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Ecological Intelligence

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Ecological Intelligence / Subject

urban ecology

Peer-reviewed Europe

Rome's river was a corridor for some dispersers and a barrier for others

Evidence
Peer-reviewed
Geography
Rome metropolitan region, Italy
System
Urban protected areas / corridor modeling

WHAT THE EVIDENCE SAYS

Researchers modeled protected-area connectivity with circuit and graph theory under nine resistance scenarios representing three dispersal modes. The western and peripheral city sectors were generally more permeable than the center and east. The Tiber River appeared as either connective space or resistance depending on the assumed species' movement strategy. Shared candidate links often followed rivers and urban green spaces.

WHY IT MATTERS / OUR READ

Urban landscape plans should test which animals can actually cross a proposed corridor; a riverbank or park is not universally connected simply because it is green in an aerial image.

CAVEATS / UNCERTAINTY

Results are based on modeled resistance and dispersal assumptions, not observed migration or survival. Rome's urban form and species assemblages limit direct transfer of the identified corridor locations to other cities.

SOURCE

Landscape Ecology — Russo et al. (2026)
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Urban connectivity models suggest that no single green-link map represents all wildlife movement.

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Peer-reviewed Global

Light-pollution evidence is getting strong enough for a mitigation hierarchy—but regulation still lags

Evidence
Peer-reviewed
Geography
Global
System
Terrestrial, freshwater and coastal nightscapes

WHAT THE EVIDENCE SAYS

The review synthesizes ecological effects of artificial light at night from genes through ecosystems and argues that evidence has advanced faster than regulation. It proposes a mitigation hierarchy led by elimination of unnecessary lighting, followed by spatial and temporal controls and then spectral tuning, while identifying major gaps in standardization, long-term effects and multi-stressor interactions.

WHY IT MATTERS / OUR READ

Lighting is infrastructure, and its ecological footprint can be altered through design and operations rather than treated as an unavoidable urban condition. The hierarchy is useful because it favors reducing exposure before optimizing lamp characteristics.

CAVEATS / UNCERTAINTY

This is a review and management framework, not a single comparative trial proving the same hierarchy for every taxon or site. Long-term, network-level and cross-stressor evidence remains limited.

SOURCE

Nature Reviews Biodiversity — review
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A new review prioritizes eliminating unnecessary light first, then spatial and temporal controls, with spectral tuning later in the mitigation hierarchy.

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Urban green space is losing bird functional space before every diversity metric agrees

Evidence
Peer-reviewed urban field survey and trait analysis
Geography
Harbin, Northeast China
System
Urban green space / blue-green network

WHAT THE EVIDENCE SAYS

Bird communities across 24 urban green-space patches were analyzed against a composite urbanization gradient. Species richness declined consistently; two-dimensional functional space occupied by the community also contracted, especially for larger-bodied, higher hand-wing-index and aquatic-associated traits. Functional richness declined too, but that result was sensitive to how residual spatial structure was modeled. Water-body cover, vegetation cover and foliage-height diversity were associated with different functional groups.

WHY IT MATTERS / OUR READ

Urban biodiversity design should not treat every green polygon as equivalent. Water, vertical vegetation structure and blue–green connectivity can retain different parts of the avian trait space, while a single richness score may not reveal which ecological functions are disappearing.

CAVEATS / UNCERTAINTY

The study is cross-sectional and limited to 24 patches in one city. Trait–habitat relationships are associations rather than experimental treatment effects, and the functional-richness result is explicitly model-sensitive.

SOURCE

Journal of Applied Ecology — primary study
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Across 24 Harbin green-space patches, species richness declined with urbanization and occupied trait space contracted, while the functional-richness trend itself was sensitive to spatial modeling.

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Peer-reviewed

Urban dipterocarps in Singapore are carrying distinct but low-diversity ectomycorrhizal communities

Evidence
Peer-reviewed
Geography
Five urban parks, Singapore
System
Tropical urban parks and tree–soil microbiomes

WHAT THE EVIDENCE SAYS

Researchers collected 50 soil and root-system samples from 10 sampling points across five Singapore parks planted with Hopea odorata and characterized ectomycorrhizal fungi using DNA metabarcoding. They identified six genera and 21 operational taxonomic units. Community composition differed among parks while alpha diversity was similar, and measured soil pH and texture were not significantly associated with diversity or composition. Tomentella was the most frequently detected genus.

WHY IT MATTERS / OUR READ

Urban tree planting is also belowground community assembly. A tree species can survive across parks while carrying different fungal partners, so long-term urban-forest performance cannot be inferred from canopy planting lists alone.

