Biološki i ekološki čimbenici koji utječu na rast ljuštura školjkaša

Bivalve mollusks incorporate life-history traits in their shells during growth making them valuable archives of environmental, biological and evolutionary information. This thesis provides insights into the biological and environmental drivers of shell growth in Callista chione, Glycymeris bimaculata and Glycymeris pilosa. The study was performed in the middle-eastern Adriatic Sea (Pag Bay, Cetina river mouth and Pašman Channel) from May 2014 until October 2015. A characterization of the feeding ecology of these species within their habitat analyzed several biochemical parameters including stable isotope and fatty acid composition. The reproductive behavior was studied applying two complementary approaches, histology and gonadosomatic index. Lastly, stable isotope analyses of carbonate samples were linked to high-resolution temperature records to describe shell microgrowth patterns. Spring and summer were identified as the periods with the best food quality in the particulate matter. Food resource partitioning was observed between C. chione and G. bimaculata at each site and the nitrogen isotopic composition of bivalve tissues was influenced by the presence of diazotroph biomass which differentiated among sites. Inter-site variations in the spawning timing and duration of C. chione were likely associated with temperature whereas in Glycymeris sp. spawning was not directly connected. Such small-scale biological responses are essential to address climate oscillation influences. Shell accretion took place between May and December pointing (i) temperature as an important determinant of shell growth (ii) food availability setting the limits for the growth season and (iii) the onset of gametogenesis close to the growth line formation, evidencing higher energy requirements for reproduction. These results contribute to knowledge on bivalve ecology in the Adriatic Sea and outlined the importance of coupling sclerochronology to ecological studies for a better understanding of species life-history traits.Školjkaši u svoje ljušture ugrađuju osobine životnog ciklusa, što ih čini vrijednim arhivima okolišnih, bioloških i evolucijskih podataka. Ovaj rad pruža uvid u biološke i ekološke čimbenike koji utječu na rast vrsta Callista chione, Glycymeris bimaculata i Glycymeris pilosa. Istraživanje je provedeno u istočnom dijelu srednjeg Jadrana (Paška uvala, ušće rijeke Cetine i Pašmanski kanal) u periodu od svibnja 2014. do listopada 2015. Karakterizacijom ekologije prehrane ovih vrsta u okviru njihovog okolnog staništa analizirano je nekoliko biokemijskih parametara, uključujući stabilne izotope i sastav masnih kiselina. Reproduktivno ponašanje se proučavalo primjenom dva komplementarna pristupa, histologije i gonadosomatskog indeksa. Analize stabilnih izotopa karbonatnih uzoraka su povezane sa zapisima temperature visoke rezolucije kako bi se opisali uzorci mikro-rasta. Proljeće i ljeto su identificirani kao razdoblja s najboljom kvalitetom hrane u mikroćesticama. Raspodjela izvora hrane je zamijećena između vrsta C. chione i G. bimaculata na svakoj lokaciji, a izotopni sastav dušika u tkivu školjkaša je bio pod utjecajem diazotrofne biomase koja se razlikovala među lokacijama. Varijacije među lokacijama, u vremenu i trajanju mriještenja vrste C. chione, su vjerojatno povezane s temperaturom, dok je kod vrste Glycymeris sp. mriještenje nije bilo izravno povezao. Takvi manji biološki odgovori su bitni za razumjevanje utjecaja klimatskih promjena. Rast ljušture se odvijao između svibnja i prosinca naglašavajući (i) temperaturu kao bitnu odrednicu rasta ljušture (ii) dostupnost hrane koja određuje granice sezone rasta i (iii) nastup gametogeneze u doba formiranja linije rasta, pokazujući veću potrebu za energijom tijekom razmnožavanja. Rezultati ovog istraživanja pridonose poznavanju ekologije školjkaša u Jadranskom moru, a istaknuli su važnost povezanosti sklerokronologije s ekološkim studijama za bolje razumijevanje osobina životnog ciklusa školjkaša

Description of the ecology of the Gulf of Lions shelf and slope area and identification of the areas that may deserve to be protected

