Islamic Jamal al–Din zij and Chinese Shoushi-li(授時曆) are astronomical hand books compiled by Jamal al-Din(札馬 魯丁) and Guo Shujing(郭守敬) of the Islamic and Chinese Astronomical Bureau in Yuan(元) China, respectively. Jamal al-Din zij is an Islamic zij based on the Almagest of Ptolemaios, while Shoushii-li is a calendrical treatise by the traditional Chinese calendar system. In case of the parallax correction method, however, both of them have a common origin from Indian astronomy in 6-7 Century. This paper examines and discusses the parallax theory and its origin adopted in Jamal al–Din zij and Shoushi-li as following: 1) Definitions of the parallax theory and parallax correction methods. 2) Similarities and origins of the parallax correction methods adopted in the Jamal al–Din zij and Shoushi-li. 3) Comparison of the parallax correction tables included in the Sanjufini zij of Tibet, the Huihui-lifa(回回曆法) of Ming(明) China and the Chiljeongsan-Oepyeon(七政算外篇) of Joseon(朝鮮) Korea. 4) Routes of the parallax theory transmitted from ancient Greece and India to Joseon via Islam world and China, respectively. 5) Astronomical exchanges and mutual influence between the East and the West.

Gwangyang Bay, a semi-closed water channel, has habited various shellfish species and has been much influenced because of introduction from Sumjin River and sewage discharge from Gwangyang City, as well as enriched nutrients from industrial complex. We have determined the analysis of long-term monitoring data in water qualities including nutrients in Gwangyang Bay during 1987-2010, except for 1991, 1995, 1996, 1998, 2002 and 2003 of which these years do not enough water quality data to analysis in this study. In May, June, July, August, September and October were carried out the analysis of temperature, salinity, DO, transparency, SS, DIN, DIP, COD, Chl-a, and ocean climate. Temperature, salinity, DO, DIN, DIP, COD were analyzed in surface and bottom. These water parameters were showed in yearly fluctuations, in particular, salinity and DIN were a significant difference between surface and bottom based on One-way ANOVA because of intensive precipitation and irradiation in summer. However, the period of summer is the highest number of larvae in shellfish which possibly has increased their mortality because of osmotic pressure from freshwater. Higher SS and lower transparency were associated with decreasing the photosynthesis in phytoplankton, but higher Chl-a in this study was possibly contributed to more introduction of pico or nano-phytoplankton than that of commonsize phytoplankton. Consequently, it is necessary for long-term monitoring in Gwangyang Bay to produce a sustainable shellfish farming and maintain marine eco-system.

We examined the horizontal distribution of salinity and the concentrations of DIN and DIP after heavy rainfall events in coastal areas of South Korea from Yeoja Bay to Narodo and from Gwangyang Bay to Geomodo to determine whether fresh water actually flows into areas of Cochlodinium polykrikoides red tides and to observe its effect on the growth of this organism after heavy rainfall. Following heavy rainfall (155 mm) in the Yeosu and Suncheon regions, the average salinity was 21 and 29 psu at Yeoja Bay and in the coastal waters of Narodo, respectively. After 126 mm of rainfall, the values were 19 and 25 psu in the coastal waters of Yeosu and Geomodo, respectively. This may have been caused by an influx of fresh water, after the rainfall event, into the open sea coastal areas around Narodo and Geomodo from the Dong and Seomjin Rivers, which are about 3540 km away. After the rainfall, the concentrations of NH4-N, NO2-N, and PO4-P were slightly increased; however, the concentration of NO3-N was greatly increased and diffused throughout the coastal areas of Narodo and Geomodo, which frequently experience C. polykrikoides blooms. The influence of NH4-N, NO2-N, and PO4-P on the occurrence of C. polykrikoidesred tides in coastal areas around Narodo and Geomodo after heavy rainfall does not appear to be great. Instead, the occurrence C. polykrikoides red tides in the coastal areas of Narodo and Geomodo seems to be facilitated by NO3-N.