Detection and Statistics of Offshore Aquaculture Rafts in Coastal Waters

Abstract

Offshore aquaculture is critical for a marine fishery economy. The spatial distribution of aquaculture that characterizes it plays a vital role in the sustainable development of marine resources and the protection of the marine environment. In recent years, China’s aquaculture has developed rapidly; specifically, the scale of aquaculture has dramatically expanded, and large-scale aquaculture has gradually grown in popularity. Although high-resolution satellite data can accurately extract aquaculture areas, the extraction of a large area of the sea area requires a copious amount of data. In contrast, medium-resolution satellite images allow for the extraction of aquaculture areas from large sea areas with a smaller amount of data, offering significant advantages. Therefore, we used Landsat8 satellite data to extract and count the number of aquaculture rafts based on the Hough transform and Canny edge detection methods. We tested the accuracy of this method by selecting Haizhou Bay as the study area for the experiment and accuracy verification and found that the automatic extraction accuracy for the number of aquaculture rafts was more than 90%. Additionally, we calculated statistics on the number of aquaculture rafts in Haizhou Bay over the past seven years. The findings presented in this paper offer a significant reference value for local marine utilization, marine environment protection, and marine disaster prevention and mitigation.

Marine Infrastructure Detection with Satellite Data—A Review

“…Thresholding methods [14,29,30,36,74,102,107] and Constant False Alarm Rate (CFAR) [17,38,95,96,101,104,106] are predominantly used here. Edge detection was used six times for detection [37,46,48,58,63,89]. These were followed by Reflection and Backscattering mechanisms with five applications [70,93,98,105,107], Visual Interpretation with four [70,93,110,112], and Band Operations with two [110,111].…”

“…OWFs were investigated six times from 2020 on Concentrating on thematic foci, aquaculture was investigated in 57 publications and was therefore the most commonly studied infrastructure type in this review. Raft aquaculture was the most studied (46%) [31,32,37,39,46,50,[55][56][57][58][59][60][61][62][63][64][65][66][67][68][69][70][71][72][73] and 12% of aquaculture studies looked specifically at cages [40,52,[74][75][76][77]. The remaining 42% investigated different types of aquaculture including raft, cage or longline in combination [33][34][35][47][48][49]53,54,[78][79][80][81][82][83][84][85][86]…”

“…The zoomed-in map (Figure 8) of East and Southeast Asia clearly shows that aquaculture is being studied along the entire Chinese coast. The hotspots here are Sansha Bay in Fujian Province (16 studies) [33][34][35]37,47,49,56,65,69,73,76,80,83,85,86,88], the offshore area around Dalian in Liaoning Province (13 studies) [37,39,49,50,53,[57][58][59][60]62,67,68,73], and Haizhou Bay in Jiangsu Province (9 studies) [31,32,55,61,63,66,[71][72][73]. Further site and local studies of aquaculture were carried out on the coast of Japan [59,70,93,106], on the south coast of South Korea [81,82], the south coast of Vietnam [43,…”

Intelligent Detection of Marine Offshore Aquaculture with High-Resolution Optical Remote Sensing Images

“…With massive quantities of remote sensing data accumulated every year, artificial intelligence is required to meet the increasing demand for food and the expansion of offshore aquaculture [12]. Machine learning (ML) techniques, including support vector machines, decision trees, random forest, and genetic programming, have been utilized in offshore aquaculture monitoring [7,13,14]. ML has great robustness in handling large or complex feature spaces [15] and can obtain reliable classification accuracy even without feature selection.…”

Investigating the Mechanism of Low-Salinity Environmental Adaptation in Sepia esculenta Larvae through Transcriptome Profiling

“…For aquaculture, a stable and suitable marine environment can facilitate the development of the aquaculture industry [1,2]. Global warming has led to accelerated glacier melting in recent years [3,4].…”