Predation on Drosophila suzukii within Hedges in the 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.

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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.

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More pests but less pesticide applications: Ambivalent effect of landscape complexity on conservation biological control

PLoS Computational Biology ◽

10.1371/journal.pcbi.1009559 ◽

2021 ◽

Vol 17 (11) ◽

pp. e1009559

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 ◽

Dispersal Ability ◽

Natural Habitats ◽

Linear Elements ◽

Pest Density

In 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, therefore 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 natural enemy 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 increased SNH presence boosts predator populations by sustaining high predator density that regulates and keeps pest density below the pesticide application threshold. However, predator presence over all the landscape helps to stabilize the pest population by keeping it under this threshold, which tends to increase pest density at the landscape scale. In addition, the joint effect of SNH presence and predator dispersal ability among hedge and field interface results in a stronger pest regulation, which also limits pest growth. Considering properties of both fields and linear elements, such as local structure and geometric features, provides deeper insights for pest regulation; for example, hedge presence at crop field boundaries clearly strengthens CBC. Our results highlight that the integration of species behaviors and traits with landscape structure at multiple scales is necessary to provide useful insights for CBC.

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Hedgerows Have a Barrier Effect and Channel Pollinator Movement in the Agricultural Landscape

Journal of Landscape Ecology ◽

10.1515/jlecol-2015-0001 ◽

2015 ◽

Vol 8 (1) ◽

pp. 22-31 ◽

Cited By ~ 9

Author(s):

Felix Klaus ◽

Julia Bass ◽

Lisa Marholt ◽

Birte Müller ◽

Björn Klatt ◽

...

Keyword(s):

Agricultural Landscape ◽

Pollen Dispersal ◽

Agricultural Landscapes ◽

Fluorescent Dye ◽

Natural Habitats ◽

Pollination Services ◽

Landscape Elements ◽

Mobile Species ◽

Management Plans ◽

Linear Landscape Elements

Abstract Agricultural intensification and the subsequent fragmentation of semi-natural habitats severely restrict pollinator and pollen movement threatening both pollinator and plant species. Linear landscape elements such as hedgerows are planted for agricultural and conservation purposes to increase the resource availability and habitat connectivity supporting populations of beneficial organisms such as pollinators. However, hedgerows may have unexpected effects on plant and pollinator persistence by not just channeling pollinators and pollen along, but also restricting movement across the strip of habitat. Here, we tested how hedgerows influence pollinator movement and pollen flow. We used fluorescent dye particles as pollen analogues to track pollinator movement between potted cornflowers Centaurea cyanus along and across a hedgerow separating two meadows. The deposition of fluorescent dye was significantly higher along the hedgerow than across the hedgerow and into the meadow, despite comparable pollinator abundances. The differences in pollen transfer suggest that hedgerows can affect pollinator and pollen dispersal by channeling their movement and acting as a permeable barrier. We conclude that hedgerows in agricultural landscapes can increase the connectivity between otherwise isolated plant and pollinator populations (corridor function), but can have additional, and so far unknown barrier effects on pollination services. Functioning as a barrier, linear landscape elements can impede pollinator movement and dispersal, even for highly mobile species such as bees. These results should be considered in future management plans aiming to enhance the persistence of threatened pollinator and plant populations by restoring functional connectivity and to ensure sufficient crop pollination in the agricultural landscape.

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Short Communication: Landscape composition alters parasitoid wasps but not their host diversity in tropical agricultural landscapes

Biodiversitas Journal of Biological Diversity ◽

10.13057/biodiv/d210452 ◽

2020 ◽

Vol 21 (4) ◽

Author(s):

Tazkiyatul Syahidah ◽

AKHMAD RIZALI ◽

LILIK B. PRASETYO ◽

PUDJIANTO ◽

DAMAYANTI BUCHORI

Keyword(s):