64 pages, 13 figures, 1 tableThe Regional Activity Centre for Specially Protected Areas (UNEP-MAP-RAC/SPA), with support from the European Commission and the Mediterranean Trust Funds, started in 2008 an ambitious project to identify and establish Marine Protected Areas in the open seas, including the deep seas, in order to promote the establishment of a representative ecological network of protected areas in the Mediterranean. The first phase of the project was based on the provisions of the Protocol concerning Specially Protected Areas and Biological Diversity in the Mediterranean (SPA/BD Protocol) and was completed at the end of 2009. Its main result was the identification of twelve areas as priority conservation areas in the open seas, including the deep seas, likely to include sites that could be candidates for inclusion in the SPAMI list. One of these areas is the so-called Gulf of Lions shelf and slope area (Figure 1). [...]This document has been prepared in the framework of the project for supporting the establishment of MPAs in open seas, including deep seas, with financial support of the European CommissionPeer Reviewe

Bivalve trophic ecology in the Mediterranean: Spatio-temporal variations and feeding behavior

The trophic ecology of two bivalves, the clam Callista chione and the cockle Glycymeris bimaculata was studied using environmental and biochemical variables of the suspended particulate matter and the sediment. Samples were collected from two shallow sites, Pag and Cetina, in the coastal oligotrophic Mediterranean Sea, during a 17 month period. The temporal variation of the particulate matter reflected a mixture between marine and terrestrial sources throughout the year, with a clear marine influence during summer and fall, and predominance of terrestrial inputs during spring and winter. The digestive gland was a useful rapid turnover tissue, where the carbon isotope signal was species-specific and the nitrogen isotope one was site-specific. FA markers in the digestive gland revealed a mixed diet where Callista chione fed more upon fresh material than G. bimaculata which relied largely on bacteria-derived detritus. Overall, little feeding niche overlap was observed between the two species during the year, indicating resource partitioning, expected for a food-limited system. The present trophic ecology study in co-occurring species allowed identifying species-specific feeding adaptations to environmental variability

The benthic communities of the Cap de Creus canyon

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Prediabetes Is Associated with Increased Prevalence of Sleep-Disordered Breathing

Type 2 diabetes leads to severe nocturnal hypoxemia, with an increase in apnea events and daytime sleepiness. Hence, we assessed sleep breathing parameters in the prediabetes stage. A cross-sectional study conducted on 966 middle-aged subjects without known pulmonary disease (311 patients with prediabetes and 655 controls with normal glucose metabolism) was conducted. Prediabetes was defined by glycated hemoglobin (HbA1c), and a nonattended overnight home sleep study was performed. Participants with prediabetes (n = 311) displayed a higher apnea-hypopnea index (AHI: 12.7 (6.1;24.3) vs. 9.5 (4.2;19.6) events/h, p < 0.001) and hypopnea index (HI: 8.4 (4.0;14.9) vs. 6.0 (2.7;12.6) events/h, p < 0.001) than controls, without differences in the apnea index. Altogether, the prevalence of obstructive sleep apnea was higher in subjects with prediabetes than in controls (78.1 vs. 69.9%, p = 0.007). Additionally, subjects with prediabetes presented impaired measurements of the median and minimum nocturnal oxygen saturation, the percentage of time spent with oxygen saturations below 90%, and the 4% oxygen desaturation index in comparison with individuals without prediabetes (p < 0.001 for all). After adjusting for age, sex, and the presence of obesity, HbA1c correlated with the HI in the entire population (r = 0.141, p < 0.001), and the presence of prediabetes was independently associated with the AHI (B = 2.20 (0.10 to 4.31), p = 0.040) as well as the HI (B = 1.87 (0.61 to 3.14), p = 0.004) in the multiple linear regression model. We conclude that prediabetes is an independent risk factor for an increased AHI after adjusting for age, sex, and obesity. The enhanced AHI is mainly associated with increments in the hypopnea events

