João Gonçalves | Universidade do Porto (original) (raw)

Papers by João Gonçalves

Remote. Sens., 2022

Migratory birds are particularly exposed to habitat changes in their breeding and non-breeding gr... more Migratory birds are particularly exposed to habitat changes in their breeding and non-breeding grounds. Remote sensing technologies offer an excellent opportunity to monitor species’ habitats from space at unprecedented spatiotemporal scales. We analyzed if remotely sensed ecosystem functioning attributes (EFAs) adequately predict the spatiotemporal variation of the Woodcock’s (Scolopax rusticola) relative abundance in southwest Europe, during autumn migration and wintering periods. We used data gathered from Woodcock monitoring through citizen science (N = 355,654 hunting trips) between 2009 and 2018. We computed a comprehensive set of EFAs on a weekly basis from three MODIS satellite products: enhanced vegetation index (EVI), tasseled cap transformation (TCT), and land surface temperature (LST). We developed generalized linear mixed models to explore the predictive power of EFAs on Woodcock’s abundance during the non-breeding season. Results showed that Woodcock abundance is corre...

Biodiversity and Conservation, 2016

Applied Vegetation Science, 2015

Plant Biosystems - An International Journal Dealing with all Aspects of Plant Biology, 2013

In this paper, lLong-term impacts of meadow abandonment scenarios on plant diversity were forecas... more In this paper, lLong-term impacts of meadow abandonment scenarios on plant diversity were forecasted for High Nature Value farmland in northern Portugal, and implications for conservation planning and agri-environmental management are addressed. Vegetation patches representative of forests, meadows and edges, on mesic and wet soils, were surveyed for vascular plant diversity. Species richness and composition were compared across vegetation types, and additive partitioning was used to quantify hierarchic components of species richness. The implications of total and partial meadow abandonment were simulated according to landscape outcomes predicted for each scenario, and confirmed with a Monte-Carlo resampling. Forests hosted the highest numbers of species, as well as of exclusive species. Nonetheless, from the total pool (213), 21.6% were exclusive to meadows. Vegetation types generally shared small proportions of their species pools. With total meadow abandonment, a drastic decrease in total species richness (41.1%) and in endemic species richness (loss of 20.8%) was forecasted. However, only 12.3% of all species were forecasted to disappear under scenarios of partial abandonment. Landscape-level plant diversity can, therefore, be maintained by promoting farmland mosaics, even if the loss of scattered meadows in favour of native forests could be acceptable. Agri-environmental schemes should thus prioritize the maintenance of landscape heterogeneity.

Journal of Environmental Management, 2013

Biological Invasions, 2011

Abstract Protecting native biodiversity against alien invasive species requires powerful methods ... more Abstract Protecting native biodiversity against alien invasive species requires powerful methods to anticipate these invasions and to protect native species assumed to be at risk. Here, we describe how species distribution models (SDMs) can be used to identify areas predicted as both suitable for rare native species and highly susceptible to invasion by alien species, at present and under future climate and land-use scenarios. To assess the condition and dynamics of such conflicts, we developed a combined predictive modelling ( ...

Remote Sensing, 2021

Sea-level rise is a problem increasingly affecting coastal areas worldwide. The existence of Free... more Sea-level rise is a problem increasingly affecting coastal areas worldwide. The existence of Free and Open-Source Models to estimate the sea-level impact can contribute to better coastal man-agement. This study aims to develop and to validate two different models to predict the sea-level rise impact supported by Google Earth Engine (GEE) – a cloud-based platform for planetary-scale environmental data analysis. The first model is a Bathtub Model based on the uncertainty of projections of the Sea-level Rise Impact Module of TerrSet - Geospatial Monitoring and Modeling System software. The validation process performed in the Rio Grande do Sul coastal plain (S Brazil) resulted in correlations from 0.75 to 1.00. The second model uses Bruun Rule formula implemented in GEE and is capable to determine the coastline retreat of a profile through the creation of a simple vector line from topo-bathymetric data. The model shows a very high cor-relation (0.97) with a classical Bruun Rule study pe...

