Suitability evaluation on marine ranching in Guangdong,South China

The ecological suitability of marine resources and environmental conditions for marine ranching in Guangdong,South China was evaluated.Niche theory was used to establish an ecological suitability evaluation model for marine ranching site selection,and suitability evaluation of marine ranching was conducted in.Results show that the ecological suitability index of marine ranching site selection was greater than 64.0 in 20 sites,including offshore Shantou Bay,offshore Zhanjiang Port,and Longdou Bay etc.,which are the priority areas for marine ranching.In other 13 sites,the ecological suitability index ranged between 8.0 and 32.0,including Houjiang Bay,Haimen Bay,and Jieshi Bay etc.,indicating the suitability for marine ranching.However,the ecological suitability index was 0 in Shantou Bay,Zhujiang(Pearl)River estuary,Huangmao Sea,Guanghai Bay,Zhanjiang Port,Qiongzhou Strait,and Anpu Port.These sites are thus unsuitable for marine ranching.This study provides a theoretical basis for site selection and planning of marine ranching in Guangdong Province.

Marine Ranching Engineering Collaborative Innovation from the Perspective of Ecological Environment

As a resource development model with both economic and ecological functions,the environmental friendliness of marine ranching products meets the environmental needs of consumers.However,the lack of technological innovation ability limits the development of marine ranching.Therefore,this research builds a marine ranching collaborative innovation system with multi-agent participation.Evolutionary game theory is used to analyze strategic choices of all parties and the conditions of system equilibrium,and numerical simulation is used to analyze the effect of relevant factors.This paper integrates the benefits from the improvement of environmental friendliness into the payoff matrix,and explains the significance of collaborative innovation to the development of marine ranching from the perspective of ecological environment.The results showed:the participation willingness of marine ranching enterprises is positively related to open innovation subject,while the participation willingness of the other two parties is negatively related to the government;The incentive effect of collaboration is negatively correlated with the government’s will,positively correlated with the other two parties;The incentive effect of government subsidies positively affects the willingness of the three parties to participate.Finally,suggestions are provided for each participant to maintain the strategic choice of marine ranching collaborative innovation system.

Maximum sustainable yield estimation of enhancement species with the characteristics of movement inside and outside marine ranching

Marine ranching can be regarded as a type of artificial fishery,and its construction aims at the sustainable utilisation of fishery resources.Therefore,the sustainable yield level of target species in marine ranching has become one of the concerns of stakeholders.The enhancement surplus production model proposed by Wang(2021)based on the traditional surplus production model can be used to assess the sustainable utilisation of settled species in marine ranches.However,when the target species has the characteristics of migration inside and outside marine ranches,its sustainability assessment will be aff ected.Based on the movement range and resource density levels of enhancement species inside and outside marine ranches,we built a biomass change model that is suitable for enhancement species with migration characteristics inside and outside marine ranches(migration enhancement biomass model).Moreover,we simulated the effects of factors,such as the ratio of the movement range and the ratio of resource density within and outside marine ranches and the fishing strategy for the enhancement species in marine ranches,on the estimation of maximum sustainable yield(MSY).Results show that the large movement range of enhancement species outside marine ranches was associated with the obvious advantage of the proposed migration enhancement model over the traditional enhancement production model.A small difference in the densities of enhancement species inside and outside marine ranches was highly beneficial for improving the accuracy of MSY estimation.The migration enhancement biomass model proposed in this study provides an idea for estimating the MSY of an enhancement species that migrates inside and outside marine ranches.Researchers can adjust the parameters of the model in accordance with the actual situation of resource distribution and changes to improve the scientificity of fishery stock assessment.

Current Situation, Problems and Countermeasures of Marine Ranching Development in Guangdong Province, China

Combining the literature review and marine field investigation in the sea area,this article summarized the development and current situation of marine ranching at home and abroad.It analyzed the construction process of artificial fish reefs,proliferation and release,and national-level marine ranching demonstration areas,as well as the current development situation and existing problems of marine ranching-related industries in Guangdong Province.Guangdong has built 50 ecological artificial reef areas,3 large-scale artificial reef demonstration areas,1 local artificial reef area and 15 national marine ranching areas,with a total sea area of 1499.68 km^(2),and 2.004 million m^(3) of reefs.However,there are some problems in Guangdong marine ranching,including imperfect management mechanism,inconsistence in development concept and understanding,unclear rights and responsibilities in using sea area,lack of construction technology standards and specifications,low scientific and technological level and limited industrial development.In view of these problems,this article came up with countermeasures,including insisting on ecology-prioritized development,and strengthening the coordination of multiple departments;creating a management mode conducive to market-oriented operation;breaking through the issue of sea area ownership;establishing a technical standard system for marine ranch construction in Guangdong;strengthening the research on the basis of high-quality construction and key common technologies of Guangdong marine ranching;establishing industrialization modes of Guangdong marine ranching according to local conditions.Understanding the development status of marine ranching in Guangdong and exploring the development strategies of marine ranching industry by referring to the relevant experience at home and abroad can provide references for the effective management,efficient and sustainable development of marine ranching in Guangdong and the integration of three industries in the development of marine ranching in Guangdong.

