2016, November 21
Soil compaction and insect pollination modify impacts of croprotation on nitrogen fixation and yield.
Pollination and biological nitrogen fixation are key ecosystem services, but their contribution to agricultural production mightbe influenced by simplified crop rotation and soil compaction, two factors known to limit yield. In a greenhouse experiment,we investigated the combined effect of crop rotation, soil compaction, and insect pollination on yield formation and on thecontribution of biological fixation to nitrogen acquisition of faba bean. Seed yield was reduced under high soil compaction, andunder ley rotation management and it was enhanced by insect pollination. For plants grown in soil from the ley rotation, insectpollination increased individual seed weight by 50% suggesting a contribution to seed quality by pollination for crop grown insoils where nutrients are limiting yield. Crop monoculture and high soil compaction interactively reduced the contribution ofnitrogen fixation by 30%, suggesting that soil compaction exacerbates the negative effect of monoculture on nitrogen fixation.Overall the results revealed that interactive effects of management factors do affect nutrient acquisition. We provide evidencethat reduced soil quality affect the capacity of legumes to deliver key ecosystem services to the agroecosystem.
Reference: Audrey St-Martin and Riccardo Bommarco. Soil compaction and insect pollination modify impacts of croprotation on nitrogen fixation and yield. Basic and Applied Ecology 17 (2016) 617–626.
2016, October 4
Can above-ground ecosystem services compensate
for reduced fertilizer input and soil organic matter in
1. Above-ground and below-ground environmental conditions influence crop yield by pollination, pest pressure and resource supply. However, little is known about how interactions between these factors contribute to yield. Here, we used oilseed rape Brassica napus to test their effects on crop yield.
2. We exposed potted plants to all combinations of high and low levels of soil organic matter (SOM) and fertilizer supply, and placed all treatments at a variety of field sites representing a gradient in pollinator visitation rate and pest exposure. We determined the relative contribution of pollinators and pests, SOM and fertilizer supply to yield. We also tested whether SOM can moderate effects of fertilizer on yield and whether soil conditions influence the relationship between above-ground conditions and yield.
3. Increases in pollinator visitation rate and decreases in pest pressure enhanced yield more than increase in fertilizer supply. Although higher SOM content resulted in plants with more biomass and flowers, under our experimental conditions SOM neither enhanced yield, nor influenced effects of fertilizer, pollinators or pests on yield.
4. The relationships between yield, pollinator visitation rate and pest pressure did not depend on the level of fertilization, suggesting that the effects of fertilizer application and aboveground (dis)services on yield were additive. In contrast, pollinator visitation rate was more strongly related to yield at low pest pressure than at high pest pressure indicating trade-offs between above-ground services and disservices.
5. Synthesis and applications. Our results show that it is possible to increase oilseed rape yield by enhancing pollination, irrespective of supplying mineral fertilizer. Moreover, the fact that belowground
conditions did not alter the effect of above-ground conditions suggests that farmers may obtain even higher yields by maximizing both above-ground ecosystem services and external inputs. Further studies are needed to understand at which point the positive relationships between pollinator visitation and yield, as well as between fertilizer and yield, will level off. Considering above-ground and below-ground services and inputs in agro-ecosystems in conjunction is crucial in order to optimize external inputs for crop yield from an economic and ecological perspective.
Reference: Stijn van Gils, Wim H. van der Putten and David Kleijn. Can above-ground ecosystem services compensate for reduced fertilizer input and soil organic matter in annual crops? Journal of Applied Ecology 2016, 53, 1186–1194
2016, September 1
Soil management shapes ecosystem
service provision and trade-offs in
Agroecosystems are principally managed to maximize food provisioning
even if they receive a large array of supporting and regulating ecosystem
services (ESs). Hence, comprehensive studies investigating the effects of
local management and landscape composition on the provision of and
of conservation tillage, nitrogen fertilization and landscape composition
trade-offs between multiple ESs are urgently needed.We explored the effects
on six ESs (crop production, disease control, soil fertility, water quality
regulation, weed and pest control) in winter cereals. Conservation tillage
enhanced soil fertility and pest control, decreased water quality regulation
Fertilization only influenced crop production by increasing grain yield.
and weed control, without affecting crop production and disease control.
