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Macfadyen S.,CSIRO | Tylianakis J.M.,University of Canterbury | Tylianakis J.M.,Imperial College London | Letourneau D.K.,University of California at Santa Cruz | And 12 more authors.
Global Food Security | Year: 2015

We urgently need a more resilient food supply system that is robust enough to absorb and recover quickly from shocks, and to continuously provide food in the face of significant threats. The simplified global food supply chain we currently rely upon exacerbates threats to supply and is unstable. Much attention has been given to how producers can maximise yield, but less attention has been given to other stakeholders in the supply chain. Increasingly, transnational food retailers (supermarkets) occupy a critical point in the chain, which makes them highly sensitive to variability in supply, and able to encourage change of practice across large areas. We contend that the concentration in the chain down to a few retailers in each country provides an opportunity to increase resilience of future supply given appropriate, scale-dependent interventions. We make ten recommendations aimed at reducing variability in supply that can be driven by retailers (although some of the interventions will be implemented by producers). Importantly, resilience in our food supply requires the restoration and expansion of ecosystem services at the landscape-scale. © 2016.

Boros G.,Lendulet Ecosystem Services Research Group | Dozsa-Farkas K.,Eotvos Lorand University
Zootaxa | Year: 2015

We give descriptions of three new Fridericia species (Enchytraeidae, Oligochaeta) from Transylvania, Romania. Fridericia transylvanica sp. n. is a large-sized worm with a maximum of 4 chaetae per bundle. The spermathecae are separate entally and have two sac-like diverticula bent distad with the ampulla forming a common U-shaped sperm-containing chamber. The species was found not only in the Transylvanian Plateau but also in different regions of the Carpathians in Romania and Serbia. Fridericia gyromonodactyla sp. n. is medium-sized with a maximum of 3 chaetae per bundle. There are only four pairs of preclitellar nephridia. The spermathecal ectal duct is contractile and shorter than the body diameter; each ampulla has only one diverticulum, elongate and coiled, and there is one sessile gland at the orifice. Fridericia longeaurita sp.n. is large-sized with 4(5) chaetae per preclitellar bundle but only two or one in postclitellar bundles. The spermathecal ectal duct is shorter than the body diameter, with one small and sessile ectal gland at the orifice. Each ampulla has two long, ear-shaped, and sac-like diverticula. None of the three species were rare at the sites where they occurred. © 2015 Magnolia Press.

Kovacs-Hostyanszki A.,Lendulet Ecosystem Services Research Group | Kovacs-Hostyanszki A.,University of Gottingen | Haenke S.,University of Gottingen | Batary P.,University of Gottingen | And 6 more authors.
Ecological Applications | Year: 2013

Landscape-wide mass-flowering of oilseed rape (canola Brassica napus) can considerably affect wild bee communities and pollination success of wild plants. We aimed to assess the impact of oilseed rape on the pollination of wild plants and bee abundance during and after oilseed-rape bloom, including effects on crop-noncrop spillover at landscape and adjacentfield scales. We focused on two shrub species (hawthorn Crataegus spp., dog rose Rosa canina) and adjacent herb flowering in forest edges, connected hedges, and isolated hedges in Lower Saxony, Germany. We selected 35 landscape circles of 1 km radius, differing in the amount of oilseed rape; 18 were adjacent to oilseed rape and 17 to cereal fields, and we quantified bee density via pan traps at all sites. Adjacent oilseed rape positively affected fruit mass and seed number per fruit of simultaneously flowering hawthorn (no effect on dog rose, which flowers after the oilseed rape bloom). At the landscape scale, oilseed rape had a negative effect on bumble bee density in the hedges during flowering due to dilution of pollinators per unit area and the consequently intensified competition between oilseed rape and wild shrubs, but a positive effect after flowering when bees moved to the hedges, which still provided resources. In contrast, positive landscape-scale effects of oilseed rape were found throughout the season in forest edges, suggesting that edges support nesting activity and enhanced food resources. Our results show that oilseed rape effects on bee abundances and pollination success in seminatural habitats depend on the spatial and temporal scale considered and on the habitat type, the wild plant species, and the time of crop flowering. These scale-dependent positive and negative effects should be considered in evaluations of landscape-scale configuration and composition of crops. Food resources provided by mass-flowering crops should be most beneficial for landscape-wide enhancement of wild bee populations if seminatural habitats are available, providing (1) nesting resources and (2) continuous flowering resources during the season.© 2013 by the Ecological Society of America.

Fenesi A.,Debrecen University | Fenesi A.,Babes - Bolyai University | Vagasi C.I.,Babes - Bolyai University | Vagasi C.I.,Debrecen University | And 7 more authors.
Basic and Applied Ecology | Year: 2015

Secondary succession in former arable fields (i.e. old fields) might be altered by the colonization of invasive alien species, with possible community-wide impacts, hindering the ability of old fields to become species-rich communities. However, the effects of invasive species on local communities have rarely been addressed in the light of secondary succession. Therefore, we studied the impact of the highly invasive Solidago canadensis on plant and pollinator communities along a gradient of invasion severity in old fields with different ages (1-20 years since last ploughing) in Southern Transylvania, Romania. We asked whether the invasion of S. canadensis causes shifts in (1) the composition and diversity of plant communities, and (2) pollinator communities along the successional gradient. Further, we asked (3) to what extent the presence of S. canadensis affected flower visitation of native plant species by pollinators. According to our results, the invasion reduced the native plant species richness throughout succession, although the most profound negative effect on plant diversity and vegetation naturalness was exerted in older successional communities. The invasion of S. canadensis had a negative effect on the abundance of bees irrespective of the old field age; however, there was no similar negative effect on hoverflies. Native flowers experienced reduced visitation by wild bees, honey bees and hoverflies due to the augmented presence of S. canadensis. Therefore, the invasion of this perennial plant species diverts the trajectory of vegetation succession, alters the mutualistic links between the native elements of these old fields, and causes a non-desired alternative stable states to be installed. © 2015 Gesellschaft für Ökologie.

Schneider M.K.,Institute for Sustainability science | Luscher G.,Institute for Sustainability science | Luscher G.,University of Zurich | Jeanneret P.,Institute for Sustainability science | And 40 more authors.
Nature Communications | Year: 2014

Organic farming is promoted to reduce environmental impacts of agriculture, but surprisingly little is known about its effects at the farm level, the primary unit of decision making. Here we report the effects of organic farming on species diversity at the field, farm and regional levels by sampling plants, earthworms, spiders and bees in 1470 fields of 205 randomly selected organic and nonorganic farms in twelve European and African regions. Species richness is, on average, 10.5% higher in organic than nonorganic production fields, with highest gains in intensive arable fields (around +45%). Gains to species richness are partly caused by higher organism abundance and are common in plants and bees but intermittent in earthworms and spiders. Average gains are marginal +4.6% at the farm and +3.1% at the regional level, even in intensive arable regions. Additional, targeted measures are therefore needed to fulfil the commitment of organic farming to benefit farmland biodiversity. © 2014 Macmillan Publishers Limited. All rights reserved.

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