The meeting starts as a session on Asian Deltas: their
evolution and recent changes of ICAMG-V in Bangkok on January 16, followed by
two day excursion on January 17-18, and two day scientific meeting in Ayutthaya
on January 19-20. The hotel in Bangkok on January 15-16 is Miracle Grand Convention
Hotel, and the Krungsri River Hotel on January 17-20 for excursion and scientific
meeting in Ayutthaya.
The registration fee of IGCP-475 and APN Mega-Deltas includes excursion, accommodation
in Ayutthaya, and all meals from lunch on January 17 to breakfast on January
21, not includes the accommodation and meals in Bangkok. If you are interested
in participating in this meeting, please contact Dr. Yoshiki Saito (e-mail:
[email protected]).
INTRODUCTION
River deltas are among the most significant settings on Earth, in terms of their
human population, infrastructure, and resources such as agriculture, fisheries,
hydrocarbons, and wildlife. Such importance has fueled decades of research on
Western Hemisphere river deltas, such as the Mississippi, Rhine, and Nile. In
contrast, research on the many river deltas of South, Southeast, and East Asian
region began in earnest only last 20 years. The recent studies of these Asian
systems reveal that they are distinct from existing models because of regional
factors such as (1) a monsoon-dominated climate, (2) young, mountainous catchment
geology, (3) high-energy coastal settings, (4) large water and sediment discharges
and (5) tectonic activity. In addition, these Asian river deltas including Oceania
region also serve as major gateways for chemical and particulate fluxes to the
global ocean, including >75% of worldwide sediment discharge.
Moreover, the developing nations of these Asian region have long suffered from
numerous river delta-related hazards. These countries would benefit from a better
understanding of the controls and responses of their fluvial delta systems.
Over the course of the next 5 years, this project seeks to significantly improve
our understanding of Asian river deltas by (1) synthesizing abundant recent
research results, (2) bridging the traditional gaps between terrestrial, coastal,
and marine research, and (3) identifying the major needs and goals of future
research. Furthermore, in pursuing these goals we expect significant advances
in the fundamental research of monsoon-driven sediment dispersal systems.
OBJECTIVES
The project’s overall aim is to assemble a collective knowledge of river-delta
systems in the monsoon Asia-Pacific region, with the intent for capacity building
and advancing basic research in developing nations. Climate, tectonic, and coastal
regimes in this region are very dynamic and drive many large, active river-delta
systems. These systems also support an immense human population and comprise
an important part of regional economies through agriculture, fisheries, shipping,
infrastructure, and natural resources. To address the broad-range of interests
for the proposed DeltaMAP project, from basic to applied research, the following
key issues have been identified:
? Sediment Transport Patterns and Processes
? River Discharge and Sediment Load
? Sequence Stratigraphy and Reservoir Geometry
? Coastal Plain Development
? Alluvial Valleys
? Climate, Paleomonsoons, and Paleohydrology
? Earthquake History and Impacts
? Early and Modern Human Impacts
? Tropical Storms, Surges, and Tsunamis
? Comprehensive Delta Models for MAP Region
WORK PLAN
To address the broad interests of the project, the study will involve five working
sub-groups that will each focus on a specific aspect. These working groups will
also have a team leader who will oversee research and project activities . The
working groups will include the following:
- Late Quaternary Delta Stratigraphy and Correlation
- River-Delta Processes and Controls
- Human Impacts, Sustainable Development, and Geohazard Mitigation
- Quantitative Modeling of Delta Process, Response, and Stratigraphy
In addition to the above working groups, the DeltaMAP
project will also have regional coordinators who will organize multidisciplinary
efforts for individual delta systems within their area. The major areas include
South (Pakistan to Bangladesh), Southeast (Myanmar to Hong Kong), East (east
China to Korea and Japan), and Oceania (Indonesia to Papua New Guinea).
Based on the working groups and regional divisions, the project committee will
consist of nine group/regional directors and two general executive officers.
Although this number of leaders will require greater effort and organization,
we feel that the benefits are significant. The project will have greater impact
if participants are directly involved and have more ownership of the study.
This approach will also allow us to involve more members of developing nations
and support capacity building and professional development.
LOCATION OF MAJOR FIELD ACTIVITIES
China – Huanghe (Yellow River) delta, Changjiang (Yangtze) delta, Zhujiang
(Pearl River)
delta, deltas of Bohai Sea, others
Vietnam – Song Hong (Red River) delta, Mekong River delta
Thailand – Chao Phraya river delta
Indonesia – Mahakam River delta, Digul River delta, Kapuas River delta,
others
Malaysia – Baram River delta, Rajang River delta, others
Papua New Guinea – Fly River delta, Markam River delta, others
Myanmar – Irrawaddy River delta, Salween River delta
Bangladesh – Ganges-Brahmaputra River delta
India – Ganges River delta, Krishna River delta, Godavari River delta,
Cauveri River delta,
Narmada River delta, Mahanadi delta, others
Pakistan – Indus delta
Japan – Kurobe river delta, others
Korea – Keum river delta, Han river delta, others
Background
The Asian coast supports many large and distinct river
deltas, comprising abundant natural resources and an immense human population.
