Publications

Surface soil eutrophication hinders ecological restoration projects by favouring communities of low biodiversity. This study assesses the effectiveness of a novel technique known as topsoil inversion that may promote recovery from eutrophication. Topsoil inversion is undertaken by a deep plough, which buries 30 cm of topsoil under approximately 40 cm of subsoil. The main study site is within new community woodland on former agricultural land. It comprises deep ploughed and conventionally ploughed plots, to compare two planting types: wildflowers only, and wildflowers with trees. This presentation will discuss some preliminary findings of the effect of topsoil inversion on soil properties and plant tissue nutrient content. Surface soil fertility is lowered following inversion treatment, and this appears to affect plant nutrient sequestration. These results suggest that topsoil inversion has the potential to facilitate ecological restoration on eutrophic soil. This technique may have benefits for restoration projects taking place in a variety of habitats affected by air pollution, including former agricultural land and lowland heaths.

Ellenberg indicator values for plant species are widely used metrics in ecology, providing a proxy measure of environmental conditions, without direct measurements. They integrate environmental conditions over time since species will only persist where conditions are favourable. Ellenberg moisture (F) values summarise the hydrological environment experienced by plants. However, the relationship between indicator values and hydrological metrics appears to be influenced by a range of other abiotic and biotic factors, limiting our ability to fully interpret Ellenberg F. Focussing on Ellenberg F, we evaluated how the unweighted mean plant community F value to hydrology, specifically water table depth, is influenced by other environmental factors, ground cover type and alpha diversity in UK seasonal coastal wetlands (dune slacks). As expected, water table depth had the strongest influence on unweighted mean Ellenberg F. We show that unweighted mean Ellenberg F was more sensitive to changes in water table levels for plant communities that were more nutrient limited, when the organic matter layer was thicker and there was less bare ground cover. Unweighted mean Ellenberg F was consistently lower for a given water table depth, when there was lower atmospheric nitrogen deposition, lower loss of ignition (a measure of organic matter content) and more diverse plant communities. These findings help us to better interpret what Ellenberg F indicator values tell us about hydrological conditions, by understanding the factors which alter that relationship.

The potential to capture additional air pollutants by introducing more vegetation or changing existing short vegetation to woodland on first sight provides an attractive route for lowering urban pollution. Here, an atmospheric chemistry and transport model was run with a range of landcover scenarios to quantify pollutant removal by the existing total UK vegetation as well as the UK urban vegetation and to quantify the effect of large-scale urban tree planting on urban air pollution. UK vegetation as a whole reduces area (population)-weighted concentrations significantly, by 10% (9%) for PM 2.5 , 30% (22%) for SO 2 , 24% (19%) for NH 3 and 15% (13%) for O 3 , compared with a desert scenario. By contrast, urban vegetation reduces average urban PM 2.5 by only approximately 1%. Even large-scale conversion of half of existing open urban greenspace to forest would lower urban PM 2.5 by only another 1%, suggesting that the effect on air quality needs to be considered in the context of the wider benefits of urban tree planting, e.g. on physical and mental health. The net benefits of UK vegetation for NO 2 are small, and urban tree planting is even forecast to increase urban NO 2 and NO x concentrations, due to the chemical interaction with changes in BVOC emissions and O 3 , but the details depend on tree species selection. By extrapolation, green infrastructure projects focusing on non-greenspace (roadside trees, green walls, roof-top gardens) would have to be implemented at very large scales to match this effect. Downscaling of the results to micro-interventions solely aimed at pollutant removal suggests that their impact is too limited for their cost–benefit analysis to compare favourably with emission abatement measures. Urban vegetation planting is less effective for lowering pollution than measures to reduce emissions at source. The results highlight interactions that cannot be captured if benefits are quantified via deposition models using prescribed concentrations, and emission damage costs. This article is part of a discussion meeting issue ‘Air quality, past present and future’.

