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- Ecohydrology in a Brazilian tropical dry forest: thinned vegetation impact on hydrological functions and ecosystem servicesPublication . Andrade, Eunice Maia; Guerreiro, Maria João Simas; Palácio, Helba Araújo Queiroz; Campos, Diego AntunesStudy region This study was developed in two paired catchments under a tropical dry climate with a tropical dry forest landcover subject to vegetation management in the Brazilian northeastern region. Water input is mostly from rainfall, concentrated in three to four months of the year and with a potential evaporation that is over twice the amount of rainfall that characterizes its hydric deficit. Study focus Interactions between hydrological functions, services and human actions to minimize environmental impacts, improve the availability of water of good quality and decrease degradation of the ecosystems; land use management effect on systems resilience, impact on surface runoff, soil loss, herbaceous and radicular biomass production, soil humidity and total organic carbon under altered vegetation cover. New hydrological insights for the region Strategies to improve ecosystem services should rely on adequate management of vegetation to reduce surface flow. This reduction contributes to higher soil moisture contents, less intense erosive processes and resulting higher stocked soil carbon. The many techniques that improve resilience and ecosystem services in tropical dry forests lack an integrated view on how ecohydrological processes may be managed to favor the system. Vegetation thinning promotes underbrush development that dissipates rainfall and surface flow kinetic energy, increasing soil moisture content and carbon fixation and reducing soil loss.
- Flood analysis with the standardized precipitation index (SPI)Publication . Guerreiro, Maria João; Lajinha, Teresa; Abreu, IsabelThe occurrence of flood spells is difficult to monitor and detect. However, there are some indices that permit to monitor hydrological and climatological conditions in river basins. The SPI (Standardized Precipitation Index) is one of those indices. Though the SPI was originally developed for drought detection and monitoring, it can also be applied to perceive wetter than normal conditions. This study pretends to characterize the relationship between the SPI and annual peak flow occurrences in the Tejo (Portugal) river basin and provide a tool for prediction of high flood risk. Results indicate that SPI satisfactorily explained the development of circumstances leading up to major peak flow events.
- Projeto Exploratório ACAMAI - automatizar o mapeamento de acessibilidades urbanas com IA / Automating city accessibility mapping using AIPublication . Dinis, Maria Alzira Pimenta; Guerreiro, Maria João; Sucena-Garcia, Sara; Silva, VítorACAMAI / Fundação para a Ciência e Tecnologia (FCT) Automatizar o Mapeamento de Acessibilidades Urbanas com IA / Automating City Accessibility Mapping using AI 2022.09218.PTDC (https://www.fct.pt/apoios/projectos/concursos/ICDT/docs/Resultados_Projetos_2022.xlsx) Investigador Responsável (IR)
- Eco-physiological characterization of the macroinverterbate communities of a very disturbed urban stream (Rio Tinto, Portugal): How they survive?Publication . Jesus, Teresa Maria Gonçalves Moreira de; Monteiro, Álvaro; Guerreiro, Maria João; Abreu, Isabel; Amado, Ana; Costa, Miguel
- Report presenting the first results of LookCrim ProjectPublication . Nunes, Laura M.; Sani, Ana Isabel; Dinis, Maria Alzira Pimenta; Gouveia, Feliz Ribeiro; Oliveira, Gisela; Guerreiro, Maria João; Freitas, Pedro; Estrada, Rui; Maia, Rui Leandro; Caridade, Sónia; Azevedo, Vanessa; Paulo, Daniela; dos Santos, Hugo; Ferreira, Inês; Gonçalves, Maria João
- Temporal variability of theft types in the historic centre of PortoPublication . Azevedo, Vanessa; Magalhães, Mariana; Paulo, Daniela; Maia, Rui Leandro; Oliveira, Gisela; Guerreiro, Maria João; Sani, Ana; Nunes, Laura M.Criminology theories imply that time is a relevant variable, especially for the prevention and intervention of criminal occurrences. Thus, the study of criminal temporal patterns has been described as being of great relevance. The present study focuses on describing and exploring the influence of temporal and seasonal variables on the occurrence of different types of theft in the Historic Centre of Porto through the analysis of official records of the Public Security Police. Significant differences were found regarding the time of day and season of occurrence, even though it is not observed for all the types of theft analysed. Overall, theft was more prevalent at night and less frequent during winter, which is congruent with previous literature and the routine activity theory. Being the first case study in Porto city, Portugal, this research may be of extreme importance for both designing prevention and intervention policies in the area, and for inspiring future research on a criminal time analysis.