Landscape intensification reduced the provision of disease and pest control.
We also found tillage and landscape composition to interactively affect water
quality regulation and weed control. Under N fertilization, conventional
tillage resulted in more trade-offs between ESs than conservation tillage.
Our results demonstrate that soil management and landscape composition
affect the provision of several ESs and that soil management potentially
shapes the trade-offs between them.
Giovanni Tamburini, Serena De Simone, Maurizia Sigura, Francesco Boscutti and Lorenzo Marini. Soil management shapes ecosystem service provision and trade-offs in agricultural landscapes. 2016. Proc. R. Soc. B 283: 20161369.
2016, May 26
LIBERATION project featured in Horizon magazine:
‘Ecological intensification’ swaps pesticides for biodiversity.
While farmers often turn to pesticides and herbicides to get as much produce as possible from their land, there’s something new on the menu that could employ nature’s own resources instead.
2016, April 22
Policy Entry Points for Enabling Ecological Intensification and the EU Common Agriculture Policy (CAP)
The purpose of this document is to look at policy entry points for ecological intensification in the European Union’s Common Agricultural Policy (CAP) and other policies instruments at the national (Member States) and sub-national levels. The document explores also relevant challenges and barriers to building supporting policies for ecological intensification, and outlines a number of recommendations for those stakeholders that are its target audience – LIBERATION partner organizations, farmers and farming communities, policymakers working within the CAP and the private sector.
The key conclusions from the analysis of policy entry points at the EU, national and sub-national levels are that:
- While the CAP was not specifically designed to target ecological intensification, a number of field and farm-level measures that could respond to stronger prioritization on environmental impacts in agricultural production may already qualify under the AEM payment schemes or are potentially applicable under cross-compliance with the Statutory Management Requirements (SMRs);
- Above all, the challenge that most affect implementation of ecological intensification measures is the limited information available in terms of yield performance, profitability and reduced costs of inputs with respect to conventional approaches.
Reference: Arthur Getz Escudero (Cardiff University), Barbara Gemmill-Herren (FAO), David Colozza (FAO) and Benjamin Graeub (FAO). Policy Entry Points for Enabling Ecological Intensification and the EU Common Agriculture Policy (CAP). Oecologia, March 2016, Volume 180, Issue 3, pp 759–769
2016, April 12
Large‑scale pollination experiment demonstrates the importance
of insect pollination in winter oilseed rape.
Insect pollination, despite its potential to contribute
substantially to crop production, is not an integrated
part of agronomic planning. A major reason for this are
knowledge gaps in the contribution of pollinators to yield,
which partly result from difficulties in determining areabased
estimates of yield effects from insect pollination
under field conditions. We have experimentally manipulated
honey bee Apis mellifera densities at 43 oilseed rape
Brassica napus fields over 2 years in Scandinavia. Honey
bee hives were placed in 22 fields; an additional 21 fields
without large apiaries in the surrounding landscape were
selected as controls. Depending on the pollination system
in the parental generation, the B. napus cultivars in the crop
fields are classified as either open-pollinated or first-generation
hybrids, with both types being open-pollinated in
the generation of plants cultivated in the fields. Three cultivars
of each type were grown. We measured the activity
of flower-visiting insects during flowering and estimatedyields by harvesting with small combine harvesters. The addition of honey bee hives to the fields dramatically increased abundance of flower-visiting honey bees in those fields. Honey bees affected yield, but the effect depended on cultivar type (p = 0.04). Post-hoc analysis revealed that open-pollinated cultivars, but not hybrid cultivars, had 11% higher yields in fields with added honey bees than those grown in the control fields (p = 0.07). To our knowledge, this is the first whole-field study in replicated landscapes to assess the benefit of insect pollination in oilseed rape. Our results demonstrate that honey bees have the potential to increase oilseed rape yields, thereby emphasizing the importance of pollinator management for optimal cultivation of oilseed rape.
Reference: Sandra A. M. Lindström, Lina Herbertsson, Maj Rundlöf, Henrik G. Smith and Riccardo Bommarco. Large‑scale pollination experiment demonstrates the importance of insect pollination in winter oilseed rape. Oecologia March 2016, Volume 180, Issue 3, pp 759–769.
