Η οδηγία της Ευρωπαϊκής Ένωσης 2000/60 για τα νερά θέτει το πλαίσιο δράσης όλων των κρατών μελών της Ευρωπαϊκής Ένωσης για σωστή διαχείριση των υδάτινων πόρων τους προκειμένου να επιτευχθεί «καλή» οικολογική ποιότητα των επιφανειακών και υπόγειων υδάτων τους μέχρι το έτος 2015 και να αποτραπεί η περαιτέρω υποβάθμισή τους, με στόχο να διασφαλισθεί η υγιής λειτουργία των υδρόβιων οικοσυστημάτων. Προκειμένου να εκτιμηθεί η οικολογική ποιότητα των υδάτων των ποταμών Πείρου-Παραπείρου και Βουραϊκού, πραγματοποιήθηκαν δειγματοληψίες και εν συνεχεία χημικές, υδρομορφολογικές και βιολογικές αναλύσεις σε έντεκα θέσεις, επιλεγμένες με συγκεκριμένα κριτήρια κατά μήκος αυτών. Συγκεκριμένα, η συλλογή των δειγμάτων πραγματοποιήθηκε και τις τέσσερις εποχές του έτους 2006, ενώ στους ποταμούς Πείρο και Παραπείρο υλοποιήθηκε μια επιπλέον δειγματοληψία κατά την άνοιξη του έτους 2007. Η υδρομορφολογική ανάλυση πραγματοποιήθηκε ακολουθώντας τη μεθοδολογία River Habitat Survey, ενώ η βιολογική ανάλυση περιελάμβανε τη συλλογή δειγμάτων βενθικών μακροασπον-δύλων σύμφωνα με τη μεθοδολογία STAR AQEM. Παράλληλα, χρησιμοποιήθηκαν τεχνικές στατιστικής ανάλυσης προκειμένου να εντοπιστούν οι σημαντικότερες περιβαλλοντικές παράμετροι που επηρεάζουν τις βιοκοινότητες των μακροασπον-δύλων. Για τον υπολογισμό της οικολογικής ποιότητας εφαρμόστηκε η μεθοδολο-γία REFCOND προκειμένου να εκτιμηθεί αυτή με βάση την επιμέρους συμβολή των χημικών, υδρομορφολογικών και βιολογικών παραμέτρων στη διαμόρφωσή της. Σύμφωνα με τα αποτελέσματα της έρευνας περισσότερο του ήμισυ του μήκους των ποταμών Πείρου-Παραπείρου και των 3/5 του μήκους του ποταμού Βουραϊκού δεν ικανοποιούν τις απαιτήσεις της οδηγίας 2000/60/ΕΕ, εκτιμώμενη η οικολογική τους ποιότητα από «φτωχή» έως «μέτρια». Για τους Πείρο και Παραπείρο, η ποιοτική υποβάθμιση αποδίδεται σε αγροτικές και κτηνοτροφικές δραστηριότητες καθώς και στην παρουσία αστικών και βιομηχανικών αποβλήτων στις κατάντη θέσεις. Η αντίστοιχη του Βουραϊκού, εν μέρει οφείλεται σε αγροκτηνοτροφικές δραστηριότη-τες αλλά κυρίως στην παρουσία σημαντικών ποσοτήτων τυροκομικών αποβλήτων. Επιπλέον, τα ευρήματα στο συγκεκριμένο ποτάμι πιστοποιούν τον καθοριστικό ρόλο της παρόχθιας βλάστησης στην απορρύπανση των υδάτων των ποταμών. Κατόπιν των ανωτέρω κρίνεται επιτακτική η ανάγκη να ληφθούν τα ενδεδειγμένα μέτρα προστασίας των νερών των ποταμών από τα παντοειδή απόβλητα, προκειμένου να αναβαθμιστεί η ποιότητά τους με τελικό στόχο να ικανοποιηθούν οι απαιτήσεις της οδηγίας 2000/60 για διασφάλιση «καλής» οικολογικής ποιότητας μέχρι το έτος 2015. / One of the main issues of the EU Water Framework Directive 2000/60 is the achievement of “good” ecological status for the surface waters by the year 2015. All European countries are obliged to assess the ecological quality of their surface water bodies and classify them into a five-quality class system, with a final purpose to ensure “good” status for Europe’s water bodies and prevent their further deterioration. Eleven sites located in the rivers Peiros - Parapeiros and Vouraikos (Western Greece), were sampled seasonally and analyzed using physicochemical, hydromorphological and biological data, in order to classify the water quality according to the aforementioned directive. Physicochemical classification was performed using the Nutrient Classification System, while the habitat quality was estimated by applying the River Habitat Survey methodology. Biological sampling was performed by application of the STAR AQEM methodology, while the ecological classification was achieved by utilizing the “REFCOND guidance for the relative roles of the physicochemical, hydromorphological and biological quality elements”. Various multivariate techniques (Canonical Correspondence Analysis, Cluster Analysis and MDS) revealed the most important environmental factors that affected the macroinvertebrate communities. According to the results of the study, half length of the rivers Peiros-Parapeiros and the 3/5 of the river Vouraikos were found not to fullfil the demands of the WFD, with their quality being assessed from “moderate” to “poor”. Agriculture, urbanization and hydromorphological alteration were the main factors that contributed to the water quality degradation of the rivers Peiros and Parapeiros, while the presence of dairy wastewaters has been assessed as the main reason for the quality degradation of Vouraikos river. Moreover, the results of the study revealed the valuable role of the riparian vegetation in absorbing a large part of the incoming pollution. Finally, the results reveal the obligation for focused actions to be taken for monitoring and improvement of water quality, in order to meet the demands of the Water Framework Directive 2000/60/EU for “good” ecological quality, by the year 2015.

