本文利用2003~2012年MODIS(Moderate Resolution Imaging Spectrometer)卫星遥感数据,分析了四十里湾叶绿素a浓度的时空分布特征,并探讨其影响机制。结果表明,四十里湾叶绿素a浓度具有显著的时空分布特征。从空间分布来看,全年均是南部近岸较高,从西南的湾内向东北的湾外逐渐降低。逛荡河口正北约6 km海域在4~5、7~9月出现叶绿素a高值羽。从时间分布来看,四十里湾叶绿素a浓度夏季最高,春秋次之,冬季最低,5月份和8月份出现峰值,呈现温带海域特有的"双峰"特性。四十里湾年平均叶绿素a浓度呈现波动状态,波动范围约为6~12 mg/m3。四十里湾叶绿素a浓度的分布及变化与海表面温度成正相关,相关系数是0.41。另外,入海排污和海水养殖业等人类活动可能也是影响四十里湾叶绿素a浓度时空变化的重要因素。
This study investigated the spatial-temporal distribution characteristics of chlorophyll a (chl-a) in Sishili Bay using MODIS satallite remote sensing data from 2003 to 2012,, and analyzed the relationship between chl-a distribution and influential factors. Results showed that the chl-a concentration in Sishili Bay had a significant spatial-temporal characteristics. The chl-a showed a decreased tendency from estuary to offshore. A plume appeared 6 km away from Guangdang River estuary in April, May, July, August and September. The highest value of chl-a appeared in summer, and the lowest in winter. The higher value appeared in May and August showed an obvious double-peak character. The relationship between chl-a and sea surface temperature was positive with a correlation coefficient of 0.41. The distribution of chl-a may also be related to the human activities, especially sewage and aquaculture.