4 research outputs found

    Empirical Approach for Modelling Tree Phenology in Mixed Forests Using Remote Sensing

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    Phenological events are good indicators of the effects of climate change, since phenological phases are sensitive to changes in environmental conditions. Although several national phenological networks monitor the phenology of different plant species, direct observations can only be conducted on individual trees, which cannot be easily extended over large and continuous areas. Remote sensing has often been applied to model phenology for large areas, focusing mostly on pure forests in which it is relatively easier to match vegetation indices with ground observations. In mixed forests, phenology modelling from remote sensing is often limited to land surface phenology, which consists of an overall phenology of all tree species present in a pixel. The potential of remote sensing for modelling the phenology of individual tree species in mixed forests remains underexplored. In this study, we applied the seasonal midpoint (SM) method with MODIS GPP to model the start of season (SOS) and the end of season (EOS) of six different tree species in Slovenian mixed forests. First, substitute locations were identified for each combination of observation station and plant species based on similar environmental conditions (aspect, slope, and altitude) and tree species of interest, and used to retrieve the remote sensing information used in the SM method after fitting the best of a Gaussian and two double logistic functions to each year of GPP time series. Then, the best thresholds were identified for SOS and EOS, and the results were validated using cross-validation. The results show clearly that the usual threshold of 0.5 is not best in most cases, especially for estimating the EOS. Despite the difficulty in modelling the phenology of different tree species in a mixed forest using remote sensing, it was possible to estimate SOS and EOS with moderate errors as low as <8 days (Fagus sylvatica and Tilia sp.) and <10 days (Fagus sylvatica and Populus tremula), respectively

    Management of nature-based goods and services provisioning from the urban common: a pan-European perspective

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    The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.The role of the urban common (i.e. shared space and resources) in sustainable provisioning of goods and services to city dwellers is discussed in this paper. Focusing on tree-based green infrastructure, the study scope includes three categories of provisioning (woody biomass, food/fibre, and non-timber forest products, i.e. NTFPs), alongside three categories of supporting services (fresh water replenishment, soil nutrient restoration, building preservation). As a first step, prospects of utilizing the urban common as facilitator of nature-based solution to the earmarked provisioning services are evaluated through dedicated literature survey and expert elicitation on perceived impact of environmental change triggers and management interventions (planning and/or governance). This is followed by a structured review of the state of affairs in four European cities (London, Amsterdam, Sofia, Ljubljana), representing different macro-geographical regions with distinct socio-economic drivers in managing these provisioning services. The pan-European expert elicitation exercise noted active management of the urban common as positively impacting on the performance of the majority of provisioning services, while environmental change impacts were found to be overriding and adversely influencing the provisioning of material resources (mainly NTFPs and woody biomass). The four-city case study highlighted some regional peculiarities in connecting the city dwellers to the urban common and identified the need to overcome socio-cultural barriers for enhancing pan-European best practice sharing in the management of goods and services provisioning. This is deemed essential to pave way for an emerging perspective on sustainable utilization of the urban common as an enabler for nature-based solution, making it fit for purpose in meeting the astronomical demands of future urban living

    Estimation of the allergenic potential of urban trees and urban parks: Towards the healthy design of urban green spaces of the future

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    The impact of allergens emitted by urban green spaces on health is one of the main disservices of ecosystems. The objective of this work is to establish the potential allergenic value of some tree species in urban environments, so that the allergenicity of green spaces can be estimated through application of the Index of Urban Green Zones Allergenicity (IUGZA). Multiple types of green spaces in Mediterranean cities were selected for the estimation of IUGZ. The results show that some of the ornamental species native to the Mediterranean are among the main causative agents of allergy in the population; in particular, Oleaceae, Cupressaceae, Fagaceae, and Platanus hispanica. Variables of the strongest impact on IUGZA were the bioclimatic characteristics of the territory and design aspects, such as the density of trees and the number of species. We concluded that the methodology to assess the allergenicity associated with urban trees and urban areas presented in this work opens new perspectives in the design and planning of urban green spaces, pointing out the need to consider the potential allergenicity of a species when selecting plant material to be used in cities. Only then can urban green areas be inclusive spaces, in terms of public health.This work has been made possible thanks to members of the Silva MediterraneaWorking Group on Urban and Peri-Urban Forestry (FAO WG7) and COST Action FP1204 Green Infrastructure approach: linking environmental with social aspects in studying and managing urban forests. Nezha Acil thanks the technical sta of ISESCO park for their help during his first visit to the park. Maria Beatrice Andreucci also thanks students Giada Di Sante, Guglielmo Pirri e Daniele Purini for her course in Environmental Technological Design of the Master degree in Landscape Architecture at Sapienza Università di Roma for participation in the tree inventory and Duilio Iamonico for the tree taxonomy classification review. The research by the Slovenian Forestry Institute was financially supported by the Program and Research group P4-0107 “Forest ecology, biology and technology” funded by the Slovenian Research Agency.info:eu-repo/semantics/publishedVersio

    Survey questionnaires : data collection for understanding management conditions

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    This chapter focuses on the use of questionnaire surveys to quantitatively assess how people's attitudes and behaviours affect land use and land management. Questionnaires are an established method of improving our knowledge of how different land users (e.g. small-scale forest owners or farmers) and the public think about, respond to, and potentially evade issues of interest. The chapter defines questionnaires, describes their design, and discusses how questionnaires from different countries or from a regional context can be compared. In common with other chapters in this book, the goal is to clarify the extent to which the methodology can capture varying contexts and deliver an understanding of information about differences in the areas for which the studies are designed. Figures and tables contain examples from multi-national questionnaires about land management and how questionnaires can be used in monitoring
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