CAVEATS / UNCERTAINTY

This is one planted dipterocarp species, 50 samples and five parks. OTU presence does not directly measure fungal function or tree benefit, and unmeasured site history, inoculum sources, management and soil chemistry may explain among-park differences. The study does not establish that low fungal diversity limits tree performance.

SOURCE

Biotropica — primary study
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DNA metabarcoding around planted Hopea odorata in five parks found 21 ectomycorrhizal OTUs; community composition differed among parks even though alpha diversity did not.

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Peer-reviewed Europe

A Glasgow river corridor kept a biological signal through the city—but one popular acoustic index failed the ground-truth

Evidence
Peer-reviewed
Geography
Glasgow, Scotland, United Kingdom
System
Urban riparian corridor / soundscape

WHAT THE EVIDENCE SAYS

Passive acoustic recorders were deployed along a riparian corridor from farmland to central Glasgow and a subset of recordings was manually identified to ground-truth acoustic indices. The Acoustic Complexity Index correlated with geophony rather than ecologically relevant biophony or anthrophony measures and was dropped from subsequent analysis; other indices captured clearer spatial and temporal patterns in avian acoustic activity. River proximity and lower light pollution were associated with more natural acoustic conditions, while dawn-chorus activity declined in urban locations.

WHY IT MATTERS / OUR READ

Urban ecological infrastructure is partly about continuity of process, not simply green acreage. Riparian corridors can retain biological activity through developed landscapes, but the monitoring lesson is equally important: an automated index is useful only after it is calibrated against what is actually in the recordings.

CAVEATS / UNCERTAINTY

Acoustic activity is not a direct census of bird abundance, richness or demographic performance. Index behavior depends on local sound sources and recording conditions, and associations with river proximity or light pollution do not by themselves establish causation.

SOURCE

BMC Ecology and Evolution
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Passive recorders along a farm-to-city riparian gradient found reduced avian acoustic activity in more urban settings, while manual checks showed the Acoustic Complexity Index was not tracking the ecological signal the team needed.

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Peer-reviewed Europe

Urban versus rural did not explain these park-bee metrics as well as flowers inside the park

Evidence
Peer-reviewed
Geography
22 urban and rural parks in Central Europe
System
Managed parkland / urban-rural green space

WHAT THE EVIDENCE SAYS

Researchers recorded 5,763 wild bees representing 188 species across 22 urban and rural parks. Bee-forage-plant cover was the strongest predictor of abundance and species richness and was associated with lower Jaccard dissimilarity and turnover. Landscape type, floral richness, bare ground, park age and analyzed landscape-scale gradients showed no significant effects on the community metrics; functional dispersion and trait–environment associations also showed no significant responses.

WHY IT MATTERS / OUR READ

‘Urban’ is not automatically the ecological treatment. At the scale of managed parks, local resource condition can explain more of the observed pollinator response than a coarse urban–rural label. That argues for measuring the habitat a species actually experiences rather than using settlement category as a proxy for it.

CAVEATS / UNCERTAINTY

This is an observational study of 22 parks in one Central European setting. Non-significant landscape effects are not proof that surrounding landscape is irrelevant in other systems or at other scales, and forage cover may covary with unmeasured management or habitat factors.

SOURCE

Apidologie
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Across 22 Central European parks, forage-plant cover predicted wild-bee abundance and richness; landscape type and several broader gradients were not significant predictors of the analyzed metrics.

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North America

A Milwaukee biofilter captured sediment and phosphorus while exporting some dissolved pollutants

Evidence
Government technical report / three-year field monitoring
Geography
Milwaukee, Wisconsin, USA
System
Urban stormwater biofiltration

WHAT THE EVIDENCE SAYS

USGS monitored an urban biofiltration system from 2022–2024. The system reduced runoff volume by about 86%, peak flow by 92%, suspended sediment by 99% and total phosphorus by 86%, with strong retention of several particulate metals. Dissolved phosphorus and some dissolved metals showed net export, and road-salt sodium also moved through the system differently from particulate pollutants.

WHY IT MATTERS / OUR READ

Green infrastructure is not one treatment effect. A biofilter can perform exceptionally well for hydraulic control and particulate pollutants while exporting or weakly retaining dissolved constituents, so post-occupancy ecological performance should be assessed by pollutant form and season rather than a single 'stormwater treated' label.

CAVEATS / UNCERTAINTY

This is one monitored facility and performance depends on media, age, inflow chemistry, maintenance and climate. Loads and concentrations can tell different stories, and the study does not establish that every biofilter will reproduce these efficiencies or export patterns.

