FIRST REPORT OF THE JGOFS/LOICZ CONTINENTAL MARGINS TASK TEAM

1. EXECUTIVE SUMMARY The Joint Global Ocean Flux Studies (JGOFS) and the Land Ocean Interactions in the Coastal Zone (LOICZ) are Core Projects of the International Geosphere-Biosphere Programme: A study of Global Change (IGBP). They both have a primary interest in material fluxes in the ocean. JGOFS focuses on carbon fluxes in the open ocean, with interest in the continental margins as inputs to the ocean. LOICZ focuses on the land-sea interface and the coastal zone, with interest in the shelf edge as a boundary of exchange with the open ocean. The region of the continental margins thus marks an intersection between these two projects. Recognising both this mutual interest and the importance of the continental margins, the Scientific Steering Committees (SSCs) of these two projects have established a Continental Margins Task Team (CMTT). The CMTT was established as a joint working group of the Scientific Steering committees of JGOFS and LOICZ which each nominated a co-chair and three members of the Task Team. To date, the work of the Task Team has been executed primarily by correspondence. Two ad hoc meetings of the co-chairs have occurred, and most members of the CMTT met in Texel, The Netherlands, on 16 April 1996. This document constitutes the first report of the CMTT back to the JGOFS and LOICZ SSCs. This document provides recommendations to the respective Core Project Offices (CPOs) to be followed in dealing with proposed or extant research on the open continental shelves, and secondarily to inform the National Committees of IGBP, JGOFS, and LOICZ as to how JGOFS and LOICZ are dealing with research of interest to these two IGBP projects. The report also makes recommendations for facilitating communication among scientists in these two IGBP core projects.

1.1 RECOMMENDATIONS That the CMTT (Dr Julie Hall as co-ordinator) organise a workshop (approximately 15 people to be held in Nigeria (~ October 1996), to: a) Prepare initial budgets of fluxes of water, carbon (C), nitrogen (N), and phosphorus (P) from the land, on the shelf, and at the oceanic boundary of selected “case study" sites (tentatively East China Sea, North Sea, Chile-Peru shelf, Gulf of Guinea). b) Produce a draft report, to be used as a background report for item 3, below. That the CMTT organise a joint JGOFS/LOICZ session dealing with continental margin fluxes of materials, to be held in conjunction with the LOICZ Open Science meeting in the Netherlands in the fall of 1997. a) the meeting will be aimed at a synthesis of present knowledge about material fluxes at the shelf margins and transformations on the shelf. b) The proceedings are to be published as a special issue of Continental Shelf Research or some other appropriate refereed journal. This document and the recommendations were approved by the JGOFS and LOICZ SSC’s at a joint meeting on April 18th in Bad Munstereifel, Germany.

1.2 Terms of Reference for the JGOFS/LOICZ CMTT I. The primary issues to be addressed by the CMTT are: (a) Develop guidelines to designate projects as JGOFS, LOICZ, or joint; and recommend mechanisms for dealing with projects which overlap both programmes. (b) Facilitate communication between JGOFS and LOICZ, including: (i) developing of compatible data management procedures; (ii) compilation of directories of scientists; (iii) communication among research projects; (iv) communication among discipline groups. (c) Encourage national and regional collaboration between JGOFS and LOICZ, including: (i) development of multidisciplinary studies in continental margin areas identified or suspected to be quantitatively important to carbon and nutrient transfers between shelf seas and open ocean; (ii) development of procedures for reviewing the progress of continental margin studies undertaken nationally and regionally. II. Specific tasks of the CMTT involve developing a structure for an initial joint JGOFS/LOICZ meeting and/or workshop designed to: (a) Synthesise current knowledge of carbon and nutrient fluxes in the continental margins; (b) Review existing protocols applicable to estimating carbon and nutrient fluxes in continental margins; (c) Facilitate exchange of information and enable scientists from developing countries to contribute expertise to regional programmes and global synthesis efforts; facilitate extrapolation from regional/national to global scales.