These deltas are located in seven different APN nations, and include the Huanghe
(Yellow), Changjiang (Yangtze), Pearl, Red, Mekong, Chao Phraya, Irrawaddy,
Ganges-Brahmaputra, and Indus river deltas. The world community has become increasingly
aware that these deltaic environments are vulnerable to numerous and frequent
geo-hazards, resulting from storms, floods, droughts, and sea-level rise. In
another respect, humans are also degrading the coastal environment through engineering
projects (e.g., river dykes and dams), urbanization, and the over-utilization
of natural resources (e.g., groundwater, coastal forests).
Recently, major efforts have been put forth to assess the potential impacts
that global change may have on these delta systems. However, most such assessments
have been based on a gross over-simplification of delta behavior, as well as
a limited database for Asian deltas. Although some background information can
be based on delta research from other parts of the world, recent findings from
the Asian mega deltas reveal that these systems are fundamentally distinct from
existing models. Notably, the following characteristics of Asian deltas contribute
to their unique behavior: 1) monsoon control, 2) high sediment loads, 3) high,
strongly seasonal water discharge, 4) large coastal tide ranges, and 5) silt-sand
dominated sediment texture, and 6) tectonic activity (only in a few systems).
Thus, we propose a 2-year study that will focus on: 1) establishing a comprehensive
conceptual model for Asian mega deltas, where unique geologic conditions play
a critical role for delta response to various natural and anthropogenic forcings;
2) an improved understanding of the dynamic processes of Asian mega deltas in
order to provide useful information for future coastal vulnerability assessments;
and 3) the significance of #1-2 above for the sustainable development of this
densely-populated region.
Deltaic systems are very complex and involve significant feedbacks among climate,
catchment, deltaic depocenter and continental-margin controls. This truth is
not appreciated by many researchers who are trying to predict the impact of
future changes on Asian deltas. Furthermore, understanding the response of deltas
to environmental change becomes more complicated when anthropogenic modifications
are considered. These complexities must be taken into account to yield valid
vulnerability assessments for deltaic systems. In fact, the scientists involved
in the proposed study represent almost all Asian mega deltas (appendix I, II)
and have done extensive research in the region over the past decade. However,
these relatively isolated works have not yet revealed their broader regional
significance, which in association with risk assessment is a primary goal of
the proposed project. Past failures in coastal planning suggest that the lack
of a fundamental geological context for risk-assessment studies has harmed our
socioeconomic and sustainable development, and this will continue in the future
unless better information can be brought to regional planners and managers.
Primary Objectives
A. To establish a comprehensive conceptual model for Asian mega deltas, based
on the integration of large databases existing in various delta systems, including
both the geological framework of the delta and the dynamic material fluxes from
Himalayan/Tibetan plateau to the delta estuaries (e.g., sediment load, runoff,
and nutrients);
B. To synthesize the existing large database and previous research results from
various Asian deltas, in order to upgrade the capability of geo-hazard assessment
for all delta systems;
C. To understand the role that geological processes and delta response play
in the proper assessment of global-change and human-modification impacts, including:
(a) sea-level rise associated with global warming, (b) land subsidence due to
groundwater withdrawal, (c) flooding from both drainage-basin runoff and coastal
storm surge, and (d) saltwater intrusion, river-channel dry-up and coastal erosion
due to upstream damming and water diversion;
D. To directly communicate the important issues and findings of the proposed
study with our policy- makers for adjusting the currently oversimplified manner
of hazard assessment, mitigation, and prevention. To establish an effective
network system among our delta-coastal scientists, aiming at a long-term collaboration
on the basis of information circulation;
E. To set up a Website for circulating the information of the project, in order
to call for more public awareness.
Workplan and Timeline
Synthesizing conceptual model
Key members of the project who have worked with different Asian mega-deltas
will work on the synthesis of conceptual delta models, and the risk assessment
of delta system during the year of 2003 and 2004, on the basis of large existing
database. This will present a substantial output to all participants during
the two workshops of 2004.
Expected Outcomes
l A long-term collaborative network among our delta scientists will be established
to work together for delta key issues;
l A web-site for proposed project will be set up to circulate information and
discuss key issues among our coastal scientists, as well as solicit public comments;
l Workshop proceedings and model results will be published to upgrade our academic
values, emphasizing the needs for a geological framework for assessing impacts
and hazards for representative delta systems;
l The criteria of hazard assessment will be standardized in terms of a series
of tables and maps.