SOURCE

U.S. Geological Survey
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Three years of paired inlet–outlet monitoring found strong runoff, sediment and particulate-pollutant retention, but dissolved phosphorus, sodium and some metals did not follow the same pattern.

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Peer-reviewed North America

Urban connectivity may work differently once organisms are allowed to evolve

Evidence
Peer-reviewed
Geography
100 metropolitan areas, United States
System
Urban landscapes and plant–pollinator metacommunities

WHAT THE EVIDENCE SAYS

Across 100 U.S. metropolitan regions, urban landscapes had lower heterogeneity and forest aggregation and higher aggregation of developed land than non-urban landscapes. A proof-of-concept spatial eco-evolutionary plant–pollinator model then showed that heterogeneity and connectivity can delay extinction, but trait evolution and mutualistic feedbacks change the size of those benefits.

WHY IT MATTERS / OUR READ

Green corridors and habitat networks are not static plumbing. If species interactions and traits change in fragmented urban landscapes, design performance may depend on how connectivity shapes both movement and adaptation over time.

CAVEATS / UNCERTAINTY

The empirical landscape analysis does not measure observed extinction outcomes, and the eco-evolutionary result comes from a proof-of-concept model rather than a post-occupancy design experiment. The 100-city U.S. sample may not generalize to other urban forms.

SOURCE

Landscape Ecology
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A 100-city landscape analysis paired with a plant–pollinator model suggests that heterogeneity and connectivity can delay extinction, while evolutionary feedbacks can erode some of that benefit.

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Peer-reviewed

In Wuhan, the cooling value of green space depended on what surrounded it and who lived nearby

Evidence
Peer-reviewed
Geography
Wuhan, China
System
Urban land–water mosaic

WHAT THE EVIDENCE SAYS

A WRF–urban-canopy modeling study of central Wuhan evaluated green-space cooling during a clear, calm July 2018 heatwave at 333-m resolution. Trees generally delivered the highest cooling efficiency, while wind direction, the Yangtze River and the spatial distribution of people and existing green space changed where marginal cooling benefits were greatest.

WHY IT MATTERS / OUR READ

Urban greening is not only an acreage question. Placement, vegetation type, water, airflow and population exposure can change the value of the same area of green space, making heat adaptation a landscape-configuration problem.

CAVEATS / UNCERTAINTY

The results are modeled counterfactuals tied to one heatwave and contemporaneous land-cover and population data. Cooling performance is not a biodiversity measure, and transfer to other cities requires local climate, morphology and water-context validation.

SOURCE

Landscape Ecology
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A 333-m urban-climate model found trees generally cooled more efficiently than grass, but airflow, nearby water, population density and where green space was scarce changed where each hectare mattered most.

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Peer-reviewed

Change the map scale and Hangzhou Bay’s ecological trend changes with it

Evidence
Peer-reviewed
Geography
Hangzhou Bay Urban Agglomeration, China
System
Urban / coastal metropolitan landscape

WHAT THE EVIDENCE SAYS

A Google Earth Engine analysis tracked a remote-sensing ecological index from 2000–2024 at 1-, 3-, 5- and 10-km grids and county scale. The regional RSEI increased by about 0.0423 overall, but the share classified as improving rose from 75.34% at 1 km to 84.25% at county scale, demonstrating how aggregation can hide opposing local trajectories. Land-use intensity was the strongest SHAP contributor in the explanatory model.

WHY IT MATTERS / OUR READ

For metropolitan ecological planning, scale is part of the result. County or city averages can be useful for screening, but site and corridor decisions need nested spatial analysis so local degradation is not erased by improvement elsewhere.

CAVEATS / UNCERTAINTY

RSEI combines greenness, wetness, dryness and surface temperature; it is not a direct biodiversity or ecosystem-integrity measure. The study is observational and cannot assign causal effects to land use or policy, and its machine-learning validation was not designed as a strict spatial or temporal holdout test.

SOURCE

Frontiers in Ecology and Evolution
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A 25-year remote-sensing analysis found coarse administrative units made improvement look more widespread while hiding local opposing trends along urban corridors and the bay.

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Europe

Urban climate infrastructure does not automatically become biodiversity infrastructure

Evidence
Other
Geography
Netherlands / urban applications
System
Urban green-blue infrastructure / nature-based solutions

WHAT THE EVIDENCE SAYS

The authors develop a biodiversity-benefit typology and use literature plus expert judgement to estimate the performance of 14 urban nature-based solutions commonly selected for climate adaptation. Their central finding is a design gap: interventions optimized for heat or water functions may miss habitat, species and human–nature benefits unless biodiversity is an explicit objective.