- Times and spaces of crime in the Historic Centre of Porto: evidence from official dataPublication . Maia, Rui Leandro; Guerreiro, Maria João; Paulo, Daniela; Azevedo, Vanessa; Sani, Ana IsabelThe analysis of official data is a traditional strategy to study criminality in a geographic space (e.g., city, country). This work focuses on the analysis of the official statistics of crime against property at the Historic Centre of Porto, Portugal, in 2018. It addresses temporal (i.e., by period of the week, time of day) and spatial patterns (i.e., spatial analysis, typology of spaces) of crime occurrences. The database was analyzed through descriptive and inferential statistics, and by spatial density analysis. Theft was the most common type of crime, although crime types varied greatly with location, and time of the day. There were no significant differences on crime occurrences by days of the week and most crimes were reported in the afternoon. Concerning typology of spaces, most crimes occurred at linear spaces, especially robberies. Findings can be very useful for sustainable and considered urban planning, by aligning the location of material and human resources with the detection of seasonal and comparable crime patterns, enabling more efficient crime prevention in urban areas.
- Comparative statistical analysis new urban road pavement versus conventional pavement of pervious concretePublication . de Oliveira, Evailton Arantes; Guerreiro, Maria João; Abreu, Isabel; Dinis, Maria Alzira PimentaThis research proposes a variation to pervious concrete pavement, in which a mixture of cement, aggregates and water includes calcium hydroxide additive (Ca(OH)2). This new approach focuses on two main environmental functions: increased permeability of urban soil favoring a decrease of total and peak runoff and resulting reduction of flood occurrence in the cities, and CO2 absorption from the atmosphere, contributing to reduction of the negative impacts caused by the observed increased greenhouse effect in the cities. A series of 40 conventional pervious concrete pavement samples and 30 specimens of the proposed urban pavement were tested in the laboratory for permeability, density, porosity and compression resistance, and monitored for CO2 absorption. Results show that there is an environmental benefit of CO2 sequestration when adding Ca(OH)2 to pervious concrete, but there is also a decrease in its compressive strength and permeability.
- Análise de correlação entre o escoamento e o índice de precipitação padronizado spi (standardized precipitation index) na bacia hidrográfica do rio LimaPublication . Lajinha, Teresa; Guerreiro, Maria JoãoA seca é um fenómeno meteorológico com efeitos nefastos a nível social, económico e ambiental. Sendo difícil de prever, existem vários indicadores que permitem avaliar a sua severidade num determinado período de tempo. O Standardized Precipitation Índex, SPI, desenvolvido por McKee, é um desses indicadores e a sua determinação requer que se conheça unicamente a precipitação mensal durante um período mínimo de trinta anos. Neste trabalho analisa-se a relação existente entre o índice SPI mensal e o escoamento mensal em dois pares de estações (meteorológicas e hidrométricas) localizadas na bacia hidrográfica do rio Lima procurando relacionar um índice de precipitação com fenómenos extremos de seca/períodos húmidos. A drought is a meteorological phenomenon with adverse effects at the social, economic and environmental level. Being difficult to predict the phenomena, there are several indicators which evaluate the severity during a time period. The Standardized Precipitation Index (SPI) developed by McKee, is one of these indicators and only thirty years of monthly precipitation data are necessary for its evaluation. The relationship between SPI and monthly flow was analyzed at two sets of gauges (raingauge-streamflow), located at the Lima river basin, in order to relate a precipitation index to drought/humid periods.
- Enhancing ecosystem services to minimize impact of climate variability in a dry tropical forest with vertisolsPublication . Guerreiro, Maria João; Maia de Andrade, Eunice; Palácio, Helba Araújo de Queiroz; Brasil, José Bandeira; Ribeiro Filho, Jacques Carvalho RibeiroIncreased droughts and variable rainfall patterns may alter the capacity to provide ecosystem services, such as biomass production and clean water provision. The impact of these factors in a semi-arid region, especially on a dry tropical forest with Vertisols and under different land uses such as regenerated vegetation and thinned vegetation, is still unclear. This study analyzes hydrologic processes under precipitation pulses and intra-seasonal droughts, and suggests management practices for ecosystem services improvement. A local 43-year dataset showed a varying climate with a decrease in number of small events, and an increase in the number of dry days and in event rainfall intensity, in two catchments with different land use patterns and with Vertisols, a major soil order in semi-arid tropics. The onset of runoff depends on the expansive characteristics of the soil rather than land use, as dry spells promote micro-cracks that delay the runoff process. Forest thinning enhances groundcover development and is a better management practice for biomass production. This management practice shows a lower water yield when compared to a regenerated forest, supporting the decision of investing in forest regeneration in order to attend to an increasing water storage demand.