The Interplay Between Thematic Resolution, Forest Cover, and Heterogeneity for Explaining Euglossini Bees Community in an Agricultural Landscape

Human activities have modified the landscape composition. The changes in the landscape structure can be evaluated by metrics, which are influenced, among other factors, by the number of cover classes used for the landscape classification (thematic resolution). In high thematic resolutions, landscape covers that can influence biological responses are identified and detailed. In low thematic resolutions, this detail level is lower because it aggregates different landscape covers in a few classes. However, how the thematic resolution influences our ability to understand landscape structure on biodiversity is poorly explored, particularly for pollinators. Here we asked how thematic resolution affects the explanatory power of landscape composition on explaining Euglossini bees (richness and abundance) within 15 landscapes composed mainly of coffee and pasture. To address this issue, we quantified the association between five attributes of the euglossine bee community and landscape composition: landscape cover classes (%) and landscape heterogeneity. Moreover, we also evaluated how the thematic resolution influences bee responses to landscape structure. We found a strong and positive influence of landscape heterogeneity in low thematic resolutions (i.e., few cover classes on maps) over the richness and rare species abundance. We also observed that- in addition to the forest cover in the landscape- the pasture cover (%) quantified in high thematic resolution positively influenced the total abundance and abundance of common and intermediate species. Our study highlights the importance of maintaining compositional heterogeneity for the orchid bee community in agroecosystems, and forest cover for the biological requirements and conservation of these pollinators. Moreover, the use of different thematic resolutions showed how specific types of landscape covers influence the euglossine community attributes. This can highlight the species preferences for habitats and landscape covers. Thus, we call the attention of landscape ecologists to the importance of the definition of thematic resolution, as our ability to quantify the association between biological responses and landscape structure may be influenced by the number of classes used when building thematic maps.

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Environmental determinants of haemosporidian parasite prevalence in a declining population of Tree swallows

Parasitology ◽

10.1017/s0031182017002128 ◽

2017 ◽

Vol 145 (7) ◽

pp. 961-970 ◽

Cited By ~ 7

Author(s):

Audrey Turcotte ◽

Marc Bélisle ◽

Fanie Pelletier ◽

Dany Garant

Keyword(s):

Forest Cover ◽

Agricultural Landscape ◽

Parasite Prevalence ◽

Landscape Composition ◽

Breeding Period ◽

Tree Swallows ◽

Environmental Determinants ◽

Negative Effects ◽

Haemosporidian Parasite ◽

Haemosporidian Parasites

AbstractThe prevalence of vector-borne parasites such as haemosporidian species is influenced by several environmental factors. While the negative effects of parasitism on hosts are well documented, these can also be amplified by interactions with environmental stressors, many of which are anthropogenic. Yet, we know little about the possible effects of anthropogenic perturbations on parasite prevalence. The goals of this study were to assess the prevalence and environmental determinants of haemosporidian parasites in a declining population of Tree swallows (Tachycineta bicolor) living in an agricultural landscape in southern Québec, Canada. Overall, a low prevalence and a moderate lineage diversity were identified in both adults and nestlings, confirming that transmission can occur during the breeding period. Anthropic areas, extensive cultures (hayfields and pastures) and forest cover within 500 km of nest boxes, as well as daily temperature fluctuations, were all related to infection by haemosporidian parasites. These findings suggest that anthropogenic alterations of landscape composition can modulate the prevalence of haemosporidian parasites in Tree swallows. Our results represent a baseline for future comparative studies assessing haemosporidian parasite prevalence in human-modified landscapes.