2016, January 27
The role of food retailers in improving resilience in global food supply.
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 en- courage 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 ap- propriate, 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 eco
system services at the landscape-scale.
Reference: Sarina Macfadyen, Jason M. Tylianakis, Deborah K. Letourneau, Tim G. Benton, Pablo Tittonell, Michael P. Perring, Carla Gómez-Creutzberg, András Báldi, John M. Holland, Linda Broadhurst, Kimiko Okabe, Anna R. Renwick, Barbara Gemmill-Herren, Henrik G. Smith. The role of food retailers in improving resilience in global food supply. 2016. Global Food Security
2015, November 26
Pollinator conservation — the difference between
managing for pollination services and preserving
Our review looks at pollinator conservation and highlights the
differences in approach between managing for pollination
services and preserving pollinator diversity. We argue that
ecosystem service management does not equal biodiversity
conservation, and that maintaining species diversity is crucial in
providing ecosystem resilience in the face of future
environmental change. Management and policy measures
therefore need to focus on species not just in human dominated
landscapes but need to benefit wider diversity of species
including those in specialised habitats. We argue that only by
adopting a holistic ecosystem approach we can ensure the
conservation and sustainable use of biodiversity and
ecosystem services in the long-term.
2015, October 16
The role of agri-environment schemes in
conservation and environmental management.
Over half of the European landscape is under agricultural management and has been formillennia.
Many species and ecosystems of conservation concern in Europe depend on agricultural management and
are showing ongoing declines. Agri-environment schemes (AES) are designed partly to address this. They are a
major source of nature conservation funding within the European Union (EU) and the highest conservation
expenditure in Europe.We reviewed the structure of current AES across Europe. Since a 2003 review questioned
the overall effectiveness of AES for biodiversity, there has been a plethora of case studies and meta-analyses
examining their effectiveness. Most syntheses demonstrate general increases in farmland biodiversity in
response to AES, with the size of the effect depending on the structure and management of the surrounding
landscape. This is important in the light of successive EU enlargement and ongoing reforms of AES. We
examined the change in effect size over time by merging the data sets of 3 recent meta-analyses and found
that schemes implemented after revision of the EU’s agri-environmental programs in 2007 were not more
effective than schemes implemented before revision. Furthermore, schemes aimed at areas out of production
(such as field margins and hedgerows) are more effective at enhancing species richness than those aimed
at productive areas (such as arable crops or grasslands). Outstanding research questions include whether
AES enhance ecosystem services, whether they are more effective in agriculturally marginal areas than in
intensively farmed areas, whether they are more or less cost-effective for farmland biodiversity than protected
areas, and how much their effectiveness is influenced by farmer training and advice? The general lesson
from the European experience is that AES can be effective for conserving wildlife on farmland, but they are
expensive and need to be carefully designed and targeted.
2015, October 16
Trait matching of flower visitors and crops predicts fruit set better than trait diversity.
1. Understanding the relationships among trait diversity, species diversity, and ecosystem functioning is essential for sustainable management. For functions comprising two trophic levels, trait matching between interacting partners should also drive functioning. However, the predictive ability of trait diversity and matching is unclear for most functions, particularly for crop pollination, where interacting partners did not necessarily co-evolve.
2. Worldwide, we collected data on traits of flower visitors and crops, visitation rates to crop flowers per insect species, and fruit set in 469 fields of 33 crop systems. Through hierarchical mixed-effects models we tested whether flower-visitor trait diversity and/or trait matching between flower visitors and crops improve the prediction of crop fruit set (functioning) beyond flower-visitor species diversity and abundance.
3. Flower-visitor trait diversity was positively related to fruit set, but surprisingly did not explain more variation than flower-visitor species diversity.
4. The best prediction of fruit set was obtained by matching traits of flower visitors (body size and mouthpart length) and crops (nectar accessibility of flowers) in addition to flower-visitor abundance, species richness, and species evenness. Fruit set increased with species richness, and more so in assemblages with high evenness, indicating that additional species of flower visitors contribute more to crop pollination when species abundances are similar.
