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Spatially and seasonally distributed information on transpiration (T) fluxes is limited in the tropics. Here, we applied a coupled isotope mass balance model to separate water fluxes of T and evapotranspiration (ET) from precipitation (P). The mean annual T was estimated at a resolution of 100 m for Costa Rica (51,100 km2) and a partitioning of monthly T and evaporation (E) for the 2370‐km2 San Carlos catchment. The dominant flux in the forest ecosystems was T with a mean annual T of 1086 mm that ranged from 700 mm in Tropical Montane Very Humid Forest to 1400 mm in Subtropical and Tropical Low Montane Rainforests. We estimated an average 85% of ET was T, which is concurrent with expectations for forested tropical regions, but varied according to model parameterization and data sources. A model comparison exercise showed a range of mean annual T estimates from 988 to 1465 mm and a range of T/P from 0.35 to 0.5 with temperature and relative humidity exhibiting the highest impact on the model results. Across Costa Rica, we estimated an average loss of precipitation by T of 38% (1085 mm), whereas interception (I) constitutes 10% (230 mm) and direct evaporation (E) only 7% (192 mm). Similarly, the results at the catchment scale indicated that monthly T contributes 76% (85‐mm monthly average) to total ET and E corresponds to 24% (24‐mm monthly average). The T rates exhibited an opposite seasonality to rainfall with highest T over the drier months from December to April with a peak in March (101–144 mm) and the minimum T in September (53–71 mm). Around 17% (79–130 mm) of precipitation over the catchment area is lost to T, both E (10–35 mm) and I (15–38 mm) correspond to 5%. Despite the inherent uncertainties of the data assumptions and simplifications, including data interpolation errors, the coupled isotope mass balance model showed in comparison to other global products reasonable water partitioning for different ecosystems in Costa Rica and the San Carlos catchment area. These results can help to evaluate the impact of land cover conversion on the hydrological cycle in Costa Rica, and the simple isotope‐based model could be transferred to different biomes of the tropics.

The Collective Article ‘New Mediterranean Biodiversity Records’ of the Mediterranean Marine Science journal offers the means to publish biodiversity records in the Mediterranean Sea. The current article is divided in two parts, for records of native and alien species respectively. The new records of native fish species include: the slender sunfish Ranzania laevis and the scalloped ribbonfish Zu cristatus in Calabria; the Azores rockling Gaidropsarus granti in Calabria and Sicily; the agujon needlefish Tylosurus acus imperialis in the Northern Aegean; and the amphibious behaviour of Gouania willdenowi in Southern Turkey. As regards molluscs, the interesting findings include Ischnochiton usticensis in Calabria and Thordisa filix in the bay of Piran (Slovenia). The stomatopod Parasquilla ferussaci was collected from Lesvos island (Greece); the isopod Anilocra frontalis was observed parasitizing the alien Pteragogus trispilus in the Rhodes area. The asteroid Tethyaster subinermis and the butterfly ray Gymnura altavela were reported from several localities in the Greek Ionian and Aegean Seas. The new records of alien species include: the antenna codlet Bregmaceros atlanticus in Saronikos Gulf; three  new fish records and two decapods from Egypt; the establishment of the two spot cardinal fish Cheilodipterus novemstriatus and the first record of the Indo-Pacific marble shrimp Saron marmoratus in semi-dark caves along the Lebanese coastline; the finding of Lagocephalus sceleratus, Sargocentron rubrum, Fistularia commersonii and Stephanolepis diaspros around Lipsi island (Aegean Sea, Greece); the decapod Penaeus hathor in Aegean waters; the decapod Penaeus aztecus and the nudibranch Melibe viridis in the Dodecanese islands; the finding of Pinctada imbricata radiata in the Mar Grande of Taranto (Ionian Sea, Italy) and the Maliakos Gulf (Greece).

EN EL PRESENTE ESTUDIO SE EVALUÓ EL IMPACTO DE LOS SISTEMAS silvopastoriles en la calidad del agua de las microcuencas de los ríos Bul bul y Paiwas, Matiguás, Nicaragua. Se seleccionaron 9 quebradas, 5 protegidas por bosque ripario y 4 no protegidas, ubicadas en fincas con sistemas silvopastoriles. Se establecieron 2 puntos de monitoreo por quebrada: a 50m de distancia de la naciente y en la zona de potreros. Se tomaron muestras de agua a las que se les realizó análisis físicoquímicos y bacteriológicos. En la época seca se registraron niveles bajos de O2D (oxígeno disuelto mg/L) y niveles altos de dureza total mg/L, mientras que en la época lluviosa se encontraron los niveles más altos de coliformes fecales. El resto de los parámetros evaluados fueron aptos para consumo humano. Se encontraron diferencias significativas a un (P <0,05) entre épocas para O2D mg/L y dureza total mg/L.

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