The role of forest in mitigating the impact of atmospheric dust pollution in a mixed landscape

The role of park size on ecosystem services in urban environment: a review

Urban parks play an important role in urban ecosystems with multifunctional services. Park size is one of the important attributes to explain the potential capacity of urban parks. In recent years, the number of studies that focus on the relationship between park size and ecosystem services in the context of ecosystem services has been increasing. This study aims to focus on investigating the relationship between ecosystem services and urban park size. The Web of Science online databases were searched using the keywords "green space", "size" and "urban" as well as related terms. A total of 129 papers meeting the inclusion criteria were examined within the scope of the research aims. The results obtained from the systematic search were summarized and presented in the three categories with sub-categories: (i) cultural services with sub-categories of physical activity (n = 42) and housing prices (n = 10), (ii) supporting services with sub-categories of fauna (n = 44), and flora (n = 3) and (iii) regulating services with sub-categories of microclimate (n = 25) and air quality (n = 5). The results indicated that park size influences a wide range of services by providing more spaces for physical activities, increasing housing prices, creating habitats for birds, insects, and bats, and effects on their richness, diversity and density, increasing the cooling effect capacity and reducing air pollution of urban parks. In conclusion, a comprehensive approach is needed, recognizing the potential of both large and small green spaces to optimize ecosystem services delivery, promote resilience, and enhance urban well-being. This includes considering supply and demand aspects and improving measurement methods. Furthermore, exploring optimal improvements across diverse park sizes remains a promising avenue for research, contributing to the development of more efficient urban green spaces.

Macro-Morphological Traits of Leaves for Urban Tree Selection for Air Pollution Biomonitoring: A Review

Urban trees provide different ecosystem benefits, such as improving air quality due to the retention of atmospheric particulate matter (PM) on their leaves. The main objective of this paper was to study, through a systematic literature review, the leaf macro-morphological traits (LMTs) most used for the selection of urban trees as air pollution biomonitors. A citation frequency index was used in scientific databases, where the importance associated with each variable was organized by quartiles (Q). The results suggest that the most biomonitored air pollutants by the LMTs of urban trees were PM between 1-100 µm (Q1 = 0.760), followed by O₃ (Q2 = 0.586), PM_2.5 (Q2 = 0.504), and PM₁₀ (Q3 = 0.423). PM was probably the most effective air pollutant for studying and evaluating urban air quality in the context of tree LMTs. PM_2.5 was the fraction most used in these studies. The LMTs most used for PM monitoring were leaf area (Q1) and specific leaf area (Q4). These LMTs were frequently used for their easy measurement and quantification. In urban areas, it was suggested that leaf area was directly related to the amount of PM retained on tree leaves. The PM retained on tree leaves was also used to study other f associated urban air pollutants associated (e.g., heavy metals and hydrocarbons).

Modeling the provision of air-quality regulation ecosystem service provided by urban green spaces using lichens as ecological indicators

The UN Sustainable Development Goals states that urban air pollution must be tackled to create more inclusive, safe, resilient and sustainable cities. Urban green infrastructures can mitigate air pollution, but a crucial step to use this knowledge into urban management is to quantify how much air-quality regulation can green spaces provide and to understand how the provision of this ecosystem service is affected by other environmental factors. Considering the insufficient number of air quality monitoring stations in cities to monitor the wide range of natural and anthropic sources of pollution with high spatial resolution, ecological indicators of air quality are an alternative cost-effective tool. The aim of this work was to model the supply of air-quality regulation based on urban green spaces characteristics and other environmental factors. For that, we sampled lichen diversity in the centroids of 42 urban green spaces in Lisbon, Portugal. Species richness was the best biodiversity metric responding to air pollution, considering its simplicity and its significative response to the air pollutants concentration data measured in the existent air quality monitoring stations. Using that metric, we then created a model to estimate the supply of air quality regulation provided by green spaces in all green spaces of Lisbon based on the response to the following environmental drivers: the urban green spaces size and its vegetation density. We also used the unexplained variance of this model to map the background air pollution. Overall, we suggest that management should target the smallest urban green spaces by increasing green space size or tree density. The use of ecological indicators, very flexible in space, allow the understanding and the modeling of the provision of air-quality regulation by urban green spaces, and how urban green spaces can be managed to improve air quality and thus improve human well-being and cities resilience.

Protected Natural Areas: In Sickness and in Health

Numerous studies show the benefits that contact with the natural environment have for human health, but there are few studies on the role of Protected Natural Areas (PNAs), either from the preventive point of view or on their potential benefits, on individuals with health problems. A study was made of the relationship between the visitation of Montseny Natural Park and Biosphere Reserve and health, from the perspective of a population group with different diseases. A total of 250 patients resident in the areas near the park were surveyed, recording their beliefs about the benefits of nature, as well as the reasons for visiting and the activities associated with health that they carried out in the park. The pure air is the most valued benefit (27.2%), particularly for those with allergies. The majority (57%) visit the park for health reasons. High levels (82%) of exercise are recorded, especially by patients with heart diseases (85%), and 65% exercised in the park. More physical activity is mentioned among those that visit the park most often, particularly among those that carried it out for health reasons. Plants were collected for medicinal use by 39.6%. The study confirmed the significant role of the Montseny Natural Park and Biosphere Reserve as a health resource for individuals with diseases that live near it. It also corroborates the beneficial effects that the PNA provide in human health.

