Japan Geoscience Union Meeting 2018

Presentation information

[EE] Oral

A (Atmospheric and Hydrospheric Sciences) » A-HW Hydrology & Water Environment

[A-HW20] Materials transport and nutrient cycles in watersheds; Human and climate impacts

Sun. May 20, 2018 1:45 PM - 3:15 PM 105 (1F International Conference Hall, Makuhari Messe)

convener:Mitsuyo Saito(Graduate School of Environmental and Life Science, Okayama University), Shin-ichi Onodera(Graduate School of Integrated and Arts Sciences, Hiroshima University), Takahiro Hosono(熊本大学大学院先導機構, 共同), Adina Paytan(University of California Santa Cruz), Chairperson:Saito Mitsuyo(Graduate School of Environmental and Life Science, Okayama University)

2:55 PM - 3:15 PM

[AHW20-05] Reconstruction of environmental changes and anthropogenic activities based on sedimentary records in the Pearl River Delta, China

★Invited Papers

*Jianyao CHEN1, Lei GAO1, Zhiping YE1, Hongping Zeng1 (1.Sun Yastsen University)

Keywords:reconstruction, environmental change, Pearl River Delta, human activities, sediment

Rapid urbanization has occurred in the Pearl River Delta (PRD) since 1980s, resulting in tremendous accumulation of population and material in an area of around 4.0x104 km2. Massive nutrients, heavy metals and organic compounds were released to the coastal zone either via the Pearl River or the aquifer, and effects of these materials and possibly the re-suspension of the sediment on ecosystem and drinking water supply are a big public concern. Field campaigns to collect water samples and sediment from reservoir, river, delta plain, and estuary were implemented in rainy (April- September) and/or dry seasons (October – March) during the period of 2011-2017, and sediment from each layer of 1-2 m to a depth of 30-50 cm was collected. Samples were analyzed for major ions, nutrients, multiple isotopes(13C and 15N), heavy metals and microbiological DNA, and 210Pb was used to date the age of the sediment with particle size and flooding events as correction factors. Temporal pattern of nutrients/heavy metals was built for the period of 30 to 40 years, when the PRD experienced the economic boom and suffered the serious environmental pollution. Main sources of pollutants and relevant accumulation mechanism were interpreted for varied research sites.