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1.
Ecol Appl ; 30(7): e02144, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32338806

RESUMO

Heterogeneity in quantity and quality of resources provided in the urban matrix may mitigate adverse effects of urbanization intensity on the structure of biotic communities. To assess this we quantified the spatial variation in butterfly richness and abundance along an impervious surface gradient using three measures of urban matrix quality: floral resource availability and origin (native vs. exotic plants), tree cover, and the occurrence of remnant habitat patches. Butterfly richness and abundance were surveyed in 100 cells (500 × 500 m), selected using a random-stratified sampling design, across a continuous gradient of imperviousness in Melbourne, Australia. Sampling occurred twice during the butterfly flight season. Occurrence data were analyzed using generalized linear models at local and mesoscales. Despite high sampling completeness, we did not detect 75% of species from the regional species pool in the urban area, suggesting that urbanization has caused a large proportion of the region's butterflies to become absent or extremely rare within Melbourne's metro-area. Those species that do remain are largely very generalist in their choice of larval host plants. Butterfly species richness and abundance declined with increasing impervious surface cover and, contrary to evidence for other taxa, there was no evidence that richness peaked at intermediate levels of urbanization. Declines in abundance appeared to be more noticeable when impervious surface cover exceeded 25%, while richness declined linearly with increasing impervious surface cover. We find evidence that the quality of the urban matrix (floral resources and remnant vegetation) influenced butterfly richness and abundance although the effects were small. Total butterfly abundance responded negatively to exotic floral abundance early in the sampling season and positively to total floral abundance later in the sampling season. Butterfly species richness increased with tree cover. Negative impacts of increased urbanization intensity on butterfly species richness and abundance may be mitigated to some extent by improving the quality of the urban matrix by enhancing tree cover and the provision of floral resources, with some evidence that native plants are more effective.


Assuntos
Borboletas , Animais , Austrália , Biodiversidade , Ecossistema , Plantas , Urbanização
2.
Water Resour Res ; 53(12): 10139-10154, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29576662

RESUMO

Management of urban hydrologic processes using green infrastructure (GI) has largely focused on stormwater management. Thus, design and implementation of GI usually rely on physical site characteristics and local rainfall patterns, and do not typically account for human or social dimensions. This traditional approach leads to highly centralized stormwater management in a disconnected urban landscape, and can deemphasize additional benefits that GI offers, such as increased property value, greenspace aesthetics, heat island amelioration, carbon sequestration, and habitat for biodiversity. We propose a Framework for Adaptive Socio-Hydrology (FrASH) in which GI planning and implementation moves from a purely hydrology-driven perspective to an integrated socio-hydrological approach. This allows for an iterative, multifaceted decision-making process that would enable a network of stakeholders to collaboratively set a dynamic, context-guided project plan for the installation of GI, rather than a 'one-size-fits-all' installation. We explain how different sectors (e.g., governance, non-governmental organizations, academia, and industry) can create a connected network of organizations that work towards a common goal. Through a graphical Chambered Nautilus model, FrASH is experimentally applied to contrasting GI case studies and shows that this multi-stakeholder, connected, de-centralized network with a co-evolving decision-making project plan results in enhanced multi-functionality, potentially allowing for the management of resilience in urban systems at multiple scales.

3.
J Environ Qual ; 45(1): 215-23, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26828177

RESUMO

Soils in urban green spaces are an important carbon (C) store, but urban soils with a high carbon to nitrogen (C/N) ratio can also buffer N eutrophication from fertilizer use or atmospheric deposition. The influence of vegetation management practices on soil C cycling and C/N ratios in urban green spaces is largely unknown. In 2013, we collected replicate ( = 3) soil samples from tree canopy, tall grass, and short turf grass areas ( = 3) at four random plot locations ( = 4) established in 13 golf courses ( = 13). At each sample point, soil was separated into 0- to 0.1-, 0.1- to 0.2-, and 0.2- to 0.3-m depths (total = 1404). Linear mixed models investigated the relationships between soil properties, vegetation attributes, and green space age. Tree canopy soil was less compacted (1.07 g cm) than grassy areas (1.32 g cm). Similarly, tree canopy soil had mean C/N ratios of 17.2, as compared with between 14.2 and 15.3 in grassy areas. Soil properties in tree canopy areas were best explained by tree basal area and understory vegetation volume. Soil C/N increased with increasing understory vegetation, and the difference in soil C/N between tree canopy and short turf grass areas increased over time. The soil properties in tree canopy areas of urban green space mean they can increasingly buffer the localized use of N fertilizers and atmospheric N deposition. Managers of urban green spaces concerned about N pollution of groundwater and waterways could consider planting trees in suitable topographic locations and promoting understory vegetation and surface litter accumulation.


Assuntos
Carbono/análise , Nitrogênio/análise , Solo/química , Poaceae , Árvores
4.
Sci Total Environ ; 907: 167739, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-37832672

RESUMO

The 3-30-300 rule offers benchmarks for cities to promote equitable nature access. It dictates that individuals should see three trees from their dwelling, have 30 % tree canopy in their neighborhood, and live within 300 m of a high-quality green space. Implementing this demands thorough measurement, monitoring, and evaluation methods, yet little guidance is currently available to pursue these actions. To overcome this gap, we employed an expert-based consensus approach to review the available ways to measure 3-30-300 as well as each measure's strengths and weaknesses. We described seven relevant data and processes: vegetation indices, street level analyses, tree inventories, questionnaires, window view analyses, land cover maps, and green space maps. Based on the reviewed strengths and weaknesses of each measure, we presented a suitability matrix to link recommended measures with each component of the rule. These recommendations included surveys and window-view analyses for the '3 component', high-resolution land cover maps for the '30 component', and green space maps with network analyses for the '300 component'. These methods, responsive to local situations and resources, not only implement the 3-30-300 rule but foster broader dialogue on local desires and requirements. Consequently, these techniques can guide strategic investments in urban greening for health, equity, biodiversity, and climate adaptation.


Assuntos
Características de Residência , Árvores , Humanos , Cidades , Biodiversidade
6.
Z Rheumatol ; 36(7-8): 219-23, 1977.
Artigo em Alemão | MEDLINE | ID: mdl-919797

RESUMO

In 95 Swiss patients with classical ankylosing spondylitis (AS) the tissue antigen HLA-B27 was present in 92.6%, compared with 7.7% in healthy Swiss blood donors. Assuming the prevalence of ankylosing spondylitis in Switzerland to be 1.9 promille, the chance of a Swiss carrier of HLA-B27 to develop a classical form of AS would be only some 2.2%. For diagnostic purposes, HLA typing thus seems to be of very little value, as among the 462 000 Swiss carriers of HLA-B27 there seem to exist no more than 10 800 classical cases with clinically manifest AS. Absence of HLA-B 27 does not exclude ankylosing spondylitis, as 7.4% of the classical cases are HLA-B27-negative. However, the crudely calculated risk to develop AS is 160 times smaller compared to a carrier HLA-B27. Corner stone of the diagnosis therefore remains careful case history and radiological features of a bilateral sacroileitis of at least grade II.


Assuntos
Antígenos HLA/análise , Espondilite Anquilosante/diagnóstico , Adolescente , Adulto , Idoso , Feminino , Frequência do Gene , Teste de Histocompatibilidade , Humanos , Masculino , Pessoa de Meia-Idade , Espondilite Anquilosante/genética , Suíça
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