The suitability assessment on site selection for bottom seeding scallop culture based on analytic hierarchy process

Scallop culture is an important way of bottom-seeding marine ranching,which is of great significance to improve the current situation of fishery resources.However,there are some problems in site-selection evaluation of marine ranching,such as imperfect criteria system,complex structure,untargeted criteria quantification,etc.In addition,no site-selection evaluation method of bottom-seeding culture areas for scallops is available.Therefore,we established a hierarchy structure model according to the analytic hierarchy process(AHP)theory,in which social,physical,chemical,and biological environments are used as main criteria,and marine functional zonation,water depth,current,water temperature,salinity,substrate type,water quality,sediment quality,red tide,phytoplankton,and zooplankton are used as sub-criteria,on which a multi-parameter evaluation system is set up.Meanwhile,the dualism method,assignment method,and membership function method were used to quantify sub-criteria,and a quantitative evaluation for the entire criteria was added,including the evaluation and analysis of two types of unsuitable environmental situations.By overall consideration in scallop yield,quality,and marine ranching construction objectives,the weight of the main criteria could be determined.Five grades in the suitability corresponding to the evaluation result were divided,and the Python language was used to create an evaluation system for efficient calculation and intuitive presentation of the evaluation outcome.Eight marine cases were simulated based on existing survey data,and the results prove that the method is feasible for evaluating and analyzing the site selection of bottom-seeding culture areas for scallops under various environmental situations.The proposed evaluation method can be promoted for the site selection of bottom-seeding marine ranching.This study provided theoretical and methodological references for the site selection evaluation of other types of marine ranching.

Pre and Post Effects Assessment of Marine Ranch Construction in Chlorophyll-a Concentration Using MODIS Data and a Web-Based Tool. A Case Study in Zhelin Bay, China

Chlorophyll-a (Chl-a) concentration in lakes can tell a lot about a lake’s water quality and ecosystem. It is a measure of the amount of algae growing in a waterbody and can be used to monitor the trophic condition of a waterbody. We studied the pre and post effects of marine ranch construction in Chl-a concentration in Zhelin Bay, Southern China using Normalized Difference Chlorophyll Index (NDCI) and a web-based tool (https://mapcoordinates.info/). We used 8 day composite MODIS image collections of 500 m resolution and randomly selected two stations to extract the chlorophyll-a concentration values through the web-based tool. We recorded the slight increase in NDCI values in all stations after the construction of marine ranch which is a good indicator of the marine organisms’ reproduction and survival.

Research Advances in Hydrodynamics of Artificial Reef

With further recession and deterioration of offshore fishery resources and increasing living demands, construction of marine ranching becomes a focal point to improve marine biological resources and environment, while artificial reef is one of the important parts for marine ranching construction. The artificial reef technology develops slowly in China compared with developed countries, such as the United States and Japan, and there are still many issues urgently to be solved. When an artificial reef is released in water, there are various kinds of forces, and its forces and flow field-effect are closely related to surrounding conditions and its own performance. Currently, there are no mature conclusions on research of hydrodynamics of artificial reef. According to review of hydrodynamics of artificial reefs, we hope to give a full understanding on hydrodynamics performance of artificial reefs, and provide reference and theoretical basis for further research on design and structure of artificial reef in China.

Spatiotemporal dynamics of coastal aquaculture and driving force analysis in Southeastern China

Introduction:Large-scale disordered coastal aquaculture development causes severe environmental problems.However,quantitative assessments of spatiotemporal dynamics and driving factors for coastal aquaculture are essential and urgent for coastal aquaculture sustainability.Outcomes:Using remote sensing products and geographic information science,we investigated the long-term landscape changes due to coastal aquaculture,and explored its underlying driving factors in the Ningde coastal region,Southeastern China.Results show that coastal aquaculture area increased from 90.65 km2 in 2003 to 96.08 km^(2) in 2016,and its structure underwent tremendous changes.The area of artificial shrimp ponds increased by 496.15%and the area of farmland ponds decreased by 25.81%between 2003 and 2016.In addition,we revealed that from 2003 to 2016,the change trends of the coastal aquaculture area and the entire Ningde coastal region were consistent,and became more fragmented and dispersive.Furthermore,regression results indicate that the growth and attenuation of coastal aquaculture areas were significantly affected by the initial coastal aquaculture area in 2003.Discussion and Conclusion:To sustainably manage the coastal ecosystems,we provide several recommendations(e.g.,a coupled human and natural systems approach to understanding human-nature interactions,integrated assessment,and systematical spatial planning and monitoring)for future research and management.