1423 / 2024-09-26 23:57:40

Assessment of Pacific Oyster (Crassostrea gigas) Marine Aquaculture Suitability in Shandong Offshore Area under the Climate Change

Pacific oyster,suitability assessment,GIS,Remote Sensing,ENSO,climate change

The Pacific oyster (Crassostrea gigas) is an important aquaculture species, with production experiencing rapid growth since the 1990s. In 2021, China accounted for nearly 90% of global production by 2021, reached 5.8377 million tons, with Shandong Province being the highest producer in China. The continuously expanding Pacific oyster marine aquaculture faces challenges such as high density and overcapacity, resulting in reduced water exchange capacity, biological accumulation, sedimentation, and diminished ecological carrying capacity. These issues weaken the offshore aquaculture system's ability to respond to climate change, making it more vulnerable to global climate events like the El Niño-Southern Oscillation (ENSO) and regional extreme weather. This study constructed a suitability assessment model for Pacific oyster farming based on satellite remote sensing, reanalysis data, and Geographic Information Systems (GIS) , considering water quality, hydrology, climatic conditions, and socioeconomic factors. The research delineated the temporal and spatial distribution of suitability in main Pacific oyster marine aquaculture regions along the Shandong offshore area. Additionally, the study utilized maximum entropy modeling and Pearson correlation analysis of time series data to explore the characteristics and mechanisms of current climate events and future climate change impacts. The results indicated that the inner bays of Shandong offshore area exhibited very high suitability, while outer areas show lower suitability with significant seasonal variability. The spatial and temporal distribution of suitability aligns with the actual conditions of existing Pacific oyster mairne aquaculture regions. ENSO induced precipitation anomalies lead to fluctuations in chlorophyll-a(Chl-a) and total suspended sediment(TSS) concentrations, affecting suitability. Overall, suitability is projected to increase under future climate scenarios, with high suitability areas expanding seaward; however, suitability may decline during the historical long-term period (2070-2100) under the 5-85 (SSP5-85) scenario. Finally, management recommendations were provided, including monitoring abnormal rainfall, implementing long-term intensive aquaculture in stable high-suitability areas, developing multi-site relay and multi-trophic integrated aquaculture in unstable high-suitability areas, and promoting offshore aquaculture initiatives.