Remote Sensing

Wildfire disturbances can cause modifications in different dimensions of ecosystem functioning, i... more Wildfire disturbances can cause modifications in different dimensions of ecosystem functioning, i.e., the flows of matter and energy. There is an increasing need for methods to assess such changes, as functional approaches offer advantages over those focused solely on structural or compositional attributes. In this regard, remote sensing can support indicators for estimating a wide variety of effects of fire on ecosystem functioning, beyond burn severity assessment. These indicators can be described using intra-annual metrics of quantity, seasonality, and timing, called Ecosystem Functioning Attributes (EFAs). Here, we propose a satellite-based framework to evaluate the impacts, at short to medium term (i.e., from the year of fire to the second year after), of wildfires on four dimensions of ecosystem functioning: (i) primary productivity, (ii) vegetation water content, (iii) albedo, and (iv) sensible heat. We illustrated our approach by comparing inter-annual anomalies in satellite...

The spread of invasive alien species promotes ecosystem structure and functioning changes, with d... more The spread of invasive alien species promotes ecosystem structure and functioning changes, with detrimental effects on native biodiversity and ecosystem services, raising challenges for local management authorities. Predictions of invasion dynamics derived from modeling tools are often spatially coarse and therefore unsuitable for guiding local management. Accurate information on the occurrence of invasive plants and on the main factors that promote their spread is critical to define successful control strategies. For addressing this challenge, we developed a dual framework combining satellite image classification with predictive ecological modeling. By combining data from georeferenced invaded areas with multispectral imagery with 10-meter resolution from Sentinel-2 satellites, a map of areas invaded by the woody invasive Acacia longifolia in a municipality of northern Portugal was devised. Classifier fusion techniques were implemented through which eight statistical and machine-le...

ISPRS International Journal of Geo-Information

The Iberian Peninsula hosts a high diversity of oak species, being a hot-spot for the conservatio... more The Iberian Peninsula hosts a high diversity of oak species, being a hot-spot for the conservation of European White Oaks (Quercus) due to their environmental heterogeneity and its critical role as a phylogeographic refugium. Identifying and ranking the drivers that shape the distribution of White Oaks in Iberia requires that environmental variables operating at distinct scales are considered. These include climate, but also ecosystem functioning attributes (EFAs) related to energy–matter exchanges that characterize land cover types under various environmental settings, at finer scales. Here, we used satellite-based EFAs and climate variables in species distribution models (SDMs) to assess how variables related to ecosystem functioning improve our understanding of current distributions and the identification of suitable areas for White Oak species in Iberia. We developed consensus ensemble SDMs targeting a set of thirteen oaks, including both narrow endemic and widespread taxa. Mode...

Landscape and Urban Planning

Ongoing declines in biodiversity caused by global environmental changes call for adaptive conserv... more Ongoing declines in biodiversity caused by global environmental changes call for adaptive conservation management, including the assessment of habitat suitability spatiotemporal dynamics potentially affecting species persistence. Remote sensing (RS) provides a wide-range of satellite-based environmental variables that can be fed into species distribution models (SDMs) to investigate species-environment relations and forecast responses to change. We address the spatiotemporal dynamics of species' habitat suitability at the landscape level by combining multi-temporal RS data with SDMs for analysing inter-annual habitat suitability dynamics. We implemented this framework with a vulnerable plant species (Veronica micrantha), by combining SDMs with a time-series of RS-based metrics of vegetation functioning related to primary productivity, seasonality, phenology and actual evapotranspiration. Besides RS variables, predictors related to landscape structure, soils and wildfires were ranked and combined through multi-model

