Summary of the project
The sustainability of marine ecosystem production is impacted by multi-stressors, such as physical processes, eutrophication, over-fishing and aquaculture. The objectives of the MEcoPAM project are to identify and characterize the interactions of marine biogeochemical cycles and marine ecosystems, and to understand the response of typical marine ecosystem production to multi-stressors, thereby improving our knowledge of the impact of multi-stressors on the sustainability of marine ecosystem production.
The research areas include several unique sub-ecosystems in the Bohai Sea, Yellow Sea, and East China Sea (e.g. the hypoxia zone off the Changjiang Estuary, and aquaculture sites in the Shandong Peninsula). The major scientific questions to be addressed are:
- What is the impact of multi-stressors on biogeochemical cycles in coastal ecosystems (e.g. hydrodynamic control of biogenic element cycles, coupling mechanism of primary production with biogeochemical processes)?
- How does ecosystem functioning in the hypoxia zone of the East China Sea respond to multi-stressors (e.g. the role of metabolism and redox processes on element cycles, impact of hypoxia on the function and structure of marine ecosystem, impact of open ocean and atmosphere)?
- What adaptive strategies of coastal aquaculture ecosystems to deal with multi-stressors (e.g. the supporting role of main biogeochemical processes in food production and food web trophodynamics of major biological functional groups, adaptive strategies to fishery management)?
In addition to field observations of the physical, chemical and biological properties of ecosystems in East China Sea, Changjiang Estuary and the coastal area of the Shandong Peninsula, historical data analysis, numerical modelling and microcosm experiments will be undertaken.
The program is structured around five sub-projects:
(1) Biogeochemical Dynamics of Marine Ecosystems
This sub-project is designed to study the linkages between external forcings and material cycles of seasonal hypoxia in the East China Sea and the areas of integrated multi-trophic aquaculture (IMTA) in the coastal Shandong Peninsula. The study will focus particularly on the transfer and pathways of carbon and trace elements in the shelf region. The proposed research topics have the following cross-linked components:
- Regulation of the carbon cycle on the East China Sea Shelf by the coupling of biogeochemical and hydrodynamic processes
- Identification of various sources of nutrients in the area of marine aquaculture and their impact on food web structure
- Influence of coastal hypoxia on the coupling of benthic systems with pelagic processes on the coast
- Discrimination of heterotrophic decomposition of organic matter and hydrodynamic processes on the change in particulate organic matter fluxes
- It is hoped that the implementation of this study will provide knowledge towards the understanding of biogeochemical dynamics on the transfer and transportation of biogenic and trace elements in the changing coastal ocean.
(2) Nutrient Cycles and Response to Multi-stressors
Field investigations, incubations and modelling studies will be conducted to determine the oxygen consumption and accompanying nutrient transfer during organic matter decomposition, feedback of greenhouse gases to the atmosphere and ocean, response of nutrient composition to environmental change and its impact on food webs, and to identify the main factors influencing nutrient transfer and turnover in the investigated ecosystems.
(3) Hydrodynamic Response to Multi-stressors and its Impact on the Supply of Nutrients
The aim of this sub-project is to explore the variability of the coastal hydrographic environments and their impacts on the supplying and transporting of the nutrients in Chinese seas. The research issues include temporal and spatial variability of the hydrographic environment under climate change and human activities, the impact of physical factors on water exchange, nutrient supply and transportation and primary production.
(4) Microbial Loop and Coupling with Biogeochemical Cycles
The microbial food web is an import component of the marine pelagic food web. It also plays an important role in biogeochemical processes in the ocean. This sub-project focuses on (1) the response of the microbial food web to biogeochemical processes and (2) the role of the microbial food web in the regeneration of biogenic elements in the Changjiang Estuary and areas used for aquaculture in Shandong Peninsula. These receive considerable fresh water input and heavy pressure of aquaculture, respectively. Field investigations will be carried out in the two areas to study the seasonal variations of the microbial processes. Microbial samples and in situ incubations will be analysed along with other projects in our program to understand the influence of anoxia and aquaculture animals and plants on the microbial processes.
(5) Feedback Mechanisms of Ecosystem Structure and Function to Climate Change and Human Activities
Field investigations will be undertaken in the aquaculture areas in Shandong Peninsula, microcosm and modelling studies conducted to analyse the effect of aquaculture, fishing and enhancement activities on the structure and function of the ecosystem, as well as the response of the ecosystem to multiple stresses in order to advance adaptive management strategies to maintain the sustainablity of the ecosystem.
Area of study
China Seas
TimeTable for activities
1 January 2011 – 31 December 2015