Effects of Flower-Enriched Ecological Focus Areas on Functional Diversity Across Scales

Ecological Focus Areas (EFAs) to benefit biodiversity became mandatory in intensively farmed landscapes after the reform of the European Common Agricultural Policy (CAP) in 2013. The implementation of EFAs as uncropped field margins has been criticized as ineffective but created a window of opportunity to test if augmenting them with annual flower strips can benefit biodiversity. In this study, we investigated if annual flower strips on EFAs benefited functional biodiversity in intensively farmed landscapes. To this end we established eleven annual flower strips with a seed mixture targeted for both natural enemies and pollinators, on areas were farmers had planned for EFAs. We determined effects on aphids and their natural enemies in cereal fields close to six of the flower strips, and for solitary bees and wasp close to and in the surroundings of all eleven flower strips. We found that annual flower strips benefited the abundance of hoverfly larvae and possibly also that of solitary bees. However, there were neither any significant effects on natural enemies (other than hoverfly larvae), nor any difference in natural pest control as shown by lack of differences in aphid numbers and parazitation rates. Abundances of solitary bees and wasps in the surrounding landscapes were unaffected, although there was a tendency for more solitary bee cells closer to the strips. We suggest that the critical issue leading to the mostly negative results is the lack of permanent structures to sustain populations of arthropods that in turn can benefit from annual flower strips. Hence, future agri-environmental policies need to carefully consider if and how annual agri-environmental measures should be implemented in intensively managed agricultural landscapes, e.g., by combining them with more permanent structures.

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Natural enemies depend on remnant habitat size in agricultural landscapes

Journal of Forestry Research ◽

10.1007/s11676-015-0043-y ◽

2015 ◽

Vol 26 (2) ◽

pp. 469-477 ◽

Cited By ~ 5

Author(s):

Mainara Xavier Jordani ◽

Érica Hasui ◽

Vinícius Xavier da Silva

Keyword(s):

Natural Enemies ◽

Agricultural Landscapes ◽

Habitat Size ◽

Remnant Habitat

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Gefährlich und nützlich zugleich: Strategien zum Management der invasiven Robinie

Schweizerische Zeitschrift fur Forstwesen ◽

10.3188/szf.2018.0077 ◽

2018 ◽

Vol 169 (2) ◽

pp. 77-85 ◽

Cited By ~ 1

Author(s):

Michaela Vítková ◽

Marco Conedera ◽

Jiří Sádlo ◽

Jan Pergl ◽

Petr Pyšek

Keyword(s):

Time Management ◽

Large Scale ◽

Agricultural Landscape ◽

Black Locust ◽

Robinia Pseudoacacia ◽

Management Strategies ◽

Habitat Type ◽

Agricultural Landscapes ◽

Wide Range ◽

Intensively Managed

Dangerous and useful at the same time: management strategies for the invasive black locust The North American black locust (Robinia pseudoacacia) is considered controversial as many other introduced tree species because of its both positive and negative properties. Based on a literature review and own data we analyze the occurrence of black locust in Czechia and Switzerland and present the management approaches in place. In both countries, black locust is on the blacklist of invasive introduced species. It can grow in a wide range of habitats from urban and agricultural landscape to dry grassland and forest. Meanwhile, the species became in many places part of the environment and human culture, so that neither unrestricted cultivation nor large-scale eradication is feasible. We suggest a context-dependent management which respects the different needs and takes into account the local environmental conditions, land-use, habitat type, risk of spread as well as economic, cultural and biodiversity aspects. To this purpose we propose three management strategies: 1) control respectively gradual suppression of black locust in forests where the species is not welcome, 2) its eradication in sensitive ecosystems as dry grasslands or clear and dry forests and 3) its tolerance in intensively managed agricultural landscapes and in urban environment.

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Positive Correlation between Pesticide Consumption and Longevity in Solitary Bees: Are We Overlooking Fitness Trade-Offs?

Insects ◽

10.3390/insects11110819 ◽

2020 ◽

Vol 11 (11) ◽

pp. 819

Author(s):

Verena Strobl ◽

Domenic Camenzind ◽

Angela Minnameyer ◽

Stephanie Walker ◽

Michael Eyer ◽

...

Keyword(s):

Food Consumption ◽

False Negative ◽

Solitary Bees ◽

Negative Effects ◽

Physiological Factors ◽

Positive Correlation ◽

Agricultural Pesticides ◽

Negative Results ◽

Trade Offs ◽

Survival And Reproduction

The ubiquitous use of pesticides is one major driver for the current loss of biodiversity, and the common practice of simultaneously applying multiple agrochemicals may further contribute. Insect toxicology currently has a strong focus on survival to determine the potential hazards of a chemical routinely used in risk evaluations. However, studies revealing no effect on survival or even indicating enhanced survival are likely to be misleading, if potential trade-offs between survival and other physiological factors are overlooked. Here, we used standard laboratory experiments to investigate the sublethal (i.e., food consumption) and lethal (i.e., survival) effects of two common agricultural pesticides (Roundup® and clothianidin) on adult female solitary bees, Osmia bicornis. The data showed no significant effect of the treatment on cumulative survival; however, a significant positive correlation between herbicide and insecticide exposure and age was revealed, i.e., bees exposed to higher dosages lived longer. As no significant differences in daily food consumption were observed across treatment groups, increased food intake can be excluded as a factor leading to the prolonged survival. While this study does not provide data on fitness effects, two previous studies using solitary bees observed significant negative effects of neonicotinoid insecticides on fitness, yet not on survival. Thus, we conjecture that the observed non-significant effects on longevity may result from a trade-off between survival and reproduction. The data suggest that a focus on survival can lead to false-negative results and it appears inevitable to include fitness or at least tokens of fitness at the earliest stage in future risk assessments.

