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Air contaminants and litter fall decomposition in urban forest areas: The case of S�o Paulo - SP, Brazil

Citation: Lamano Ferreira, M., Portella Ribeiro, A., Rodrigues Albuquerque, C., Ferreira, A.P.D.N.L., Figueira, R.C.L., Lafortezza, R., 2017. Air contaminants and litter fall decomposition in urban forest areas: The case of S�o Paulo - SP, Brazil. Environ. Res. 155, 314–320. doi:10.1016/j.envres.2017.02.023
Lamano Ferreira M., Portella Ribeiro A., Rodrigues Albuquerque C., Ferreira A.P.D.N.L., Figueira R.C.L., Lafortezza R., Environmental Research, 2017
Background Urban forests are usually affected by several types of atmospheric contaminants and by abnormal variations in weather conditions, thus facilitating the biotic homogenization and modification of ecosystem processes, such as nutrient cycling. Peri-urban forests and even natural forests that surround metropolitan areas are also subject to anthropogenic effects generated by cities, which may compromise the dynamics of these ecosystems. Hence, this study advances the hypothesis that the forests located at the margins of the Metropolitan Region of S�o Paulo (MRSP), Brazil, have high concentrations of atmospheric contaminants leading to adverse effects on litter fall stock. Methods The production, stock and decomposition of litter fall in two forests were quantified. The first, known as Guarapiranga forest, lies closer to the urban area and is located within the MRSP, approximately 20 km from the city center. The second, Curucutu forest, is located 70 km from the urban center. This forest is situated exactly on the border of the largest continuum of vegetation of the Atlantic Forest. To verify the reach of atmospheric pollutants from the urban area, levels of heavy metals (Cd, Pb, Ni, Cu) adsorbed on the litter fall deposited on the soil surface of the forests were also quantified. Results The stock of litter fall and the levels of heavy metals were generally higher in the Guarapiranga forest in the samples collected during the lower rainfall season (dry season). Non-metric multidimensional scaling multivariate analysis showed a clear distinction of the sample units related to the concentrations of heavy metals in each forest. A subtle difference between the units related to the dry and rainy seasons in the Curucutu forest was also noted. Multivariate Analysis of Variance revealed that both site and season of the year (dry or rainy) were important to differentiate the quantity of heavy metals in litter fall stock, although the analysis did not show the interaction between these two factors. Precipitation appeared to be an important factor to disperse air pollutants; one method to better regulate this process is the development and integration of green infrastructure at city level, which might contribute to nature-based solutions. Conclusions Results suggest that although the Curucutu forest is not very far from the MRSP, which could result in heavy metal levels similar to those observed in the Guarapiranga forest, the weather conditions, geographic location and rainfall rates might act as efficient physical barriers against the dispersion of pollutants in the urban area. However, it is important to highlight that in the period studied (2012–2013), MRSP presented unusual features during the winter period marked by the highest levels of precipitation which was due to several numbers of frontal systems and also due to their permanence for a couple days in the region. Thus, it is recommended to continue this study in order to obtain a database for characterizing the seasonal variation of air pollution levels in the litter fall and their adverse effects on ecosystem processes in these remnants of the Atlantic Forest. � 2017 Elsevier Inc.

An economic valuation of the recreational benefits associated with nature-based forest management practices

Citation: Nielsen, A. B., Olsen, S. B., & Lundhede, T. (2007). An economic valuation of the recreational benefits associated with nature-based forest management practices. Landscape and Urban Planning, 80(1–2), 63–71.
Landscape and Urban Planning - Vol. 80
The presented study aimed at identifying and assessing public preferences for variations in tree species composition, tree height structure, and presence of dead trees left for natural decay—forest characteristics which are likely to be affected when subjecting stands to nature-based forest management in the temperate, nemoral deciduous zone. Data were collected by means of a questionnaire and by applying choice experiments to elicit people's willingness to pay (WTP). Respondents evaluated a set of hand-drawn forest profile diagrams designed to illustrate different levels and combinations of the mentioned three forest characteristics. The highest WTP (1939 DKK, approx. €262) was found for a scenario of replacing the baseline case stand of even-aged conifers with no dead trees left for natural decay with a mixture of conifers and broadleaves of varying heights, and leaving a few dead trees for natural decay (5 ha−1). However, as the study did not include the importance of variation at forest and landscape levels for public preferences, the elicited WTP ought to be interpreted and used carefully. Based on the study's findings, further research on recreational values associated with conversion to nature-based forest management is suggested.