5. Synthesis and applications. Despite contrasting floral traits for crops worldwide, only the abundance of a few pollinator species is commonly managed for greater yield. Our results suggest that the identification and enhancement of pollinator species with traits matching those of the focal crop, as well as the enhancement of pollinator richness and evenness, will increase crop yield beyond current practices. Furthermore, we show that field practitioners can predict and manage agroecosystems for pollination services based on knowledge of just a few traits that are known for a wide range of flower-visitor species.
Reference: Lucas A. Garibaldi, Ignasi Bartomeus, Riccardo Bommarco, Alexandra M. Klein, Saul A. Cunningham, Marcelo A. Aizen, Virginie Boreux, Michael P. D. Garratt, Luísa G. Carvalheiro, Claire Kremen, Carolina L. Morales, Christof Schüepp, Natacha P. Chacoff, Breno M. Freitas, Vesna Gagic, Andrea Holzschuh, Björn K. Klatt, Kristin M. Krewenka, Smitha Krishnan, Margaret M. Mayfield, Iris Motzke, Mark Otieno, Jessica Petersen, Simon G. Potts, Taylor H. Ricketts, Maj Rundlöf, Amber Sciligo, Palatty Allesh Sinu, Ingolf Steffan-Dewenter, Hisatomo Taki, Teja Tscharntke, Carlos H. Vergara, Blandina F. Viana, Michal Woyciechowski. Trait matching of flower visitors and crops predicts fruit set better than trait diversity. 2015. Journal of Applied Ecology. DOI: 10.1111/1365-2664.12530.
2015, October 8
Wildlife-friendly farming increases crop
yield: evidence for ecological
Ecological intensification has been promoted as a means to achieve environmentally sustainable increases in crop yields by enhancing ecosystem functions that regulate and support production. There is, however, little direct evidence of yield benefits from ecological intensification on commercial farms growing globally important foodstuffs (grains, oilseeds and pulses). We replicated two treatments removing 3 or 8% of land at the field edge from production to create wildlife habitat in 50–60 ha patches over a 900 ha commercial arable farm in central England, and compared these to a business as usual control (no land removed). In the control fields, crop yields were reduced by as much as 38% at the field edge. Habitat
creation in these lower yielding areas led to increased yield in the cropped areas of the fields, and this positive effect became more pronounced over 6 years. As a consequence, yields at the field scale were maintained—and, indeed, enhanced for some crops—despite the loss of cropland for habitat creation. These results suggested that over a 5-year crop rotation, there would be no adverse impact on overall yield in terms of monetary value or nutritional energy. This study provides a clear demonstration that wildlife-friendly management which supports ecosystem services is compatible with, and can even increase, crop yields.
2015, September 3
Modeling pollinating bee visitation rates in heterogeneous landscapes from foraging theory.
Pollination by bees is important for food production. Recent concerns about the declines of both domestic and wild bees, calls for measures to promote wild pollinator populations in farmland. However, to be able to efficiently promote and prioritize between measures that benefit pollinators, such as modified land use, agri-environment schemes, or specific conservation measures, it is important to have a tool that accurately predicts how bees use landscapes and respond to such measures. In this paper we compare an existing model for predicting pollination (the “Lonsdorf model”), with an extension of a general model for habitat use of central place foragers (the “CPF model”). The Lonsdorf model has been shown to perform relatively well in simple landscapes, but not in complex landscapes. We hypothesized that this was because it lacks a behavioral component, assuming instead that bees in essence diffuse out from the nest into the landscape. By adding a behavioral component, the CPF model in contrast assumes that bees only use those parts of the landscape that enhances their fitness, completely avoiding foraging in other parts of the landscape. Because foraging is directed toward the most rewarding foraging habitat patches as determined by quality and distance, foraging habitat will include a wide range of forage qualities close to the nest, but a much narrower range farther away. We generate predictions for both simple and complex hypothetical landscapes, to illustrate the effect of including the behavioral rule, and for real landscapes. In the real landscapes the models give similar predictions for visitation rates in simple landscapes, but more different predictions in heterogeneous landscapes. We also analyze the consequences of introducing hedgerows near a mass-flowering crop field under each model. The Lonsdorf model predicts that any habitat improvement will enhance pollination of the crop. In contrast, the CPF model predicts that the hedgerow must provide good nesting sites, and not just foraging opportunities, for it to benefit pollination of the crop, because good forage quality alone may drain bees away from the field. Our model can be used to optimize pollinator mitigation measures in real landscapes.
