Abstract

NASA’s Suomi National Polar-orbiting Partnership (NPP), Visible Infra-red Imaging Radiometer Suite (VIIRS) data utilized to detect night time lights (NTL) radiances and fishing boat pixels using VIIRS boat detection (VBD) approach. Study attempted for first time in Indian waters to detect night time fishing boats during 2017 along with chlorophyll and sea surface temperature (SST). Night-time fishing observed higher in Arabian Sea (AS) compared to Bay of Bengal (BoB). The reason likely the shallower bathymetry (50–200meters) of AS, broader continental shelf and more biological productivity, compared to BoB’s narrow and steep continental slope and less productive water. AS night time fishery observed season-dependent (December–May) with VBD pixels ranging 100–300, wherein BoB distribution is sparse, <30 VBD pixels. In AS, moderate/high chlorophyll (0.2–1.2 mgm⁻³), moderate SST (27–30.5 °C) and non-cloudy months observed suitable for night time fishing. In BoB, moderate chlorophyll (0.2-0.45 mgm⁻³) and moderate SST (27-30.5 °C) played positive role for night light fishing.

摘要

NASA 的 Suomi 国家极地轨道合作伙伴关系 (NPP)、可见红外成像辐射计套件 (VIIRS) 数据用于使用 VIIRS 船检测 (VBD) 方法检测夜间灯光 (NTL) 辐射和渔船像素。研究首次尝试在印度水域检测 2017 年的夜间渔船以及叶绿素和海面温度 (SST)。与孟加拉湾 (BoB) 相比，阿拉伯海 (AS) 的夜间捕鱼量更高。与 BoB 狭窄陡峭的大陆坡和低产水相比，原因可能是 AS 的水深较浅（50-200 米）、大陆架更宽、生物生产力更高。AS 夜间渔业观察到与季节有关（12 月至 5 月），VBD 像素范围为 100-300，其中 BoB 分布稀疏，<30 VBD 像素。在 AS 中，⁻³ )、中等 SST (27–30.5 °C) 和非多云月份观察到适合夜间捕鱼。在 BoB 中，适度的叶绿素 (0.2-0.45 mgm ^-3 ) 和适度的 SST (27-30.5 °C) 对夜间光钓起积极作用。