An impact evaluation framework to support planning and evaluation of nature-based solutions project

An EKLIPSE Expert Working Group report
Nature ‐ Based Solutions (NBS) are solutions to societal challenges that are inspired and supported by nature. The European Commission requested the EKLIPSE project to help building up an evidence and knowledge base on the benefits and challenges of applying NBS. In response to the request, the EKLIPSE Expert Working Group on Nature ‐ based Solutions to Promote Climate Resilience in Urban Areas (EWG) devised the following objectives: 1) To develop an impact evaluation framework with a list of criteria for assessing the performance of NBS in dealing with challenges related to climate resilience in urban areas; 2) To prepare an application guide for measuring how NBS projects fare against the identified indicators in delivering multiple environmental, economic and societal benefits; 3) To make recommendations to improve the assessment of the effectiveness of NBS projects, including the identification of knowledge gaps according to the criteria presented in the impact evaluation framework. This document reports on these three objectives. It is intended to be used as a reference document by members of current and future European projects with an interest in NBS in urban areas, and by practitioners seeking to compare the effectiveness of NBS design, implementation and evaluation. The EWG recognises that the type and intensity of NBS impacts may vary according to the characteristics of the NBS and the context in which they are applied. The intent of this report is not to define NBS, but rather provide examples of indicators and methods for assessing impacts of NBS that may be applied in a range of different ways across urban areas in Europe. As such, the report also identifies the scale at which the indicators are relevant, to guide an assessment of impacts

Assessing allergenicity in urban parks: A nature-based solution to reduce the impact on public health

Citation: Cari�anos, P., Casares-Porcel, M., D�az de la Guardia, C., Aira, M.J., Belmonte, J., Boi, M., Elvira-Rendueles, B., De Linares, C., Fern�ndez-Rodriguez, S., Maya-Manzano, J.M., P�rez-Bad�a, R., Rodriguez-de la Cruz, D., Rodr�guez-Rajo, F.J., Rojo-�beda, J., Romero-Zarco, C., S�nchez-Reyes, E., S�nchez-S�nchez, J., Tormo-Molina, R., Vega Maray, A.M., 2017. Assessing allergenicity in urban parks: A nature-based solution to reduce the impact on public health. Environ. Res. 155, 219–227. doi:10.1016/j.envres.2017.02.015
Cari�anos P., Casares-Porcel M., D�az de la Guardia C., Aira M.J., Belmonte J., Boi M., Elvira-Rendueles B., De Linares C., Fern�ndez-Rodriguez S., Maya-Manzano J.M., P�rez-Bad�a R., Rodriguez-de la Cruz D., Rodr�guez-Rajo F.J., Rojo-�beda J
Urban parks play a key role in the provision of ecosystem services, actively participating in improving the quality of life and welfare of local residents. This paper reports on the application of an index designed to quantify the allergenicity of urban parks in a number of Spanish cities. The index, which records biological and biometric parameters for the tree species growing there, classifies parks in terms of the risk they pose for allergy sufferers, graded as null, low, moderate or high. In this initial phase, the index was applied to 26 green areas in 24 Spanish cities; green areas varied in type (urban park, historical or modern garden, boulevard, square or urban forest), size 1–100 ha), geographical location, species richness, number of trees and tree density (number of trees / ha.). The data obtained were used to calculate the percentage of allergenic species in each park, which varied between 17–67%; density ranged from 100 to 300 trees/ha. The index values recorded ranged from a minimum of.07 to a maximum of.87; a significant correlation was found between index value and both number of trees and tree density. Taking an index value of.30 as the threshold considered sufficient to trigger allergy symptoms in the sensitive population, 12 of the parks studied may be regarded as unhealthy at any time of the year. Corrective measures to mitigate the impact of pollen emissions include the implementation of nature-based solutions at various levels: planning and design, handling and management, and strengthening of urban green-infrastructure elements. The index proved to be a useful tool for environmental analysis, and complies with the principles of portability and scalability central to current and horizon scientific research. � 2017

Assessment of the spatiotemporal effects of land use changes on runoff and nitrate loads in the Talar River

Citation: Kavian, A., Mohammadi, M., Gholami, L., Rodrigo-Comino, J., 2018. Assessment of the spatiotemporal effects of land use changes on runoff and nitrate loads in the Talar River. Water (Switzerland) 10. doi:10.3390/w10040445
Kavian A., Mohammadi M., Gholami L., Rodrigo-Comino J., Water (Switzerland), 2018
This research surveyed the effects of land use changes on flow nitrate pollution in the Talar River (northern Iran), using Landsat images of 1991 and 2013 and the Soil and Water Assessment Tool (SWAT). The results indicated that forest areas decreased by 14.9% and irrigated crops, dry land farming areas, range lands and residential areas increased by 46.8%, 31.1%, 4.7% and 17.5%, respectively. To calibrate and validate the studied period, the Nash Sutcliffe model efficiency (NSE) and coefficient of determination (R2) were applied, ranging from 0.57 to 0.75 and from 0.62 to 0.76 for flow simulation and 0.84 and 0.63 and 0.75 and 0.83 for nitrate simulation, respectively. The results of land use scenarios indicated that respective water flow and nitrate loads increased by 34.4% and 42.2% in 1991-2013 and may even increase by 42.3% and 55.9% in the simulated period of 2013-2050 in all sub-basins. It is likely that the main reason for these results was due to the increase in agricultural activities and the decrease in forestry areas. Our findings showed the useful combination of modelling techniques (land cover changes and SWAT) to develop valuable maps able to design correct land management plans and nature-based solutions for water quality of runoff water harvesting systems in the future. © 2018 by the authors.

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