333 resultados para FUCUS-SERRATUS


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The ecology of mosquitoes were studied (Diptera: Culicidae) in areas of Serra do Mar State Park, State of São Paulo, Brazil. Systematized monthly human bait collections were made three times a day, for periods of 2 or 3 h each, in sylvatic and rural areas for 24 consecutive months (January 1991 to December 1992). A total of 24,943 specimens of adult mosquitoes belonging to 57 species were collected during 622 collective periods. Coquillettidia chrysonotum was the most frequent collected mosquito (45.8%) followed by Aedes serratus (6.8%), Cq. venezuelensis (6.5%), Psorophora ferox (5.2) and Ps. albipes (3.1%). The monthly averages of temperature and relative humidity were inserted in the ten-year average limits of maximum and minimum of the previous ten-years. Rainfall accompanied the curve of the ten-year averages. Those climatic factors were influential in the incidence of some species; temperature: Anopheles cruzii, An. mediopunctatus, Ae. scapularis, Ae. fulvus, Cq. chrysonotum, Cq. venezuelensis, Runchomyia reversa, Wyeomyia dyari, Wy. confusa, Wy. shannoni, Wy. theobaldi and Limatus flavisetosus; relative humidity: Ae. serratus, Ae. scapularis, Cq. venezuelensis and Ru. reversa; rainfall: An. cruzii, Ae. scapularis, Ae. fulvus, Cq. venezuelensis Ru. reversa, Wy. theobaldi and Li. flavisetosus.

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The mosquito (Diptera: Culicidae) ecology was studied in areas of Serra do Mar State Park, State of São Paulo, Brazil. Systematized biweekly human bait collections were made three times a day, for periods of 2 or 3 h each, in sylvatic and rural areas for 24 consecutive months (January 1991 to December 1992). A total of 24,943 adult mosquitoes belonging to 57 species were collected during 622 collective periods. Aedes scapularis, Coquillettidia chrysonotum, Cq. venezuelensis, Wyeomyia dyari, Wy. longirostris, Wy. theobaldi and Wy. palmata were more frequently collected at swampy and at flooded areas. Anopheles mediopunctatus, Culex nigripalpus, Ae. serratus, Ae. fulvus, Psorophora ferox, Ps. albipes and the Sabethini in general, were captured almost exclusively in forested areas. An. cruzii, An. oswaldoi and An. fluminensis were captured more frequently in a residence area. However, Cx. quinquefasciatus was the only one truly eusynanthropic. An. cruzii and Ae. scapularis were captured feeding on blood inside and around the residence, indicating that both species, malaria and arbovirus vectors respectively, may be involved in the transmission of these such diseases in rural areas.

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The ecology of mosquito species (Diptera: Culicidae) was studied in areas of the Serra do Mar State Park, State of São Paulo, Brazil. The influence of the lunar cycle and the daily biting rhythms of mosquito populations were analyzed. Systematized biweekly human bait collections were made in a silvatic environment for 24 consecutive months (January 1991 to December 1992). A total of 20,591 specimens of adult mosquitoes belonging to 55 species were collected from 545 catches. Sabethini species were captured exclusively during daylight periods, with the exception of Trichoprosopon digitatum, while members of Anophelinae predominated during nocturnal hours. Members of the subfamily Culicinae that were collected primary during nocturnal periods included Culex nigripalpus, Coquillettidia chrysonotum and Cq. venezuelensis while daytime catches included Psorophora ferox and Ps. albipes. Others members of culicines mosquitoes that were collected during both day and night included: Aedes serratus, Ae. scapularis and Ae. fulvus. Lunar cycles did not appear to influence the daily biting rhythms of most mosquito species in the area, but larger numbers of mosquitoes were collected during the new moon. Ae. scapularis were captured mainly during the full moon.

