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Continuous water resources monitoring is needed for sustainable urban water supply. Remote sensin... more Continuous water resources monitoring is needed for sustainable urban water supply. Remote sensing techniques have proven useful for monitoring some water qualitative parameters with optical characteristics. The study area was the Marateca reservoir in central inland Portugal. The aims were the following: (1) to explore the water quality parameters at the monitoring points of the Marateca reservoir that may explain the event; (2) to validate optical water quality parameters with the monitoring points data; and (3) to model the reservoir water characteristics regarding its deepness, trophic state, and turbidity. The parameters total phosphorus, total nitrogen, and chlorophyll-a were used to compute a trophic level index. The Sentinel-2 imagery was used to compute spectral indices and bands image ratio; to obtain spectral signatures for the monitoring points, and to model water characteristics. The water parameters were above the recommended values at the reservoir entry point from the Ocreza River. The reservoir trophic level was Hypereutrophic and Eutrophic. The spectral signatures confirmed a Hypereutrophic pattern in the entry point. The Marateca reservoir’s water characteristics modeling forecasted problematic zones by contamination. The methodological approach developed can be easily applied to other reservoirs and is a key support tool for decision-makers.

Shrubland and forestland covers are highly prone to fire. The Normalized Difference Vegetation In... more Shrubland and forestland covers are highly prone to fire. The Normalized Difference Vegetation Index (NDVI) has been widely used for biomass quantitative assessment. This study aims were the following: (1) to compute the NDVI annual curve for two types of land cover eucalypts and shrubland areas; (2) to collect field data in these two types of land cover to estimate aboveground biomass (AGB); and (3) to produce AGB maps for eucalypts and shrubland areas by modelling AGB with NDVI and validate them with other data sources. A study area in the central inland Portugal was considered. The Sentinel-2 MSI imagery for the year of 2022 and 2023 were used to compute the NDVI. The NDVI annual curve for 2022 showed a minimum observed between July and August, in accordance with the climatological data, and allowed differentiating eucalypts from shrubland areas. Spectral signatures also confirmed this differentiation. The fitted linear models for AGB prediction using the NDVI imagery showed good...

Geosciences

Continuous monitoring of water resources is essential for ensuring sustainable urban water supply... more Continuous monitoring of water resources is essential for ensuring sustainable urban water supply. Remote sensing techniques have proven to be valuable in monitoring certain qualitative parameters of water with optical characteristics. This survey was conducted in the Marateca reservoir located in central inland Portugal, after a major event that killed a considerable number of fish. The objectives of the study were as follows: (1) to define a pollution spectral signature specific to the Marateca reservoir that could shed light on the event; (2) to validate the spectral water’s quality characteristics using the data collected in five gauging points; and (3) to model the characteristics of the reservoir water, including its depth, trophic state, and turbidity. The parameters considered for analysis were total phosphorus, total nitrogen, and chlorophyll-a, which were used to calculate a trophic level index. Sentinel-2 imagery was employed to calculate spectral indices and image ratios...

Forests

Sistemas de Informação Geográfica (SIG/GIS) : planeamento do solo e gestão ambiental

eLIES2018. VIIº Encontro de Instituições e Unidades de eLearning do Ensino Superior- Sessão Poste... more eLIES2018. VIIº Encontro de Instituições e Unidades de eLearning do Ensino Superior- Sessão Posters/Networking, Castelo Branco: Instituto Politécnico de Castelo Branco, co-organização do LE@D, Universidade Aberta (UID 4372/FCT), Instituto Politécnico de Castelo Branco, Universidade do Algarve.Esta comunicação apresenta os cursos de pós-graduação em parceria entre o Instituto Politécnico de Castelo Branco e a Universidade Aberta: a pós-graduação sobre proteção civil e a pós-graduação sobre sistemas de informação geográfica aplicada aos recursos agroflorestais e ambientais.info:eu-repo/semantics/publishedVersio

