Please use this identifier to cite or link to this item: http://hdl.handle.net/10316/29520
Title: Resilience to land use induced impacts
Authors: Teixeira, Zara Fani Gonçalves 
Orientador: Marques, João Carlos
Keywords: Gestão integrada de bacia hidrográfica; Directiva-Quadro da Água; DPSIR; Indicadores ambientais; Qualidade da água; Pressões antrópicas; Ocupação do solo; Sistemas costeiros; Integrated river basin management; Water Framework Directive; Water quality; Anthropogenic pressures; Land cover; Coastal systems; Environmental indicators
Issue Date: 23-Feb-2016
Citation: TEIXEIRA, Zara Fani Gonçalves - Resilience to land use induced impacts. Coimbra : [s.n.], 2016. Tese de doutoramento. Disponível na WWW: http://hdl.handle.net/10316/29520
Abstract: A Directiva-Quadro da Água reforça o papel dos usos do solo na avaliação da qualidade da água, mas a utilização de dados de ocupação do solo, no que respeita a águas de superfície, restringe-se à estimativa dos padrões de uso do solo para a identificação de pressões provenientes de fontes de poluição difusas. O principal objetivo deste estudo é identificar especificidades da ocupação dos usos do solo na avaliação das mudanças de estado (Capítulo I), pressões (Capítulo I e II) e forças motrizes (Capítulo III e IV) da qualidade das águas de superfície. Para o efeito, usamos dados da bacia hidrográfica do Rio Mondego, uma bacia costeira localizada em Portugal, onde as mudanças socioeconómicas têm sido observadas desde a década de 1990 e que resultaram na perda de representatividade do setor agrícola e ganho do setor da construção. Apesar das mudanças, a agricultura mantém-se como uma fonte de pressão sobre as águas de superfície que, associada a modificações hidromorfológicas, causaram um declínio da qualidade ecológica do estuário do Mondego. Em 1998, a implementação de medidas de mitigação permitiu a recuperação do sistema, mas a monitorização identificou elevadas concentrações de nutrientes que pediam uma avaliação da sua proveniência. Por esta razão, a bacia do Rio Mondego, emerge como um caso de estudo com as condições necessárias para identificar aplicações mais amplas de dados de ocupação do solo no âmbito da identificação de forças motrizes e pressões sobre a qualidade da água. O Capítulo I estabelece a linha de base para este trabalho através da aplicação de indicadores de nutrientes e de substâncias-consumidoras-de-oxigénio para analisar a evolução das concentrações de amónia, nitrato e fosfato no estuário do Mondego entre os períodos 2003-2007 e 2012-2013 (ANOVA no software R); para analisar as diferenças entre as concentrações médias anuais de nutrientes nos rios tributários em 2012-2013 e as concentrações médias anuais encontradas em rios europeus em três períodos diferentes (1992, 2000, 2012); e para avaliar as diferenças na variabilidade das concentrações de nutrientes no estuário e nos tributários em 2012-2013 (ANOVA em software R). Adicionalmente, o Capítulo I avalia a dependência das concentrações de nutrientes estuarinas das entradas de água doce provenientes dos tributários, em dois períodos distintos. Procurou-se a relação linear entre as concentrações de nutrientes e a salinidade, a precipitação e a temperatura (regressão linear no software R). Os resultados revelam diferenças entre os intervalos de tempo e mostram uma dependência das concentrações de nutrientes das entradas de água doce proveniente dos rios, o que indica pressão de cargas de nutrientes sobre o estuário. No Capítulo II a pressão exercida pela descarga de nutrientes nos rios da bacia hidrográfica é avaliada utilizando dados de ocupação do solo. Analisa-se a adequação de métricas de paisagem para descrever a variabilidade espacial de nitratos em toda a bacia do rio Mondego usando dados sazonais de 2001 e 2006 (modelo linear misto - software R). Os resultados revelam que os padrões de ocupação do solo são descritores fracos da variabilidade espacial de nitratos na bacia do rio Mondego. No Capítulo III caracterizam-se as forças motrizes da qualidade da água usando como proxy os processos de mudança da paisagem. Os mapas CORINE de 1990, 2000 e 2006 são utilizados para analisar as mudanças entre oito categorias de ocupação, através de uma análise alargada de matrizes de transição. A magnitude da mudança e a consistência das transições revelam que as forças motrizes mais relevantes incluem categorias com baixa percentagem de ocupação, mas elevado efeito potencial nos processos hidrológicos. No Capítulo IV, reconhecendo que a precisão dos mapas pode influenciar a nossa percepção acerca das forças motrizes que atuam no sistema, aplica-se uma Análise de Intensidade para avaliar a adequação dos mapas CORINE como indicadores de mudanças de ocupação. Transições inconsistentes indicam erros de classificação que se poderiam propagar para outras aplicações que utilizam mapas de mudança de ocupação do solo. Analisando os resultados concluímos que ainda há espaço para o desenvolvimento de indicadores, nomeadamente indicadores de eficácia-de-políticas; que os dados de ocupação do solo como indicadores de pressão podem revelar o efeito, a longo prazo, da implementação de políticas; que a magnitude e a consistência dos processos de mudança de ocupação do solo revelam informações adicionais