Lakes provide essential ecosystem services to humankind, with the provision of freshwater likely being their most important contribution to human well-being. Therefore, it is mandatory to prevent freshwater lakes from harm in order to protect our livelihood. Pollution is known to put the health of our planet at risk, including our aquatic ecosystems. For European lowland surface waters, certain key organisms, including algae, crustacea, and fish, have been shown to be impacted by chemical pollution. However, currently little is known about the influence on other key organisms (e.g. macrophyte communities) and the spatial extent of these impacts. To close these gaps in knowledge and generally develop a better understanding of the impact of chemical pollution on our aquatic environment, is key for its efficient protection and the preservation of its ecosystem services. This dissertation aims to close these knowledge gaps and thereby increase our understanding of the impact of organic chemicals on our aquatic environment. During the course of this dissertation, two field studies and one literature review were conducted. The first field study was performed in eight lowland lakes of Schleswig-Holstein. Goal was to demonstrate that contaminated sediments prevent macrophyte communities from reaching a good ecological state. It was possible to show that sediment toxicity, driven by antifouling biocides and polycyclic aromatic hydrocarbons, is one of the factors that limit the ecological quality macrophyte communities can reach. The second field study was performed in eight lakes of the French Pyrenees. In this case, the aim was to explore the exposure and risk for waterbodies as remote as mountain lakes by organic chemicals. It was found that also mountain lakes are exposed to a wide variety of organic chemicals, including substances introduced via the atmosphere and local sources. All lakes under investigation were experiencing a chronic toxic risk for crustacea and three of eight lakes were even exposed to an acute toxic risk for crustacea. As this risk was also reflected in lowered abundancies of crustacea, this demonstrated that also waterbodies as remote as mountain lakes are impacted by chemical pollution. Following up on these findings, a literature review was performed. While generally little investigated, the data that could be found support the idea that toxic effects on mountain lakes might be widespread. The results of this thesis add to the growing knowledge, indicating that chemical pollution is jeopardizing the ecological quality of our planet and thereby, causing it to become unhealthy and dysfunctional. To protect our aquatic ecosystems, and planetary heath in general, it will be necessary to reduce our emissions of organic chemicals and use of particularly toxic substances.

