Plattform Platform	Reise-Nr. Cruise-No.	Zeitraum Period	Projekt Project	Arbeitsgebiet Working area
Sonne	SO269	02.08.2019 - 03.09.2019	MEGAPOL	South China Sea

Fahrtleiter Chief Scientist	Institut Institute	Auslaufhafen Port of departure	Einlaufhafen Port of return	Stationskarte Station map	Schiffsroute Trackchart
Waniek Joanna	Leibniz-Institut fur Ostseeforschung, Warnemunde	Singapure	Hong Kong

Ziel der Reise / Objectives of Cruise:

The cruise SO269 aimed to study the marine environmental conditions in an area spanning from the northern shelf of the South China Sea towards the deep sea, to enhance our understanding of the effects of growing anthropogenic pressure in a highly dynamic marine ecosystem. This region is an excellent example of a subtropical adjacent sea and a natural laboratory to study the exchange processes between the land and the ocean (Pearl River), the variability of physical forcing (monsoon, circulation), the drastically increasing anthropogenic stress due to eutrophication, organic contaminants, microplastic, antibiotics following the development of a Megacity within the area Guangzhou-Hong Kong. Our results will help to quantify the marine element cycles (Nitrogen, Phosphorus and Carbon), allow the quantification and distribution of anthropogenic contamination as well as the degree of time-space variability of natural oceanic processes. The cruise contributed to the Sino-German MEGAPOL project Megacity's fingerprint in Chinese marginal seas: Investigation of pollutant fingerprints and dispersal, which is conducted within the scientific-technological cooperation's with China (WTZ China). The major objective of the SO269 cruise was to recognize and to trace the chemical and biogeochemical imprints of the rapid development in the Pearl River Estuary-South China Sea continuum by addressing the following questions: 1: Which physical processes are responsible for the observed pattern of natural and anthropogenic substances in the water column and sediments of the Pearl River Estuary-South China Sea continuum? 2: What are the extents of biogeochemical halos of megacities, anthropogenic pollutants and distribution of bio-indicators in water column and sediments in the study area, and what is the role of sediments here for mitigation of pollutants by sedimentation and/or neutralization? 3: Do different climatic settings, catchment geology, land-use and industrial activities impart regionally specific patterns on materials delivered to and deposited within Pearl River Estuary-South China Sea continuum? On 2nd of August at 9:00 am (LT) RV SONNE sailed from Singapore towards our working area close to the Pearl River Estuary within the South China Sea. In the morning hours of 6th of August the vessel reached the working area and the work started at station SO269-01 with hydrographic measurements followed by geological sampling. Over the next two days hydrographic and geological sampling continued along the transect L1. Transect L4 with 6 combined hydrographic and geological stations was finalized on 9.08.2019, and the work continued along transect L5 until 11.08.2019. We continued the investigations using CTD rosette, multi corer, gravity corer, multi closing net as well as in situ pumps until the morning of 14th of August along transect L6. Due to relatively high waves the deployment of the mooring was postponed to the afternoon of 14.08.2019. At 4 pm (LT) the mooring containing a 42 cup sediment trap, a nitrate sensor, and two current meters of which one is combined with CTD and fluorometer, double releaser unit, top buoyancy and 24 buoyancy spheres was successfully deployed for a period of two years. Using hydro-acoustics and ranging the final position of the mooring was estimated to be 18?47.273N, 114?7.573E. Our work on the central transect, L2, started in the morning of 15th of August, again combining hydrographic measurements and geological sampling, which finished at 18th of August. Unfortunately, on 16th of August we lost the microstructure profiler during the work at station SO269-73. Combination of relatively strong currents and waves caused the rip of the rope and the loss of the instrument. Until then we had conducted microstructure measurements at 12 locations, with 4 profiles on average. Our first 25 h station close to the Pearl River Estuary within the plume started on 19th of August, before we continued our sur

Messungen / Measurements

Verankerungen / Moorings