WHY IT MATTERS / OUR READ

For cities as landscapes, multifunctionality has to be designed rather than assumed. A bioswale, tree system or water feature can be climate infrastructure without necessarily functioning as good habitat.

CAVEATS / UNCERTAINTY

This is a perspective and expert-judgement framework for the Dutch context, not post-occupancy ecological monitoring of the 14 interventions. The scores should guide questions and design criteria, not be treated as measured universal performance rankings.

SOURCE

Frontiers in Sustainability
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A Dutch perspective scores 14 common nature-based solutions against biodiversity functions and argues that climate-adaptation design routinely leaves ecological value on the table.

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Peer-reviewed Latin America & Caribbean

Most of Kingston Harbour’s mangrove carbon is below ground

Evidence
Peer-reviewed
Geography
Kingston Harbour, Jamaica
System
Urban-influenced mangrove forest

WHAT THE EVIDENCE SAYS

Across sampled Kingston Harbour mangroves, belowground tree and soil pools contributed about 92% of total carbon. Mean total ecosystem carbon was 417.9 ± 17.5 Mg C/ha; using about 300 ha of mangrove, the authors estimated roughly 125,373 Mg C stored in vegetation and the top metre of soil, with strong variation among forest areas.

WHY IT MATTERS / OUR READ

Urban mangrove condition cannot be read from canopy appearance alone. Soil and belowground carbon dominate this stock, reinforcing the importance of hydrology, disturbance and soil preservation in urban coastal management.

CAVEATS / UNCERTAINTY

This is a site-specific stock estimate based on sampled forests and extrapolated area, not a rate of current sequestration or proof that every urban mangrove stores similar carbon. One rehabilitated site had shallower sampled soil depth.

SOURCE

Wetlands
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A new carbon baseline for roughly 300 hectares of urban-influenced mangroves estimates 92% of total carbon in belowground tree and soil pools.

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Peer-reviewed Latin America & Caribbean

Bogotá’s bird distributions expose a socioeconomic geography—but habitat still does the ecological work

Evidence
Peer-reviewed
Geography
Bogotá, Colombia
System
Andean metropolitan landscape, urban trees, parks and wetlands

WHAT THE EVIDENCE SAYS

Using eBird records, cadastral land values and spatial regression, researchers found significant positive socioeconomic associations for many of 157 analyzed bird species, with stronger patterns among terrestrial species than aquatic or migratory birds. Urban tree-species richness correlated with bird richness, but explained only about 23% of its variance and did not fully mediate the socioeconomic pattern.

WHY IT MATTERS / OUR READ

The planning lesson is not that wealth itself attracts birds. Socioeconomic geography is entangled with where vegetation structure, habitat quality, wetlands and connectivity are maintained; equitable urban biodiversity planning has to change those ecological conditions rather than simply add generic green cover.

CAVEATS / UNCERTAINTY

This is observational citizen-science analysis, so detection effort, unmeasured habitat structure and spatial confounding remain important. Land values were imputed for some public green spaces, and associations do not establish that income causes biodiversity differences.

SOURCE

Urban Ecosystems
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Spatial models found many terrestrial species more associated with higher-value parts of the city, while aquatic and migratory birds often broke the pattern and tree richness explained only part of the variation.

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Peer-reviewed Europe

In dense cities, bird richness tracked habitat area and connectivity more than urban form type

Evidence
Peer-reviewed
Geography
Gothenburg, Sweden
System
Dense and compact urban landscapes and green infrastructure

WHAT THE EVIDENCE SAYS

Researchers monitored birds across 30 Gothenburg sites in spring 2024: 19 sites representing three dense/compact urban form types and 11 greener reference areas. They recorded 61 species. Median species richness was lower in the dense/compact group than in reference areas (24 versus 33 species; p<0.001), but richness and composition did not differ significantly among the three urban form types themselves. Within the dense/compact sites, larger local natural-habitat area and greater structural connectivity were positively associated with species richness; in the best-supported model, a one-standard-deviation increase in local habitat area corresponded to about 16% higher expected richness and connectivity to about 10% higher richness.

WHY IT MATTERS / OUR READ

The planning signal is not that density is ecologically neutral. Dense and compact sites still underperformed greener reference areas. But within dense urban fabric, the broad form category was less informative than the amount of usable habitat retained locally and its connection to surrounding habitat. That shifts the design question from 'dense or compact?' toward how much habitat survives inside the fabric and whether it remains part of a functioning network.

