Urban Ecosystems最新文献

In the debate on the impact of urbanisation on biodiversity, two characteristics of urbanisation have been identified that mainly determine the extent of the impact, namely the level of urbanisation and the landscape context. More recently, it has been theorised that urban sprawl in an intensive agricultural landscape has a positive influence on pollinators by increasing habitat and resource availability. Using the eastern Po Plain (north-eastern Italy) as a model system, we investigated the relationship between attributes of landscape composition and configuration, pollinator richness and visits in 39 randomly selected permanent plots. Contrary to expectations, we found no relationship between urban sprawl and pollinator species richness. Conversely, descriptors of urban sprawl such as landscape heterogeneity and the proportion of urban green spaces had a positive influence on the number of pollinator visits. This suggests that urban sprawl, when occurring in an intensive agricultural land, has a positive effect on the abundance of local pollinator populations, while it may not promote pollinator richness due to limited immigration opportunities in the matrix of intensive agricultural land. Our results emphasise the importance of urban green spaces in supporting pollinator communities, but also the need to improve the heterogeneity and permeability of the landscape matrix for biodiversity to enhance pollinator conservation in human-modified landscapes.

Increasing urbanisation reduces available habitat and increases human-wildlife interactions, presenting social and ecological challenges for many species; however, flexible generalist species, such as the vervet monkey, Chlorocebus pygerythrus, thrive under these pressures. In the urban mosaic, human-food sources represent clumped, monopolisable food that can increase contest competition. Social network analysis (SNA) is a powerful tool to monitor changes in social structure, yet it has rarely been used to study urban wildlife. Using SNA, we investigated the effect of anthropogenic food and human-wildlife interactions on social cohesion in five vervet monkey groups in urban KwaZulu-Natal, South Africa. Over six months, we conducted group scan samples every 30-min on each group and recorded all humans-vervet monkey interactions during dawn to dusk follows. We analysed the effect of foraging on natural and human-related food sources and human-vervet monkey interactions on social network metrics for grooming and aggression at group (density, clustering coefficient and distance) and individual (eigenvector centrality and degree) levels, using linear mixed models. Anthropogenic food influenced almost all social metrics. At the group level, foraging on anthropogenic food was related to increased density and cohesion in both grooming and aggression networks. At the individual level, increasing anthropogenic food affected high-ranking monkeys most: eigenvector centrality and outdegree in aggression networks increased with rank. Social network analysis can be a useful tool to document urban effects on wildlife groups, and aids our understanding of wildlife behavioural flexibility, a key tool in developing educated and effective management strategies.

A variety of stormwater infrastructure such as constructed wetlands, rain gardens, vegetated drainage channels and retention ponds are primarily used for managing water runoff, but these environments can also foster biodiversity. Despite extensive literature about certain taxa (e.g., amphibians, aquatic macroinvertebrates, etc.) found in these human-made environments, the terrestrial plants and invertebrates present there remain understudied. Here, we compared alpha and beta diversity of plant and terrestrial invertebrate communities and assessed the influence of landscape characteristics on their composition in different types of urban stormwater basins and ponds. Plants and terrestrial invertebrates were identified in the main body (excluding the aquatic section) and on the banks of 54 basins and ponds (dry basins, wet basins with and without a water channel and retention ponds) in Quebec City and Trois-Rivières, in Eastern Canada. Results showed poor and homogenous plant and invertebrate communities in dry basins. Wet basins had the highest plant alpha diversity, with more facultative wetland species than the two other types. Wet basins with and without a water channel had similar plant and invertebrate composition, and wet basins and retention ponds were the most heterogeneous. Retention ponds (with permanent water) had distinct communities with fewer plant species than wet basins. The presence of natural areas around the infrastructure significantly influenced communities within a 2000 m and 500 m radius for plant and invertebrate communities, respectively. Wetland plant species were generally found in infrastructure close to natural areas, whereas tolerant and opportunist species were associated with disturbed environments. Our results suggest that enhancing diversity of the stormwater basins and ponds at the regional and local (microhabitat) scales has the potential to maximize diversity of plants and terrestrial invertebrates.