Reference: Ola Olssona, Arvid Bolina, Henrik G. Smith, Eric V. Lonsdorf. Modeling pollinating bee visitation rates in heterogeneouslandscapes from foraging theory. Ecological Modelling 316 (2015) 133–143
2015, July 7
Organic farming enhances parasitoid diversity at the
local and landscape scales.
1. The magnitude of the benefits derived from organic farming within contrasting managed landscapes remains unclear and, in particular, the potential scale-dependent response of insect parasitoids is relatively unexplored. Identifying the scale at which parasitoids are affected by organic farming will be an important step to enhance their conservation.
2. We sampled tachinid parasitoids at the centre and margin of arable and grassland fields on paired organic and conventional farms located in landscapes with different proportions of organic land. A total of 192 fields were sampled in two biogeographical regions of the UK.
3. We found that the positive effect of organic farming on tachinid parasitoid diversity can be observed at multiple spatial scales. At the local scale, we found higher abundance and species richness of tachinid parasitoids on organic than on conventional farms and on field marginsthan on field centres. At the landscape scale, the diversity of tachinids was higher in landscapes with higher proportions of organic land. At both scales, the positive effect of organic farming was clear for arable fields, while it was almost neutral for grasslands.
4. Synthesis and applications. Any attempt to enhance parasitoid diversity in agricultural landscapes needs to consider the local management in relation to the habitat type, location within the field and agricultural management in the surrounding landscape. To restore parasitoid diversity, the promotion of organic agriculture should aim to increase both the total extent of organic farming and the connectivity of individual farms. As the benefits of organic farming to biodiversity clearly spread beyond individual farm boundaries, any assessment of organic farming should consider these positive externalities.
2015, June 29
Landscape composition affects parasitoid spillover.
The intensification of agriculture has led to a severe simplification of agricultural landscapes, resulting in
a marked reduction in the diversity of insect natural enemies. However, how this simplification shapes
the movement of insect parasitoids between crop and non-crop habitats (i.e., spillover) is still unclear. We examined the potential spillover of tachinid parasitoids from semi-natural habitats into apple orchards
across different landscapes. We sampled commercial apple orchards localized in three landscape types
(forest-, grassland- or apple-dominated landscapes) to first evaluate if landscape composition affects the
local species richness in apple orchards. Second, we tested whether the contribution of forest and
grassland habitats to the local tachinid community composition of apple orchards changes according to
landscape composition. We found that landscape composition did not affect local tachinid species
richness in apple orchards, while it affected the species spillover. Independently of the landscape, we
found highly nested communities of tachinids between apple orchards and forest habitats suggesting a
strong spillover of tachinids between these habitats. In contrast, tachinids in apple orchards were nested
with grassland habitats only in landscapes dominated by apple orchards. Our results have important
implications for the conservation of insect parasitoids in agricultural landscapes, as the spillover of
species in the crop can be affected by the type and the area of semi-natural habitats in the surrounding
Reference: Diego J. Inclán, Pierfilippo Cerretti, Lorenzo Marini (2015) Landscape composition affects parasitoid spillover. Agriculture, Ecosystems & Environment, Volume 208, 1 October 2015, Pages 48–54
2015, June 17
Delivery of crop pollination services is an insufficient argument for wild pollinator conservation.
There is compelling evidence that more diverse ecosystems deliver greater benefits to people, and these
ecosystem services have become a key argument for biodiversity conservation. However, it is unclear
how much biodiversity is needed to deliver ecosystem services in a cost-effective way. Here we show
that, while the contribution of wild bees to crop production is significant, service delivery is restricted to
a limited subset of all known bee species. Across crops, years and biogeographical regions, crop-visiting
wild bee communities are dominated by a small number of common species, and threatened species
are rarely observed on crops. Dominant crop pollinators persist under agricultural expansion and many
are easily enhanced by simple conservation measures, suggesting that cost-effective management
strategies to promote crop pollination should target a different set of species than management
strategies to promote threatened bees. Conserving the biological diversity of bees therefore requires
more than just ecosystem-service-based arguments.
