Evaluation of fish resources in Qingcaosha Reservoir based on dual-frequency identification sonar technology

Abstract:

The main fish resources of Qingcaosha Reservoir were detected and evaluated by dual-frequency identification sonar (DIDSON) in September, 2015. The data collected by DIDSON are analyzed and processed by Fishery Acoustic Data Processing Software Echoview. The fish in the image is counted and the accuracy of software counting is verified by the artificial visual counting. The amount of major fish stocks in the reservoir was further evaluated based on the number of fish collected by DIDSON and the information on the fish length and weight of fish collected by the catch. The results show that the number of reservoir fish is about 1.16×10⁷～1.24 ×10⁷, and the proportion of small fish (length <20 cm) is 78.3%, while the medium and large fish (length> 40 cm) accounted for a small proportion (8.5%). From the relationship between the average body weight and body weight in the reservoir area,it can be concluded that the reservoir fishery resource is about 4 620～4 980 t. The spatial distribution of fish body weight in reservoirs was given by GIS method. The spatial distribution of fish weight in the route was analyzed by GIS. The results showed that there were more resources in the deep-water region on the southeast side of the reservoir, while the resources on the northwest side of the reservoir were generally less. The innovative applicability of DIDSON in assessing fishery resources of Qingcaosha Reservoir is discussed, and some suggestions and prospects are put forward.