渤海夏季海水pH值年际时空变化

 收集渤海断面1978~2010年历年8月海水pH值、海水温度和大连站8月降水量观测资料,结果表明渤海夏季海水pH值年际变化范围为7.86~8.30,尚在适宜水生物生长的范围.采用EOF和最大熵谱分析,渤海夏季表底层海水pH值年际时空变化主要有两种模态,第一模态空间分量是断面南北海域同位相变化,时间分量周期为5.3a;第二模态空间分量是断面南北海域反位相变化,时间分量周期为3.2~10.7a.渤海夏季水温5a左右年际周期变化是影响夏季海水pH值年际变化的主要因素.历年8月降水量(酸雨)和月均黄河口径流量年际周期变化是影响夏季海水pH值年际变化的次要因素.渤海夏季断面海水pH值年际变化并不是规则的周期变化,其他因素也可以影响夏季海水pH值年际变化.

The interannual temporal-spatial variability of sea water pH in summer, Bohai Sea

The cross-section data of sea water pH, sea water temperature and rainfall in August in Dalian station of the Bohai Sea were collected over the years from 1978 to 2010. Results showed interannual variability in ocean pH of Bohai Sea in summer was in range of 7.86~8.30. It was suitable for the growth of aquatic organisms. According to results of EOF and maximum entropy spectral analysis, ocean pH interannual temporal-spatial variability of Bohai Sea in summer was in two major modes. The first mode was a cross-section of north-south sea area spatial components with phase change, and temporal component period was 5.3a.The spatial component of the second mode was anti-phase cross-section of north-south sea area change, with temporal component period 3.2~10.7a. It was the main factor that the five years sea water temperature changes around the Bohai Sea in summer affected the interannual cycle of summer interannual variability of sea water pH. It was the secondary factors that precipitation in August (acid rain) and the average monthly flow of the Yellow River impacted inerannual variability of sea water pH in summer.The cross-section of interannual variability in ocean pH in the Bohai Sea in summer was not the disciplinary cycle, other factors could also affect the summer interannual variation in ocean pH.