Semi-natural habitats promote winter survival of wild-living honeybees in an agricultural landscape

The invasive Drosophila suzukii feeds and reproduces on various cultivated and wild fruits and moves between agricultural and semi-natural habitats. Hedges in agricultural landscapes play a vital role in the population development of D. suzukii, but also harbor a diverse community of natural enemies. We investigated predation by repeatedly exposing cohorts of D. suzukii pupae between June and October in dry and humid hedges at five different locations in Switzerland. We sampled predator communities and analyzed their gut content for the presence of D. suzukii DNA based on the COI marker. On average, 44% of the exposed pupae were predated. Predation was higher in dry than humid hedges, but did not differ significantly between pupae exposed on the ground or on branches and among sampling periods. Earwigs, spiders, and ants were the dominant predators. Predator communities did not vary significantly between hedge types or sampling periods. DNA of D. suzukii was detected in 3.4% of the earwigs, 1.8% of the spiders, and in one predatory bug (1.6%). While the molecular gut content analysis detected only a small proportion of predators that had fed on D. suzukii, overall predation seemed sufficient to reduce D. suzukii populations, in particular in hedges that provide few host fruit resources.

Download Full-text

Landscape structure affects the sunflower visiting frequency of insect pollinators

Scientific Reports ◽

10.1038/s41598-021-87650-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Károly Lajos ◽

Ferenc Samu ◽

Áron Domonkos Bihaly ◽

Dávid Fülöp ◽

Miklós Sárospataki

Keyword(s):

Landscape Structure ◽

Honey Bees ◽

Agricultural Landscape ◽

Edge Density ◽

Wild Bees ◽

Natural Habitats ◽

Mass Flowering ◽

Positive Effects ◽

Pollinator Community ◽

Foraging Ranges

AbstractMass-flowering crop monocultures, like sunflower, cannot harbour a permanent pollinator community. Their pollination is best secured if both managed honey bees and wild pollinators are present in the agricultural landscape. Semi-natural habitats are known to be the main foraging and nesting areas of wild pollinators, thus benefiting their populations, whereas crops flowering simultaneously may competitively dilute pollinator densities. In our study we asked how landscape structure affects major pollinator groups’ visiting frequency on 36 focal sunflower fields, hypothesising that herbaceous semi-natural (hSNH) and sunflower patches in the landscape neighbourhood will have a scale-dependent effect. We found that an increasing area and/or dispersion of hSNH areas enhanced the visitation of all pollinator groups. These positive effects were scale-dependent and corresponded well with the foraging ranges of the observed bee pollinators. In contrast, an increasing edge density of neighbouring sunflower fields resulted in considerably lower visiting frequencies of wild bees. Our results clearly indicate that the pollination of sunflower is dependent on the composition and configuration of the agricultural landscape. We conclude that an optimization of the pollination can be achieved if sufficient amount of hSNH areas with good dispersion are provided and mass flowering crops do not over-dominate the agricultural landscape.

Download Full-text

Habitats for large branchiopods in the agricultural landscape of the Mureş Floodplain Natural Park: how long will they last?

Crustaceana ◽

10.1163/15685403-bja10131 ◽

2021 ◽

Vol 94 (7) ◽

pp. 775-795

Author(s):

Alfred-Ştefan Cicort-Lucaciu ◽

Gabriel-Lucian Herlo

Keyword(s):

Agricultural Landscape ◽

Habitat Type ◽

Natural Habitats ◽

Natural Landscape ◽

Large Branchiopods ◽

Natural Park ◽

Black Spots ◽

Chirocephalus Diaphanus ◽

Floodplain Area ◽

Large Branchiopod

Abstract In the last two hundred years, the Mureş River Floodplain has suffered major changes caused by dike constructions, meander cutting, and by the transformation of the natural landscape into an agricultural one. In this environmental context, we wanted to find out the degree to which large branchiopod species still survive in the Mureş Floodplain area. Every stagnant aquatic habitat encountered in 2019 in the Mureş Floodplain Natural Park was sampled. For the habitats where more species co-occur, urgent preservation actions must be taken. Most of the species prefer open habitats and have survived in the wheel ruts on agricultural lands. In the absence of natural habitats, the importance of this habitat type becomes a major one. The forest advantages species related to shady habitats, such as Chirocephalus diaphanus. We have found several individuals in the park that showed black spots on their bodies, characteristic of the black disease of fairy shrimp. The presence of the disease only in the populations from wheel ruts suggests that vehicles which make these ruts, could be the carriers of the disease.