Agricultural Landscape ◽

Short Communication ◽

Parasitoid Wasp ◽

Landscape Composition ◽

Agricultural Landscapes ◽

Parasitoid Wasps ◽

Natural Habitats ◽

Host Diversity ◽

Crop Fields ◽

Lepidopteran Larvae

Abstract. Syahidah T, Rizali A, Prasetyo LB, Pudjianto, Buchori D. 2020. Short Communication: Landscape composition alters parasitoid wasps but not their host diversity in tropical agricultural landscapes. Biodiversitas 21: 1702-1706. The diversity of parasitoid wasps and their hosts in an agricultural landscape is affected by crop management and habitat conditions around crop fields. The composition of agricultural landscapes that are dominated by non-crop or natural habitats are assumed to be able to support the presence of parasitoid wasps as biological control of pests. The aim of this study was to investigate the effect of landscape composition on the diversity of parasitoid wasps and their hosts in agricultural landscapes. The research observations were conducted on six fields of long-bean cultivation located in Bogor District, West Java Province, Indonesia. Parasitoid wasps were collected by hand-collecting of their hosts (lepidopteran larvae) within 60 m distance transect to each long-bean field. In total, 17 species of parasitoid wasps and 12 species of lepidopteran larvae were found from all agricultural landscapes. A parasitoid wasp, Microplitis manilae was found in all long-bean fields (except Bantarjaya) and only parasitized the tobacco cutworm (Spodoptera litura). The tomato looper, Chrysodeixis chalcites had the highest associated parasitoids and was also parasitized by Braconidae sp5 which was also a parasitoid of S. litura. Based on the analysis results, the patch numbers of natural habitats had a positive effect on the diversity of parasitoid wasps and had no effect on the diversity of lepidopteran larvae. In conclusion, landscape compositions with patchy natural habitats have an important role to preserve beneficial insects and maintain ecosystem services in tropical agricultural landscapes.

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Conserving predators across agricultural landscapes in Colombia: habitat use and space partitioning by jaguars, pumas, ocelots and jaguarundis

Oryx ◽

10.1017/s0030605318000327 ◽

2018 ◽

Vol 54 (4) ◽

pp. 554-563 ◽

Cited By ~ 5

Author(s):

Valeria Boron ◽

Panteleimon Xofis ◽

Andres Link ◽

Esteban Payan ◽

Joseph Tzanopoulos

Keyword(s):

Land Use ◽

Habitat Use ◽

Oil Palm ◽

Agricultural Landscape ◽

Agricultural Landscapes ◽

Conservation Strategies ◽

Space Partitioning ◽

Natural Habitats ◽

Positive Effect ◽

Felid Species

AbstractLoss and degradation of natural habitats continue to increase across the tropics as a result of agricultural expansion. Consequently, there is an urgent need to understand their effects, and the distribution and habitat requirements of wildlife within human-modified landscapes, to support the conservation of threatened species, such as felids. We combined camera trapping and land cover data into occupancy models to study the habitat use and space partitioning by four sympatric felid species in an agricultural landscape in Colombia. Land use in the area includes cattle ranching and oil palm cultivation, the latter being an emerging land use type in the Neotropics. Factors determining species occupancy were the presence of wetlands for jaguars (positive effect); water proximity for pumas (positive effect); and presence of pastures for ocelots and jaguarundis (negative effect). Only ocelots were occasionally recorded in oil palm areas. Our results suggest that to align development with the conservation of top predators it is crucial to maintain areas of forest and wetland across agricultural landscapes and to restrict agricultural and oil palm expansion to modified areas such as pastures, which are of limited conservation value. Because there is no spatial segregation between the felid species we studied, conservation strategies that benefit all of them are possible even in modified landscapes.

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The Relict Ecosystem of Maytenus senegalensis subsp. europaea in an Agricultural Landscape: Past, Present and Future Scenarios

Land ◽

10.3390/land10010001 ◽

2020 ◽

Vol 10 (1) ◽

pp. 1

Author(s):

Antonio J. Mendoza-Fernández ◽

Fabián Martínez-Hernández ◽

Esteban Salmerón-Sánchez ◽

Francisco J. Pérez-García ◽

Blas Teruel ◽

...

Keyword(s):

