioavailability and spatial coupling of elements in topsoils worldwide, despite their importance for the productivity and functioning of terrestrial ecosystems. Here, we measured the bioavailability and coupling of thirteen macro‐ and micronutrients and phytotoxic elements in topsoils (3–8 cm) from a range of terrestrial ecosystems across all continents (∼10,000 observations) and in response to global change manipulations (∼5,000 observations). For this, we incubated between 1 and 4 pairs of anionic and cationic exchange membranes per site for a mean period of 53 days. The most bioavailable elements (Ca, Mg, and K) were also amongst the most abundant in the crust. Patterns of bioavailability were biome‐dependent and controlled by soil properties such as pH, organic matter content and texture, plant cover, and climate. However, global change simulations resulted in important alterations in the bioavailability of elements. Elements were highly coupled, and coupling was predictable by the atomic properties of elements, particularly mass, mass to charge ratio, and second ionization energy. Deviations from the predictable coupling‐atomic mass relationship were attributed to global change and agriculture. Our work illustrates the tight links between the bioavailability and coupling of topsoil elements and environmental context, human activities, and atomic properties of elements, thus deeply enhancing our integrated understanding of the biogeochemical connections that underlie the productivity and functioning of terrestrial ecosystems in a changing world