Biološki i ekološki čimbenici koji utječu na rast ljuštura školjkaša

Bivalve mollusks incorporate life-history traits in their shells during growth making them valuable archives of environmental, biological and evolutionary information. This thesis provides insights into the biological and environmental drivers of shell growth in Callista chione, Glycymeris bimaculata and Glycymeris pilosa. The study was performed in the middle-eastern Adriatic Sea (Pag Bay, Cetina river mouth and Pašman Channel) from May 2014 until October 2015. A characterization of the feeding ecology of these species within their habitat analyzed several biochemical parameters including stable isotope and fatty acid composition. The reproductive behavior was studied applying two complementary approaches, histology and gonadosomatic index. Lastly, stable isotope analyses of carbonate samples were linked to high-resolution temperature records to describe shell microgrowth patterns. Spring and summer were identified as the periods with the best food quality in the particulate matter. Food resource partitioning was observed between C. chione and G. bimaculata at each site and the nitrogen isotopic composition of bivalve tissues was influenced by the presence of diazotroph biomass which differentiated among sites. Inter-site variations in the spawning timing and duration of C. chione were likely associated with temperature whereas in Glycymeris sp. spawning was not directly connected. Such small-scale biological responses are essential to address climate oscillation influences. Shell accretion took place between May and December pointing (i) temperature as an important determinant of shell growth (ii) food availability setting the limits for the growth season and (iii) the onset of gametogenesis close to the growth line formation, evidencing higher energy requirements for reproduction. These results contribute to knowledge on bivalve ecology in the Adriatic Sea and outlined the importance of coupling sclerochronology to ecological studies for a better understanding of species life-history traits.Školjkaši u svoje ljušture ugrađuju osobine životnog ciklusa, što ih čini vrijednim arhivima okolišnih, bioloških i evolucijskih podataka. Ovaj rad pruža uvid u biološke i ekološke čimbenike koji utječu na rast vrsta Callista chione, Glycymeris bimaculata i Glycymeris pilosa. Istraživanje je provedeno u istočnom dijelu srednjeg Jadrana (Paška uvala, ušće rijeke Cetine i Pašmanski kanal) u periodu od svibnja 2014. do listopada 2015. Karakterizacijom ekologije prehrane ovih vrsta u okviru njihovog okolnog staništa analizirano je nekoliko biokemijskih parametara, uključujući stabilne izotope i sastav masnih kiselina. Reproduktivno ponašanje se proučavalo primjenom dva komplementarna pristupa, histologije i gonadosomatskog indeksa. Analize stabilnih izotopa karbonatnih uzoraka su povezane sa zapisima temperature visoke rezolucije kako bi se opisali uzorci mikro-rasta. Proljeće i ljeto su identificirani kao razdoblja s najboljom kvalitetom hrane u mikroćesticama. Raspodjela izvora hrane je zamijećena između vrsta C. chione i G. bimaculata na svakoj lokaciji, a izotopni sastav dušika u tkivu školjkaša je bio pod utjecajem diazotrofne biomase koja se razlikovala među lokacijama. Varijacije među lokacijama, u vremenu i trajanju mriještenja vrste C. chione, su vjerojatno povezane s temperaturom, dok je kod vrste Glycymeris sp. mriještenje nije bilo izravno povezao. Takvi manji biološki odgovori su bitni za razumjevanje utjecaja klimatskih promjena. Rast ljušture se odvijao između svibnja i prosinca naglašavajući (i) temperaturu kao bitnu odrednicu rasta ljušture (ii) dostupnost hrane koja određuje granice sezone rasta i (iii) nastup gametogeneze u doba formiranja linije rasta, pokazujući veću potrebu za energijom tijekom razmnožavanja. Rezultati ovog istraživanja pridonose poznavanju ekologije školjkaša u Jadranskom moru, a istaknuli su važnost povezanosti sklerokronologije s ekološkim studijama za bolje razumijevanje osobina životnog ciklusa školjkaša