CAVEATS / UNCERTAINTY

This is a 30-site observational study from one city and one spring season, focused on birds. Structural connectivity is a landscape proxy rather than measured movement, and the strongest 1.8-km scale is likely specific to Gothenburg's landscape. Passive acoustic/occurrence methods can miss infrequently vocalizing species. The associations should not be treated as universal design thresholds or proof that denser development causes the reported differences.

SOURCE

npj Urban Sustainability
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Across 30 Gothenburg sites, dense and compact neighborhoods had fewer bird species than greener reference areas, but the three urban form types did not differ significantly from one another; local natural habitat area and connectivity were the stronger within-city signals.

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Peer-reviewed Asia

Urban bird planning may need different green-space geometry for residents and migrants

Evidence
Peer-reviewed
Geography
Nanjing, China
System
Urban green-space network on the East Asian–Australasian Flyway

WHAT THE EVIDENCE SAYS

Researchers analyzed 116,387 citizen-science bird records from 2022–2024 across Nanjing and compared land-sparing and land-sharing patterns at multiple spatial scales. Concentrated green space tended to support higher diversity, especially for resident birds where total green cover was below about 50%, while more distributed green share could favor migrants in greener landscapes and during non-breeding periods. Human footprint was a consistent predictor, and several sparing-versus-sharing contrasts were not statistically significant.

WHY IT MATTERS / OUR READ

Urban biodiversity design may not have one universal green-space geometry. Residents and migrants use the city differently, and the useful scale of planning may be neighborhood-sized rather than parcel-sized. That argues for network design based on movement and seasonal function, not only total acreage.

CAVEATS / UNCERTAINTY

Citizen-science records are uneven in observation effort and the study is observational. The reported threshold-like patterns should not be treated as a fixed 50% design standard, and effects may differ among cities with different climates, species pools and urban forms.

SOURCE

Landscape Ecology · Original evidence
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More than 116,000 citizen-science records from Nanjing suggest compact green-space concentration and distributed green share can favor different bird groups depending on season and total green cover.

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Government data

Seven nights of listening found six bat species around the Sydney Opera House precinct

Evidence
Government data
Geography
Sydney Opera House, Royal Botanic Garden and The Domain, Sydney, Australia
System
Dense urban waterfront and parkland mosaic

WHAT THE EVIDENCE SAYS

A seven-night acoustic survey in March recorded more than 14,000 bat calls and identified six insectivorous species across the Sydney Opera House, Royal Botanic Garden and Domain precinct. The detections included the vulnerable eastern bent-winged bat, with activity recorded high on the Opera House structure as well as across nearby green space.

WHY IT MATTERS / OUR READ

Cities are not ecological blanks between reserves. Short-duration acoustic monitoring can reveal how built structures, waterfront edges and designed green space participate in habitat networks—and where more systematic urban-biodiversity monitoring may be warranted.

CAVEATS / UNCERTAINTY

Acoustic detections indicate activity, not population size, residency, roosting or reproductive success. Seven nights in one season cannot establish year-round habitat value or compare the precinct with other urban sites.

SOURCE

NSW Environment and Heritage · Monitoring update
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More than 14,000 ultrasonic calls—including a vulnerable bent-winged bat high on the Opera House—show how iconic civic landscapes can also function as nocturnal habitat.

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Peer-reviewed North America

Urbanisation can restructure pond communities without simply reducing biodiversity

Evidence
Peer-reviewed
Geography
New Haven County, Connecticut, USA
System
Urban freshwater ponds

WHAT THE EVIDENCE SAYS

Amphibians and macroinvertebrates were surveyed annually in 32 freshwater ponds from 2019–2024, with microbial communities sampled in 17 ponds in 2024. Community composition shifted with urbanicity, but there was minimal evidence that amphibian or macroinvertebrate richness declined. Wood frog larval density did decline, while pH and temperature were stronger predictors across taxa than urbanicity alone.

WHY IT MATTERS / OUR READ

The common shorthand that more urbanization necessarily means less biodiversity can miss community turnover, vulnerable taxa and the importance of retaining small water bodies. Composition and habitat loss may matter even when total richness looks stable.

CAVEATS / UNCERTAINTY

This is a regional study of 32 ponds, and stable richness can conceal changes in species identity or loss of sensitive taxa. The findings do not imply that urbanization is ecologically benign or that they generalize to every pondscape.

SOURCE

Diversity and Distributions · Original evidence
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Across 32 Connecticut ponds, urbanicity shifted amphibian and macroinvertebrate community composition but provided little evidence of a simple richness decline.

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