There are various methodologies for defining soil uses to promote sustainable utilization of rura... more There are various methodologies for defining soil uses to promote sustainable utilization of rural land. Many of these methods rely on decision support systems based on multicriteria spatial analysis. In this study, a two-step spatial approach was performed to produce forest species suitability maps. The objectives of the study were: (1) to produce bioclimatic indices maps using a geostatistical approach based on climate data; (2) to produce biogeophysical suitability maps for the main Portuguese forest species by multicriteria spatial analysis using the analytic hierarchy process (AHP) integrating three factors (terrain slope, soil diagnostic features and bioclimatic indices); and (3) to conduct a comparative analysis of the current forest species area distributions to these species biogeophysical suitability areas. With these objectives, the Centro region of Portugal was used as the study area. Our methodological approach allowed us to assess the biogeophysical suitability of Maritime pine, Eucalyptus, Cork oak and Holm oak in the Centro region of Portugal. The findings in this study emphasize the potential that the Centro region of Portugal has for expanding the spread of native oaks as recommended by the National Strategy for Forests to respond to climate changes, improve landscape biodiversity and mitigate fire hazards. The species biogeophysical suitability maps may be important tools for decision support in landscape planning to define species' priority afforestation areas. From an instrumental point of view, the use of this methodology may interest stakeholders and others with roles in planning and land management. Further investigation is needed to integrate the impact of climate change in forest species spatial modeling to assist in supporting future national strategies for forests.

Floresta e Ambiente, 2019

This paper presents a GIS methodological approach for mapping forest landscape multifunctionality... more This paper presents a GIS methodological approach for mapping forest landscape multifunctionality. The aims of the present study were: (1) to integrate and prioritize production and protection functions by multicriteria spatial analysis using the Analytic Hierarchy Process (AHP); and (2) to produce a multifunctionality map (e.g., production, protection, conservation and recreation) for a forest management unit. For this, a study area in inner Portugal occupied by forest and with an important protection area was selected. Based on maps for functions identified in the study area, it was possible to improve the scenic value and the biodiversity of the landscape to mitigate fire hazard and to diversify goods and services. The developed methodology is a key tool for producing maps for decision making support in integrated landscape planning and forest management.

Forests, 2019

Research Highlights: This study bridges a gap of knowledge about the maximum sizedensity trajecto... more Research Highlights: This study bridges a gap of knowledge about the maximum sizedensity trajectory for juvenile stands of maritime pine. The continuity of the trajectory along the development stages to maturity is assured with a straightforward approach providing support to determine optimum density along all the revolution periods for the species. Background and Objectives: Forest fire is a significant threat to forests in the Mediterranean regions, but also a natural disturbance that plays a vital role in the perpetuation of forest stands. In recent decades, there has been an increase of burnt area in maritime forests in Portugal, followed by an increased interest in managing the natural and usually abundant regeneration occurring after the fires. The gap in the knowledge of growth dynamics for juvenile stages, for these forest systems, currently constrains their correct management, for forest planning, particularly in determining the optimal densities. The study aims to identify the maximum attainable density trajectory at the early stages of development of the species that could support a non-empirical definition of silvicultural prescriptions and thinning decisions, along the revolution. Materials and Methods: A representative data set collected in stands regenerated after fire supports the analysis of the maximum size-density trajectory for the species. Results: The maximum size-density trajectory for the juvenile stands deviates from the expected trajectory defined in the self-thinning line published for the species. Significant deviation occurs at the lower end of the line, indicating the need for a reevaluation of the existing self-thinning line. We propose a new self-thinning model for the species that explicitly considers the behavior of size-density for juvenile stands. The new model assures a logical continuity for the trajectory from the young stages of development to maturity. Conclusions: The proposed model based on the maximum attainable size-density trajectory provides ecological-based support to define silvicultural guidelines for management of the species.

