Search results for "Underwater"

Early Jurassic (Sinemurian to basal Toarcian) ammonites of the Brescian Prealps (Southern Alps, Italy).

2017

This work provides a more precise up-to-date biostratigraphical framework of the Early Jurassic ammonite succession of the Brescian Prealps with more than seventy taxa for the Sinemurian, Pliensbachian and basal Toarcian corresponding to a about 30 horizons or faunal assemblages rather well correlable with the NW European standard zonation. These results are supported with already published data, new data from recent field investigations, revised contributions of different authors and with the study of the historical collection of the Museum of Natural Sciences of Brescia (Northern Italy). The biohorizons are referred to the Lower Jurassic carbonate series of the Brescian Prealps, cropping …

Optical types of inland and coastal waters

2017

Inland and coastal waterbodies are critical components of the global biosphere. Timely monitoring is necessary to enhance our understanding of their functions, the drivers impacting on these functions and to deliver more effective management. The ability to observe waterbodies from space has led to Earth observation (EO) becoming established as an important source of information on water quality and ecosystem condition. However, progress toward a globally valid EO approach is still largely hampered by inconsistences over temporally and spatially variable in-water optical conditions. In this study, a comprehensive dataset from more than 250 aquatic systems, representing a wide range of condi…

Growth of nucleation mode particles in the summertime Arctic: a case study

2016

Abstract. The summertime Arctic lower troposphere is a relatively pristine background aerosol environment dominated by nucleation and Aitken mode particles. Understanding the mechanisms that control the formation and growth of aerosol is crucial for our ability to predict cloud properties and therefore radiative balance and climate. We present an analysis of an aerosol growth event observed in the Canadian Arctic Archipelago during summer as part of the NETCARE project. Under stable and clean atmospheric conditions, with low inversion heights, carbon monoxide less than 80 ppbv, and black carbon less than 5 ng m−3, we observe growth of small particles,  <  20 nm in diameter, into sizes ab…

A European Multi Lake Survey dataset of environmental variables, phytoplankton pigments and cyanotoxins

2018

Under ongoing climate change and increasing anthropogenic activity, which continuously challenge ecosystem resilience, an in-depth understanding of ecological processes is urgently needed. Lakes, as providers of numerous ecosystem services, face multiple stressors that threaten their functioning. Harmful cyanobacterial blooms are a persistent problem resulting from nutrient pollution and climate-change induced stressors, like poor transparency, increased water temperature and enhanced stratification. Consistency in data collection and analysis methods is necessary to achieve fully comparable datasets and for statistical validity, avoiding issues linked to disparate data sources. The Europea…

Multiproxy dietary trait reconstruction in Pleistocene Hippopotamidae from the Mediterranean islands

2019

Abstract Geographically isolated insular species face energetic restrictions and commonly evolve adaptations that distinguish them from their mainland ancestors. During the Pleistocene, several Mediterranean islands were inhabited by now extinct Hippopotamidae. They underwent diverse changes in locomotion, dentition and body size. Based on these differences, it is supposed that they occupied different ecological niches depending on their respective faunal complexes and available resources. In this paper, we assess the paleoecology of dwarfed hippopotami from Crete, Malta, Sicily and Cyprus using a novel dental multiproxy approach. We applied dental topography analysis (SAGA-GIS) to measure …

Predicting future thermal habitat suitability of competing native and invasive fish species: From metabolic scope to oceanographic modelling

2015

Global increase in sea temperatures has been suggested to facilitate the incoming and spread of tropical invaders. Here, we determined the effect of temperature on the aerobic metabolic scope of two competing fish species, one native and one invasive, and we predicted their future thermal habitat suitability.

2015

Prey preference of top predators and energy flow across habitat boundaries are of fundamental importance for structure and function of aquatic and terrestrial ecosystems, as they may have strong effects on production, species diversity, and food-web stability. In lakes, littoral and pelagic food-web compartments are typically coupled and controlled by generalist fish top predators. However, the extent and determinants of such coupling remains a topical area of ecological research and is largely unknown in oligotrophic high-latitude lakes. We analyzed food-web structure and resource use by a generalist top predator, the Arctic charr Salvelinus alpinus (L.), in 17 oligotrophic subarctic lakes…

Dispersal of larval and juvenile seabream: Implications for Mediterranean marine protected areas

2015

International audience; In the marine context, information about dispersal is essential for the design of networks of marine protected areas (MPAs). Generally, most of the dispersal of demersal fishes is thought to be driven by the transport of eggs and larvae in currents, with the potential contribution of dispersal in later life stages relatively minimal.Using otolith chemistry analyses, we estimate dispersal patterns across a spatial scale of approximately 180 km at both propagule (i.e. eggs and larvae) and juvenile (i.e. between settlement and recruitment) stages of a Mediterranean coastal fishery species, the two-banded seabream Diplodus vulgaris. We detected three major natal sources …

Environmentally driven changes in Baltic salmon oxidative status during marine migration.

2020

The fitness and recruitment of fish stocks can be markedly affected by environmental disturbances including global warming, eutrophication and contamination. Understanding the effects of environmental stressors on salmon physiology during marine residence is of a global concern as marine survival has decreased. We present a unique combination of physiological responses - antioxidant defence and oxidative damage biomarkers, stable isotopes and contaminant exposure biomarkers - measured from adult Atlantic salmon (Salmo salar) collected at the Baltic Sea and studied in relation to environmental variables and fitness estimates. The results demonstrate that feeding populations of salmon display…

Symposium on “Climate Change and Molluscan Ecophysiology” at the 79thAnnual Meeting of the American Malacological Society

2015

Climate change has already had many observable effects on Earth. On land, glaciers and snowpacks have shrunk, tropical forests are being replaced by savannahs, and coastal areas have increased risks of flooding (e.g., IPCC 2007, Allan and Soden 2008, Dai 2010, NOAA 2010, Chen et al. 2011). In addition to sea-surface warming, climate change has altered the physical and chemical nature of the marine environment, including ocean acidification and expanding hypoxia. The scope and scale of future environmental change that individuals will undergo on land and in the sea will fundamentally influence the ecological and evolutionary responses of populations and species, dependent on their evolved ph…