斯里兰卡近海海洋生态环境变化遥感监测分析

Remote Sensing Monitoring and Variation Analysis of Marine Ecological Environment in Coastal Waters of Sri Lanka

斯里兰卡是海上丝绸之路沿线重要的节点国家,其周边海域生态环境变化与经济发展、休闲生活和食品安全密切相关。利用2002—2017年的MODIS遥感反演产品对斯里兰卡岛周边海域、关键节点港口科伦坡的生态环境参数年际变化规律分别进行分析和2003—2012年的MERIS遥感反射率产品对保克海峡进行水体类型时空分析,结论如下:①研究区内光合作用有效辐射高值出现在马纳尔湾,海域沿岸浮游植物生物量相对较高,与海表温度负相关,外海浮游植物生物量极低,与透明度负相关。②科伦坡港附近水温(海表温度)、海面光照强度(光合作用有效辐射)、水体清洁度(海水透明度)、海洋食物网基础的浮游植物生物量(叶绿素浓度)和浮游植物净初级生产力最大值分别出现在4月、3月、3月、8月、7月,致灾因素重点关注8月潜在的赤潮。③保克海峡浑浊带的源头是印度的卡里梅尔角,由高韦里河携带大量泥沙造成。这有助于了解和认识高时空变化的保克海峡及斯里兰卡周边海域在不同时间-空间的海洋生态环境。

Sri Lanka is an important node country along China’s Maritime Silk Road. The changes in the ecological environment of its surrounding sea areas are closely related to its economic development, leisure life and dietary safety. This study analyzed Sri Lanka’s surrounding waters and Colombo as a key node port from 2002 to 2017 using MODIS remote sensing products to characterize the interannual variations of ecological environment parameters. The MERIS remote sensing reflectance products were used to analyze the spatial and temporal characteristics of water bodies in the Palk Strait(2003-2012). Conclusions can be made as the following statements:(1) Within the study area, photosynthetically active radiation was observed higher value in Gulf of Mannar. The biomass of phytoplankton is relatively high in the coastal areas and inversely related to the sea surface temperature, while that in the open sea is extremely low and inversely related to seawater transparency.(2) In Colombo Port, the maximum values month of sea surface temperature, light intensity(photosynthetically active radiation), water cleanliness(seawater transparency), phytoplankton biomass and net primary phytoplankton productivity appear in April, March, March, August and July respectively, and the red tide, as a potential disaster causing factor, needs to be concerned in August.(3) The sources of the turbidity zone in the Palk Strait were the large amounts of sediment carried by the Cauvery River from Calimere cape of India.The distribution characteristics and long-term changing trends were analyzed, which provided a better understanding of the high temporal and spatial variations in the marine ecological environment of the Palk Strait and the surrounding waters of Sri Lanka in different time and space.