Forest Ecology and Management, 2019

Eucalyptus and maritime pine forests provide most of the wood harvested in Portugal. Due mainly t... more Eucalyptus and maritime pine forests provide most of the wood harvested in Portugal. Due mainly to forest fires maritime pine forest has been converted to eucalyptus plantations. In the central inland of Portugal these species are well represented, and their productivities are quite the same. The objectives of the study were: (1) to assess average wood volume, biomass production and carbon content of eucalyptus plantations and naturally regenerated maritime pine stands; (2) to evaluate biomass nutrients concentration of eucalyptus sprouts selection and maritime pine non-commercial thinning; (3) to analyse these forests cover change in relation to the annual burnt areas; and (4) to produce the species ecological envelope maps to foresee future environmental impacts of these forests current distribution. Simulation models were used to assess wood volume, biomass production and carbon content. Field data was collected to evaluate biomass nutrients concentration and to validated simulated data. Forest inventory data and forest cover maps were used to analyse forest cover change. Biogeographical variables were used to produce species ecological envelope maps. It was found that eucalyptus plantations provide higher mean annual wood volume, biomass production and carbon content. Biomass nutrients concentration in eucalyptus sprouts selection were higher than in maritime pine non-commercial thinning, particularly in calcium and potassium. Overall eucalyptus forests area did not increase substantially but the fires in maritime pine forests gave the opportunity for eucalyptus afforestation. That has precluded the opportunity for introducing native broadleaves to respond to climate changes, improve landscape biodiversity and mitigate fire hazard. Implementing good management practices to prevent losses of soil fertility by nutrients exhaustion, organic matter depletion or erosion were found more relevant in eucalyptus plantations than in naturally maritime pine forest. Species ecological envelope maps and production simulation models are key tools for supporting decision in afforestation planning.

Forests, 2020

Species ecological envelope maps were obtained for the two main Portuguese wood-production specie... more Species ecological envelope maps were obtained for the two main Portuguese
wood-production species (Eucalyptus globulus Labill. and Pinus pinaster Aiton) and projected future
climate change scenarios. A machine learning approach was used to understand the most influential
environmental variables that may explain current species distribution and productivity. Background
and Objectives: The aims of the study were: (1) to map species potential suitability areas using
ecological envelopes in the present and to project them in the future under climate change scenarios;
(2) to map species current distributions; (3) to map species current productivity; and (4) to explore the
most influential environmental variables on species current distribution and productivity. Materials
and Methods: Climate, elevation data, and soil data sets were used to obtain present and future species
ecological envelopes under two climate change scenarios. The ocial land cover maps were used
to map species distributions. Forest inventory data were used to map the species productivity by
geostatistical techniques. A Bayesian machine learning approach, supported by species distributions
and productivity data, was used to explore the most influential environmental variables on species
distribution and productivity and to validate species ecological envelopes. Results: The species
ecological envelope methodology was found to be robust. Species’ ecological envelopes showed
a high potential for both species’ a orestation. In the future, a decrease in the country’s area
potentiality was forecasted for both species. The distribution of maritime pine was found to be mainly
determined by precipitation-related variables, but the elevation and temperature-related variables
were very important to di erentiate species productivity. For eucalypts, species distribution was
mainly explained by temperature-related variables, as well as the species productivity. Conclusions:
These findings are key to support recommendations for future a orestation and will bring value to
policy-makers and environmental authorities in policy formulation under climate change scenarios.

Forests, 2021

Research Highlights: Modelling species’ distribution and productivity is key to support integrate... more Research Highlights: Modelling species’ distribution and productivity is key to support
integrated landscape planning, species’ afforestation, and sustainable forest management. Background
and Objectives: Maritime pine (Pinus pinaster Aiton) forests in Portugal were lately affected
by wildfires and measures to overcome this situation are needed. The aims of this study were: (1)
to model species’ spatial distribution and productivity using a machine learning (ML) regression
approach to produce current species’ distribution and productivity maps; (2) to model the species’
spatial productivity using a stochastic sequential simulation approach to produce the species’ current
productivity map; (3) to produce the species’ potential distribution map, by using a ML classification
approach to define species’ ecological envelope thresholds; and (4) to identify present and future
key factors for the species’ afforestation and management. Materials and Methods: Spatial land
cover/land use data, inventory, and environmental data (climate, topography, and soil) were used in
a coupled ML regression and stochastic sequential simulation approaches to model species’ current
and potential distributions and productivity. Results: Maritime pine spatial distribution modelling
by the ML approach provided 69% fitting efficiency, while species productivity modelling achieved
only 43%. The species’ potential area covered 60% of the country’s area, where 78% of the species’
forest inventory plots (1995) were found. The change in the Maritime pine stands’ age structure
observed in the last decades is causing the species’ recovery by natural regeneration to be at risk.
Conclusions: The maps produced allow for best site identification for species afforestation, wood
production regulation support, landscape planning considering species’ diversity, and fire hazard
mitigation. These maps were obtained by modelling using environmental covariates, such

