Evolution of Chemical Environment in Jiaozhou Bay published
Src:QNLM     14:33:12 08/23/2016

Recently, Evolution of Chemical Environment in Jiaozhou Bay, a book of 600,000 characters funded by QNLM's "Aoshan Talent"for Excellent scientists, was published and circulated by China Science Publishing and Media Ltd. The book was mainly compiled by Song Jinming, research fellow of QNLM Functional Lab for Marine Ecosystem and Environment Science. Based on the materials from a number of surveys aboard, the book falls into 22 chapters of seawater, sediment and inflow into Jiaozhou Bay. It elaborates and systematically brings to light the evolution process, current situation and trend of the chemical environment in Jiaozhou Bay in terms of current status of research, evolution trend, inflow of substance, change of seawater environment and evolution of sediment. The publishing of the book serves as an important guide to further revealing the changing process of Jiaozhou Bay and utilizing it in a scientific way.

Known as the Mother Bay of Qingdao, Jiaozhou Bay is fed by Dagu River and Nanjiao River. The mouth of the Bay is surrounded by Qingdao Port (Four Port Areas of Old Qingdao Port, Huangdao Oil Port, New Qianwan Port and Dongjiakou Port). Distributed along the Bay counterclockwise are Shinan District, Shibei District, Licang District, Chengyang District, Jiaozhou City and Huangdao District (Development Zone). The change of the environment in Jiaozhou Bay is mainly caused by human factors and natural changes. The leading factors for the change of the environment are land reclamation and ocean engineering offshore. According to the report in 1935, the total tidal water storage capacity of Jiaozhou Bay was 1.18 billion m3, and the biggest speed of surface current was 1.8 m/sec. In 1985, the total tidal water storage capacity was 910 million m3, and the biggest speed of surface current was 1.2 m/sec. In 2008 and 2014, the total tidal water storage capacity was 850 million m3 and 760 million m3 respectively. The total tidal water storage capacity declined considerably in the past decades, showing clearly the dramatic change in the environment of Jiaozhou Bay. The important discoveries from this research are as follows. 1. Dramatic changes happened in three stages in the past 100 years: change of the natural background---strong effect of human factors on environment---apparent improvement. The situation remained relatively stable  from the early 20th century to 1970s. Since 1980s, the human activities, especially the fast industrial and agricultural development around the Bay resulted in worse and worse eutrophication of the seawater. Closely associated with the eutrophication, the biogenic element was on the rise in its burial fluxes, especially from mid 1990s to the late 20th century.

In the early 21st century, the control of the pollution around the Bay somewhat reduced the eutrophication of the Bay, leading to the remarkable reduction in the burial fluxes of biogenic element and dramatic improvement of the Bay ecosystem. 2. It was discovered that the key reason that limits the phytoplankton in the Bay is the transfer of water body silicon to the sediment. Currently, the N/P ratio of Jiaozhou Bay is declining while S/N ratio is rising --- a clear changing trend for the integration of Jiaozou Bay water body and sediment environment. 3. It was discovered that suaeda heteroptera, most adaptive plant in the coastal wetland of Jiaozhou Bay, has become considerably dependent on the element transfer from heavy to light in the atomic numbers, in the sediment of the coastal wetland, happening in all parts of the plant from roots to leaves. That may lead to the fractional distillation of the light and heavy elements, and will have a significant impact on the substances brought into Jiaozhou Bay and on the ecosystem of Jiaozhou Bay.