Landscape-scale forest cover increases the abundance of Drosophila suzukii and parasitoid wasps

2018 ◽  
Vol 31 ◽  
pp. 33-43 ◽  
Author(s):  
Eduardo Haro-Barchin ◽  
Jeroen Scheper ◽  
Cristina Ganuza ◽  
G. Arjen De Groot ◽  
Fernanda Colombari ◽  
...  
Keyword(s):  
Forest Cover ◽  
Landscape Scale ◽  
Parasitoid Wasps ◽  
Drosophila Suzukii

scholarly journals Seed Removal Rates in Forest Remnants Respond to Forest Loss at the Landscape Scale

Forests ◽  
2020 ◽  
Vol 11 (11) ◽  
pp. 1144
Author(s):  
Alain Hambuckers ◽  
Franck Trolliet ◽  
Astrid Simon ◽  
Eliana Cazetta ◽  
Larissa Rocha-Santos
Keyword(s):  
Forest Cover ◽  
Removal Rate ◽  
Supply And Demand ◽  
Landscape Scale ◽  
Fast Method ◽  
Seed Removal ◽  
Removal Rates ◽  
Forest Remnants ◽  
Forested Landscapes ◽  
Plant Animal Interactions

Seed removal is a key component of seed dispersal and may be influenced by both landscape-scale and local attributes, and it has been used as an indicator of the intensity of interactions between ecosystem components. We examined how the seed removal rates, which integrate the activity of seed dispersers and seed predators, vary with landscape-scale forest cover. We collected data under 34 trees belonging to two zoochoric species (Helicostylis tomentosa (Poepp. and Endl.) J. F. Macbr. and Inga vera Willd.) in 17 remnants in the Brazilian Atlantic forest, with different percentages of forest cover. The seed removal rate was estimated using a fast method based on the abundance of intact fruits and fruit scraps on the ground. The amount of forest cover affected the rate of seed removal in a humpbacked shape, with a maximum seed removal rate at intermediate forest cover. Seed removal rates must be related to the amount of food resources offered and diversity of dispersers and predators in the region. In landscapes with intermediate forest amount, there is a better balance between supply and demand for fruits, leading to a higher seed removal rate than more deforested or forested landscape. Our results also show that local factors, such as crop size and canopy surface, together with forest cover amount, are also important to the removal rate, depending on the species. In addition, our results showed that plant–animal interactions are occurring in all fragments, but the health status of these forests is similar to disturbed forests, even in sites immersed in forested landscapes.

scholarly journals Modeling Aquatic Macroinvertebrate Richness Using Landscape Attributes

2015 ◽  
Vol 2015 ◽  
pp. 1-14 ◽  
Author(s):  
Marcia S. Meixler ◽  
Mark B. Bain
Keyword(s):  
Water Quality ◽  
Forest Cover ◽  
Riparian Forest ◽  
Landscape Scale ◽  
Riparian Zones ◽  
Feeding Guilds ◽  
Biological Databases ◽  
Aquatic Macroinvertebrate ◽  
Life Habits ◽  
Landscape Attributes

We used a rapid, repeatable, and inexpensive geographic information system (GIS) approach to predict aquatic macroinvertebrate family richness using the landscape attributes stream gradient, riparian forest cover, and water quality. Stream segments in the Allegheny River basin were classified into eight habitat classes using these three landscape attributes. Biological databases linking macroinvertebrate families with habitat classes were developed using life habits, feeding guilds, and water quality preferences and tolerances for each family. The biological databases provided a link between fauna and habitat enabling estimation of family composition in each habitat class and hence richness predictions for each stream segment. No difference was detected between field collected and modeled predictions of macroinvertebrate families in a pairedt-test. Further, predicted stream gradient, riparian forest cover, and total phosphorus, total nitrogen, and suspended sediment classifications matched observed classifications much more often than by chance alone. High gradient streams with forested riparian zones and good water quality were predicted to have the greatest macroinvertebrate family richness and changes in water quality were predicted to have the greatest impact on richness. Our findings indicate that our model can provide meaningful landscape scale macroinvertebrate family richness predictions from widely available data for use in focusing conservation planning efforts.