2. INTRODUCTION

2.1 General Statements about JGOFS and LOICZ The Joint Global Ocean Flux Studies (JGOFS) and the Land Ocean Interactions in the Coastal Zone (LOICZ) are two core projects in the International Geosphere-Biosphere Programme (IGBP). The primary goals of those two projects may be briefly summarised as follows: For JGOFS (IGBP/SCOR, 1992) the goal is to: Assess more accurately and understand better the processes controlling regional to global and seasonal to interannual fluxes of carbon between the atmosphere, surface ocean and ocean interior and their sensitivity to climate changes. This goal will be achieved through the following products, that serve as JGOFS objectives: an assessment of large-scale carbon fluxes, obtained from a greatly increased network of observations; a set of models that express our understanding of the processes controlling large-scale carbon fluxes; a procedure for observing the ocean in a routine, synoptic manner to detect possible changes in the ocean cycle in response to climate change; a well-cared-for data set, comprising observations made according to standard protocols and a system for making subsets of these data easily available to researchers; knowledge and understanding of fluxes across the continental margins, to provide reliable boundary conditions for global models; and, an increased number of countries with an interest and skill in planning JGOFS-type activities and making the appropriate measurements and global scale inferences. And for LOICZ (Pernetta & Milliman 1995) the goals are: to determine at global and regional scales: (i) the fluxes of materials between land, sea and atmosphere through the coastal zone; (ii) the capacity of coastal systems to transform and store particulate and dissolved matter; (iii) the effects of changes in external forcing conditions on the structure and functioning of coastal ecosystems. to determine how changes in land use, climate, sea level and human activities alter the fluxes and retention of particulate matter in the coastal zone, and affect coastal morphodynamics. to determine how changes in coastal systems, including responses to varying terrestrial and oceanic inputs of organic matter and nutrients, will affect the global carbon cycle and the trace gas composition of the atmosphere. to assess how responses of coastal systems to global change will affect the habitation and usage by humans of coastal environments, and to develop further the scientific and socio-economic bases for the integrated management of the coastal environment.

2.2 The Role of Continental Margins in the Transfer of Materials including C, N, and P A definition of continental margins is, “those provinces of continents and of the ocean which are associated with the boundary between these two first-order features of the earth". (Although continental margins occupy less than 10% of the total sea surface, they are disproportionately important for the following reasons: They are regions of active biogeochemical interactions between land and the open sea; they provide a pathway for receiving, transferring and transporting large amounts of terrigenous natural and anthropogenic materials from land to the open sea. The flux of this terrestrial material, its spatial and temporal variation, and its ultimate fate all need to be understood before we can construct overall budgets of carbon, nitrogen and phosphorus in the ocean. The rate of biological production per unit area of the continental margin can be several times higher than in the open ocean, due to nutrient inputs from land, coastal upwelling, and so forth. In addition, the growth of various types of marine organisms in shallow waters apparently presently accounts for about half of the calcium carbonate production in the marine environment. Quantitative understanding of the river fluxes of nutrients, the fates of these nutrients, and the spatial and temporal variability of metabolism are needed. The physical and biogeochemical processes occurring in the margins make these regions important for intense air-sea exchange of CO2, N2, N2O, CH4, DMS and other gases. However, the quantitative role of this region in the overall air-sea exchange of these gases needs to be better understood. The high biological productivity, combined with the shallow water depths of the margins and terrigenous inputs of organic matter, makes this region the site of high organic matter deposition and associated benthic remineralisation. It has been estimated that up to 50% of the annual primary production of continental margins may reach the sea floor, where much of it is remineralised in a redox environment, which is very different than that of open waters. Sedimentary processes are markedly different from water column processes and thus can greatly affect chemical mass balances in the ocean. The sediment accumulation rates on margins can be orders of magnitude higher than in open ocean regions. Therefore these sediments may locally contain high resolution records (especially in basins with anoxic bottom water) of processes that have occurred at the margins in response to variability of environmental conditions. Study of these sediments could therefore be useful in understanding controls on and rates of transfer of carbon and associated biogenic materials between water column and bottom sediments and the relation to long-term changes. Development of realistic global scale models for the oceanic carbon-nitrogen-phosphorus cycles requires knowledge of fluxes across various ocean boundaries. Therefore a good understanding of the fluxes between the margin and the open ocean is crucial to model development. Studies of coastal oceans are directly relevant to societal needs. Coastal regions are densely populated and are subject to human exploitation for food. These regions are responsive to environmental changes resulting from natural processes and human activities. The response of the coastal and margin environments to such perturbations, and how they affect the global carbon-nitrogen-phosphorus cycles, need to be better understood. Many important commercial and subsistence marine fisheries are based at the continental margins, where biological production tends to be much greater than in the open ocean. Exploitation of marine organisms by humans results in the removal of biomass from the sea and also may impact the functioning of the marine ecosystem, with consequent implications for carbon fluxes.

2.3 Objectives of JGOFS and LOICZ Continental Margin Studies Objectives of continental margin studies in the JGOFS context are listed in the JGOFS Implementation Plan (IGBP/SCOR, 1992): to quantify the exchange of carbon between given marginal zones and the open ocean; to understand the seasonal and interannual fluctuation of carbon fluxes and nutrient cycles due to physical and biogeochemical variations; to estimate exchanges between shelves, slopes, and the open ocean by lateral transport; to evaluate the importance of carbon deposition on the continental slope; to determine the air-sea CO2 exchange rates in upwelling areas; and to characterise those features of continental margins that enable extrapolation to the global scale. Relevant LOICZ activities listed under Focus 1 and Focus 3 of the LOICZ Implementation Plan (Pernetta & Milliman, 1995) are: catchment basin fluxes into coastal systems; atmospheric inputs to the coastal zone; exchange of energy and matter at the shelf edge; factors influencing the mass balance of materials in coastal systems, especially in relation to the cycling of organic matter; and, estimation, for the coastal zone, of the fluxes of N2O, CH4, DMS, and other climatologically important trace gases.