relativamente à avaliação das forças motrizes de transições de ocupação e que os mapas CORINE, apesar de serem dados de elevada qualidade, têm limitações de precisão facilmente identificadas através de uma Análise de Intensidade. Em relação à concentração de nutrientes, o nosso estudo sugere que são necessárias medidas de mitigação para reduzir as entradas de concentrações de fosfato para o estuário, de preferência por meio de políticas a nível europeu. The European Water Framework Directive enhances the role of land use in determining water quality of all waters, but the use of land cover data, regarding surface waters, is restricted to the estimation of land use patterns for the identification of pressures on surface waters from diffuse source pollution. The main goal of this study is to uncover specificities of land cover in the assessment of state changes (Chapter I), pressures (Chapt er I and II) and drivers (Chapter III and IV) of water quality of surface waters. For this purpose, we use data from the Mondego river basin, a coastal watershed in Portugal , where socio - economic changes observed since the 1990 s resulted in the loss of rep resentativeness from the agricultural sector and gain from the construction sector. Despite the observed changes, agriculture remained a source of pressure on surface waters which, associated with hydro - morphological modifications, caused a decline of the ecological quality of the Mondego estuary. In 1998, the implementation of mitigation measures enabled the recovery of the system but routine monitoring identified high concentrations of nutrients deserving further assessment to understand its sources. For this reason, the Mondego river basin, as a case study, provided conditions to reveal wider applications of land cover data within the assessment of drivers and pressures of water quality. Chapter I establishes the baseline for our research applying indicat ors of nutrients and oxygen - consuming - substances to analyze progress in the concentrations of ammonia, nitrate and phosphate in the Mondego estuary from a former period (2003 - 2007) to a recent period (2012 - 2 2013) (ANOVA in R software); to analyze difference s between the annual mean concentrations of nutrients in the tributary rivers in 2012 - 2013 and the average annual mean concentrations found in European rivers in three different periods (1992, 2000, 2012); and to evaluate differences in the variability of nutrient concentrations between the estuary and the tributaries in 2012 - 2013 (ANOVA in R software). Additionally, Chapter I evaluates the dependency of estuarine nutrient concentration s on riverine freshwater inputs in two different periods. A linear relat ionship between the nutrient concentrations and salinity, precipitation and temperature was sought (linear regression in R software). Altogether the results indicate differences between time intervals and are able to establish a dependency of nutrient conc entrations on riverine freshwater inputs, indicating pressure from nutrient loadings on the estuary. In Chapter II pressure from nutrient flushing on the river basin is evaluated using land cover data as an indicator. The suitability of landscape metrics t o describe the spatial variability of nitrate across the Mondego river basin is assessed using seasonal data from the years 2001 and 2006 (linear mixed model - R software). The results reveal that land cover patterns are weak descriptors of nitrate spatial variability in the Mondego river basin. In Chapter III driving forces of water quality are characterized using processes of landscape change as proxy. CORINE Land cover maps at 1990, 2000 and 2006 are used to analyze changes among eight categories throug h an extended analysis of transition matrices. The magnitude of change and consistency of transitions reveal that the most relevant driving forces from land transitions include categories with low percentage of occupation but high potential effect on hydro logical processes. In Chapter IV, acknowledging that the accuracy of maps may influence our perception of the main driving forces acting in the system, the Intensity Analysis approach is applied to evaluate the suitability of the CORINE land cover maps as indicators of land change. Inconsistent transitions reveal the misclassification errors that could propagate to other land cover change applications, as in the assessment of hydrological processes. Through the analysis of the results we conclude that there is still space for the development of indicators, namely policy effectiveness indicators; land cover data as indicator of pressure may reveal the effect of policies’ implementation in the long - term; the magnitude and con sistency of the processes of land change reveal additional information regarding the assessment of driving Abstract 3 forces from land transitions and that CORINE maps, though being high quality datasets, have accuracy limitations that are easily accessed through Int ensity Analysis. Regarding nutrient concentrations, our study suggests that mitigation measures, preferably through policies at the European level, are needed to reduce the inputs of phosphate concentrations into the estuary.