scholarly journals Throughfall in balsam fir: Some landscape-scale implications in western Newfoundland

2007 ◽  
Vol 83 (2) ◽  
pp. 180-186
Author(s):  
A. R. van Kesteren
Keyword(s):  
Forest Cover ◽  
Hydrological Cycle ◽  
Abies Balsamea ◽  
Landscape Scale ◽  
Tree Canopy ◽  
Balsam Fir ◽  
Slope Aspect ◽  
Watershed Scale ◽  
Landscape Studies

Throughfall, the process of rainfall passage through a tree canopy to the forest floor, is a critical hydrological cycle component affecting in situ soil to watershed-scale processes. The process has been widely studied at plot scales, but integrative forest stand and landscape studies are rare. A landscape-scale study was undertaken to investigate balsam fir (Abies balsamea (L.) Mill.) forest cover, slope aspect, and interaction of these factors on throughfall receipt in western Newfoundland. ANOVA analyses found balsam fir forest cover to be the predominant variable influencing throughfall over the summer-to-autumn season. Slope aspect and interactions of forest cover and aspect were not significant. Some landscape-scale implications are discussed. Key words: balsam fir, forest hydrology, landscape scale, slope aspect, throughfall

scholarly journals Looking beyond forest cover: An analysis of landscape-scale predictors of forest degradation in the Brazilian Amazon

2021 ◽  
Author(s):  
Clement Bourgoin ◽  
Julie Betbeder ◽  
Renan Le Roux ◽  
Valery Gond ◽  
Johan Oszwald ◽  
...  
Keyword(s):  
Forest Cover ◽  
Brazilian Amazon ◽  
Forest Degradation ◽  
Landscape Scale

scholarly journals The preference of Trichopria drosophilae for pupae of Drosophila suzukii is independent of host size

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Benedikt J. M. Häussling ◽  
Judith Lienenlüke ◽  
Johannes Stökl
Keyword(s):  
Host Preference ◽  
Biocontrol Agent ◽  
Parasitoid Wasps ◽  
Drosophila Suzukii ◽  
Significant Preference ◽  
Video Recordings ◽  
Promising Agent ◽  
Pupal Size ◽  
Host Pupa ◽  
Set Up

AbstractControlling the cosmopolitan pest Drosophila suzukii (spotted wing drosophila) is a challenge for fruit growers. A promising agent for biological control of that pest are parasitoid wasps. Especially the widespread pupal parasitoid Trichopria drosophilae had shown the ability to parasitise the pest fly. However, as a biocontrol agent, parasitoids can only be effective when they prefer the pest to other insects. Until now studies have been inconsistent concerning the preference of T. drosophilae for D. suzukii and whether the preference depends on pupal volume. To clarify this inconsistency, we used video recordings of parasitisation experiments with a set up to observe the direct host preference of the parasitoid. Additionally, the volume of each host pupa was measured. We found significant preference of T. drosophilae for D. suzukii pupae independent of the pupal size and of the host species the wasps were reared on. The article also discusses the sex ratio and the success of the parasitoid in the different pupae characteristics.

scholarly journals Matrix quality determines the strength of habitat loss filtering on bird communities at the landscape scale

2021 ◽  
Author(s):  
Melina de Souza Leite ◽  
Andrea Larissa Boesing ◽  
Jean Paul Metzger ◽  
Paulo Inácio Prado
Keyword(s):  
Habitat Loss ◽  
Community Assembly ◽  
Forest Cover ◽  
Landscape Scale ◽  
Native Forest ◽  
Strong Impact ◽  
High Quality ◽  
Matrix Quality ◽  
The Matrix ◽  
Ecological Drift