Reference: David Kleijn, Rachael Winfree, Ignasi Bartomeus, Luísa G Carvalheiro, Mickaël Henry, Rufus Isaacs, Alexandra-Maria Klein, Claire Kremen, Leithen K M'Gonigle, Romina Rader, Taylor H Ricketts, Neal M Williams, Nancy Lee Adamson, John S Ascher, András Báldi, Péter Batáry, Faye Benjamin, Jacobus C Biesmeijer, Eleanor J Blitzer, Riccardo Bommarco, Mariëtte R Brand, Vincent Bretagnolle, Lindsey Button, Daniel P Cariveau, Rémy Chifflet, Jonathan F Colville, Bryan N Danforth, Elizabeth Elle, Michael P.D. Garratt, Felix Herzog, Andrea Holzschuh, Brad G Howlett, Frank Jauker, Shalene Jha, Eva Knop, Kristin M Krewenka, Violette Le Féon, Yael Mandelik, Emily A May, Mia G Park, Gideon Pisanty, Menno Reemer, Verena Riedinger, Orianne Rollin, Maj Rundlöf, Hillary S Sardiñas, Jeroen Scheper, Amber R Sciligo, Henrik G Smith, Ingolf Steffan-Dewenter, Robbin Thorp, Teja Tscharntke, Jort Verhulst, Blandina F Viana, Bernard E Vaissière, Ruan Veldtman, Catrin Westphal & Simon G Potts (2015) Delivery of crop pollination services is an insufficient argument for wild pollinator conservation. Nature Communications 6, Article number: 7414 doi:10.1038/ncomms8414
2015, April 16
Crop management modifies the benefits of insect pollination in oilseed rape.
In a factorial field plot experiment, high and low levels of inorganic nitrogen and of insect pollinators
visiting the crop were manipulated and their combined effects on oilseed rape yield were quantified. A
third factor was also included, testing whether different cultivars responded differently to the tested
factors. Insect pollination was required to reach high yield and seed quality (oil content). Final benefits of
pollination service were, however, greatly modified by cultivar, where the seed yield of the openpollinated cultivar largely depended on insect pollination whereas the two hybrid cultivars did not. A
near significant interaction between nitrogen input and insect pollination was also found, i.e. benefits to
crop yield from insect pollination seemed to increase with decreased nitrogen levels. The differential
response of the three cultivars suggested opportunities to use cultivars that are less dependent on insect
pollination in landscapes where this service has been deteriorated. Increased access of nitrogen seems to
partly compensate yield losses from poor insect pollination. Integrating conservation, environmental and
agronomic sciences is therefore crucial to sustain agriculture productions through optimized management of agronomic inputs and biodiversity-based ecosystem services.
2015, January 12
Testing scale-dependent effects of semi-natural habitats on farmland biodiversity.
The effectiveness of conservation interventions for maximizing biodiversity benefits from agri-environment schemes (AESs) is expected to depend on the quantity of semi-natural habitats in the surrounding landscape. To verify this hypothesis, we developed a hierarchical sampling design to assess the effects of field boundary type and cover of semi-natural habitats in the landscape at two nested spatial scales. We sampled three types of field boundaries with increasing structural complexity (grass margin - simple hedgerow - complex hedgerow) in paired landscapes with presence or absence of semi-natural habitats (radius 0.5 km), that in turn, were nested within 15 areas with different proportions of semi-natural habitats at a larger spatial scale (10 × 10 km). Overall, 90 field boundaries were sampled across a Mediterranean region (NE Italy). We considered species richness response across three different taxonomic groups: vascular plants, butterflies, and tachinid flies. No interactions between type of field boundary and surrounding landscape were found at either 0.5 and 10 km indicating that the quality of field boundary had the same effect irrespective of the cover of semi-natural habitats. At the local scale, extended-width grass margins yielded higher plant species richness, while hedgerows yielded higher species richness of butterflies and tachinids. At the 0.5 km landscape scale, the effect of the proportion of semi-natural habitats was neutral for plants and tachinids, while butterflies were positively related to the proportion of forest. At the 10 km landscape scale, only butterflies responded positively to the proportion of semi-natural habitats. Our study confirmed the importance of testing multiple scales when considering species from different taxa and with different mobility. We showed that the quality of field boundaries at the local scale was an important factor in enhancing farmland biodiversity. For butterflies, AESs should focus particular attention on preservation of forest patches in agricultural landscapes within 0.5 km as well as the conservation of semi-natural habitats at a wider landscape scale.