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BACKGROUND: Prospective assessment of pedicled extrathoracic muscle flaps for the closure of large intrathoracic airway defects after noncircumferential resection in situations where an end-to-end reconstruction seemed risky (defects of > 4-cm length, desmoplastic reactions after previous infection or radiochemotherapy). METHODS: From 1996 to 2001, 13 intrathoracic muscle transpositions (6 latissimus dorsi and 7 serratus anterior muscle flaps) were performed to close defects of the intrathoracic airways after noncircumferential resection for tumor (n = 5), large tracheoesophageal fistula (n = 2), delayed tracheal injury (n = 1) and bronchopleural fistula (n = 5). In 2 patients, the extent of the tracheal defect required reinforcement of the reconstruction by use of a rib segment embedded into the muscle flap followed by temporary tracheal stenting. Patient follow-up was by clinical examination bronchoscopy and biopsy, pulmonary function tests, and dynamic virtual bronchoscopy by computed tomographic (CT) scan during inspiration and expiration. RESULTS: The airway defects ranged from 2 x 1 cm to 8 x 4 cm and involved up to 50% of the airway circumference. They were all successfully closed using muscle flaps with no mortality and all patients were extubated within 24 hours. Bronchoscopy revealed epithelialization of the reconstructions without dehiscence, stenosis, or recurrence of fistulas. The flow-volume loop was preserved in all patients and dynamic virtual bronchoscopy revealed no significant difference in the endoluminal cross surface areas of the airway between inspiration and expiration above (45 +/- 21 mm(2)), at the site (76 +/- 23 mm(2)) and below the reconstruction (65 +/- 40 mm(2)). CONCLUSIONS: Intrathoracic airway defects of up to 50% of the circumference may be repaired using extrathoracic muscle flaps when an end-to-end reconstruction is not feasible.

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Studies have shown that both carbon dioxide (CO2) and octenol (1-octen-3-ol) are effective attractants for mosquitoes. The objective of the present study was to evaluate the attractiveness of 1-octen-3-ol and CO2 for diurnal mosquitoes in the southeastern Atlantic forest. A Latin square experimental design was employed with four treatments: CDC-light trap (CDC-LT), CDC-LT and 1-octen-3-ol, CDC-LT and CO2 and CDC-LT with 1-octen-3-ol and CO2. Results demonstrated that both CDC-CO2 and CDC-CO2-1-octen-3-ol captured a greater number of mosquito species and specimens compared to CDC-1-octen-3-ol; CDC-LT was used as the control. Interestingly, Anopheles (Kerteszia) sp. was generally attracted to 1-octen-3-ol, whereas Aedes serratus was the most abundant species in all Latin square collections. This species was recently shown to be competent to transmit the yellow fever virus and may therefore play a role as a disease vector in rural areas of Brazil.

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To classify mosquito species based on common features of their habitats, samples were obtained fortnightly between June 2001-October 2003 in the subtropical province of Chaco, Argentina. Data on the type of larval habitat, nature of the habitat (artificial or natural), size, depth, location related to sunlight, distance to the neighbouring houses, type of substrate, organic material, vegetation and algae type and their presence were collected. Data on the permanence, temperature, pH, turbidity, colour, odour and movement of the larval habitat's water were also collected. From the cluster analysis, three groups of species associated by their degree of habitat similarity were obtained and are listed below. Group 1 consisted of Aedes aegypti. Group 2 consisted of Culex imitator, Culex davisi, Wyeomyia muehlensi and Toxorhynchites haemorrhoidalis separatus. Within group 3, two subgroups are distinguished: A (Psorophora ferox, Psorophora cyanescens, Psorophora varinervis, Psorophora confinnis, Psorophora cingulata, Ochlerotatus hastatus-oligopistus, Ochlerotatus serratus, Ochlerotatus scapularis, Culex intrincatus, Culex quinquefasciatus, Culex pilosus, Ochlerotatus albifasciatus, Culex bidens) and B (Culex maxi, Culex eduardoi, Culex chidesteri, Uranotaenia lowii, Uranotaenia pulcherrima, Anopheles neomaculipalpus, Anopheles triannulatus, Anopheles albitarsis, Uranotaenia apicalis, Mansonia humeralis and Aedeomyia squamipennis). Principal component analysis indicates that the size of the larval habitats and the presence of aquatic vegetation are the main characteristics that explain the variation among different species. In contrast, water permanence is second in importance. Water temperature, pH and the type of larval habitat are less important in explaining the clustering of species.