Habitat loss and fragmentation represent a major threat to biodiversity, however, the modulation of its effects by the non-habitat matrix surrounding habitat patches is still undervalued. The landscape matrix might change community assembly in different ways. For example, low-quality matrices can accentuate environmental filtering by reducing resource availability and/or deteriorating abiotic conditions but they may also over limit dispersal of organisms and make communities more prone to ecological drift. To understand how matrix quality modulates the effects of habitat loss, we quantified the relative importance of environmental filter and ecological drift in bird occurrences across both local and landscape gradients of habitat loss embedded in low- and high-quality matrices. We used a trait-based approach to understand habitat loss filtering effects on birds. We found that low-quality matrices, composed mainly of low-productive pasturelands, increased the severity of habitat loss filtering effects for forest specialist birds, but only at the landscape scale. Bird occurrence was in general higher in high-quality matrices, i.e., more heterogeneous and with low-contrasting edges, indicating the role of the matrix quality on attenuating species extinction risks at the landscape scale probably due to mass effect. Moreover, forest specialists presented a strong negative response to habitat loss filtering across different functional traits, while generalists presented a high variability in traits response to habitat loss. We raised evidence in supporting that landscape habitat loss filtering may be relaxed or reinforced depending on the quality of the matrix, evidencing that matrix quality has a strong impact in modulating community assembly processes in fragmented landscapes. In practical terms, it means that improving matrix quality may help in maintaining the high diversity of birds even without any increase in native forest cover.

scholarly journals Functional decay in tree community within tropical fragmented landscapes: Effects of landscape-scale forest cover

PLoS ONE ◽  
2017 ◽  
Vol 12 (4) ◽  
pp. e0175545 ◽  
Author(s):  
Larissa Rocha-Santos ◽  
Maíra Benchimol ◽  
Margaret M. Mayfield ◽  
Deborah Faria ◽  
Michaele S. Pessoa ◽  
...  
Keyword(s):  
Forest Cover ◽  
Landscape Scale ◽  
Fragmented Landscapes ◽  
Tree Community

Landscape forest loss changes sunfleck dynamics in forest fragments of southern Bahia, Brazil

2021 ◽  
pp. 1-8
Author(s):  
Igor Pires Reis ◽  
Larissa Rocha-Santos ◽  
Adrielle Leal ◽  
Deborah Faria ◽  
Marcelo Schramm Mielke
Keyword(s):  
Forest Canopy ◽  
Tree Mortality ◽  
Forest Cover ◽  
Floristic Composition ◽  
Landscape Scale ◽  
Canopy Gaps ◽  
Forest Fragments ◽  
Forest Fragment ◽  
Southern Bahia ◽  
Forest Understorey

Abstract Landscape-scale habitat loss can change the floristic composition of forest fragments, affecting the survival of specific groups of plants, as shade-tolerant and emergent trees. This increasing in tree mortality creates forest canopy gaps of different sizes that ultimately determine the solar radiation available in the forest understorey. We conducted a study aiming to assess how the loss of forest cover at landscape level (i.e. deforestation) affects the sunfleck dynamics, a proxy of light regime in forest understorey. We expected that fragments located in landscapes with less forest cover have a high number of larger canopy gaps and, consequently, long-lasting sunflecks. In each forest fragment, a 100 per 50 m plot was established, and in each plot, we took 10 hemispherical photographs. The images were analysed using the Gap Light Analyzer software. The sunflecks were divided into six temporal classes. We evidenced that landscape-scale deforestation increased the frequency of all sunfleck intervals >8 min, particularly the long-lasting (> 32 min) sunflecks. We propose that the increasing frequency of long-lasting sunflecks reduces suitability of microhabitat to some shade-tolerant species in local fragments, a potential proximal mechanism contributing to compositional shifts of tree assemblages observed in forest fragments within deforested landscapes.

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