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Exploring the Effects of Landscape Structure at Multiple Scales on River Water Characteristics in the Khorramabad and Chalus River basins

10.21203/rs.3.rs-982134/v1 ◽

2021 ◽

Author(s):

Fatemeh Sadeghi Gorbandi ◽

Hamid Torangzar ◽

Ramin Zare ◽

Javad Varvani ◽

Abbas Ahmadi

Keyword(s):

Water Quality ◽

Landscape Structure ◽

Human Activities ◽

Urban Areas ◽

Forest Cover ◽

Multiple Scales ◽

Landscape Composition ◽

Riparian Buffer ◽

Landscape Characteristics ◽

Landscape Composition And Configuration

Abstract Background It is acknowledged that the landscape composition and configuration of land cover within a watershed could influence a watershed environmental and ecological quality. Therefore, rivers receive pollution from their surrounding landscape and the amount and intensity of this pollution are affected by the landscape structure around the river or within a watershed. Methods In this research, we estimated the relationship between landscape characteristics and water quality in two different basins. We used multiple stepwise regression analysis and redundancy analysis to explore the quantitative association between landscape metrics, at both the watershed and riparian buffer scales. Results The riparian buffer scales metrics were more effective in predicting water quality in comparison with the indices at the watershed scale. The landscape composition and configuration explained 80% of the variation in water quality at 100 m buffer, and the value decreased to 79% at 1000 m. At the 100 m buffer scale, ED of the forest, PLADJ, and MESH of urban areas in Khorramabad basin and AI of the forest, ED of urban, and SPLIT of agricultural lands were recognized as significant variables affecting the water quality in the Chalus basin. In other scales only metrics related to agriculture and urban were seen as dominant variables, indicating that these land-use classes are final determinatives in water quality changes in our study areas. Conclusion All dominant variables at each scale indicated a decreasing trend of the landscape impact on the water quality. Although in the Chalus basin human activities were insignificant, they had considerable effects on Chalus river quality, and urban and agriculture were recognized as dominant usages at all scales, implying that a large amount of forest cover cannot impede the effects of human activities in a basin.

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Influence of landscape structure on Euglossini composition in open vegetation environments

Biota Neotropica ◽

10.1590/1676-0611-bn-2016-0294 ◽

2017 ◽

Vol 17 (1) ◽

Cited By ~ 6

Author(s):

Eduardo Freitas Moreira ◽

Rafaela Lorena da Silva Santos ◽

Maxwell Souza Silveira ◽

Danilo Boscolo ◽

Edinaldo Luz das Neves ◽

...

Keyword(s):

Species Richness ◽

Landscape Structure ◽

Multiple Scales ◽

Landscape Heterogeneity ◽

Species Abundance ◽

Information Criterion ◽

Landscape Configuration ◽

Habitat Amount ◽

Savanna Vegetation ◽

Habitat Amount Hypothesis

Abstract The fauna of Euglossini bees is poorly known in savanna regions, making it difficult to understand how these bees use open vegetation environments. The aim of this study was to evaluate the influence of landscape structure on species abundance and composition of Euglossini bees in naturally heterogeneous savanna landscapes. Nine sites were sampled monthly using six traps with chemical baits. Three aromatic essences (eucalyptol, methyl salicylate and vanillin) were used to attract the Euglossini. Surrounding environmental conditions were measured using three independent variables, calculated in multiple scales: index of local vegetation and two landscape indices (Shannon Diversity and area-weighted shape). We compared the competing hypotheses through model selection based on Second-order Akaike Information Criterion (AICc). The four competing hypothesis were: (1) The local vegetation complexity favors Euglossini bees species richness and/or abundance (local vegetation hypothesis); (2) The proportion of the native vegetation types favors Euglossini bees species richness and/or abundance (habitat amount hypothesis); (3) Higher landscape diversity shall increase species richness of Euglossini bees (landscape heterogeneity hypothesis); (4) More complex landscape configuration shall favor the Euglossini bees richness and/or abundance (landscape heterogeneity hypothesis). We sampled 647 individuals belonging to six species of two distinct genera. Our results support the habitat amount hypothesis since bees’ abundance was strongly related with the proportion of habitat in the surrounding landscape. This may be related to the availability of floral and nesting resources in some types of savanna vegetation.

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Bee responses to landscape composition on coupled and decoupled multiscale approaches

10.21203/rs.3.rs-750143/v1 ◽

2021 ◽

Author(s):

Lazaro Carneiro ◽

Milton Cezar Ribeiro ◽

Willian Moura de Aguiar ◽

Camila de Fátima Priante ◽

Wilson Frantine-Silva ◽

...