Forests, 2023

To date, a variety of species potential distribution mapping approaches have been used, and the a... more To date, a variety of species potential distribution mapping approaches have been used, and
the agreement in maps produced with different methodological approaches should be assessed. The
aims of this study were: (1) to model Maritime pine potential distributions for the present and for the
future under two climate change scenarios using the machine learning Maximum Entropy algorithm
(MaxEnt); (2) to update the species ecological envelope maps using the same environmental data set
and climate change scenarios; and (3) to perform an agreement analysis for the species distribution
maps produced with both methodological approaches. The species distribution maps produced by
each of the methodological approaches under study were reclassified into presence–absence binary
maps of species to perform the agreement analysis. The results showed that the MaxEnt-predicted
map for the present matched well the species’ current distribution, but the species ecological envelope
map, also for the present, was closer to the species’ empiric potential distribution. Climate change
impacts on the species’ future distributions maps using the MaxEnt were moderate, but areas were
relocated. The 47.3% suitability area (regular-medium-high), in the present, increased in future climate
change scenarios to 48.7%–48.3%. Conversely, the impacts in species ecological envelopes maps were
higher and with greater future losses than the latter. The 76.5% suitability area (regular-favourableoptimum),
in the present, decreased in future climate change scenarios to 58.2%–51.6%. The two
approaches combination resulted in a 44% concordance for the species occupancy in the present,
decreasing around 30%–35% in the future under the climate change scenarios. Both methodologies
proved to be complementary to set species’ best suitability areas, which are key as support decision
tools for planning afforestation and forest management to attain fire-resilient landscapes, enhanced
forest ecosystems biodiversity, functionality and productivity.

Sustainability, 2022

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

Os espaços verdes urbanos (EVU) são componentes indispensáveis na qualidade ambiental urbana refl... more Os espaços verdes urbanos (EVU) são componentes indispensáveis na qualidade ambiental urbana refletindo-se na qualidade de vida dos cidadãos. As árvores encontram-se integradas de diversas formas nos EVU. Foi objetivo deste estudo analisar os EVU da cidade de Castelo Branco e avaliar a diversidade e representatividade das espécies arbóreas da sua floresta urbana. Assim, realizou-se uma síntese do inventário de 2002 e do cadastro arbóreo urbano de 2007, 2011, 2012 e 2013. Em 2002 foram inventariados 1415 exemplares em que as três espécies mais representativas foram o lodão-bastardo (Celtis australis L.), a olaia (Cersis siliquastrum L.) e o bordo-negundo (Acer negundo L.). Da análise dos dados do cadastro arbóreo de 2007 observou-se nas zonas antigas da cidade que o arvoredo apresenta um estado fitossanitário preocupante. Tal pode ser imputado à prática continuada de podas camarárias que debilitaram as árvores e as tornaram vulneráveis ao ataque de agentes patogénicos.cidade, problem...

Comunicação da qual só está disponível o resumo.Os espaços florestais, pela diversidade de funçõe... more Comunicação da qual só está disponível o resumo.Os espaços florestais, pela diversidade de funções de uso múltiplo que desempenham, devem ser encarados como fontes de serviços ecológicos, não só pela vertente produtiva e económica mas também pela conservação da biodiversidade, pela salvaguarda e recriação de paisagens, e pelo recreio e qualidade ambiental. O objetivo do estudo consistiu no desenvolvimento de uma metodologia de análise espacial com recurso à análise espacial multicritério em ambiente SIG para a definição da multifuncionalidade dos espaços florestais. A área de estudo considerada foi uma freguesia localizada no centro interior de Portugal. Para a abordagem multifuncional consideram-se as seguintes cinco funções: 1) produção; 2) proteção; 3) conservação de habitats, de espécies da fauna e da flora e de geomonumentos; 4) silvopastorícia, caça e pesca nas águas interiores; e 5) recreio, enquadramento e estética da paisagem. Produziram-se as cartas relativas à aptidão flo...