Urbanisation results in the loss and alteration of natural wetlands and ponds. However, garden ponds in cities and towns can potentially act as rich reservoirs of aquatic biodiversity and stepping stones for dispersal. Homeowners with a range of different motivations, including biodiversity values, install garden ponds. Here, our main aim was to study whether the design and management choices of garden pond owners depended on the location of ponds (capital city vs. countryside), when ponds were installed (pond age), or whether fish were introduced. We surveyed 834 garden pond owners across Hungary using a citizen science questionnaire, asking questions on pond size, location, construction date and materials, vegetation structure, introduction of fish and management practices. From 753 validated responses, we found that the introduction of fish into ponds and high urbanisation were strongly associated with local features and management practices, especially large ponds with a water circulation feature, irrespective of pond age. A typical garden pond in Hungary is ~ 20 m², < 10 years old, made of rubber lining, contains fish, aquatic vegetation and circulating water, and is actively managed. There was a spatial separation of ponds based on local features between ponds in the capital city (Budapest) and elsewhere. These findings suggest that garden pond owners in the city were more likely to make different choices in pond design and management compared to owners in regional areas. Our results also suggest that pond owners may primarily select management practices to improve habitat quality for ornamental fish. Our findings have important implications for maintaining aquatic biodiversity in urban areas, where garden ponds may be the only aquatic habitat available.

The ecosystem services concept has been studied in rural contexts but not as much in urban landscapes, particularly for aquatic ecosystems in Africa. There is little knowledge of how people perceive ecosystem services (ES) supplied by rivers in urban centres and the factors influencing their perceptions. To fill this gap, the research presented here addresses two objectives: 1) to assess local communities’ perception and knowledge of different types of ecosystem services of an urban river in South Africa, 2) to assess the influence of particular demographic characteristics (age and gender), socio-economic characteristics (education, housing type, income, and years of residence), and prior knowledge of the ecosystem services concept on people’s perception of the ecosystem services provided by the Swartkops River in the Eastern Cape of South Africa. To address these objectives, a team of ten trained field staff collected 181 surveys between May–June 2021 in communities within the river catchment. We used multinomial logit models to analyse the relationships between demographic and socio-economic variables, and people’s perception of ecosystem services. For the majority of the ecosystem services, there was almost an equal split between the perception “sometimes” and “never” that the river provides a particular ecosystem service, and people were less likely to say that the river always provide a particular service. Prior knowledge of the ecosystem services concept, years of residence, age, income and housing type significantly influence people’s perception of ecosystem services. Prior knowledge, was important for the intangible services, whereas years of residence was more important for tangible services with direct use value. Level of formal education was not a significant variable. An important implication of this study is that ecological interventions can be designed through an understanding of factors influencing people’s perceptions of ecosystem services.

Monitoring species distribution and abundance accurately and efficiently are vital for conservation efforts. Next-generation sequencing and DNA metabarcoding using environmental DNA (eDNA) allow for the simultaneous identification of multiple species in one sample, enabling swift biodiversity assessment in complex ecosystems. However, most eDNA studies focus on aquatic organisms and ecosystems.This study’s main objective was to use eDNA metabarcoding to monitor mammal and bird species in an urban ecological park. The chosen study site was Gildong Ecological Park, Seoul, South Korea, with a total area of 80,000 m² divided into three marsh area, a forested mountain area, and a rural experience learning center. Water sampling occurred five times from August to September, yielding 65 samples from three park sections. We employed MiMammal and MiBird primers targeting mitochondrial 12 S to investigate mammals and birds, serving as pivotal biological indicators within urban ecosystems.Metabarcoding revealed the presence of 73% (11/15) and 67% (represented 67% of the total 6268 individual) of the dominant mammalian and avian species, respectively, known to inhabit the park, compared to the results of traditional surveys. The mountain samples (1.51) and marsh samples (2.32) had significantly different median read counts when including all species; however, the same comparison within each taxonomic group yielded no statistically significant differences. Though we detected species differences using eDNA across summer, autumn, and winter monitoring, no statistically significant differences were found among seasons within the park. However, the park’s area is relatively small for detecting variations in eDNA. This might be because there is a lot of animal activity throughout the study site and/or a limited influence of microhabitats. These results could provide valuable insights for using eDNA to monitor animals in urban ecological parks.

Invasive alien plants (IAPs) are rapidly increasing around the world, mainly due to land transformation, climate change, and urbanisation. Whilst urban areas are highly susceptible to invasion by IAPs, crucial information on the distribution and abundance of woody invaders in small towns is limited. Here, we determined the distribution and abundance of woody IAPs across different suburbs and land use types in 12 small towns in the Eastern Cape province of South Africa. We enumerated 38 427 individual woody IAPs, and their abundance and distribution varied across surveyed towns. Although species such as Melia azedarach, Pinus elliotti, Jacaranda mimosifolia, Eucalyptus camaldulensis, and Ligustrum lucidum were the most distributed, species density varied across towns. More than half of the woody IAPs were identified in affluent (56%) suburbs compared to the townships (23%), Central business district (CBD) (16%), and low-income housing neighbourhoods (5%). There were significant differences in woody IAPs distribution across different land use types, with more than half (54%) found in the residential areas compared to road verges (32%) and public urban green spaces (14%). Some socio-economic and environmental predictors such as town population, mean temperature, unemployment rate, and Gross domestic product (GDP) showed significant and positive correlations with woody IAPs species richness and density. Our findings suggest an uneven spatial distribution and diversity of woody IAPs across the different small towns, suburbs, and land use types in the region. It is recommended that small towns in South Africa need financial and human resources support to effectively manage IAPs.

