Benthic Disturbance and Impact Experiments in the Central Indian Ocean Basin
Benthic Disturbance and Impact Experiments in the Central Indian Ocean Basin
复制标题
中印度洋海盆的底栖扰动和冲击实验
DOI：
10.1080/10641190009353789
复制
发表时间：
2000
期刊：
影响因子：
--
通讯作者：
G. Walker
中科院分区：
文献类型：
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作者：
Rahul Sharma;B. Nagendernath;A. B. Valsangkar;G. Parthiban;K. M. Sivakolundu;G. Walker
摘要 作为结核采矿环境影响评估研究的一部分，中印度盆地启动了一项长期计划。根据该计划第一阶段收集的基线数据，在选定的区域进行了地质、生物、物理和化学参数的多学科研究。之前在太平洋进行的实验中也使用了液压装置来模拟海底扰动。通过流化泵和抽吸泵的组合反复扰动一个 3,000 × 200 m 的场地，将海底沉积物移出并排放到距海底 5 m 的水柱中。在9天的运营期间，进行了26次拖运，持续47小时的扰动，沿88公里的线路重新悬浮了约6,000立方米的沉积物。扰动后影响评估的数据是通过沉积物捕集器、深拖相机、海底样本和电导率-温度深度传感器（CTD）花环观测收集的。海底数据、沉积物样本和水柱研究旨在根据实验期间收集的扰动前和扰动后数据来评估底栖扰动的影响。观测表明，由于羽流迁移，沉积物的垂直混合以及横向移动和再沉积改变了各种参数，导致该地区周围环境的变化。
Abstract As a part of the Environmental Impact Assessment studies for nodule mining, a long-term program has been initiated in the Central Indian Basin. Multidisciplinary studies on geological, biological, physical, and chemical parameters were carried out in an area selected on the basis of baseline data collected in the first phase of the program. A benthic disturbance was simulated with a hydraulic device also used in the previous experiments in the Pacific Ocean. A site of 3,000 × 200 m was repeatedly disturbed by a combination of fluidizing pump and suction pump to dislodge and discharge sediment from the seafloor into the water column 5 m above the seafloor. During 9 days of operation, 26 tows were carried out for 47 h of disturbance, resuspending about 6,000 m3 of sediment along an 88-km line. Data for postdisturbance impact assessment were collected with sediment traps, deep-towed cameras, seafloor samples, and conductivity-temperature depth sensor (CTD)-rosette observations. Seafloor data, sediment samples, and water column studies were aimed at evaluating the impact of benthic disturbance, on the basis of pre- and post-disturbance data collected during the experiment. Observations show that vertical mixing of sediment as well as its lateral movement and resedimentation because of plume migration alters various parameters and leads to changes in the environment around the area.