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Biology subjects

Remme, R. P.

Publications and source records attributed to Remme, R. P..

4 recordsLinked to original sources

Invertebrate species distributions in urban ecosystems are driven by habitat availability, not by anthropogenic drivers

Rapid urbanisation puts pressure on biodiversity by habitat fragmentation and habitat quality among others. These habitat changes are known to affect species dispersal and connectivity and ultimately species distribution in many ecosystems. However, little is known about the changing urban species distributions which in turn influence community assembly. New DNA-based sampling methods combined with species distribution modelling provide a way to quantitatively estimate urban community assembly through assessing many species distributions and their drivers simultaneously. We investigated species distributions of entire communities in the city of The Hague (the Netherlands) by sampling DNA with two distinct methods: collecting data on invertebrate occurrence with traditional trapping (bulk; n = 205) and a novel Environmental DNA method (eDNA; n = 207). After DNA sequencing, species were identified using Operational Taxonomic Units. Subsequently, individual species presence and absence were used in Species Distribution Models (SDMs), based on spatial information on vegetation and anthropogenic influences. The results show a difference in coverage of sampling methods (bulk vs. eDNA), indicating their complementary information. The models on species distributions were generally significantly better than random models (59.5%), and performed well during calibration (90.4%, AUC > 0.70). In contrast, during validation very few SDMs (1.3%, AUC > 0.70) performed adequately in predicting species distributions. Through this novel combination of DNA sampling with SDMs we show that density and structure of vegetation, as well as distance to water are more important for urban invertebrate distribution than direct anthropogenic pressures. This suggests that dispersal is not a limiting factor in The Hagues urban environment. The availability of a variety of urban green infrastructures seems sufficient to attract many of the species observed. Hence, ensuring sufficient green infrastructure in the urban environment should be the first priority to enhance biodiversity in the urban environment. HighlightsO_LIVegetation and water indicators are the most important predictors for accurate assessment of species distribution C_LIO_LIAnthropogenic pressures have lower impact on urban species distributions C_LIO_LIDNA-SDM combinations show potential in guiding urban planners in evidence-based decision making C_LI

ecology↗

Vegetation density is the main driver of insect species richness and diversity in small private urban front gardens

Urbanisation changes the natural ecosystems and vegetation to urban green spaces, and causes insect communities to experience novel challenges for survival. New evidence suggests that urban green spaces, no matter how small, can provide meaningful habitats for insects. Information on design and management of small gardens (<10m2) in dense urban areas is still scarce. In particular, it is hardly known which garden designs provide most benefits to insects. We surveyed 65 small private urban front gardens (=1.7m2) in Amsterdam and The Hague in The Netherlands and measured a series of garden attributes thought to be relevant for general, flower-visiting and herbivorous insect species richness and diversity. Plant coverage and richness were the strongest predictors for insect biodiversity and species richness. We found no support for associations with native vs. exotic plants or garden size. Synthesis and applicationsTo strengthen insect biodiversity in the urban environment, we recommend future design of urban green spaces to focus on maximising coverage and richness of vegetation, potentially even using exotic species to fill in the gaps where native plant species cannot survive. HighlightsO_LISmall urban gardens hold large potential for supporting urban insect communities C_LIO_LITotal vegetation cover was the strongest predictor for insect diversity and richness C_LIO_LIPlant richness was the second strongest predictor, but not for herbivorous insects C_LIO_LIGarden size had no effect on insect diversity or richness C_LIO_LINative vegetation did not impact insect diversity or richness C_LI O_FIG O_LINKSMALLFIG WIDTH=196 HEIGHT=200 SRC="FIGDIR/small/598424v1_ufig1.gif" ALT="Figure 1"> View larger version (41K): org.highwire.dtl.DTLVardef@17e1ad3org.highwire.dtl.DTLVardef@13322forg.highwire.dtl.DTLVardef@43bd23org.highwire.dtl.DTLVardef@136524d_HPS_FORMAT_FIGEXP M_FIG Graphical abstract. Shown are either plus or minus signs indicating a positive or negative trends from the models that predict species richness and Shannon biodiversity of insects, pollinators or herbivores by the design of small urban gardens. *indicates a statistically significant trend at p-value < 0.05. A plus or minus sign without* means a visible statistically non-significant trend. A greyed out square indicates exclusion of the term in the model. A white square indicates non-significant and non-visible trend. C_FIG

ecology↗

Solution to what? Global review of nature-based solutions, urban challenges, and outcomes

In response to multiple societal challenges faced in cities, nature-based solutions (NbS) are gaining prominence as means to support sustainable and resilient urban planning. However, NbS are being implemented in cities around the globe without comprehensive evidence on their effectiveness in addressing urban challenges. Based on a systematic mapping methodology, we synthesized 547 empirical cases of NbS in 197 cities globally, yielding 799 outcomes encompassing biodiversity, health well-being, and regulating ecosystem services. To structure this evidence we developed an urban NbS classification and categories of urban challenges and outcomes. Effectiveness of NbS was assessed through synthesizing which urban challenges are addressed by NbS, which outcomes are generated, and how these outcomes perform compared to alternative solutions. Our analysis suggests that specific urban challenges were mostly linked to closely related outcomes, but rarely to multiple outcomes. Specifically, forests & trees and general parks were commonly used to enhance health and well-being, while grassland and gardens were applied to mitigate biodiversity loss. Furthermore, urban NbS generally yielded positive effects compared to non-NbS, particularly in relation to microclimate mitigation and mental health outcomes. However, we note a scarcity of evidence on multifunctional NbS, especially on studies that report multiple outcomes related to biodiversity and well-being simultaneously. Our study provides a foundation for further understanding NbS effectiveness and can inform urban planners and policymakers with measurable evidenced-based targets for the application of NbS.

ecology↗

A unified urban green infrastructure classification for assessing ecosystem services and biodiversity

Green infrastructure (GI) classifications are widely applied to predict and assess its suitability for urban biodiversity and ecosystem service (ES) provisioning. However, there is no consolidated classification, which hampers elucidating synthesis and consolidated relationships across ES and biodiversity. In this research, we aim to bridge the gap between urban GI research on ES and biodiversity by providing a standardized common classification that enables consistent spatial analysis. We analyzed GI classifications used across five ES and four taxa in scientific literature. GI classes were analyzed based on name, definition and characteristics. Results were used to create a novel classification scheme accounting for both ES and biodiversity. We show that many GI classes are unique to a ES or taxon, indicating a lack of multifunctionality of the classification applied. Among the universally used classes, diversity in their definitions is large, reducing our mechanistic understanding of multifunctionality in GI. Finally, we show that most GI classes are solely based on land-use or land-cover, lacking in-depth detail on vegetation. Through standardization and incorporation of key characteristics, we created a consolidated classification. This classification is fully available through openly-accessible databases. Our consolidated standardized classification accommodates interdisciplinary research on ES and biodiversity and allows elucidating urban biodiversity and ES relationships into greater detail, facilitating cross-comparisons and integrated assessments. This will provide a foundation for future research efforts into GI multi-functionality and urban greening policies.

ecology↗