3. GUIDELINES FOR DESIGNATING JOINT JGOFS/LOICZ PROJECTS Research designed to elucidate processes occurring at the boundary between the open ocean and continental shelf seas is clearly of interest to both projects to define the conditions operating at the common boundary between the primary domain of each project. Hence such projects would be designated joint. In general, projects which are strongly tied to land inputs are appropriate for LOICZ, as are those dealing with depths less than 200 meters. Open ocean studies off the shelf are likely to fall into the purview of JGOFS. With this general division, most neritic studies, especially those in coastal areas are more likely to be related to LOICZ than to JGOFS. Projects on the mid-shelf or spanning the entire shelf are strong candidates to be considered joint JGOFS/LOICZ efforts. JGOFS and LOICZ have developed separate procedures for the categorisation of research contributing to the two Core Projects, hence it would be cumbersome and overly bureaucratic to consider continental margin research using the procedures of both projects in parallel. The CMTT will, therefore, function as the formal review body on behalf of both Projects for the designation of individual research projects or activities as joint JGOFS/LOICZ research. Following procedures determined at the national level, projects and proposals should be submitted by the Principal Investigators to the National LOICZ and/or JGOFS Committee(s). Following identification of the research as being concerned with continental margin studies, the recipient core Project Office will submit the research proposal to the co-chairs of the CMTT for consideration. The CMTT will decide if the project should be designated as joint JGOFS/LOICZ. In the event that the CMTT decides that a project is not joint, then the submission will be returned to the appropriate Core Project Office for consideration and categorisation as research relating to that Core Project alone.

4. FACILITATION OF COMMUNICATION BETWEEN JGOFS AND LOICZ There are two major points to communication between these projects. Data and databases within each of these projects should be managed in such a way that it can be shared readily between the projects. This is a relatively straightforward consideration, but explicit consideration and planning with Data Information Services (DIS) can ensure that this is readily accomplished. (LOICZ Data & Information System Plan, Boudreau et al. 1996). Information should be circulated freely between the two projects, concerning national or regional programmes dealing with continental margin research. As a first step towards implementing this point, Annex I of the publication arising from this report will contain programmes we are aware of at the publication time. A preliminary version of that Annex is available in this report; it will be edited into a consistent format which includes project name, short description, contact person (address, phone, fax, email). The CMTT will work with the LOICZ and JGOFS CPOs to develop this list into a WWW Home Page (http://keep.oc.ntu.edu.tw/cmtt) which will be maintained and updated by the CMTT and cross listed on the JGOFS (http://ads.smr.uib.no/jgofs/jgofs.htm), LOICZ (http://www.nioz.nl/loicz) home pages.

5. JGOFS/LOICZ COLLABORATION JGOFS field work is currently planned to be completed by the year 2000. LOICZ is just beginning. This suggests that the major initial collaboration between these two projects should be “intellectual collaboration" in the form of data synthesis, model development, and interaction between the modelling groups in each project. This will be initiated with a small workshop in Lagos in October 1996. The aim of this workshop is to; Gain a better understanding of fluxes between the Continental Margins and the Open Ocean and the rates of processing of material in the continental margin. The specific objectives are; Using four areas as case studies, participants will attempt to develop a consensus on the C, N and P fluxes based on the available data. The case study sites will be the East China Sea, Chile/Peru coast, North Sea and the Gulf of Guinea. Participants will also consider the utility of LOICZ nutrient budgeting guidelines as a common framework for the overall aim. The outputs from the workshop will be a draft report which will include a consensus paper from each of the case study regions and a technical overview. This report will be used as the primary background document for a much broader Continental Margins Workshop at the LOICZ Open Science Meeting which will be held in the Netherlands in 1997.

6. REFERENCES Boudreau, P.R., P.J.F. Geerders and J.C. Pernetta. 1996. LOICZ Data and Information System Plan. LOICZ/R&S/96-6, ii + 62 pp. LOICZ, Texel, The Netherlands. IGBP/SCOR. 1992. Joint Global Ocean Flux Study: Implementation Plan. Published jointly by the International Geosphere and Biosphere Programme, IGBP Report No. 23 and the Scientific Committee on Ocean Research, JGOFS Report No. 9. Pernetta, J.C. and J.D. Milliman (eds.). 1995. Land Ocean Interactions in the Coastal Zone Implementation Plan. IGBP Report No. 33. Stockholm Sweden. 215 pp.