Urban air pollution is the second highest risk factor for non-communicable diseases. Socioeconomically deprived populations are at greater risk from related adverse health outcomes and often bear the additional burden of living in areas with higher pollution exposure. To reduce this inequality policy makers need to understand the relationship between the location of interventions and improvements in air quality. The 3–30-300 greening rule outlines guidance to improve residents’ access to trees and greenspace. No studies have yet evaluated its implications for reductions in inequalities or co-benefits beyond greenspace access. This paper explores the relationship between exposure to PM2.5 and socioeconomic status in Paris and Aarhus, and the potential impact of the 3–30-300 rule on health inequalities. We use air quality models and socioeconomic data to calculate disparities in access to greenspace and exposure to fine particulate air pollution across subgroups using two land cover scenarios: existing greenspace conditions and potential enhancements following the 3–30 rule. The following socioeconomic data were disaggregated to residential buildings: households in poverty, age group, citizenship, employment, and education. Exposure to air pollution was calculated as the population-weighted average of PM2.5 concentration (µg m−3). The relationship between socioeconomic characteristics and exposure to poor air quality differed in each city: In Paris, populations often considered more vulnerable to adverse health outcomes (unemployed, non-citizens, lower education level, lowest income) were exposed to higher concentrations of PM2.5, (although the relationship with income was nonlinear), whilst both older and younger populations had slightly lower particulate exposure than working age populations. By contrast, in Aarhus, populations with higher socioeconomic status (and by association, lower vulnerability) in terms of income, education, citizenship and employment status, were exposed to higher concentrations of PM2.5, whilst children were the age group least exposed to fine particulates. Increasing greenspace under the 3–30 had contrasting effects on inequities in each city: mitigations improved air quality for all populations in both but, in Paris, the greatest benefit was experienced by those with lower baseline exposure as well as lower vulnerability. In Aarhus larger air quality improvements were experienced by populations with the highest baseline exposure except for the income characteristic. These were not groups expected to be at greater risk of adverse health outcomes. Reductions in PM2.5 concentration can be produced via targeted increases in trees. The impact on public health outcomes depends in part, on the spatial distribution of socioeconomic groups. Somewhat counter-intuitively, the 3–30 rule in both cities gave greater benefit to those with lower vulnerability.

Access to green spaces is limited in urban areas and has proven benefits for the mental health and well-being of residents. However, there remains a paucity of evidence as to how these benefits vary based on a) the attributes of visited sites, b) the characteristics of visitors, and c) the activities undertaken during each visit. To address these evidence gaps, we analysed 10,749 responses to the Adults’ People and Nature Survey (PaNS) for England, a national survey which gathers information on the location and self-reported mental health benefit of a recent green space visit. Our results suggest that women benefit more than men, and benefit varied between age groups – with those aged 40–54 years experiencing the greatest improvement. Larger green spaces and longer visits were associated with greater well-being. Our model also indicates significant positive relationships between reported mental health benefit and frequency of visits, living with a long-term illness, and the following visit activities: watching wildlife, picnicking, running/cycling, and walking. Seasonality was important, with spring visits more likely to result in strong benefit. We identified significant interactions between age and gender, and between visit duration and site area, which supports the conceptual framework that well-being benefits of green space access arise from a web of interrelating factors. Our findings highlight the need for policymakers and planners to ensure urban residents have access to many types of green area to meet their diverse use requirements and mental health needs.

The ECLAIRE project (Effects of Climate Change on Air Pollution Impacts and Response Strategies for European Ecosystems) is a four year (2011-2015) project funded by the EU's Seventh Framework Programme for Research and Technological Development (FP7).