The aim of this study is to examine the public preferences for urban riparian corridors in arid ‎regions, by testing to what extent people are willing to trade-off unmaintained ecological ‎landscape for aesthetics offered by specific micro and ‎macro environmental factors. Landscape ‎design reflects ecological and aesthetic values, and trade-offs are often made ‎between the two in ‎‎practice. In arid regions, water scarcity means riparian corridors are the ‎richest landscape ‎typology and the only ‎blue-green links for hundreds of miles. Pressure from ‎urbanization and ‎lack of eco-literacy contribute to negative ‎feedback loops which present dire ‎challenges for ‎migrating avifauna and regional wildlife. Regarding natural ‎resources and ‎biodiversity, where ‎multiple deliverable ‎ecosystem services rely on the quality and health of that ‎‎ecosystem, riparian ‎systems with high biomass are more desirable. Although this can be ‎achieved with low or no ‎‎maintenance riparian buffers, these unmaintained ecological landscapes ‎play an intrinsic role in ‎sustaining the ‎global ecosystem services and are important for the survival of the inhabitants ‎‎(avifauna). Ecological ‎landscapes are often subjected to trade-offs with aesthetic ‎landscapes that ‎include micro and ‎macro environmental factors such as manicured landscapes. It is accepted that ‎‎there is a ‎preference for aesthetics in landscape design; however, it is unclear how laypeople ‎prioritize ‎aesthetics ‎over different ecological factors in landscape scenes. This study uses a ‎Discrete Choice ‎Experiment (DCE) to elicit the ‎preferences of current or pretendant residents of ‎Jeddah City, Saudi Arabia for multiple landscape scenes. The method ‎combines ecological ‎landscape characteristics adopted from ‎the QBR index that are found in the study area in Jeddah ‎and aesthetic ‎characteristics, such as micro and macro environmental factors that are commonly ‎suggested in landscape design projects adapted from relevant visual preference studies (Alsaiari, ‎‎2018; Kenwick et al., 2009; Kuper‎ ‎,‎2017; Zhao et al., 2017). ‎DCE is a widely used method to ‎reveal preferences by analyzing the trade-offs people make ‎between ‎alternatives. Participants in ‎this study were exposed to a set of designs, which included ‎various configurations of ‎aesthetic ‎and ecological elements. Participants' choices revealed the influence of their ecological and ‎‎aesthetic values. Results show that minimal design interventions would prevent trading off the ‎ecological unmaintained landscape and that there are four subgroups with distinct homogeneous ‎preferences for the attributes affecting the appeal for the urban riparian corridor in Jeddah City. ‎Finally, results show that even though there are significant differences between subgroups based ‎on preferences, the demographic information is proportionally distributed in a way the means ‎differences diminish between the subgroups. ‎Findings in this study will equip ‎decision-makers ‎with operational definitions relating to riparian ‎landscape design and a method ‎that they can use ‎to minimize losses in ecological value over aesthetic value. This study will help‎ ‎researchers and ‎landscape architects advance visual preference research further into the domain ‎of empirical ‎‎studies.‎ ‎ / Doctor of Philosophy / Landscape architecture is a profession that entails planning and design outdoor spaces, ‎‎landmarks, and ‎structures to improve the built environment and increasing the quality of ‎‎people's lives by achieving ‎environmental, social, economic, and aesthetic outcomes‎. The ‎profession often reflects ecological and ‎aesthetic values, and trade-offs are often made ‎between ‎the two in ‎practice. These ecological values ‎represent environmental characteristics that are ‎important for the survival of wildlife (protected path ‎and safe habitat) and the overall ecosystem ‎‎(every being has a role that sustain the health of the ‎environment). Culturally, human is ‎accustomed to a slick-and-clean (tamped) looking plant within urban ‎developments (i.e., ‎neighborhoods). An example of the trade-off that often happen in practice between ‎the ‎ecological and aesthetic values is replacing an ecologically unmaintained plants that play ‎important ‎ecological role (i.e., wildlife habitat) with clean tamped plants to increase the value of ‎a real estate. Due ‎to the uncertainty surrounding people's acceptance of the features of these ‎ecological unmaintained ‎plants, especially when it entails introducing ecological riparian ‎landscape attributes within ‎neighborhoods for the first time, this dissertation focuses on both ‎assessing ecological elements ‎preferences within an urban arid region in Jeddah, Saudi Arabia ‎and assessing the extent to which ‎advanced analytical methods are capable of providing a better ‎understanding of ecological riparian ‎landscape attributes preference differences among a ‎seemingly homogenous sample of participants. ‎The increasing usage of manipulated images in ‎choice tasks inspired this dissertation. The results of the ‎study demonstrate that among the ‎relatively homogenous sample of participants that was recruited, ‎four significant preference ‎patterns have emerged, which could be used to describe and predict ‎preference for ecological ‎riparian landscape attributes and choice with great accuracy. The dissertation ‎also investigates ‎policy implications that might be beneficial in creating a ‎physical environment that ‎match public ‎preferences. ‎It also offers research implications and recommendations for landscape ‎architects ‎and urban designers on how to employ visual choice experiments, which have been well-‎‎developed in other research field