Download Full-text

Local changes in communities of wild bees (Hymenoptera: Apoidea, Apiformes): 30 years later

Polish Journal of Entomology ◽

10.2478/pjen-2014-0025 ◽

2014 ◽

Vol 83 (4) ◽

pp. 325-351 ◽

Cited By ~ 4

Author(s):

Józef Banaszak ◽

Halina Ratyńska

Keyword(s):

Agricultural Landscape ◽

Plant Succession ◽

Permanent Plots ◽

Wild Bees ◽

Natural Habitats ◽

Increasing Trend ◽

Quantitative Changes ◽

Abundance And Diversity ◽

Bee Communities ◽

Forest Habitats

ABSTRACT Changes in communities of wild bees (Apiformes) were studied in relation to changes in vegetation in six permanent plots (natural forest habitats in the Wielkopolska National Park, and semi-natural habitats in the agricultural landscape near Turew) at the end of four decades (starting from the late 1970s). In 2008-2010, as many as 100 species of Apiformes were recorded there, which is more than reported in earlier decades. The most stable bee communities were those in forest habitats (oak-hornbeam forest, oak forest). Substantial qualitative and quantitative changes in vegetation and bee communities were recorded only after the renaturalisation of a former xerothermic grassland, which had become overgrown with shrubs and trees as a result of plant succession. Human interference (e.g. the felling of some trees growing along a road, clearance of understorey shrubs, ploughing of roadside margins) at selected refuge habitats in the agricultural landscape led to short-term fluctuations in bee abundance and diversity, but an increasing trend in abundance was noted.

Download Full-text

Semi-natural habitats mediate influence of inter-annual landscape variation on cereal aphid-parasitic wasp system in an agricultural landscape

Biological Control ◽

10.1016/j.biocontrol.2018.09.011 ◽

2019 ◽

Vol 128 ◽

pp. 17-23 ◽

Cited By ~ 3

Author(s):

ZiHua Zhao ◽

Gadi V.P. Reddy

Keyword(s):

Agricultural Landscape ◽

Parasitic Wasp ◽

Cereal Aphid ◽

Natural Habitats ◽

Landscape Variation

Download Full-text

More pests but less treatments: ambivalent effect of landscape complexity on Conservation Biological Control

10.1101/2021.03.19.436155 ◽

2021 ◽

Author(s):

Patrizia Zamberletti ◽

Khadija Sabir ◽

Thomas Opitz ◽

Olivier Bonnefon ◽

Edith Gabriel ◽

...

Keyword(s):

Biological Control ◽

Landscape Structure ◽

Agricultural Landscape ◽

Multiple Scales ◽

Conservation Biological Control ◽

Agricultural Landscapes ◽

Predator Population ◽

Natural Habitats ◽

Landscape Complexity ◽

Spatio Temporal

AbstractIn agricultural landscapes, the amount and organization of crops and semi-natural habitats (SNH) have the potential to promote a bundle of ecosystem services due to their influence on ecological community at multiple spatio-temporal scales. SNH are relatively undisturbed and are often source of complementary resources and refuges, supporting more diverse and abundant natural pest enemies. However, the nexus of SNH proportion and organization with pest suppression is not trivial. It is thus crucial to understand how the behavior of pest and auxiliary species, the underlying landscape structure, and their interaction may influence conservation biological control (CBC). Here, we develop a generative stochastic landscape model to simulate realistic agricultural landscape compositions and configurations of fields and linear elements. Generated landscapes are used as spatial support over which we simulate a spatially explicit predator-prey dynamic model. We find that SNH boost predator population, but predator movement from hedges to fields is fundamental for an efficient pest regulation by auxiliaries and to decrease pesticide treatments. Moreover landscape elements may lead to different effects on pest reduction depending on the considered scale. Integration of species behaviors and traits with landscape structure at multiple scales are needed to provide useful insights for CBC.