2014, December 11
Diversification practices reduce organic
to conventional yield gap.
Agriculture today places great strains on biodiversity, soils, water and the
atmosphere, and these strains will be exacerbated if current trends in population
growth, meat and energy consumption, and food waste continue.
Thus, farming systems that are both highly productive and minimize environmental
harms are critically needed. How organic agriculture may contribute to
world food production has been subject to vigorous debate over the past
decade. Here, we revisit this topic comparing organic and conventional
yields with a new meta-dataset three times larger than previously used (115
studies containing more than 1000 observations) and a new hierarchical
analytical framework that can better account for the heterogeneity and structure
in the data. We find organic yields are only 19.2% (+3.7%) lower than
conventional yields, a smaller yield gap than previous estimates. More importantly,
we find entirely different effects of crop types and management
practices on the yield gap compared with previous studies. For example, we
found no significant differences in yields for leguminous versus non-leguminous
crops, perennials versus annuals or developed versus developing
countries. Instead, we found the novel result that two agricultural diversification
practices, multi-cropping and crop rotations, substantially reduce the
yield gap (to 9+4% and 8+5%, respectively) when the methods were
applied in only organic systems. These promising results, based on robust
analysis of a larger meta-dataset, suggest that appropriate investment in agroecological
research to improve organic management systems could greatly
reduce or eliminate the yield gap for some crops or regions.
Reference: Lauren C. Ponisio, Leithen K. M'Gonigle, Kevi C. Mace, Jenny Palomino, Perry de Valpine, Claire Kremen (2015) Diversification practices reduce organic to conventional yield gap. Proceedings of the Royal Society of London B: Biological Sciences; DOI: 10.1098/rspb.2014.1396.Published 10 December 2014
2014, November 28
Museum specimens reveal loss of pollen host plants as key factor driving wild bee decline in The Netherlands.
Growing concern about bee declines and associated loss of pollination services has increased the urgency to identify the underlying causes. So far, the identification of the key drivers of decline of bee populations has largely been based on speculation. We assessed the relative importance of a range of proposed factors responsible for wild bee decline and show that loss of preferred host plant species is one of the main factors associated with the decline of bee populations in The Netherlands. Interestingly, species foraging on crop plant families have stable or increasing populations. These results indicate that mitigation strategies for loss of wild bees will only be effective if they target the specific host plants of declining bee species.
Reference: Jeroen Scheper, Menno Reemer, Ruud van Kats, Wim A. Ozinga, Giel T. J. van der Linden, Joop H. J. Schaminée, Henk Siepel and David Kleijn (2014). Museum specimens reveal loss of pollen host plants as key factor driving wild bee decline in The Netherlands. PNAS 2014 ; published ahead of print November 24, 2014, doi:10.1073/pnas.1412973111
2014, June 5
EU agricultural reform fails on biodiversity.
In December 2013, the European Union (EU) enacted the reformed Common Agricultural Policy (CAP) for 2014–2020, allocating almost 40% of the EU's budget and influencing management of half of its terrestrial area. Many EU politicians are announcing the new CAP as “greener,” but the new environmental prescriptions are so diluted that they are unlikely to benefit biodiversity. Individual Member States (MSs), however, can still use flexibility granted by the new CAP to design national plans to protect farmland habitats and species and to ensure long-term provision of ecosystem services.
Reference: Pe’er, G., Dicks, L.V., Visconti, P., Arlettaz, R., Báldi, A., Benton, T.G., Collins, S., Dieterich, M., Gregory, R.D., Hartig, F., Henle, K., Hobson, P.R., Kleijn, D., Neumann, R.K., Robijns, T., Schmidt, J., Shwartz, A., Sutherland, W.J., Turbe, A., Wulf, F. & Scott, A.V. (2014). EU agricultural reform fails on biodiversity. Science, 344, 1090-1092.