Interactions between ants and plants can form complex ecological networks, which may have their structure affected by human-induced habitat modification, such as urbanization. In this study, we investigated if the species diversity and the network topology of ant-plant co-occurrence networks (facultative associations between plants and ants) differs between remnants of Neotropical savannas. We sampled 12 savanna fragments (cerrado sensu stricto) in wild, rural and urban areas of Minas Gerais, Brazil. In total, the 12 ant-plant interaction networks were composed by 65 ant species, 83 plant species and 432 distinct interactions. We observed that in addition to variations in species composition, wild areas exhibited higher richness and abundance of ants compared to urban areas. However, our results show no variation in the specialization, modularity, and nestedness of ant-plant co-occurrence networks among urban, rural, and wild areas. Despite changes in species diversity, ant-plant interactions maintain consistent organization across studied environments, showcasing resilience to anthropogenic disturbances similar to that observed in wild remanants.

Urban expansion has emerged as a pervasive driver of biodiversity loss in Mexican cities due to shifts in landscape composition and configuration. Hence, the preservation of forest cover, green spaces and isolated trees assume a critical role in conserving the biodiversity within urban areas. We compared mammal assemblages across 520 sites in Mexico City examining the impact of local vegetation and site characteristics (e.g., patch size, isolation distance) on diversity patterns. Then, we used a generalized linear model to evaluate the relationship between mammal assemblages (including both alpha and beta diversities) and the level of structural and functional connectivity across the landscape. We collected 5,063 records of 38 species from the sampled sites. Mammalian richness ranged from 1 to 9 spp./site, and the mean of taxonomic and functional (Functional Distance [MFD]) alpha diversities were 1.9 ± 1.3 spp./site and 0.41 ± 0.60 MFD/site, respectively. The average size of habitat fragments was 0.41 hectares, and the percent forest cover per site ranged from 0.5 to 100%. Both species and functional alpha diversities were different among the land-use and vegetation types (including protected vs. non-protected areas). There was a clear distinction (β value > 0.40) in species composition across the landscape, which was positively related to geographical distance and negatively related to connectivity between sites. We identified four main patches especially important to connectivity across the city and argue that conserving them is critical for restoring key components of biodiversity and ecosystem services in urban and peri-urban areas of Mexico City.

Reflecting on the insights from research development within Urban Biodiversity and Design Network (URBIO), this paper attempts to link the consequences of current global changes (ongoing urbanization, biodiversity loss, land-use changes, globalization, etc.) to the emergence and outbreaks of the COVID-19 pandemic. It analyses the main outcomes of the URBIO webinar (December 2021) and the URBIO conference (November 2022) and the results of the questionnaire survey among the URBIO experts on the impact of COVID-19 on the biodiversity, design and society in their local contexts as well as on the ongoing and future URBIO research directions. The survey also enabled to explore and assess a wide diversity of human-nature interactions as well as the novel actions and adaptation strategies established to have positive outcomes for both humans and nature. The results revealed the following aspects associated with the COVID-19 pandemic: silence, social distancing, isolation, conflict ideologies, and declined recreational and other human activities. Experts noticed the increase of urban green space visitation and interest in nature. The majority of the experts confirmed the impact (both positive and negative) of the COVID-19 on biodiversity and environment. General positive aspects refer to the value/significance of nature and biodiversity/wildlife and especially the contact with nature (“time outdoor”, “time spent with family”, “inspiration from nature” and “enjoying nature”). The positive consequence of the COVID-19 measures was also the improvement of wildlife habitats and the increase of spontaneous flora as well as fauna species. Experts confirmed the lower/decreased level of pollution, noise, traffic, light, anthropogenic pressure/impact, number of tourists, vehicles as well as less garbage. The analysis of leading research themes among the URBIO conference participants confirmed that the biggest number of presenters and participants were on the topic of biodiversity integration in urban planning, green infrastructure, and landscape design projects. Another popular theme was ecological restoration and urban wildlife and plant biodiversity. One particular research direction that emerged recently and clearly pronounced at URBIO 2022 was urban biodiversity in times of climate change and post-pandemics.