Exploring spatio-temporal heterogeneity and inter-domain ecological networks of biological community in a marine ranching habitat: Implications for fishery resources conservation

Habitat changes in marine ranching can cause variations in biological resources and community structure. However, the complex inter-domain ecological network (IDEN) in this particular habitat are not well understood. Thus, we employed field surveys and multivariate statistical analyses to explore the spatio-temporal heterogeneity and the IDEN of biological communities within a marine ranching in southern Yintan of Beihai City, China. Our findings indicated that seasonal succession and artificial reefs (ARs) deployment had simultaneous effects on both biotic and abiotic factors, and the former effect was more pronounced. Based on orthogonal partial least squares discriminant analysis (OPLS-DA), various biota (phytoplankton, zooplankton, and nekton) can be broadly categorized into four groups on seasonal and spatial scales. Variable importance projection (VIP) and redundancy analysis (RDA) demonstrated that autumn biomarkers such as Hemidiscus hardmannianus, Oikopleura rufescens, Lagocephalus lunaris were positively correlated with water temperature (WT), salinity (Sal) and inorganic nitrogen (IN), whereas spring biomarkers such as Rhizosolenia robusta, Euconchoecia aculeata, Penaeus penicillatus were positively correlated with dissolved (DO), chemical oxygen demand (COD), and inorganic phosphorus (IP). The IDEN analysis revealed that 23 species such as Chaetoceros densus, Centropages tenuiremis, and Parargyrops edita played a key role in maintaining the stability of the biological communities in the studied sea area. This study can provide novel insights and theoretical supports for the ecological effects analysis and species protection in marine ranching.