Leibniz Center for Tropical Marine Ecology

About: Leibniz Center for Tropical Marine Ecology is a facility organization based out in Bremen, Germany. It is known for research contribution in the topics: Coral reef & Reef. The organization has 267 authors who have published 526 publications receiving 19151 citations.

Effects of natural and human-induced hypoxia on coastal benthos

Abstract: . Coastal hypoxia (defined here as Hypoxia alters both the structure and function of benthic communities, but effects may differ with regional hypoxia history. Human-caused hypoxia is generally linked to eutrophication, and occurs adjacent to watersheds with large populations or agricultural activities. Many occurrences are seasonal, within estuaries, fjords or enclosed seas of the North Atlantic and the NW Pacific Oceans. Benthic faunal responses, elicited at oxygen levels below 2 ml L−1, typically involve avoidance or mortality of large species and elevated abundances of enrichment opportunists, sometimes prior to population crashes. Areas of low oxygen persist seasonally or continuously beneath upwelling regions, associated with the upper parts of oxygen minimum zones (SE Pacific, W Africa, N Indian Ocean). These have a distribution largely distinct from eutrophic areas and support a resident fauna that is adapted to survive and reproduce at oxygen concentrations

Mangroves, a major source of dissolved organic carbon to the oceans

Abstract: [1] Organic matter, which is dissolved in low concentrations in the vast waters of the oceans, contains a total amount of carbon similar to atmospheric carbon dioxide To understand global biogeochemical cycles, it is crucial to quantify the sources of marine dissolved organic carbon (DOC) We investigated the impact of mangroves, the dominant intertidal vegetation of the tropics, on marine DOC inventories Stable carbon isotopes and proton nuclear magnetic resonance spectroscopy showed that mangroves are the main source of terrigenous DOC in the open ocean off northern Brazil Sunlight efficiently destroyed aromatic molecules during transport offshore, removing about one third of mangrove-derived DOC The remainder was refractory and may thus be distributed over the oceans On a global scale, we estimate that mangroves account for >10% of the terrestrially derived, refractory DOC transported to the ocean, while they cover only <01% of the continents' surface

Impacts of hypoxia on the structure and processes in pelagic communities (zooplankton, macro-invertebrates and fish)

Abstract: . Dissolved oxygen (DO) concentration in the water column is an environmental parameter that is crucial for the successful development of many pelagic organisms. Hypoxia tolerance and threshold values are species- and stage-specific and can vary enormously. While some fish species may suffer from oxygen values of less than 3 mL O2 L−1 through impacted growth, development and behaviour, other organisms such as euphausiids may survive DO levels as low as 0.1 mL O2 L−1. A change in the average or the range of DO may have significant impacts on the survival of certain species and hence on the species composition in the ecosystem with consequent changes in trophic pathways and productivity. Evidence for the deleterious effects of oxygen depletion on pelagic species is scarce, particularly in terms of the effect of low oxygen on development, recruitment and patterns of migration and distribution. While planktonic organisms have to cope with variable DOs and exploit adaptive mechanisms, nektonic species may avoid areas of unfavourable DO and develop adapted migration strategies. Planktonic organisms may only be able to escape vertically, above or beneath the Oxygen Minimum Zone (OMZ). In shallow areas only the surface layer can serve as a refuge, but in deep waters many organisms have developed vertical migration strategies to use, pass through and cope with the OMZ. This paper elucidates the role of DO for different taxa in the pelagic realm and the consequences of low oxygen for foodweb structure and system productivity. We describe processes in two contrasting systems, the semi-enclosed Baltic Sea and the coastal upwelling system of the Benguela Current to demonstrate the consequences of increasing hypoxia on ecosystem functioning and services.