Keyword(s):

Forest Cover ◽

Linear Models ◽

Landscape Heterogeneity ◽

Spatial Scales ◽

Landscape Composition ◽

Landscape Context ◽

Multiscale Approach ◽

Ecological Processes ◽

Positive Effects ◽

Scale Of Effect

Abstract ContextMultiscale approaches are essential for understanding ecological processes and detecting the scale of effect. However, nested multiscale approaches retain the effect of the landscape attributes from the smaller spatial scales into the larger ones. Thus, decoupling local vs. regional scales can reveal detailed ecological responses to landscape context, but this multiscale approach is poorly explored. ObjectivesWe evaluated the scale of effect of the forest cover (%) and landscape heterogeneity on Euglossini bees combining coupled and decoupled multiscale approaches. MethodsThe Euglossini males were sampled in forest patches from 15 landscapes within the Atlantic Forest, southeast Brazil. For simplicity, we defined that the coupled approaches represented the local scales and decoupled approaches the regional scales. We decoupled the scales by cutting out the smaller scales inserted into larger ones. We estimated the relationship of the bee community attributes with forest cover (%) and landscape heterogeneity in local and regional scales using Generalized Linear Models. ResultsWe found positive effects of landscape heterogeneity on species richness for regional scales. Forest cover and landscape heterogeneity in local scales showed positive effects on the euglossine abundances. The scale of effect for euglossine richness was higher than species abundances. ConclusionsCombining coupled and decoupled multiscale approaches showed adequate capture of the scale of effect of the landscape composition on bee communities. Therefore, it is of paramount importance to measure the influence of the landscape context on biodiversity. Maintaining landscapes with larger forest cover and spatial heterogeneity is essential to keep euglossine species requirements.

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Ancient and current resilience in the Chengdu Plain: Agropolitan development re-‘revisited’

Urban Studies ◽

10.1177/0042098019843020 ◽

2019 ◽

Vol 57 (7) ◽

pp. 1372-1397 ◽

Cited By ~ 1

Author(s):

Daniel B Abramson

Keyword(s):

Forest Cover ◽

Agricultural Landscape ◽

Landscape Heterogeneity ◽

Irrigation System ◽

Urban Expansion ◽

Flood Management ◽

Ecological Resilience ◽

City Region ◽

Chengdu Plain ◽

Landscape Preservation

The Dujiangyan irrigation system, China’s largest, is one of the world’s most important examples of sustainable agropolitan development, maintained by a relatively decentralised system of governance that minimises bureaucratic oversight and depends on significant local autonomy at many scales down to the household. At its historic core in the Chengdu Plain, the system has supported over 2000 years of near-continuously stable urban culture, as well as some of the world’s highest sustained long-term per-hectare productivity and diversity of grain and other crops, especially considering its high population density, forest cover, general biodiversity and flood management success. During the past decade, rapid urban expansion has turned the Chengdu Plain from a net grain exporter into a grain importer, and has radically transformed its productive functioning and distinctive scattered settlement pattern, reorganising much of the landscape into larger, corporately-managed farms, and more concentrated and infrastructure-intensive settlements of non-farming as well as farming households. Community-scale case studies of spatial-morphological and household socio-economic variants on the regional trend help to articulate what is at stake. Neither market-driven ‘laissez-faire’ rural development nor local state-driven spatial settlement consolidation and corporatisation of production seem to correlate well with important factors of resilience: landscape heterogeneity; crop diversity and food production; permaculture; and flexibility in household independence and choice of livelihood. Management of the irrigation system should be linked to community-based agricultural landscape preservation and productive dwelling, as sources of adaptive capacity crucial to the social-ecological resilience of the city-region, the nation and perhaps all humanity.