Environmental changes are driving rapid geographic shifts of suitable environmental conditions fo... more Environmental changes are driving rapid geographic shifts of suitable environmental conditions for species. These might survive by tracking those shifts, however successful responses will depend on the spatial distribution of suitable habitats (current and future) and on their connectivity. Most herptiles (i.e., amphibians and reptiles) have low dispersal abilities, and therefore herptiles are among the most vulnerable groups to environmental changes. Here we assessed the vulnerability of herptile species to future climate and land use changes in fragmented landscapes. We developed and tested a methodological approach combining the strengths of Species Distribution Models (SDMs) and of functional connectivity analysis. First, using SDMs we forecasted current and future distributions of potential suitable areas as well as range dynamics for four herptile species in Portugal. SDM forecasts for 2050 were obtained under two contrasting emission scenarios, translated into moderate (low-emissions scenario) or large (high-emissions scenario) changes in climate and land use conditions. Then, we calculated and analysed functional connectivity from areas projected to lose environmental suitability towards areas keeping suitable conditions. Landscape matrix resistance and barrier effects of the national motorway network were incorporated as the main sources of fragmentation. Potential suitable area was projected to decrease under future conditions for most test species, with the high-emissions scenario amplifying the losses or gains. Spatiotemporal patterns of connectivity between potentially suitable areas signalled the most important locations for maintaining linkages and migration corridors, as well as potential conflicts due to overlaps with the current motorway network. By integrating SDM projections with functional connectivity analysis, we were able to assess and map the vulnerability of distinct herptile species to isolation or extinction under environmental change scenarios. Our framework provides valuable information, with fairly low data requirements, for optimizing biodiversity management and mitigation efforts, aiming to reduce the complex and often synergistic negative impacts of multiple environmental change drivers. Implications for conservation planning and management are discussed from a global change adaptation perspective.

Question Can very high-resolution colour orthophotography and digital surface models (DSMs) from... more Question

Can very high-resolution colour orthophotography and digital surface models (DSMs) from an unmanned aerial vehicle (UAV) be effectively used for assessment of habitat extent and condition in fine-scale disturbance-dependent mosaics?
Location

Serra de Arga mountain range, a Natura 2000 protected site in the NW region of Portugal where drastic changes in pastoral activities have occurred over recent decades.
Methods

An UAV platform was used to collect very high-resolution (6 cm) images and to produce a DSM (10 cm). From these data, several features were extracted related to colour, band ratios, as well as texture features calculated from colour imagery and surface elevation. Based on a systematic sampling design, field data were collected for both training and validation of a supervised classifier. Extracted features and ground truth training data were combined to calibrate a pixel-based Random forest classifier, with the purpose of devising a habitat map for the entire study area. Map validation was performed to assess classification accuracy, and feature importance metrics were calculated.

Results

Validation results revealed good mean overall accuracy (0.89), with some performance decrease in situations of high interspersion of habitat types. The priority habitat type 6230* (Nardus grasslands), defining the vegetation matrix of the test site, obtained 0.96 and 0.91, considering, respectively, producer and user accuracy. In turn, priority habitat type 4020* (Atlantic wet heathlands) recorded 0.68 and 0.77. The obtained habitat map allowed measurement of the extent, description of the spatial arrangement and provided an indication of the conservation condition of target habitat types. Test results regarding the discrimination ability of different features highlighted the importance of surface elevation textures derived from the DSM, followed by band ratios textures and other more complex texture features calculated from colour imagery.

Conclusions

Overall, the developed methodology showed promising results for assessing the extent and condition of habitats of high conservation priority in fine-scale, dynamic vegetation mosaics. Future advances in the use of UAV platforms may play an important role in monitoring protected sites and fulfil legal reporting obligations of EU member states, while reducing the costs associated with intensive in-field assessments.

Journal of Environmental Management, 2013

We describe a novel dissimilarity framework to analyze spatial patterns of species diversity and ... more We describe a novel dissimilarity framework to analyze spatial patterns of species diversity and illustrate it with alien plant invasions in Northern Portugal. We used this framework to test the hypothesis that patterns of alien invasive plant species richness and composition are differently affected by differences in climate, land use and landscape connectivity (i.e. Geographic distance as a proxy and vectorial objects that facilitate dispersal such as roads and rivers) between pairs of localities at the regional scale. We further evaluated possible effects of plant life strategies (Grime's C-S-R) and residence time. Each locality consisted of a 1 km2 landscape mosaic in which all alien invasive species were recorded by visiting all habitat types.