The purpose of this research was to analyze the methods used for implementation of thinnings in t... more The purpose of this research was to analyze the methods used for implementation of thinnings in three models developed to manage maritime pine stands in Portugal: (1) Pbirrol, an individual tree model that can be applied to uneven-aged stands, (2) Pinaster, an individual tree model to be used in even-aged stands, and (3) ModisPinaster, a diameter distribution model to be used in even-aged or uneven-aged stands. In these models, the decision of which trees are thinned is based on a probability function that can be associated to a cut-off or a density variable (e. g., Wilson’s factor, residual basal area, SDI). To assess the suitability of how thinnings are implemented in these models, two analyses were made: (1) even-aged models, Pinaster and ModisPinaster, were used to simulate the thinning practice of several plots of a thinning trial and stand variables estimates after thinning were compared with the measured values, and (2) forest inventory plots were used as a starting point to ...

Geosciences

Forests

Sistemas de Informação Geográfica (SIG/GIS) : planeamento do solo e gestão ambiental

Floresta e Ambiente, 2019

Forests, 2019

Forest Ecology and Management, 2019

Forests, 2020

Forests, 2021

Forests, 2023

Sustainability, 2022

É consensual que a escolha dos usos mais adequados às aptidões edafo-climáticas, complementada co... more É consensual que a escolha dos usos mais adequados às aptidões edafo-climáticas, complementada com critérios socioeconómicos, promove uma utilização sustentável dos espaços rurais. Existem, no entanto, diferentes metodologias utilizadas para a definição da capacidade e potencialidade do solo para a implementação de usos agroflorestais ou para a manutenção de ecossistemas naturais e seminaturais, nomeadamente culturas agrícolas, povoamentos florestais, territórios agro-silvo-pastoris e áreas prioritárias para a conservação da natureza. Muitas dessas metodologias recorrem a sistemas de apoio à decisão, baseados na análise espacial multicritério. Neste estudo pretendeu-se determinar os diferentes níveis de aptidão para as espécies florestais mais representativas da região centro de Portugal. Para o efeito recorreu-se a um conjunto de variáveis climáticas, edáficas e topográficas, tendo como base um modelo digital do terreno, cartografia de solos e cartografia fitossociológica e biogeográfica. Paralelamente, foram recolhidos dados das normais climatológicas de várias estações meteorológicas para o cálculo de índices bioclimáticos. Foi, ainda, utilizada uma abordagem estocástica, na estimativa dos valores dos índices bioclimáticos ensaiados, e discutidos os resultados no contexto da incerteza espacial associada. Por fim, a avaliação da aptidão das espécies florestais consideradas foi efetuada com recurso ao método de análise espacial multicritério Analytic Hierarchy Process (AHP) metodologia que permite a exploração da aptidão natural do território, contribuindo para uma reflexão sobre a adequação das ocupações atuais e futuras face à capacidade de carga do meio. Do ponto de vista instrumental, a exploração da metodologia pode assumir um interesse como auxiliar para os agentes da administração pública com funções na área do planeamento e gestão do território.