Chemical and magnetic analyses on tree bark as an effective tool for biomonitoring: A case study in Lisbon (Portugal)

Tree bark has proven to be a reliable tool for biomonitoring deposition of metals from the atmosphere. The aim of the present study was to test if bark magnetic properties can be used as a proxy of the overall metal loads of a tree bark, meaning that this approach can be used to discriminate different effects of pollution on different types of urban site. In this study, the concentrations of As, Cd, Co, Cu, Fe, Mn, Ni, P, Pb, V and Zn were measured by ICP-OES in bark samples of Jacaranda mimosifolia, collected along roads and in urban green spaces in the city of Lisbon (Portugal). Magnetic analyses were also performed on the same bark samples, measuring Isothermal Remanent Magnetization (IRM), Saturation Isothermal Remanent Magnetization (SIRM) and Magnetic Susceptibility (χ). The results confirmed that magnetic analyses can be used as a proxy of the overall load of trace elements in tree bark, and could be used to distinguish different types of urban sites regarding atmospheric pollution. Together with trace element analyses, magnetic analyses could thus be used as a tool to provide high-resolution data on urban air quality and to follow up the success of mitigation actions aiming at decreasing the pollutant load in urban environments.

Green spaces are not all the same for the provision of air purification and climate regulation services: The case of urban parks

The growing human population concentrated in urban areas lead to the increase of road traffic and artificial areas, consequently enhancing air pollution and urban heat island effects, among others. These environmental changes affect citizen's health, causing a high number of premature deaths, with considerable social and economic costs. Nature-based solutions are essential to ameliorate those impacts in urban areas. While the mere presence of urban green spaces is pointed as an overarching solution, the relative importance of specific vegetation structure, composition and management to improve the ecosystem services of air purification and climate regulation are overlooked. This avoids the establishment of optimized planning and management procedures for urban green spaces with high spatial resolution and detail. Our aim was to understand the relative contribution of vegetation structure, composition and management for the provision of ecosystem services of air purification and climate regulation in urban green spaces, in particular the case of urban parks. This work was done in a large urban park with different types of vegetation surrounded by urban areas. As indicators of microclimatic effects and of air pollution levels we selected different metrics: lichen diversity and pollutants accumulation in lichens. Among lichen diversity, functional traits related to nutrient and water requirements were used as surrogates of the capacity of vegetation to filter air pollution and to regulate climate, and provide air purification and climate regulation ecosystem services, respectively. This was also obtained with very high spatial resolution which allows detailed spatial planning for optimization of ecosystem services. We found that vegetation type characterized by a more complex structure (trees, shrubs and herbaceous layers) and by the absence of management (pruning, irrigation and fertilization) had a higher capacity to provide the ecosystems services of air purification and climate regulation. By contrast, lawns, which have a less complex structure and are highly managed, were associated to a lower capacity to provide these services. Tree plantations showed an intermediate effect between the other two types of vegetation. Thus, vegetation structure, composition and management are important to optimize green spaces capacity to purify air and regulate climate. Taking this into account green spaces can be managed at high spatial resolutions to optimize these ecosystem services in urban areas and contribute to improve human well-being.

Ecosystem services: Urban parks under a magnifying glass

Urban areas' population has grown during the last century and it is expected that over 60% of the world population will live in cities by 2050. Urban parks provide several ecosystem services that are valuable to the well-being of city-dwellers and they are also considered a nature-based solution to tackle multiple environmental problems in cities. However, the type and amount of ecosystem services provided will vary with each park vegetation type, even within same the park. Our main goal was to quantify the trade-offs in ecosystem services associated to different vegetation types, using a spatially detailed approach. Rather than relying solely on general vegetation typologies, we took a more ecologically oriented approach, by explicitly considering different units of vegetation structure and composition. This was demonstrated in a large park (44ha) located in the city of Almada (Lisbon metropolitan area, Portugal), where six vegetation units were mapped in detail and six ecosystem services were evaluated: carbon sequestration, seed dispersal, erosion prevention, water purification, air purification and habitat quality. The results showed that, when looking at the park in detail, some ecosystem services varied greatly with vegetation type. Carbon sequestration was positively influenced by tree density, independently of species composition. Seed dispersal potential was higher in lawns, and mixed forest provided the highest amount of habitat quality. Air purification service was slightly higher in mixed forest, but was high in all vegetation types, probably due to low background pollution, and both water purification and erosion prevention were high in all vegetation types. Knowing the type, location, and amount of ecosystem services provided by each vegetation type can help to improve management options based on ecosystem services trade-offs and looking for win-win situations. The trade-offs are, for example, very clear for carbon: tree planting will boost carbon sequestration regardless of species, but may not be enough to increase habitat quality. Moreover, it may also negatively influence seed dispersal service. Informed practitioners can use this ecological knowledge to promote the role of urban parks as a nature-based solution to provide multiple ecosystem services, and ultimately improve the design and management of the green infrastructure. This will also improve the science of Ecosystem Services, acknowledging that the type of vegetation matters for the provision of ecosystem services and trade-offs analysis.