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Background: Chronic post-lobectomy empyema is rare but may require space obliteration for infection control. We report our experience by using a tailored thoracomyoplasty for this specific indication with respect to infection control and functional outcome. Patients and Methods: We retrospectively analysed 17 patients (11 men, 6 women) with chronic post-lobectomy empyema and treated by thoracomyoplasty in our institution between 2000 and 2011. All patients underwent an initial treatment attempt by use of chest tube drainage and antibiotics except those with suspicion of pleural aspergillosis (n=6). In 5 patients, bronchus stump insufficiency was identified at preoperative bronchoscopy. A tailored thoracoplasty was combined with a serratus anterior - rhomboid myoplasty which also served to close a broncho-pleural fistula, if present. The first rib was resected in 11/17 patients. Results: The 90-day mortality was 11.7%. Thoracomyoplasty was successful in all surviving patients with respect to infection control, space obliteration and definitive closure of broncho-pleural fistula, irrespective of the type of infection, the presence of a broncho-pleural fistula and whether a 1st rib resection was performed . Post-lobectomy pulmonary function testing before and after thoracoplasty revealed a mean predicted FEV1 of 63.0±8.5% and 51.5±4.2% (p=0.01), and a mean predicted DLCO of 59.8±11.6% and 54.5±12.5%, respectively. Postoperative shoulder girdle dysfunction and scoliosis were prevented in patients willing to undergo intense physiotherapy. Conclusions: Tailored thoracomyoplasty represents a valid option for patients with chronic post-lobectomy empyema without requiring a preceding open window thoracostomy. Space obliteration and infection control was equally obtained with and without first rib resection.

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Este trabalho lista as espécies e aponta a ocorrência de Culicinae, com base em coletas de adultos realizadas no período de setembro de 2001 a agosto de 2002, em 11 zonas fisiográficas do Estado, busca de informações bibliográficas e verificação de exemplares em coleções. São relacionadas 57 espécies, sendo que 22 constituem novas ocorrências para o Rio Grande do Sul. São ampliados os locais de ocorrência de Aedeomyia squamipennis, Culex chidesteri, Culex quinquefasciatus, Haemagogus leucocelaenus, Mansonia titillans, Ochlerotatus albifasciatus, Ochlerotatus crinifer, Ochlerotatus fluviatilis, Ochlerotatus scapularis, Ochlerotatus serratus, Psorophora confinnis, Psorophora ferox, Sabethes aurescens, Trichoprosopon pallidiventer e Uranotaenia lowii.

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BACKGROUND: Chronic post-lobectomy empyema is rare but may require space obliteration for infection control. We report our experience by using a tailored thoracomyoplasty for this specific indication with respect to infection control and functional outcome. METHODS: We retrospectively analyzed 17 patients (11 men, 6 women) with chronic postlobectomy empyema who were treated by thoracomyoplasty in our institution between 2000 and 2011. All patients underwent an initial treatment attempt by use of chest tube drainage and antibiotics except those with suspicion of pleural aspergillosis (n = 6). In 5 patients, bronchus stump insufficiency was identified at preoperative bronchoscopy. A tailored thoracoplasty was combined with a serratus anterior-rhomboid myoplasty, which also served to close a bronchopleural fistula, if present. The first rib was resected in 11 of 17 patients. RESULTS: The 90-day mortality was 11.7%. Thoracomyoplasty was successful in all surviving patients with respect to infection control, space obliteration, and definitive closure of bronchopleural fistula, irrespective of the type of infection, the presence of a bronchopleural fistula, or whether a first rib resection was performed. Postlobectomy pulmonary function testing before and after thoracoplasty revealed a mean predicted FEV(1) of 63.0% ± 8.5% and 51.5% ± 4.2% (p = 0.01) and a mean predicted DLCO of 59.8% ± 11.6% and 54.5% ± 12.5%, respectively. Postoperative shoulder girdle dysfunction and scoliosis were prevented in patients willing to undergo intense physiotherapy. CONCLUSIONS: Tailored thoracomyoplasty represents a valid option for patients with chronic postlobectomy empyema without requiring a preceding open window thoracostomy. Space obliteration and infection control were equally obtained with and without first rib resection.