Download Full-text

Determining Plant Diversity within Interconnected Natural Habitat Remnants (Ecological Network) in an Agricultural Landscape: A Matter of Sampling Design?

Diversity ◽

10.3390/d14010012 ◽

2021 ◽

Vol 14 (1) ◽

pp. 12

Author(s):

Francesco Liccari ◽

Maurizia Sigura ◽

Enrico Tordoni ◽

Francesco Boscutti ◽

Giovanni Bacaro

Keyword(s):

Plant Communities ◽

Plant Diversity ◽

Sampling Design ◽

Agricultural Landscape ◽

Natural Habitat ◽

Vascular Plant ◽

Habitat Types ◽

Natural Habitats ◽

Pilot Studies ◽

Integrated Method

In intensively used and human-modified landscapes, biodiversity is often confined to remnants of natural habitats. Thus, identifying ecological networks (ENs) necessary to connect these patches and maintain high levels of biodiversity, not only for conservation but also for the effective management of the landscape, is required. However, ENs are often defined without a clear a-priori evaluation of their biodiversity and are seldom even monitored after their establishment. The objective of this study was to determine the adequate number of replicates to effectively characterize biodiversity content of natural habitats within the nodes of an EN in north-eastern Italy, based on vascular plant diversity. Plant communities within habitat types of the EN’s nodes were sampled through a hierarchical sampling design, evaluating both species richness and compositional dissimilarity. We developed an integrated method, consisting of multivariate measures of precision (MultSE), rarefaction curves and diversity partitioning approaches, which was applied to estimate the minimum number of replicates needed to characterize plant communities within the EN, evaluating also how the proposed optimization in sampling size affected the estimations of the characteristics of habitat types and nodes of the EN. We observed that reducing the total sampled replicates by 85.5% resulted to sufficiently characterize plant diversity of the whole EN, and by 72.5% to exhaustively distinguish plant communities among habitat types. This integrated method helped to fill the gap regarding the data collection to monitor biodiversity content within existing ENs, considering temporal and economic resources. We therefore suggest the use of this quantitative approach, based on probabilistic sampling, to conduct pilot studies in the context of ENs design and monitoring, and in general for habitat monitoring.

Download Full-text

Ecological Stoichiometry of Bumblebee Castes, Sexes, and Age Groups

Frontiers in Physiology ◽

10.3389/fphys.2021.696689 ◽

2021 ◽

Vol 12 ◽

Author(s):

Ronalds Krams ◽

Māris Munkevics ◽

Sergejs Popovs ◽

Linda Dobkeviča ◽

Jonathan Willow ◽

...

Keyword(s):

Ecological Stoichiometry ◽

Agricultural Landscape ◽

Chemical Elements ◽

Bombus Terrestris ◽

Nitrogen Concentration ◽

Elemental Content ◽

Low Carbon ◽

Natural Habitats ◽

Carbon To Nitrogen Ratio ◽

Nitrogen Ratio

Ecological stoichiometry is important for revealing how the composition of chemical elements of organisms is influenced by their physiological functions and ecology. In this study, we investigated the elemental body composition of queens, workers, and males of the bumblebee Bombus terrestris, an important pollinator throughout Eurasia, North America, and northern Africa. Our results showed that body elemental content differs among B. terrestris castes. Young queens and workers had higher body nitrogen concentration than ovipositing queens and males, while castes did not differ significantly in their body carbon concentration. Furthermore, the carbon-to-nitrogen ratio was higher in ovipositing queens and males. We suggest that high body nitrogen concentration and low carbon-to-nitrogen ratio in young queens and workers may be related to their greater amount of flight muscles and flight activities than to their lower stress levels. To disentangle possible effects of stress in the agricultural landscape, further studies are needed to compare the elemental content of bumblebee bodies between natural habitats and areas of high-intensity agriculture.