Multi-model inference revealed that dissimilarity in species richness is more influenced by environmental distance (particularly climate), whereas geographic distance (proxies for dispersal limitations) is more important to explain dissimilarity in species composition, with a prevailing role for ecotones and roads. However, only minor differences were found in the responses of the three C-S-R strategies. Some effect of residence time was found, but only for dissimilarity in species richness. Our results also indicated that environmental conditions (e.g. climate conditions) limit the number of alien species invading a given site, but that the presence of dispersal corridors determines the paths of invasion and therefore the pool of species reaching each site. As geographic distances (e.g. ecotones and roads) tend to explain invasion at our regional scale highlights the need to consider the management of alien invasions in the context of integrated landscape planning. Alien species management should include (but not be limited to) the mitigation of dispersal pathways along linear infrastructures. Our results therefore highlight potentially useful applications of the novel multimodel framework to the anticipation and management of plant invasions.

Remote. Sens., 2022

Biodiversity and Conservation, 2016

Applied Vegetation Science, 2015

Plant Biosystems - An International Journal Dealing with all Aspects of Plant Biology, 2013

Journal of Environmental Management, 2013

Biological Invasions, 2011

Remote Sensing, 2021

Remote Sensing

ISPRS International Journal of Geo-Information

Landscape and Urban Planning

Question Can very high-resolution colour orthophotography and digital surface models (DSMs) from... more Question

Serra de Arga mountain range, a Natura 2000 protected site in the NW region of Portugal where drastic changes in pastoral activities have occurred over recent decades.
Methods

Results

Conclusions

Journal of Environmental Management, 2013

As florestas são repositórios de valores naturais e culturais de elevada importância para a socie... more As florestas são repositórios de valores naturais e culturais de elevada importância para a sociedade. Pelo seu papel na conservação da biodiversidade, no desenvolvimento económico e na construção identitária das sociedades que delas usufruíram e usufruem, as florestas constituíram-se como ecossistemas de especial relevo nas dinâmicas sociais e ambientais ao longo dos tempos. As florestas são ecossistemas complexos, com estrutura e funcionamento muito diversos e dependentes de inúmeros fatores. Neste contexto, o seu estudo contribuirá de forma decisiva para a sua preservação e valorização, no quadro alargado da gestão sustentável dos recursos naturais e da partilha equilibrada dos benefícios gerados pelos ecossistemas.
Tendo a Assembleia-Geral das Nações Unidas declarado 2011 como Ano Internacional das Florestas, subordinado ao lema “Florestas para todos”, o consórcio InBio (Rede de Investigação em Biodiversidade e Biologia Evolutiva) reconheceu a relevância e pertinência da efeméride e assumiu com naturalidade o seu desejo de participar nas comemorações. Este e-book surge precisamente no âmbito dessa associação do InBio à celebração do Ano Internacional das Florestas. De facto, esta iniciativa relaciona-se de forma harmoniosa com o percurso científico e de participação cívica das instituições que compõem o InBio, não só na forma de inúmeros trabalhos de índole científica e académica, mas também considerando as frequentes ações de divulgação e sensibilização para o público e ainda o estabelecimento de planos estratégicos visando a preservação e o melhor conhecimento da biodiversidade e dos sistemas ecológicos. Os textos compilados no presente e-book refletem uma parte da diversidade de abordagens seguidas na investigação ecológica e na sua aplicação à gestão e conservação das florestas nacionais.
O lema “Florestas para todos”, pleno de atualidade e pertinência, espelha a necessidade de refletir acerca do papel do Homem na evolução dos ecossistemas florestais, na sua preservação, gestão e valorização. Ao mesmo tempo, este lema assinala a complexidade do estudo das florestas e a necessidade de garantir uma visão plural, diacrónica e multidisciplinar. Esta obra pretende ir ao encontro desta necessidade, juntando contribuições de especialistas de distintas disciplinas científicas, tais como a Ecologia, a Engenharia Florestal e a Arqueologia. Partindo de diferentes perspetivas, estes especialistas têm desenvolvido investigação fundamental e aplicada sobre o tema deste ano internacional e, em particular, sobre as florestas nacionais e regionais. Tais esforços de investigação encontram-se espelhados nesta obra, daí resultando a convicção de que o resultado é uma visão renovada e atualizada do que é a Floresta hoje, como evoluiu até aos nossos dias, quais são as principais ameaças que sobre ela incidem e quais são os principais desafios para a sua gestão futura.