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OBJECTIVES: Prospective evaluation of tracheo-carinal airway reconstructions using pedicled extrathoracic muscle flaps for closing airway defects after non-circumferential resections and after carinal resections as part of the reconstruction for alleviation of anastomotic tension. METHODS: From January 1996 to June 2006, 41 patients underwent tracheo-carinal airway reconstructions using 45 extrathoracic muscle flaps (latissimus dorsi, n=25; serratus anterior, n=18; pectoralis major, n=2) for closing airway defects resulting from (a) bronchopleural fistulas (BPF) with short desmoplastic bronchial stumps after right upper lobectomy (n=1) and right-sided (pleuro) pneumonectomy (n=13); (b) right (n=9) and left (n=3) associated with partial carinal resections for pre-treated centrally localised tumours; (c) partial non-circumferential tracheal resections for pre-treated tracheal tumours, tracheo-oesophageal fistulas (TEF) and chronic tracheal injury with tracheomalacia (n=11); (d) carinal resections with the integration of a muscle patch in specific parts of the anastomotic reconstruction for alleviation of anastomotic tension (n=4). The airway defects ranged from 2 x 1 cm to 8 x 4 cm and involved up to 50% of the airway circumference. The patients were followed by clinical examination, repeated bronchoscopy, pulmonary function testing and CT scans. The minimum follow-up time was 6 months. RESULTS: Ninety-day mortality was 7.3% (3/41 patients). Four patients (9.7%) sustained muscle flap necrosis requiring re-operation and flap replacement without subsequent mortality, airway dehiscence or stenosis. Airway dehiscence was observed in 1/41 patients (2.4%) and airway stenosis in 1/38 surviving patients (2.6%) responding well to topical mitomycin application. Follow-up on clinical grounds, by CT scans and repeated bronchoscopy, revealed airtight, stable and epithelialised airways and no recurrence of BPF or TEF in all surviving patients. CONCLUSIONS: Tracheo-carinal airway defects can be closed by use of pedicled extrathoracic muscle flaps after non-circumferential resections and after carinal resections with the muscle patch as part of the reconstruction for alleviation of anastomotic tension.

