Study On Fishery Biodiversity And Habitat Of The Yellow River Estuary And Its Adjacent Waters

The Yellow River enters the sea in Dongying City,Shandong Province.Its adjacent waters are rich in nutrients and are important spawning grounds,breeding grounds and feeding grounds for marine organisms.However,under the interference of human factors such as pollution and fishing,the Yellow River mouth area has generally experienced decline and decline in fishery resources.The tendency of marine organisms to be degraded and simplistic,and there is the possibility of habitat fragmentation and fragmentation.To this end,this article analyzes the fishery resource surveys of the Yellow River estuary and nearby waters in late April,early August,and late September 2019.The results show that the ecological conditions of the sea area have recovered,and the level of biodiversity has increased compared with previous years,but the lack of key species,the shortage of high-trophic organisms and the fragmentation of the habitat are still prominent,and the summer resources show a downward trend.The specific results are as follows:1 The survey collected 79 species of catches,including 46 species of fish,29 species of crustaceans,and 4 species of cephalopods,belonging to 14 orders,42 families and 67 genera.The habitat type is mainly benthic,and the suitable temperature type is warm temperature.Mainly.There were 4 dominant species in April,namely,mantis shrimp,lachtail goby,Jiao ’s tongue sole,and spine brown shrimp.The IRI index ranged from 1285.35 to 3,53.49.In August,there were 6dominant species,namely Spear The IRI index of tailed goby,mantis shrimp,Jiao’s tongue sole,Japanese squid,hawk claw shrimp and Japanese scorpion was between1078.65 and 5895.22;in September,there were 4 dominant species,namely,latimeria,The IRI index of eagle claw shrimp,Jiao’s tongue sole and Japanese scorpion is between 1416.20 and 6111.73.Among them,Sacred goby and Jiao’s tongue sole are the dominant species throughout the year,both of which are small benthic warm-temperate fishes.Compared with historical data,the dominant species has clearly shifted to low-quality fishery resources.2.This article estimates that the number of fishery resources is 15,400 in April,151,700 in August,and 109,600 in September;the weight of the estimated fishery resources is 104.05 kg in April,871.90 kg in August,and 1194.76 kg in September.Among them,the number of fishery resources in April was the lowest in April,reached the highest in August,and fell in September;while the weight of fishery resources was the lowest in April,rose sharply in August,and continued to increase in September.Small benthic warm-temperate organisms occupy the main body,and the main production areas of fishery resources are the northwest and east waters of the Yellow River mouth.3.The data of the three surveys in 2019 showed that the total amount of fishery resources in the sea area for three months was 78117.52 t,of which 4,056.97 t in April,33,802.60 t in August,and 40,317.95 t in September;there are 6 types of important fishery resources in the three surveys.,Including short octopus,Jiao’s tongue sole,scallop crab,sacred goby,Japanese squid,Japanese scorpion,of which short scorpion,Japanese squid and Japanese scorpion are important economic species.4.The biological diversity related indexes of the sea area showed large fluctuations.Among them,the biological diversity index and uniformity index in April were higher than the historical data,the uniformity index in August was the same as the historical data,and the biological diversity index was low In the same period in previous years.Judging from historical data,the biodiversity and evenness in April were significantly higher than in previous years.The uniformity index in August was basically the same as in 2013,and the diversity index decreased significantly,while the types of fishery resources did not decrease but increased instead.This reflects the relatively low weight of fishery resources.5.Fishery habitats can be divided into 5 groups in April,4 groups in August,and5 groups in September.There are obvious differences between the groups,and the degree of continuity has a decreasing trend over time.In April,the distribution of fishery habitat groups was relatively continuous,with a higher proportion of high-productivity habitats;in August,the distribution of fishery habitats from the periphery of the Yellow River mouth to the southern part of Laizhou Bay was more consistent and regular,while the northern and northwestern parts were relatively scattered;September fishery The dispersion of habitats has intensified,and the degree of fragmentation has increased significantly.This is mainly reflected in the obvious difference between fishery habitats and the reduction of similarity between groups.At the same time,the spatial distribution of fishery habitat groups is scattered,basically belonging to the state of interval distribution,and there is no continuous distribution in large areas.