En la presente tesis se muestrearon ríos sobre los 2000 msnm (ríos altoandinos tropicales) que se distribuyen en la amplia región de los Andes del Norte (Ecuador) y los Andes Centrales (Perú) en Sudamérica. El muestreo de las 123 localidades se realizó en época seca, las cuales se seleccionaron tomando en cuenta su grado de alteración, que van desde sin o poca alteración (referencia) hasta muy alterados. En una primera instancia se analizaron las carácteristicas fisicoquímicas e hidromorfológicas de los ríos, las cuales mostraron una alta influencia de la altitud. Se registraron reducciones en la temperatura y oxígeno a medida que la altitud se incrementaba, por otra parte las diferencias en la heterogeneidad de los hábitats, así como la calidad del bosque de ribera fueron dos factores con un alta importancia al momento de caracterizar los ríos altoandinos. Se econtraron diferencias en la mineralización en los diferentes dominios morfotectónicos, siendo más elevados los valores de conductividad en las zonas del sur, debido a la geomorfología propia de cada zona. La comunidad bentónica mostro estar altamente influenciada por la altitud y la latitud. La altitud mostró intervenir positiva o negativamente en la abundancia y frecuencia de algunos géneros como Hyalella, Podonomopsis, Claudioperla, Anomalopsyche, Paltostoma, Rheotanytarsus, Camelobaetidius, etc. Por su parte, la latitud reveló la tendencia de algunos taxa a disminuir o aumentar su abundancia y frecuencia, tal es el caso de Anacroneuria, Camelobaetidius, Anchytarsus, Hagenulopsis, Claudioperla, Austrelmis, Smicridea, etc. Por otra parte y como punto novedoso para el conicimiento de la zona de estudio, se analizó a la familia Chironomidae a nivel de género, hecho importante para el conocimiento taxónomico de la familia en ríos tropicales de los Andes sobre los 2000 msnm, ya que no hay trabajos a este nivel taxonómico en la zona altoandina. La familia Chironomidae mostro patrones similares a los de la comunidad bentónica en general, sindo los factores relacionados con la altitud (oxígeno y temperatura) lo que determinan en gran medida su distrbución, sin embargo, al igua que el resto de la comunidad la heterogenidad de hábitats mostraron ser de suma importancia para la familia de los quironómidos. Además, la litografía y la biogeografía fueron dos factores que determinan la composición de esta familia. Con esta visión general, se analizaron los patrones de biodiversidad de estos ríos, donde se determinó que la comunidad bentónica altoandina tiene una amplia variabilidad en la diversidad local mientras que si analizamos la diversidad Gamma hay una tendencia a disminuir tanto a medida que la altitud y la latitud aumentan. Por su parte se evidenció cambios en la composición de la comunidad, la cual fue evidente también en ambos gradientes, sin embargo debido a la amplia heterogeneidad ambiental fue necesario analizar la reposición de especies a diferentes escalas de agrupación ya que sin esta corrección los cambios ambientales locales no permiten visualizar los patrones existentes en la comunidad, indicandonos la importancia de los factores locales en la biodiversidad regional. Finalmente, y con la recopilación de la estructura, composición y distribución de la fauna béntica, así como de la variabilidad ambiental tanto natural como antropogénica, se desarrolló un índice multimétrico que nos permite evaluar la calidad ecológica de los ríos altoandinos aplicable a una zona geográfica amplia. Los análisis previos al desarrollo del índice multimétrico demostraron que la variabilidad de la zona alta (localidades de páramo y puna) y la zona baja (localidades de bosque montano) era diferente. Posteriormente usando a las comunidades de macroinvertebrados acuáticos de las localidades de referencia se determinaron a dichas zonas como tipologías diferentes, las cuales se usaron para desarrollar el IMEERA-B (Bosque) y el IMEERA-P (Páramos y Punas). En nuestro estudio en la zona baja el gradiente de presión está determinado por la contaminación orgánica y la degradación hidromorfológica, y en la zona alta el gradiente está influenciado por la contaminación orgánica y la heterogeneidad del hábitat. Finalmente, se determinaron 6 métricas para IMEERA-B que evalúan la riqueza, el hábito y la tolerancia/intolerancia, y para el IMEERA-P se determinaron 4 métricas que evalúan la riqueza y la tolerancia/intolerancia. / STRUCTURE AND COMPOSITION OF AQUATIC MACROINVERTEBRATES COMMUNITIES IN HIGHLAND ANDEAN RIVERS OF ECUADOR AND PERU. DESIGN OF A MEASURE OF WATER QUALITY WITH MULTIMETRIC INDEXES In this thesis we sampled Highland Andean Rivers above 2000 m a.s.l. (tropical andean highland rivers) which are distributed in a wide geographical region of the North Andes (Ecuador) and Central Andes (Peru) in South America. In total 123 sites were sampled in dry season, which were selected taking into account the anthropogenic influence gradient, ranging from no alteration, little alteration (i.e., reference) to highly altered. The physico-chemical caracteristics of rivers showed a high altitud influence. We recorded a decrease in both temperature and oxygen as altitude increases. Habitat heterogeneity and the riverine forest