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Phlorotannins are the least studied group of tannins and are found only in brown algae. Hitherto the roles of phlorotannins, e.g. in plant-herbivore interactions, have been studied by quantifying the total contents of the soluble phlorotannins with a variety of methods. Little attention has been given to either quantitative variation in cell-wall-bound and exuded phlorotannins or to qualitative variation in individual compounds. A quantification procedure was developed to measure the amount of cell-wall-bound phlorotannins. The quantification of soluble phlorotannins was adjusted for both large- and small-scale samples and used to estimate the amounts of exuded phlorotannins using bladder wrack (Fucus vesiculosus) as a model species. In addition, separation of individual soluble phlorotannins to produce a phlorotannin profile from the phenolic crude extract was achieved by high-performance liquid chromatography (HPLC). Along with these methodological studies, attention was focused on the factors in the procedure which generated variation in the yield of phlorotannins. The objective was to enhance the efficiency of the sample preparation procedure. To resolve the problem of rapid oxidation of phlorotannins in HPLC analyses, ascorbic acid was added to the extractant. The widely used colourimetric method was found to produce a variation in the yield that was dependent upon the pH and concentration of the sample. Using these developed, adjusted and modified methods, the phenotypic plasticity of phlorotannins was studied with respect to nutrient availability and herbivory. An increase in nutrients decreased the total amount of soluble phlorotannins but did not affect the cell-wall-bound phlorotannins, the exudation of phlorotannins or the phlorotannin profile achieved with HPLC. The presence of the snail Thedoxus fluviatilis on the thallus induced production of soluble phlorotannins, and grazing by the herbivorous isopod Idotea baltica increased the exudation of phlorotannins. To study whether the among-population variations in phlorotannin contents arise from the genetic divergence or from the plastic response of algae, or both, algae from separate populations were reared in a common garden. Genetic variation among local populations was found in both the phlorotannin profile and the content of total phlorotannins. Phlorotannins were also genetically variable within populations. This suggests that local algal populations have diverged in their contents of phlorotannins, and that they may respond to natural selection and evolve both quantitatively and qualitatively.

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The objective of my thesis is to assess mechanisms of ecological community control in macroalgal communities in the Baltic Sea. In the top-down model, predatory fish feed on invertebrate mesograzers, releasing algae partly from grazing pressure. Such a reciprocal relationship is called trophic cascade. In the bottom-up model, nutrients increase biomass in the food chain. The nutrients are first assimilated by algae and, via food chain, increase also abundance of grazers and predators. Previous studies on oceanic shores have described these two regulative mechanisms in the grazer - alga link, but how they interact in the trophic cascades from fish to algae is still inadequately known. Because the top-down and bottom-up mechanisms are predicted to depend on environmental disturbances, such as wave stress and light, I have studied these models at two distinct water depths. There are five factorial field experiments behind the thesis, which were all conducted in the Finnish Archipelago Sea. In all the experiments, I studied macroalgal colonization - either density, filament length or biomass - on submerged colonization substrates. By excluding predatory fish and mesograzers from the algal communities, the studies compared the strength of the top-down control to natural algal communities. A part of the experimental units were, in addition, exposed to enriched nitrogen and phosphorus concentrations, which enabled testing of bottom-up control. These two models of community control were further investigated in shallow (<1 m) and deep (ca. 3 m) water. Moreover, the control mechanisms were also expected to depend on grazer species. Therefore different grazer species were enclosed into experimental units and their impacts on macroalgal communities were followed specifically. The community control in the Baltic rocky shores was found to follow theoretical predictions, which have not been confirmed by field studies before. Predatory fish limited grazing impact, which was seen as denser algal communities and longer algal filaments. Nutrient enrichment increased density and filament length of annual algae and, thus, changed the species composition of the algal community. The perennial alga Fucus vesiculosusA and the red alga Ceramium tenuicorne suffered from the increased nutrient availabilities. The enriched nutrient conditions led to denser grazer fauna, thereby causing strong top-down control over both the annual and perennial macroalgae. The strength of the top-down control seemed to depend on the density and diversity of grazers and predators as well as on the species composition of macroalgal assemblages. The nutrient enrichment led to, however, weaker limiting impact of predatory fish on grazer fauna, because fish stocks did not respond as quickly to enhanced resources in the environment as the invertebrate fauna. According to environmental stress model, environmental disturbances weaken the top-down control. For example, on a wave-exposed shore, wave stress causes more stress to animals close to the surface than deeper on the shore. Mesograzers were efficient consumers at both the depths, while predation by fish was weaker in shallow water. Thus, the results supported the environmental stress model, which predicts that environmental disturbance affects stronger the higher a species is in the food chain. This thesis assessed the mechanisms of community control in three-level food chains and did not take into account higher predators. Such predators in the Baltic Sea are, for example, cormorant, seals, white-tailed sea eagle, cod and salmon. All these predatory species were recently or are currently under intensive fishing, hunting and persecution, and their stocks have only recently increased in the region. Therefore, it is possible that future densities of top predators may yet alter the strengths of the controlling mechanisms in the Baltic littoral zone.