La pesca recreativa a la costa catalana : Guia d'espècies

La pesca marítima recreativa és una activitat amb una llarga tradició, fortament arrelada al litoral Mediterrani. A Catalunya, els més de 550 km de costa, juntament amb la diversitat geomorfològica del nostre litoral, contribueixen a que hi hagi un gran nombre de practicants de pesca recreativa. En base a un estudi recent realitzat per la DGPAM (2020), s'estima que a Catalunya hi ha prop de 54.000 pescadors recreatius que practiquen almenys una de les tres modalitats: costa, embarcació o submarina. Com d'altres activitats humanes, la pesca recreativa és una font de pressió sobre el medi marí i els seus impactes sobre els recursos biològics i els ecosistemes on habiten han de ser considerats. Donat l'interès de l'administració pesquera catalana, així com de la comunitat de pescadors recreatius catalans perquè l'activitat pugui practicar-se de forma sostenible, aquesta guia aporta informació sobre les espècies objectiu de l'activitat, amb la finalitat de promoure hàbits de pesca responsables. La guia presenta il·lustracions per a 65 espècies objectiu i dona informació pràctica sobre les seves característiques biològiques, ecològiques i legals, per a millorar-ne el coneixement i promoure una activitat més sostenible a llarg termini, en benefici de tots. Diverses de les espècies de la guia són especialment vulnerables, sobre les quals cal tenir una conscienciació especial. Les espècies vulnerables es caracteritzen per tenir un creixement lent i una longevitat elevada, o bé per tenir un potencial reproductor baix, o bé per estar incloses en els convenis internacionals de protecció de la biodiversitat. Aquesta guia de butxaca pretén ser una eina útil per facilitar la identificació i la comparació d'algunes espècies objectiu i per conèixer més sobre el seu estat actual. La participació i col·laboració del pescador recreatiu és essencial per mantenir la compatibilitat entre la pesca recreativa i els recursos marins.Recomanacions de bones pràctiques: - No capturar més individus dels necessaris. Retenir només aquells que hagin de ser consumits en un entorn familiar i d'amics; la resta caldria alliberar-los vius al mar. - Respectar les talles mínimes, juvenils i espècies vulnerables i protegides.- Evitar l'ús d'hams petits per ajudar a disminuir les captures d'individus per sota la talla mínima legal o talla de primera maduresa. - En cas de pescar individus durant la seva etapa reproductora, es recomana la solta del peix viu a l'aigua, procurant tenir l'animal el mínim temps possible fora de l'aigua i intentant no malmetre'l al treure-li l'ham. - Si es desitja conservar la captura d'una espècie vulnerable, s'aconsella pescar un únic individu de la mateixa espècie a cada jornada de pescaPeer reviewe

La pesca artesanal en Cap de Creus: uso del espacio y valoración del impacto sobre los elementos clave del sistema marino

XVII Simposio Ibérico de Estudios de Biología Marina (SIEBM), 11-14 September 2012, Donostia-San SebastiánPeer reviewe

La política pública de vivienda en Colombia. CONFLICTO DE OBJETIVOS

El artículo se propone evidenciar la forma como entran tempranamente en conflicto los dos preceptos contenidos en el artículo 51 de la Constitución Política de Colombia, referente, por una parte, al derecho que tienen todos los colombianos a una vivienda digna y la obligación del Estado a hacerlo efectivo y, por otra, la promoción de planes de vivienda y a su adecuada financiación. Para esto, luego de revisar los contenidos predominantes de las normas en las que se desarrollan dichos preceptos, se identifican las decisiones tomadas explícita o implícitamente en ellas y los impactos que su aplicación tiene en las condiciones de producción de la vivienda, es decir, la forma como esas decisiones se están materializando. De esta manera se verifica la forma como se está resolviendo el conflicto planteado, en detrimento de la calidad y la asequibilidad de la vivienda, es decir, en contra de la satisfacción del derecho constitucional. El artículo concluye argumentando a favor de la configuración de los procesos de toma de decisiones de política pública en vivienda como un proceso social amplio, incluyente y complejo

Drivers of shell growth of the bivalve, Callista chione (L. 1758) - Combined it environmental and biological factors

WOS:000426027100014Seasonal shell growth patterns were analyzed using the stable oxygen and carbon isotope values of live-collected specimens of the bivalve Callista chione from two sites in the Adriatic Sea (Pag and Cetina, Croatia). Micromilling was performed on the shell surface of three shells per site and shell oxygen isotopes of the powder samples were measured. The timing and rate of seasonal shell growth was determined by aligning the delta O-18(shell)-derived temperatures so that the best fit was achieved with the instrumental temperature curve. According to the data, shells grew only at very low rates or not at all during the winter months, i.e., between January and March. Shell growth slowdown/shutdown temperatures varied among sites, i.e., 13.6 degrees C at Pag and 16.6 degrees C at Cetina, indicating that temperature was not the only driver of shell growth. Likely, seasonal differences in seawater temperature and food supply were the major component explaining contrasting growth rates of C. chione at two study sites. Decreasing shell growth rates were also associated with the onset of gametogenesis suggesting a major energy reallocation toward reproduction rather than growth. These results highlight the need to combine scier-ochronological analyses with ecological studies to understand life history traits of bivalves as archives of environmental variables