This review was commissioned by Welsh Government (WG) from the Environment and Rural Affairs Monitoring and Modelling Programme (ERAMMP) to provide key evidence of potential benefits and disbenefits of woodland creation, woodland expansion and managing undermanaged woodland, to provide an evidence base to inform the development of a National Forest for Wales. During the commissioning process, WG emphasised that the evidence provided must reflect the collective views of the community by reviewing the literature in an objective way highlighting where evidence is contradictory or weak. Within the time available, evidence of causality of impacts, the likely timescales and magnitude of these impacts should be also be presented, for both positive and negative impacts of woodland expansion and management of undermanaged woodlands. This Evidence Pack should also build on the evidence put forward in the ERAMMP Sustainable Farm Scheme (SFS) (https://erammp.wales/en/resources) which included a range of assessments of the value of intervention measures which promoted trees within a landscape setting for a range of environmental, economic and social outcomes. The required rapid production of the review in four months meant an expert approach of key evidence was expected rather than a systematic review. Key topics to cover were selected, in partnership with WG, focussing on issues that could fundamentally change decision-making going forward. The final agreed list was arranged under a series of high-level subject headings, and the individual reviews published as ERAMMP Reports 33 to 38 and include; Biodiversity; Managing Undermanaged Woodland; Future-proofing our Woodland; Climate Change Mitigation; Ecosystem Services, and Economics and Natural Capital Accounting. An Integrated Assessment was also commissioned to provide a synthesis of cross-cutting themes and dependencies between topics. These ERAMMP reports are all provided as Annexes to this report.

The enormous global burden of vector-borne diseases disproportionately affects poor people in tropical, developing countries. Changes in vector-borne disease impacts are often linked to human modification of ecosystems as well as climate change. For tropical ecosystems, the health impacts of future environmental and developmental policy depend on how vector-borne disease risks trade off against other ecosystem services across heterogeneous landscapes. By linking future socio-economic and climate change pathways to dynamic land use models, this study is amongst the first to analyse and project impacts of both land use and climate change on continental-scale patterns in vector-borne diseases. Models were developed for cutaneous and visceral leishmaniasis in the Americas—ecologically complex sand fly borne infections linked to tropical forests and diverse wild and domestic mammal hosts. Both diseases were hypothesised to increase with available interface habitat between forest and agricultural or domestic habitats and with mammal biodiversity. However, landscape edge metrics were not important as predictors of leishmaniasis. Models including mammal richness were similar in accuracy and predicted disease extent to models containing only climate and land use predictors. Overall, climatic factors explained 80% and land use factors only 20% of the variance in past disease patterns. Both diseases, but especially cutaneous leishmaniasis, were associated with low seasonality in temperature and precipitation. Since such seasonality increases under future climate change, particularly under strong climate forcing, both diseases were predicted to contract in geographical extent to 2050, with cutaneous leishmaniasis contracting by between 35% and 50%. Whilst visceral leishmaniasis contracted slightly more under strong than weak management for carbon, biodiversity and ecosystem services, future cutaneous leishmaniasis extent was relatively insensitive to future alternative socio-economic pathways. Models parameterised at narrower geographical scales may be more sensitive to land use pattern and project more substantial changes in disease extent under future alternative socio-economic pathways.

Urban expansion and ecological restoration policies can simultaneously affect land-cover changes and further affect ecosystem services (ES). However, it is unclear whether and to what extent the distribution and equity of urban ES are influenced by the stage of urban development and government policies. This study aims to assess the quantity and equity of ES under different scenarios in cites of China and Europe. Firstly, we used the Conversion of Land Use and its Effects at Small regional extent (CLUE-S) model to simulate future land cover under three scenarios: business-as-usual (BAU), a market-liberal scenario (MLS), and an ecological protection scenario (EPS). Then using ecosystem service model approaches and the landscape analysis, the dynamics of green infrastructure (GI) fraction and connectivity, carbon sequestration, and PM2.5 removal were further evaluated. The results show that: (1) over the past 20 years, Chinese cities have experienced dramatic changes in land cover and ES relative to European cities. (2) Two metropolises in China, Shanghai and Beijing have experienced an increase in the fraction and connectivity of GI and ES in the long-term built-up areas between 2010 and 2020. (3) EPS scenarios are not only effective in increasing the quantity of ES but also in improving the equity of ES distribution. The proposed framework as well as the results may provide important guidance for future urban planning and sustainable city development.