| The proliferation of fishery resources is an important part of the conservation of aquatic living resources.The rational distribution of proliferation and release is the basis for the proliferation of fishery resources.The establishment of marine pasture demonstration areas is supplemented by proliferation and release.Sea otter is a kind of fishery species that is quick to supplement,strong in recovery and has great potential for proliferation.In the context of the increasingly severe destruction of the marine environment and the declining marine fishery resources,marine proliferation and release is an effective method to quickly supplement fishery resources.Therefore,the proliferation and release has great practical and research significance for the conservation of marine fishery resources.In this paper,the proliferation and release of sea bream was taken as the research object.Through the survey results from 2010 to 2019,the contribution of the proliferation and release of the southern peninsula to the sea otter resources,the impact on the change of sea otter resources,the impact on biodiversity and the control of the ecological niche of the sea otter were studied.The role of carbon sink fisheries and the impact on fishermen’s increase in production and income.The results are as follows:1.Through the background investigation and follow-up investigation,study the contribution of sea bream proliferation and release to Begonia resources.Among them,from 2010 to 2018,the contribution rate of sea otter resources to the sea otter resources in the southern Shandong Peninsula was between 94.18% and 99.87%,and the average resource contribution rate reached 96.70%.The resource contribution rate was relatively stable in each year.The survey results show that the sea otter fishing group is mainly a proliferation and release group,and the proliferation and release group plays an important role in supplementing the sea otter resources in the southern part of the Shandong Peninsula.From 2017 to 2018,the contribution rate of sea bream proliferation and release resources is lower than the average of the past 9 years,which is the lowest in the past 9years.The natural population of sea otters has reached the maximum,and the proportion of natural populations is increasing from the overall trend,indicating the proliferation and release of the past nine years.It has played a certain role in the restoration of natural resources of sea otters.It plays a positive role in the restoration of marine fishery resources in the southern part of Shandong Peninsula.2.Through the relative quantity survey over the years,assess the impact of sea bream proliferation and release on resource changes.In 2019,the amount of sea otter resources in the sea area of proliferation and release is mainly concentrated in Haiyang,Laiyang and other sea areas where the sea otter is proliferated and released.The relative weight distribution of sea otters in the discharged sea area accounts for 84.85%,while the proportion of undischarged sea area is only 15.15%.The distribution of relative resources in the sea area accounted for 78.48%,and the undischarged sea area accounted for 21.52%.In the assessment of resource quantity,the proliferation and release of sea bream fishery resources is significant,which plays an important role in the restoration of fishery resources.The number of political releases in 2010-2017 was basically the same,and the number of releases in 2018 was the lowest in 2019,while the relative weight density in2010-2012 showed an upward trend,while the relative weight density in 2013-2015 showed a downward trend.At the lowest level,the relative weight density in 2016-2018 is on the rise,reaching the maximum level in 2018,the lowest level in 2019,and the relative weight density is the average in the past 10 years.According to the data of near-bottom trawl survey in the southern part of Shandong Peninsula in 2010-2018,the spatial and temporal distribution of catch species composition and catch biomass were analyzed,and the dominance of catch species and Shannon-Wiener species diversity index were analyzed.(H’),richness index(D)and uniformity index(J’).The catches of each year are composed of fish,shrimps,crabs and cephalopods.The species of fish are decreasing year by year,and the shrimps,crabs and cephalopods have not changed much during the year.The relative resources of the survey period have certain volatility,which basically shows the current situation of low resource,uneven distribution and decreasing year by year.The relative resources are relatively high in Jiaozhou Bay,Dingziwankou and the southern part of Shidao.Two-way analysis of variance showed that there was a significant difference in the relative resources(F=12.657,P=0.0001),and there was no significant difference in space(F=0.959,P=0.541).During the survey year,there were five dominant species in the catch resources.The species richness index was 1.03~1.83,the species diversity index was 1.01~1.67,and the species uniformity index was 0.39~0.57.Bivariate correlation analysis showed that there was a certain correlation between H’ and D during the year,which was significantly correlated(P=0.035<0.05),while H’ and D(P=0.100)and H’ and J’(P=0.502).There are bigdifferences and there is no correlation.The summer swimming animal clustering results showed that the swimming animal community structure was similar in summer in 2014,2016,2015 and 2018,and showed similarity in other years.The offshore fishery resources structure in the southern part of Shandong Peninsula is relatively stable,and the resource level basically shows a trend of low resource resources,uneven distribution and decreasing year by year,and the resource level of miniaturized and low-valued catch species is high,and the fishery resource structure is high.Health needs to be improved.4.The content of carbon,nitrogen and phosphorus removed from the catching sea otter is subtracted from the input of carbon,nitrogen and phosphorus in the discharged pup,and the carbon,nitrogen and phosphorus content removed from the sea area is estimated.In 2017,the cumulative production of the seawater in the southern part of the Shandong Peninsula will be returned to the sea otter 11819.24.t,cumulative removal of carbon378.22 t in the sea,118.19 t of nitrogen,23.64 t of phosphorus,cumulative production of12,618.51 tons of sea otters in 2018,cumulative removal of 403.79 tons of carbon in the sea,126.18 tons of nitrogen,25.24 tons of phosphorus to mitigate climate change and Eliminating eutrophication in the offshore and bay is of positive significance.The proliferation and release of sea otters not only played a positive role in the replenishment and restoration of natural resources,but also benefited the majority of fishermen,effectively promoting fishermen’s increased production and income,increasing fishermen’s production and employment opportunities,and promoting coastal economic and social stability. |