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Landscape Structure Effects on Bee and Wasp Assemblages in a Semiarid Buffer Zone

Landscape Online ◽

10.3097/lo.201976 ◽

2019 ◽

Vol 76 ◽

pp. 1-17 ◽

Cited By ~ 1

Author(s):

Lilian Maria Araujo Flores ◽

Lorenzo Roberto Sgobaro Zanette ◽

Danilo Boscolo ◽

Francisca Soares Araújo

Keyword(s):

Landscape Structure ◽

Landscape Heterogeneity ◽

Buffer Zone ◽

Spatial Arrangement ◽

Landscape Composition ◽

Landscape Configuration ◽

Resource Limited ◽

Conservation Actions ◽

Landscape Units ◽

Vegetation Loss

Understanding the effects of anthropogenic changes on groups that perform key ecosystem services, such as pollination and pest control, is essential for conservation and maintenance of these groups in landscapes. We aimed to understand how landscape heterogeneity and the natural vegetation loss affect the diversity of bees, wasps and their parasitoids in a resource limited semiarid environment. We sampled bees and wasps that nest in pre-existing cavities in 20 landscapes, for two years, in Ubajara National Park, in northeastern of Brazil. We recorded eleven species of bees, nine of wasps and six of parasitoids in 657 trapnests. Landscape heterogeneity had different effects on bees, wasps and their parasitoids. Landscape configuration had stronger effect than composition. Bee abundance decreased according to the complexity of the spatial arrangement of landscape units, while wasp abundance increased. Our study shows that in semiarid regions some species may have different responses to landscape structure from those found in other regions. The spatial patterns described here have important implications for conservation of these essential biological groups, indicating that conservation actions for these groups should associate both landscape composition and configuration to increase the provision of resources and to facilitate the access to resources throughout the year.

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Correlation between landscape structure and distribution of Javan Pangolin (Manis javanica) in an extreme landscape

Biodiversitas Journal of Biological Diversity ◽

10.13057/biodiv/d220248 ◽

2021 ◽

Vol 22 (2) ◽

Author(s):

SUSANTI WITHANINGSIH ◽

Parikesit PARIKESIT ◽

ANWAR NASRUDIN

Keyword(s):

Negative Correlation ◽

Landscape Structure ◽

Forest Cover ◽

Landscape Heterogeneity ◽

Pearson Correlation ◽

Strong Negative Correlation ◽

Manis Javanica ◽

Weak Negative Correlation ◽

Ecological Landscape ◽

Linear Regressions

Abstract. Withaningsih S, Parikesit, Nasrudin A. 2021. Correlation between landscape structure and distribution of Javan Pangolin (Manis javanica) in an extreme landscape. Biodiversitas 22: 920-932. The Javan Pangolin (Manis javanica) is a unique mammal with hard scales and can roll over when threatened. However, the study of Javan pangolin ecology, particularly using an ecological landscape approach, is limited. Here, a spatial analysis of the presence and distribution of Javan pangolins living in an extreme landscape in Rongga Sub-district, West Bandung District was conducted and was correlated to the landscape structure using a landscape metric approach. A descriptive method was used in conjunction with quantitative statistical analyses using simple linear regressions based on the Pearson correlation coefficient. The variables were features of the extreme landscape structure and the number of Javan pangolin animal signs at the sampling sites. The seven sample sites had variations in land cover classes, and the landscape structure affected the distribution of the Javan pangolins. The pangolin distribution showed a strong, negative correlation with the number of patch types (R2 = 0.628) and a weak, negative correlation with both the landscape heterogeneity (R2 = 0.012) and the percentage of forest cover (R2 = 0.136). Together, the landscape heterogeneity, the number of patch types and the percentage of forest cover negatively affected the distribution of Javan pangolins, showing a strong correlation (R2 = 0.799).

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Diversity of butterflies in the agricultural landscape: the role of farming system and landscape heterogeneity

Ecography ◽

10.1034/j.1600-0587.2000.230611.x ◽

2000 ◽

Vol 23 (6) ◽

pp. 743-750 ◽

Cited By ~ 19

Author(s):

Ann-Christin Weibull ◽

Jan Bengtsson ◽

Eva Nohlgren

Keyword(s):

Agricultural Landscape ◽

Landscape Heterogeneity ◽

Farming System

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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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