Download Full-text

Diet composition, body condition and sexual size dimorphism of the common African toad (Amietophrynus regularis) in urban and agricultural landscape

10.1101/2021.01.25.428067 ◽

2021 ◽

Author(s):

Benjamin Yeboah Ofori ◽

John Bosu Mensah ◽

Roger Sigismund Anderson ◽

Daniel Korley Attuquayefio

Keyword(s):

Body Condition ◽

Diet Composition ◽

Sexual Size Dimorphism ◽

Agricultural Landscape ◽

Individual Characteristics ◽

Generalist Predator ◽

Natural Habitats ◽

Size Dimorphism ◽

The Common ◽

Prey Items

AbstractLand use and land cover change (LULCC) are major drivers of global biodiversity loss. The conversion of natural habitats into human-modified landscapes poses novel and multifaceted environmental stressors to organisms, influencing their ecology, physiology, life history and fitness. Although the effects of LULCC have been studied extensively at the community level, there is scant information about its effect on population and individual characteristics. We assessed the diet composition, body condition, and sexual size dimorphism of the common African toad (Amietophrynus regularis) in urban and agricultural landscape. Diet composition was evaluated using gut content analysis, while body condition was measured using residual mass index. Overall, 935 prey items comprising six classes, at least 18 orders and 31 families were obtained from toads. This broad dietary niche suggested that Amietophrynus regularis is a generalist predator. The family Formicidae was the most consumed prey item, with a frequency of occurrence above 80% at both sites. We found no sex- or habitat-biased dietary partitioning in the toads. A statistically significant positive correlation existed between snout-vent-length (SVL) and diversity of prey items (Pearson’s correlation r = 0.999, p ≤ 0.0001) for toads from farmland, which also had better body conditions. The toads showed female-biased sexual size dimorphism, but males had longer tibio-fibula, radio-ulna, foot, and distal fore limbs. This study is probably the first to assess the diet composition, body condition and sexual size dimorphism of Amietophrynus regularis simultaneously. The ecological, evolutionary and conservation implications of our findings are discussed.

Download Full-text

The loss of woody linear landscape elements in agriculture landscape in Wielkopolska region (Poland) in 21th century

BALTIC FORESTRY ◽

10.46490/bf459 ◽

2021 ◽

Vol 27 (1) ◽

Author(s):

Krzysztof Kujawa ◽

Krzysztof Janku ◽

Mostefa Mana ◽

Adam Choryński

Keyword(s):

Western Europe ◽

Agricultural Landscape ◽

Rapid Development ◽

High Rate ◽

Natural Habitats ◽

Landscape Elements ◽

Linear Landscape Elements ◽

Linear Elements ◽

Water Courses ◽

Agriculture Management

With the loss of natural and semi-natural habitats, the diversity and the amount of ecosystem services that can be provided in the agricultural landscape are diminishing, and self-regulatory abilities decrease. The aim of the research (72 sample plots – 1 x 1 km squares, mean time span equal to 8 years) was to recognise the changes in the number and length of woody (tree or shrub) linear landscape elements, and the number of solitary trees in the Wielkopolska region to verify how rapid development of agriculture in Poland in the 21st century affects the landscape structure. The analyses show a decline by 9.3% (from 2.17 to 1.97 km/km2) in length of woody linear elements, 7.4% (from 16.5 to 15.0 per km2) in number of woody linear elements, and 14.6% (from 28.8 to 24.4 per km2) in solitary trees. The loss was significantly faster in the period (2017-2018) of liberalisation of the regulations on tree and shrub removal, mainly due to a high rate of removal in plots located in an urbanized landscape. The decrease in length of woody linear elements occurred in all the categories of their location distinguished in the study (by 9-41% in a category). The highest loss occurred in the woody linear elements located along melioration ditches and water courses, along roads, and in the outskirt of towns. These changes are similar to those occurring in the 20th century in western Europe. The decrease in the number of woody linear landscape elements and solitary trees can be considered an indicator of the unsustainable agriculture management.

Download Full-text