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The potential of different semi-natural habitats to sustain pollinators and natural enemies in European agricultural landscapes

Agriculture Ecosystems & Environment ◽

10.1016/j.agee.2019.04.009 ◽

2019 ◽

Vol 279 ◽

pp. 43-52 ◽

Cited By ~ 8

Author(s):

Agustín M. Bartual ◽

Louis Sutter ◽

Gionata Bocci ◽

Anna-Camilla Moonen ◽

James Cresswell ◽

...

Keyword(s):

Natural Enemies ◽

Agricultural Landscapes ◽

Natural Habitats

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Solitary Bees and Wasps

Bee World ◽

10.1080/0005772x.1976.11097593 ◽

1976 ◽

Vol 57 (2) ◽

pp. 57-63

Author(s):

Christopher Andrewes

Keyword(s):

Solitary Bees ◽

Solitary Bees And Wasps

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Vibration and sound communication in solitary bees and wasps

Physiological Entomology ◽

10.1111/j.1365-3032.1986.tb00416.x ◽

1986 ◽

Vol 11 (3) ◽

pp. 287-296 ◽

Cited By ~ 14

Author(s):

OLE NÆSBYE LARSEN ◽

GEORG GLEFFE ◽

JAN TENGÖ

Keyword(s):

Solitary Bees ◽

Sound Communication ◽

Solitary Bees And Wasps

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Proportion of Grassland at Landscape Scale Drives Natural Pest Control Services in Agricultural Landscapes

Frontiers in Ecology and Evolution ◽

10.3389/fevo.2021.607023 ◽

2021 ◽

Vol 9 ◽

Author(s):

Thomas Perrot ◽

Adrien Rusch ◽

Camille Coux ◽

Sabrina Gaba ◽

Vincent Bretagnolle

Keyword(s):

Pest Control ◽

Crop Yields ◽

Spatial Arrangement ◽

Agricultural Landscapes ◽

Dispersal Ability ◽

Forest Fragments ◽

Natural Habitats ◽

Arable Fields ◽

Cereal Fields ◽

Natural Pest Control

Managing regulating ecosystem services delivered by biodiversity in farmland is a way to maintain crop yields while reducing the use of agrochemicals. Because semi-natural habitats provide shelter and food for pest enemies, a higher proportion of semi-natural habitats in the landscape or their proximity to crops may enhance pest control in arable fields. However, the ways in which the spatial arrangement of these habitats affects the delivery of this beneficial ecosystem service to crops remains poorly known. Here, we investigated the relative effects of the amount of grassland in the landscape versus the distance to the nearest grassland on the predation rates of weed seeds and aphids into 52 cereal fields. We found that both seed and aphid predation levels increased with the proportion of grassland in a 500 m radius buffer while the distance to the nearest grassland displayed no effect. We show that increasing from 0 to 50% the proportion of grasslands in a 500 m radius, respectively, increased seed and aphid predation by 38 and 20%. In addition to the strong effect of the proportion of grassland, we found that seed predation increased with the proportion of forest fragments while aphid predation increased with the proportion of organic farming in the landscape. Overall, our results reveal that natural pest control in cereal crops is not related to the distance to the nearest grassland, suggesting that natural enemies are not limited by their dispersal ability. Our study indicates that maintaining key semi-natural habitats, such as grasslands, is needed to ensure natural pest control and support food production in agricultural landscapes.

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Influence of distance from adjacent forest fragments on aphids (Hemiptera: Aphididae) parasitoidism in wheat fields in Parana State, Brazil

Revista Colombiana de Entomología ◽

10.25100/socolen.v42i1.6661 ◽

2016 ◽

Vol 42 (1) ◽

pp. 1 ◽

Cited By ~ 1

Author(s):

Orcial Ceolin Bortolotto ◽

Ayres De Oliveira Menezes Jr. ◽

Adriano Thibes Hoshino ◽

Hugo Reis Medeiros

Keyword(s):

Density Dependence ◽

Natural Enemies ◽

Neotropical Region ◽

Agricultural Landscapes ◽

Clear Relationship ◽

Forest Fragments ◽

The North ◽

Inverse Density Dependence ◽

Planting Season ◽

Aphid Abundance

In agricultural landscapes, non-crop habitats, such as forest fragments, may not only play an important role for natural enemies, but may also favor some pests. However, there is a lack of studies in Neotropical regions about these interactions. Thus, the aim of this study was to investigate aphid parasitoidism at two distances (25 m and 525 m) from edges of forest fragments adjacent to wheat crops. This research was carried out in four wheat fields in the north of the Parana state, Brazil, during the planting season of 2009. In total, 8,392 aphids were counted, representing two species. There were 589 total aphid-parasitized (“mummies”), represented by six species. In all four areas, aphid abundance and parasitoidism showed no clear relationship to distance from forest fragments (25 m and 525 m). In addition, inverse density dependence between aphids and parasitoidism was observed. In summary, this study does not support the hypothesis of higher parasitoidism of aphids near edges of forest fragments. However, this is the first study in the Neotropical region and more research must be done to better understand this tritrophic interaction.

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