WATER DRIFT PATCH
WATER DRIFT PLUS
WATER DRIFT FREE

For individuals, drifting may be a mode of patch selection for invertebrates balancing resource acquisition and predation risk (e.g., Kohler and McPeek 1989). Invertebrate drift, the downstream transport of stream invertebrates, is a defining feature of running water systems at multiple levels of organization.

WATER DRIFT PLUS

Dans un contexte de réseaux trophiques, il est nécessaire de mieux comprendre la dynamique dérive-consommateur s’alimentant–ressource et d’améliorer la modélisation des flux de dérive pour évaluer de manière plus réaliste la capacité des habitats pour les poissons se nourrissant de la dérive. Pour les populations d’invertébrés, si le paradoxe de la persistance des populations dans le contexte de perte en aval a généralement été résolu en faisant appel à la théorie, de nombreuses questions demeurent quant aux conséquences de la dérive pour la dynamique des populations. Nous postulons que cela peut être inféré de manière qualitative à partir des conditions hydrauliques, de la périodicité diurne et de caractères propres aux taxons. L’amélioration des modèles prédictifs nécessite une meilleure résolution des milieux dans lesquels la dérive est mue, d’une part, par l’hydraulique (dérive passive) ou, d’autre part, par le comportement (dérive active). Nous passons en revue et résumons les processus associés à la dérive, en mettant l’accent sur leurs causes sous-jacentes, les conséquences pour les populations d’invertébrés et la dynamique trophique plus large, ainsi que les avancées récentes en modélisation prédictive de la dérive. les modèles d’habitat reposant sur la bioénergétique pour les poissons). Malgré un intérêt de longue date, de nombreux aspects de la dérive demeurent mal compris d’un point de vue mécaniste, ce qui limite les applications plus larges des réseaux trophiques (p. La dérive d’invertébrés, soit le transport vers l’aval d’invertébrés aquatiques, est un processus écologique fondamental dans les cours d’eau qui a d’importantes conséquences pour les poissons qui se nourrissent d’aliments à la dérive. In a food web context, there is a need to better understand drift-foraging consumer–resource dynamics and to improve modelling of drift fluxes to more realistically assess habitat capacity for drift-feeding fishes. For invertebrate populations, while the paradox of population persistence in the context of downstream loss has been generally resolved with theory, there are still many unanswered questions surrounding the consequences of drift for population dynamics. We posit this can be qualitatively inferred by hydraulic conditions, diurnal periodicity, and taxa-specific traits. Improving predictive models requires further resolving the environmental contexts where drift is driven by hydraulics (passive drift) versus behaviour (active drift). Here, we review and synthesize drift-related processes, focusing on their underlying causes, consequences for invertebrate populations and broader trophic dynamics, and recent advances in predictive modelling of drift. Despite long-standing interest, many aspects of drift remain poorly understood mechanistically, thereby limiting broader food web applications (e.g., bioenergetics-based habitat models for fish). This process is called downwelling.Invertebrate drift, the downstream transport of aquatic invertebrates, is a fundamental ecological process in streams with important management implications for drift-feeding fishes. This piles up the sea surface and carries the lower temperature water layers downwards. In this case, the surface waters flow against each other in the middle of the ice orbital circle. Since icebergs “sit” relatively deep in the water, they rotate at a lower speed than the water surrounding them, which leaves an ice-free shadow space in their “back” area. Small icebergs are also present in composition of ice and water. Their trajectories are shaped by an effect called Ekman drift, in which sea surface currents are created by the transfer of wind energy to seawater.Īccording to the Ekman model, deeper water layers move at a slower speed than higher ones because friction greatly reduces the energy transferred by the wind.

In this case, the crystals are probably only a few millimeters in size and the condensed fraction of ice and almost frozen water, which is called “fat ice” because it resembles an oil film on the water.

WATER DRIFT FREE

Strong and very cold (katabatic) downdrafts blowing from inside the ice sheet towards the coast caused a cloud free sky above the water surface. A counterclockwise (anticyclonic) movement of the near-surface water layer with the sea ice floating in it can be observed. Sentinel-3 and Sentinel-2 images show Terra Nova Bay, which lies to the west of the Ross Sea between the Drygalski Ice Sheet to the south and Cape Washington and Silverfish Bay to the north.

Water drift