Este trabalho foi desenvolvido no âmbito do Projecto Final do Mestrado em SIG. Consistiu no estud... more Este trabalho foi desenvolvido no âmbito do Projecto Final do Mestrado em SIG. Consistiu no estudo da evolução da paisagem a partir de cartas de coberto/uso do solo obtidas por detecção remota, num período de 17 anos (1990-2007), na região Interior Centro do país (Beira Interior Sul e Pinhal Interior Sul), bem como a influência da dinâmica das unidades de paisagem sobre as aves nidificantes dessa região, utilizando softwares específicos. Constituíu-se como objectivo deste trabalho, analisar a dinâmica temporal da paisagem na referida área e verificar a sua correlação com a dinâmica populacional da avifauna nidificante, pressupondo-se que tenha ocorrido alteração nessa mesma região. Propõe-se com este estudo verificar a hipótese de haver correlação entre a composição e estrutura da paisagem com a riqueza de espécies nidificantes. Na metodologia, foram usadas métricas de paisagem para quantificar a paisagem da área de estudo em duas datas distintas (1990 e 2006) a partir de informação do CORINE Land Cover 1990 e CORINE Land Cover 2006, bem como dos Atlas das Aves Nidificantes de 1989 e 2005, de modo a extrair a informação relativa à presença/ausência das espécies de avifauna nidificante. Paralelamente, foi feita uma harmonização das classes de ocupação de solo com os habitats caracterizantes dos grupos de espécies de aves. Finalmente, foi feita uma análise temporal da variação das unidades de paisagem e paralelamente a análise da variação do número de espécies para posterior verificação da correlação entre estas duas variáveis. Os resultados revelaram que houve fragmentação da paisagem, principalmente a nível dos sistemas florestais, ao longo dos 16 anos. Em termos de recolha de informação, a escala revelou ser um elemento fulcral na análise e comparação dos dados, visto a informação presente nos dois Atlas ter sido recolhida a diferentes escalas. Por fim, existe correlação entre a estrutura e composição que define a paisagem com a riqueza de espécies presentes, com excepção das classes relativas a florestas e tecido urbano. Em suma, os resultados demonstraram que os SIGs são muito úteis para estes processos de verificação e validação de fenómenos, como também para uma visão prospectiva dos mesmos.

by Folia Forestalia Polonica , Series A - Forestry, Waldemar Moliński, Przemysław Mania, Lech Płotkowski, Stanisław Parzych, Cristina Alegria, Cristina Canavarro, Elżbieta Popowska-Nowak, Elżbieta Pezowicz, Krzysztof Ukalski, and Łukasz Tyburski

Folia Forestalia Polonica 2016, Vol. 58 (4) - Title: The usefulness of different wood species for... more Folia Forestalia Polonica 2016, Vol. 58 (4) - Title: The usefulness of different wood species for bow manufacturing, Author(s): Waldemar Moliński, Przemysław Mania, Gabriel Tomczuk, DOI: 10.1515/ffp-2016-0021; Title: Economic optimization of the rotation age of stands, Author(s): Lech Płotkowski, Stanisław Zając, Emilia Wysocka-Fijorek, Arkadiusz Gruchała, Jarosław Piekutin, Stanisław Parzych, DOI: 10.1515/ffp-2016-0022; Title: An overview of maritime pine private non-industrial forest in the centre of Portugal: A 19-year case study, Author(s): Cristina Alegria, Maria Canavarro Teixeira, DOI: 10.1515/ffp-2016-0023; Title: The role of fungus Beauveria bassiana in reducingthe number of Pissodes castaneus (Col., Curculionidae) in young forests, Author(s): Iwona Skrzecz, Elżbieta Popowska-Nowak, Robert Wolski, Alicja Sowińska, Tomasz Jabłoński, Elżbieta Pezowicz, Dorota Tumialis, Iwona Przewłoka, DOI: 10.1515/ffp-2016-0024; Title: Root biomass of Fagus sylvatica L. stands depending on the climatic conditions, Author(s): Dorota Grygoruk, DOI: 10.1515/ffp-2016-0025; Title: Application of GGE biplot graphs in multi-environment trials on selection of forest trees, Author(s): Krzysztof Ukalski, Marcin Klisz, DOI: 10.1515/ffp-2016-0026; Title: Health condition of the Scots pine (Pinus sylvestris)in Kampinos National Park – preliminary studies, Author(s): Łukasz Tyburski, Paweł Przybylski, DOI: 10.1515/ffp-2016-0027; Title: Molecular detection of oomycetes species in water courses, Author(s): Tomasz Oszako, Katarzyna Sikora, Lassaâd Belbahri, Justyna A. Nowakowska, DOI: 10.1515/ffp-2016-0028