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Undervattensmiljön i skärgårdarna och de kustnära områdena i norra Östersjön är mångformiga och produktiva. Arternas levnadsmil-jöer styrs bl.a. av bottentyp, exponeringsgrad och ljustillgång. Kunskap och information om undervattensarterna är av stor vikt för en hållbar planering av kust- och havsmiljön. Denna rapport beskriver indelningen av de viktigaste undervattenshabitaten i norra Östersjöns kustvatten samt hur ett naturvärde på dessa miljöer kan uppskattas på basen av de olika ekologiska funktioner som habitatet uppfyller. De mest inflytelserika mänskliga hoten, både små- och storskaliga, som allvarligt kan hota habitatens fortbestånd behandlas också. Habitaten som beskrivs är både av typen hårdbotten och mjukbotten. Hårdbottenssamhällena bildar distinkta bälten från ytan mot bott-nen: trådalgszonen, zonen med stora fleråriga brunalger (Fucus vesiculosus, F. radicans), rödalgszonen och blåmusselzonen (Mytilus edulis/trossulus). Mjukbottensamhällena är uppbyggda kring ålgräs (Zostera marina), andra vattenlevande kärlväxter eller kransalger. En stor del av både de grunda och djupa mjukbottnarna saknar vegetation och samhällena struktureras då av ryggradslösa djur i och på sedi-mentytan. Habitaten har klassificerats och värderats enligt en tvåstegsmodell. Först har habitaten namngivits efter den dominerande arten eller artgruppen som bestämts enligt täckningsgrad. Därefter har varje habitat getts ett värde enligt sin ekologiska betydelse. Naturvärdet är indelat i skalan 1-5. Projektet NANNUT – The Nature and Nurture in the Northern Baltic Sea – har gjort inventeringar av undervattensmiljön på olika håll av kusterna och skärgårdarna i Finland 2010-2011. Målsättningen har varit att utveckla enkla och kostnadseffektiva metoder både för kartering och värdering av undervattenshabitat. Det huvudsakliga undersökningsområdet var förlagt till Raseborgsstad i södra Finland.

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Saaristojen ja rannikkoalueiden vedenalainen luonto pohjoisella Itämerellä on monimuotoista ja tuottavaa. Lajien elinympäristöjen erilaisuutta säätelee mm. pohjan laatu, avoimuus ja valonsaanti. Vedenalaislajiston tuntemus on hyvin tärkeää kestävässä rannikko- ja merialueiden suunnittelussa. Tämä raportti kuvailee tärkeimpien pohjoisen Itämeren rannikkovesien vedenalaiselinympäristöjen jaottelun sekä miten näiden ympäristöjen luontoarvoa voidaan luokitella kyseisen ympäristön ekologisten toimintojen perusteella. Myös elinympäristöjen säilymistä uhkaavat ihmisen aiheuttamat laajat ja pienemmät uhat esitellään raportissa. Kuvaillut elinympäristöt edustavat sekä pehmeän että kovan pohjan vedenalaisluontoa. Kovan pohjan elinympäristöt muodostavat erillisiä vyöhykkeitä mentäessä meren pinnasta pohjaan: rihmalevävyöhyke, monivuotisten, suurien ruskolevien vyöhyke (Fucus vesiculosus, F. radicans), punalevävyöhyke ja sinisimpukkavyöhyke (Mytilus edulis/trossulus). Kuvaillut pehmeän pohjan elinympäristöt rakentuvat meriajokkaan (Zostera marina),muiden vedessä elävien putkilokasvien tai näkinpartaislevien ympärille. Suuressa osassa sekä matalista että syvistä pehmeistä pohjista ei ole ollenkaan kasvillisuutta ja silloin eliöyhteiskunnan muodostaa hienoaineksen päällä ja sisällä elävät selkärangattomat eläimet. Elinympäristöt on luokiteltu ja arvotettu kaksiportaisen mallin mukaan. Ensin elinympäristö on nimetty peittävyyden perusteella vallitsevan lajin tai lajiryhmän mukaan. Tämän jälkeen jokaisella elinympäristölle annettiin arvo sen ekologisen tärkeyden perusteella. Luontoarvot on luokiteltu asteikoilla 1-5. NANNUT-hanke (The Nature and Nurture in the Northern Baltic Sea) on tehnyt vedenalaiskartoituksia eri puolilla Suomen rannikkoa ja saaristossa vuosina 2010 – 2011. Tavoitteena on ollut kehittää yksinkertaisia ja kustannustehokkaita menetelmiä sekä vedenalaisluonnon kartoittamiseen että sen arvottamiseen. Pääasiallinen tutkimus alue sijaitsi Raaseporin kunnan alueella Etelä-Suomessa.