2014, April 4
Glossary of terms on ecosystem services in agriculture published by FAO.
If you have any questions about terminology used in the debate on ecological intensification you can look it up here:
2014, April 3
LIBERATION Community of Practice on Ecological Intensification launched.
As part of the Liberation project the FAO, with its partner the Platform for Agrobiodiversity Research (PAR) have recently launched the Community of Practice on Ecological Intensification. The information-sharing platform aims to animate a community of practice amongst specialists in fields relevant to ecological intensification. You are warmly invited to visit the website: http://agrobiodiversityplatform.org/liberation/
2014, January 6
Pollination is known to improve yields of many crops, but comprehensive benefits, including crop quality and market value, remain unknown. Klatt et al. (2014) set up a field experiment with nine strawberry varieties and assessed the influence of self, wind en bee pollination on strawberry fruits, using exclusion treatments. The showed bee pollination to improve fruit quantity as well as quality (shape, colour, firmness, sugar-acid ratio) and thereby market value. Bee pollination resulted in longer shelf life, reducing fruit loss by at least 11%. These results demonstrate bee pollination to be a hitherto underestimated but vital and economically important determinant of fruit quality.
Reference: Klatt BK, Holzschuh A, Westphal C, Clough Y, Smit I, Pawelzik E, Tscharntke T. (2014). Bee pollination improves crop quality, shelf life and commercial value. Proc. R. Soc. B. 281: 20132440.
2013, September 19
As part of the reform of the common agricultural policy the European Commission proposed to make more diverse crop rotations conditional for receiving agricultural subsidies. Subsequent negotiations significantly watered down these proposals but a recent meta-analyses suggests that the original proposal would have been a step in the right direction from the perspective of farming efficiency as well as biodiversity. “Adding one or more crops in rotation to a monoculture increased total soil carbon by 3.6% and total nitrogen by 5.3%. When rotations included a cover crop (i.e. crops that are not harvested but produced to enrich the soil and capture inorganic nitrogen), total carbon increased by 8.5% and total nitrogen 12.8%.” The authors conclude that “Crop rotations, especially those that include cover crops, sustain soil quality and productivity by enhancing soil C, N and microbial biomass, making them a cornerstone for sustainable agroecosystems.”
Reference: McDaniel,M.D. Tiemann, L.K. & Grandy A.S. (2014). In press. Does agriculturalcrop diversity enhance soil microbial biomass and organic matter dynamics? A meta-analysis. Ecological Applications. http://dx.doi.org/10.1890/13-0616.1
2013, September 10
“Biodiversity counteracts potential adverse effects of climate change on pollination service delivery. Climate change might negatively affect agricultural production by causing a mismatch between the flowering time of insect-pollinated crops and the flight period of pollinating insects. A recent study on apple found that high levels of biodiversity buffer the negative effects of species-specific phenological shifts and maintain pollination synchrony at the community level in this crop. This was caused by complementarity among bee species’ activity periods.”
Reference: Bartomeus, I., Park, M.G., Gibbs, J., Danforth, B.N., Lakso, A.N. & Winfree, R. (2014). Biodiversity ensures plant–pollinator phenological synchrony against climate change. Ecology Letters, doi: 10.1111/ele.12170.
2013, July 11
2013, July 4
“Despite the widespread concern about the fate of pollinators and the ecosystem services they deliver, we still have surprisingly scarce scientific data on the magnitude of pollinator declines and its actual contribution to crop pollination and food security. Using recently published data Bartomeus and Winfree show that bee species that are currently delivering most of the ecosystem services (i.e. crop pollination) are not among the species showing declining trends, but rather appear to thrive in human-dominated landscapes.”
2013, June 6
“How can we meet the rising demands for agricultural products but avoid large-scale environmental degradation of the countryside? A new paper presenting the framework of ecological intensification highlights potential strategies avenues and points avenues worth exploring. The basic principle is to mobilize ecosystem services such as nutrient cycling, pollination and pest control to augment and/or substitute conventional practices. The paper furthermore identifies knowledge gaps that prevent rapid adoption of this approach by the farming community. Many of these knowledge gaps will be addressed in the LIBERATION project.”