Plant Communities ◽

Ecological Niche ◽

Agricultural Landscape ◽

Agricultural Landscapes ◽

Eastern Coast ◽

Ecological Value ◽

Distribution Models ◽

European Continent ◽

Major Interest ◽

Maytenus Senegalensis

Maytenus senegalensis subsp. europaea is a shrub belonging to the Celastraceae family, whose only European populations are distributed discontinuously along the south-eastern coast of the Iberian Peninsula, forming plant communities with great ecological value, unique in Europe. As it is an endangered species that makes up plant communities with great palaeoecological significance, the development of species distribution models is of major interest under different climatic scenarios, past, present and future, based on the fact that the climate could play a relevant role in the distribution of this species, as well as in the conformation of the communities in which it is integrated. Palaeoecological models were generated for the Maximum Interglacial, Last Maximum Glacial and Middle Holocene periods. The results obtained showed that the widest distribution of this species, and the maximum suitability of its habitat, occurred during the Last Glacial Maximum, when the temperatures of the peninsular southeast were not as contrasting as those of the rest of the European continent and were favored by higher rainfall. Under these conditions, large territories could act as shelters during the glacial period, a hypothesis reflected in the model’s results for this period, which exhibit a further expansion of M. europaea’s ecological niche. The future projection of models in around 2070, for four Representative Concentration Pathways according to the fifth report of the Intergovernmental Panel on Climate Change, showed that the most favorable areas for this species would be Campo de Dalías (southern portion of Almería province) as it presents the bioclimatic characteristics of greater adjustment to M. europaea’s ecological niche model. Currently, some of the largest specimens of the species survive in the agricultural landscapes in the southern Spain. These areas are almost totally destroyed and heavily altered by intensive agriculture greenhouses, also causing a severe fragmentation of the habitat, which implies a prospective extinction scenario in the near future.

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Family graveyards form underappreciated local plant diversity hotspots in China's agricultural landscapes

Scientific Reports ◽

10.1038/s41598-020-80362-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Cheng Gong ◽

Liangtao Li ◽

Jan C. Axmarcher ◽

Zhenrong Yu ◽

Yunhui Liu

Keyword(s):

Species Richness ◽

Plant Species ◽

Natural Habitat ◽

Plant Species Richness ◽

Agricultural Landscapes ◽

Natural Habitats ◽

Landscape Features ◽

Habitat Islands ◽

Local Plant ◽

Ecological Functioning

AbstractIn the intensively farmed, homogenous agricultural landscape of the North China Plain, family graveyards form distinct cultural landscape features. In addition to their cultural value, these graveyards represent semi-natural habitat islands whose potential roles in biodiversity conservation and ecological functioning has remained poorly understood. In this study, we investigated plant species richness on 199 family graveyards of different ages and sizes. In accordance with biogeography theory, both overall and insect-pollinated plant species richness increased with area and age of graveyards. Even small graveyards show a strong potential for conserving local plant richness, and a mosaic of both large and small family graveyards could play an important role in the conservation of farmland biodiversity and related ecosystem functions. The launch of agri-environmental measures that conserve and create semi-natural habitats, in turn benefitting agricultural biodiversity and ecological functioning, has proven difficult in China due to the shortage of dispensable arable land. Given the great value of family graveyards as semi-natural habitats reflected in our study, we propose to focus preliminary efforts on conserving these landscape features as existing, widespread and culturally important semi-natural habitat islands. This would represent an effective, complementary policy to a subsequent re-establishment of other semi-natural habitats for the conservation of biodiversity and ecological functioning in agricultural landscapes.

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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.

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Determinants of bird assemblage composition in riparian vegetation on sugarcane farms in the Queensland Wet Tropics

Pacific Conservation Biology ◽

10.1071/pc14904 ◽

2015 ◽

Vol 21 (1) ◽

pp. 60 ◽

Cited By ~ 4

Author(s):

Anita F. Keir ◽

Richard G. Pearson ◽

Robert A. Congdon

Keyword(s):

Riparian Vegetation ◽

Wildlife Conservation ◽

Agricultural Landscape ◽

Riparian Zone ◽

Riparian Forest ◽

Agricultural Landscapes ◽

Generalist Species ◽

Assemblage Composition ◽

Bird Assemblages ◽

Wet Tropics

Remnant habitat patches in agricultural landscapes can contribute substantially to wildlife conservation. Understanding the main habitat variables that influence wildlife is important if these remnants are to be appropriately managed. We investigated relationships between the bird assemblages and characteristics of remnant riparian forest at 27 sites among sugarcane fields in the Queensland Wet Tropics bioregion. Sites within the remnant riparian zone had distinctly different bird assemblages from those of the forest, but provided habitat for many forest and generalist species. Width of the riparian vegetation and distance from source forest were the most important factors in explaining the bird assemblages in these remnant ribbons of vegetation. Gradual changes in assemblage composition occurred with increasing distance from source forest, with species of rainforest and dense vegetation being replaced by species of more open habitats, although increasing distance was confounded by decreasing riparian width. Species richness increased with width of the riparian zone, with high richness at the wide sites due to a mixture of open-habitat species typical of narrower sites and rainforest species typical of sites within intact forest, as a result of the greater similarity in vegetation characteristics between wide sites and the forest proper. The results demonstrate the habitat value for birds of remnant riparian vegetation in an agricultural landscape, supporting edge and open vegetation species with even narrow widths, but requiring substantial width (>90 m) to support specialists of the closed forest, the dominant original vegetation of the area.

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