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Macroalgae are the main primary producers of the temperate rocky shores providing a three-dimensional habitat, food and nursery grounds for many other species. During the past decades, the state of the coastal waters has deteriorated due to increasing human pressures, resulting in dramatic changes in coastal ecosystems, including macroalgal communities. To reverse the deterioration of the European seas, the EU has adopted the Water Framework Directive (WFD) and the Marine Strategy Framework Directive (MSFD), aiming at improved status of the coastal waters and the marine environment. Further, the Habitats Directive (HD) calls for the protection of important habitats and species (many of which are marine) and the Maritime Spatial Planning Directive for sustainability in the use of resources and human activities at sea and by the coasts. To efficiently protect important marine habitats and communities, we need knowledge on their spatial distribution. Ecological knowledge is also needed to assess the status of the marine areas by involving biological indicators, as required by the WFD and the MSFD; knowledge on how biota changes with human-induced pressures is essential, but to reliably assess change, we need also to know how biotic communities vary over natural environmental gradients. This is especially important in sea areas such as the Baltic Sea, where the natural environmental gradients create substantial differences in biota between areas. In this thesis, I studied the variation occurring in macroalgal communities across the environmental gradients of the northern Baltic Sea, including eutrophication induced changes. The aim was to produce knowledge to support the reliable use of macroalgae as indicators of ecological status of the marine areas and to test practical metrics that could potentially be used in status assessments. Further, the aim was to develop a methodology for mapping the HD Annex I habitat reefs, using the best available data on geology and bathymetry. The results showed that the large-scale variation in the macroalgal community composition of the northern Baltic Sea is largely driven by salinity and exposure. Exposure is important also on smaller spatial scales, affecting species occurrence, community structure and depth penetration of algae. Consequently, the natural variability complicates the use of macroalgae as indicators of human-induced changes. Of the studied indicators, the number of perennial algal species, the perennial cover, the fraction of annual algae, and the lower limit of occurrence of red and brown perennial algae showed potential as usable indicators of ecological status. However, the cumulated cover of algae, commonly used as an indicator in the fully marine environments, showed low responses to eutrophication in the area. Although the mere occurrence of perennial algae did not show clear indicator potential, a distinct discrepancy in the occurrence of bladderwrack, Fucus vesiculosus, was found between two areas with differing eutrophication history, the Bothnian Sea and the Archipelago Sea. The absence of Fucus from many potential sites in the outer Archipelago Sea is likely due to its inability to recover from its disappearance from the area 30-40 years ago, highlighting the importance of past events in macroalgal occurrence. The methodology presented for mapping the potential distribution and the ecological value of reefs showed, that relatively high accuracy in mapping can be achieved by combining existing available data, and the maps produced serve as valuable background information for more detailed surveys. Taken together, the results of the theses contribute significantly to the knowledge on macroalgal communities of the northern Baltic Sea that can be directly applied in various management contexts.