The European Water Framework Directive enhances the role of land use in determining water quality of all waters, but the use of land cover data, regarding surface waters, is restricted to the estimation of land use patterns for the identification of pressures on surface waters from diffuse source pollution. The main goal of this study is to uncover specificities of land cover in the assessment of state changes (Chapter I), pressures (Chapter I and II) and drivers (Chapter III and IV) of water quality of surface waters. For this purpose, we use data from the Mondego river basin, a coastal watershed in Portugal, where socio-economic changes observed since the 1990s resulted in the loss of representativeness from the agricultural sector and gain from the construction sector. Despite the observed changes, agriculture remained a source of pressure on surface waters which, associated with hydro-morphological modifications, caused a decline of the ecological quality of the Mondego estuary. In 1998, the implementation of mitigation measures enabled the recovery of the system but routine monitoring identified high concentrations of nutrients deserving further assessment to understand its sources. For this reason, the Mondego river basin, as a case study, provided conditions to reveal wider applications of land cover data within the assessment of drivers and pressures of water quality. Chapter I establishes the baseline for our research applying indicators of nutrients and oxygenconsuming-substances to analyze progress in the concentrations of ammonia, nitrate and phosphate in the Mondego estuary from a former period (2003-2007) to a recent period (2012) - 2013) (ANOVA in R software); to analyze differences between the annual mean concentrations of nutrients in the tributary rivers in 2012-2013 and the average annual mean concentrations found in European rivers in three different periods (1992, 2000, 2012); and to evaluate differences in the variability of nutrient concentrations between the estuary and the tributaries in 2012-2013 (ANOVA in R software). Additionally, Chapter I evaluates the dependency of estuarine nutrient concentrations on riverine freshwater inputs in two different periods. A linear relationship between the nutrient concentrations and salinity, precipitation and temperature was sought (linear regression in R software). Altogether the results indicate differences between time intervals and are able to establish a dependency of nutrient concentrations on riverine freshwater inputs, indicating pressure from nutrient loadings on the estuary. In Chapter II pressure from nutrient flushing on the river basin is evaluated using land cover data as an indicator. The suitability of landscape metrics to describe the spatial variability of nitrate across the Mondego river basin is assessed using seasonal data from the years 2001 and 2006 (linear mixed model - R software). The results reveal that land cover patterns are weak descriptors of nitrate spatial variability in the Mondego river basin. In Chapter III driving forces of water quality are characterized using processes of landscape change as proxy. CORINE Land cover maps at 1990, 2000 and 2006 are used to analyze changes among eight categories through an extended analysis of transition matrices. The magnitude of change and consistency of transitions reveal that the most relevant driving forces from land transitions include categories with low percentage of occupation but high potential effect on hydrological processes. In Chapter IV, acknowledging that the accuracy of maps may influence our perception of the main driving forces acting in the system, the Intensity Analysis approach is applied to evaluate the suitability of the CORINE land cover maps as indicators of land change. Inconsistent transitions reveal the misclassification errors that could propagate to other land cover change applications, as in the assessment of hydrological processes. Through the analysis of the results we conclude that there is still space for the development of indicators, namely policy effectiveness indicators; land cover data as indicator of pressure may reveal the effect of policies’ implementation in the long-term; the magnitude and consistency of the processes of land change reveal additional information regarding the assessment of driving forces from land transitions and that CORINE maps, though being high quality datasets, have accuracy limitations that are easily accessed through Intensity Analysis. Regarding nutrient concentrations, our study suggests that mitigation measures, preferably through policies at the European level, are needed to reduce the inputs of phosphate concentrations into the estuary.
Description: Tese de doutoramento em Biociência, na especialidade de Ecologia, apresentada ao Departamento de Ciências da Vida da Faculdade de Ciências e Tecnologia da Universidade de Coimbra
URI: http://hdl.handle.net/10316/29520
Rights: openAccess
Appears in Collections:FCTUC Ciências da Vida - Teses de Doutoramento

Files in This Item:
File Description SizeFormat
Resilience to land use induced impacts.pdfTese Doutoramento6.2 MBAdobe PDFView/Open
Show full item record

Page view(s) 20

506
checked on Oct 22, 2020

Download(s)

82
checked on Oct 22, 2020

Google ScholarTM

Check


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.