quality were identified as determinant enviromental characteristics regarding the andean higland rivers studied. The mineralization show differences between the morphotectonics groups, while were the conductivity was higher at the south, depending on the geomorphology of each zone. The sampled macroinvertebrate assemblages were influenced by both latitudinal and altitudinal gradients. In detail, assemblages showed different gradient responses (positive or negative), depending of the organism and its requirements. The patterns of abundance and richness are probably determined by the environmental variability observed, and described by the temperature, oxygen, habitat heterogeneity and the presence, and absence of riverine forest. The family Chironomidae, as we expected, showed different responses depending of the genus, while the composition of the family was determined mainly by temperature, oxygen, lithography. and biogeography. We also studied the biodiversity patterns of Highland Andean Rivers rivers. The benthic community assemblage showed a high variability at local diversity (alpha diversity), while the gamma diversity decreased in both latitude and altitude gradients. Moreover, the community presented some discontinuities in the beta diversity. Regarding latitudinal gradient, the composition of assemblage changed in each morphological group, while altitude changes were described by vegetation types (mountain forest or páramo-puna) or presence or absence of riverine forest. Finally, using the aquatic macroinvertebrate communities of the reference sites, two different zones were identified as distinct from each other: from 2000 to 3500 m a.s.l and those sites at altitudes higher than 3500 m a.sl.. For such reasons two versions of a multi-metric index - the IMEERA index - were developed. The IMEERA B index includes six metrics evaluating richness, habit and tolerance/intolerance. The IMEERA P index was calculated using four metrics evaluating richness and tolerance/intolerance. Results showed that in lower altitudes (Bosque river type, IMEERA-B index), the pressure gradient was driven by the organic pollution and the hydromorphological degradation, while in higher altitudes (Páramo and Puna river types; IMEERA-P river type), the gradient was driven by the organic pollution and the habitat heterogeneity.

Les activités humaines, de loisir et professionnelles, vont en s’intensifiant sur les zones rocheuses intertidales. Le piétinement associé à ces activités, le remaniement des blocs pour rechercher des espèces consommables, ne sont pas sans incidence sur les biocénoses des milieux rocheux. Les conséquences de ces activités sur la structure et la dynamique des roches du médiolittoral et des champs de blocs de bas d’estran en particulier, nécessitent d'être caractérisées. A travers l’identification des espèces et descripteurs qui répondent le plus aux perturbations "piétinement des platiers rocheux" et "retournement des blocs par les pêcheurs à pied", des indicateurs écologiques simplifiés peuvent être dégagés et faciliter, à terme, le diagnostic de l’état de conservation de ces habitats. Les processus écologiques de dégradation et de déstructuration des biocénoses sous l'effet du piétinement passent par des interactions entre espèces très complexes. Les résultats d’expérimentations in situ soulignent des phénomènes de seuils très marqués, liés en particulier à la protection jouée par les algues brunes structurantes sur les autres espèces. L'étude du retournement des blocs par les pêcheurs à pied met en évidence une phase de mortalité presque totale des organismes fixés ou peu mobiles des blocs et une faible résilience de l’habitat. Le choix de stations de référence appropriées et l’utilisation des espèces et descripteurs les plus sensibles au retournement des blocs ont permis la création de deux indicateurs de perturbation. Déclinés à deux échelles spatiales différentes, ils sont applicables en routine par les scientifiques et les gestionnaires d’aires marines protégées. / Recreational and professional activities are intensifying on the rocky intertidal. The overturning of boulders and the trampling associated with human activities, have consequences on the structure and dynamic of rocky intertidal communities. Through the identification of species and descriptors that respond more to the disturbances “trampling of mediolittoral rock platforms” and “the overturning of low eulittoral boulders by hand-fishermen”, SMART indicators (Simple, Measurable, Achievable, Realistic, and Time limited indicator) can be created for the assessment of the conservation status of these habitats. The effects of trampling were tested with control approach. Experiments in situ underlined very complex interactions between species during the ecological processes of degradation of biocenoses. High thresholds of disturbance were also observed. They were particularly related to the protection played by structuring brown algae on other species. The study of boulder’s overturning highlighted a step of almost total mortality of fixed or low mobile organisms that live on upper or lower surfaces of boulders. Results also showed a low resilience of the habitat. The use of appropriate reference situations and of the most sensitive species to the boulder’s overturning, led to the creation of two ecological indicators. Declined to two different spatial scales, they may be applied routinely by scientists and managers of marine protected areas.