Senckenberg am Meer Wilhelmshaven



Lower Saxonian Ministry for
Science and Culture
Funding period                                 
Achim Wehrmann, Kristin Haynert         

Since the beginning of the Holocene sea level have rapidly risen due to deglaciation. The present-day North Sea shelf passed through several stages of coastal development starting with swamps and peat formation turning into brackish and tidal flat sedimentation. Sedimentation processes covered soils and corresponding biocoenoses as well as archaeological remains which allowed their conservation until to data. The submerged sediment layers of the North Sea region preserved an excellent archive of prehistoric key material which includes plants, animals, micro- and macrofossils and remains of prehistoric cultures. This material will enable us to reconstruct postglacial history, vegetation, landscape as well as the environment development of sea level and climate change in the Wadden Sea region. The interdisciplinary research project WASA consists of three subprojects and integrates the  scientific disciplines of geosciences, biosciences and cultural sciences to a multi-proxy approach of exploration, analysis and predictive modelling. In the frame of the study we will focus on actuopalaentological analyses of micro- and macrofossils. The composition of the benthic communities allows defining of specific coastal environments, which provides information about abiotic environmental parameters by species-specific ecological ranges, especially at the land-sea transition area, the intertidal and shallow subtidal.

Wadden Sea of Lower Saxony


GeoArchives I/II - Signals of Climate and Landscape change preserved in southern African Geoarchives

Projektträger Jülich
Funding period I  2013-2016                                              
Funding period II 2016-2018
Achim Wehrmann, Irka Schüller

Within the wave-dominated and high-energy depositional environment of the southwestern African coast, lagoons and related saltpans and sabkhas represent one of the few areas in which sediments originating from both marine and terrestrial sources have accumulated under calm conditions. This allowed a more or less continuous depositional record of the mid to late Holocene. Open marine ingressions within these lagoons are defined by diverse mollusk assemblages, indicating different climatic conditions. Terrestrial climate archives in southern Africa are provided by analysis of high resolution sedimentary records of salt pans in the southwestern Kalahari. Both, the marine and terrestrial archives will provide a deep insight into the climatic evolution and environmental conditions in southern Africa during the Late Quaternary. Climatic and associated environmental variability has not only a strong effect on the sedimentary and ecological record but also on the composition and diversity of the indigenous microbial communities.

Thus, this project will study the sedimentary, (bio-)geochemical and microbiological record of the lagoons with respect to their transitional setting at the land-ocean interface along the southwest African coast. This allows a detailed reconstruction of regional sea-level fluctuations, the position of the Angola-Benguela Front and hinterland processes under changing climatic conditions. Furthermore, the depositional record of southern African salt pans will be studied using the same approach to document palaeoclimatic and palaeoenvironmental variations in the continental southern African region.

The project is carried out in close cooperation with our project partners from TU Munich, GFZ Potsdam and ICBM Oldenburg

salt marsh namibian coast

Salt marsh of the Sandwich Bay lagoon (Namibian Coast)


 Kalahari salt pan

Omongwa salt pan (southwestern Kalahari, Namibia)



Klimaveränderung und Bioinvasionen als Steuerungsfaktoren von Ecosystem Engineering: Die Dynamik benthischer Gemeinschaften

Funding period                                  
Alexandra Markert, Achim Wehrmann

Ecosystem engineers are characterized by modifying physical parameters of their environment resulting in a variety of habitat relevant processes - especially when the ecosystem engineer is an alien species. Hence, community structure (biodiversity, species richness and abundance) of the associated fauna may be altered.The bioinvasion and massive spread of the non-native Pacific oyster Crassostrea gigas in the intertidal of the Wadden Sea has an strong impact _mce_on resident blue mussel beds (Mytilus edulis) which transform increasingly into oyster reefs. Within this project we investigate the temporal modifications in community structure due to the change in ecosystem engineering species - from Mytilus edulis to Crassostrea gigas. Additionally, promoted by climate change, the novel habitat characteristics may facilitate the invasions of other non-native species.


Ecosystem Pacific oyster reef
(Wadden Sea of Lower Saxony) 



Ausbreitung der Pazifischen Auster

Funding period                               
Alexandra Markert, Achim Wehrmann

Blue mussel beds (Mytilus edulis) in the intertidal of the Wadden Sea are increasingly dominated by Pacific oysters (Crassostrea gigas) which entails economical damage for the blue mussel fishery in the area. Besides possible risks, the spread of the Pacific oyster may as well include new opportunities like breeding and commercialization. The crop of cultured plots of mussel fishers underlies strong ministerial controls concerning food safety. This is not true for wild Pacific oysters so far - no surveying or monitoring system regarding microbial or chemical risks exists for oyster reefs. It is alarming, that tourists and other consumers more and more collect Pacific oysters for consumption. There is as well evidence, that irrespective of food law regulations the collected Pacific oysters are presented in gastronomy. Within this project we investigate 12 sites in the Wadden Sea of Lower Saxony. We collect Pacific oysters and blue mussels once a year at all sites, every 3 month at 3 sites and 1 site gets sampled monthly. All samples - Pacific oysters and blue mussels - are analyzed by their content in human pathogenic germs (co-partner LAVES, Cuxhaven). Additionally, population dynamics of blue mussels and Pacific oysters are recorded annually at all sites.

Health risk Pacific oyster? 



Prozesse und Dynamik holozäner Verlandungszonen im Gebiet des Jadebusens

Funding period                           

Martina Karle, Achim Wehrmann

The Jade Bay in its today’s dimension was created by medieval storm surges. Up to the beginning of these marine intrusions vast salt-marshes covered the area. As those parts of the coastal landscape are very sensitive indicators for sea level changes, they act as sedimentological archives. So this part of the project deals with the change of the coastal landscape during the Holocene sea level rise focussing on former salt marsh belts, silting-up zones and erosive tidal creeks. By sedimentological and palaeoecological investigations in sediment cores the position, structure and extension of these structural features at the land-sea interface can be reconstructed giving an idea of the processes and reactions taking place during a changing sea level. As vegetation and diatom associations indicate a high resolution position in relation to the level of mean high water, a facies analysis may lead to a reconstruction of different mean high water levels and their respective coastlines in the past 10.000 years.
The main emphasis is put on the region of a flooded area during medieval storm tides, the so called “Schwarzes Brack”, southwest of Wilhelmshaven. Furthermore, existing data from the State Authority for Mining, Energy and Geology of Lower Saxony (LBEG, Hannover) will be used and interpreted with regard to climate indicators in order to reconstruct the evolution of the coastal region.

reed belt
Reed belt of the Jade Bay