Extreme cold events reduce the stability of mangrove soil mollusc community biomass in the context of climate impact

Abstract

Abstract The frequency and intensity of climate extreme events are expected to increase with global warming in the future. Climate extreme events, such as an extreme cold event (ECE) will continue to influence the stability of soil fauna community biomass, since climate changes often cause a shift in community compositions and structures (e.g. biomass). Few studies, however, have addressed the effects of climate extreme events on the stability of soil fauna community biomass. A field investigation was conducted from 2007 to 2010 to assess the influence of an ECE on the biomass stability of the soil mollusc community across four mangrove wetlands (∼450 km) in South China. Distance-decay and time-decay were used to test the spatiotemporal dynamics of the community biomass. Network analysis and null model were performed to detect the importance of competitive interactions in shaping the stability of the soil mollusc community biomass. The ECE reduced the biomass of the soil mollusc community but increased the complexity of the spatiotemporal patterns of the community biomass. The ECE increased divergent temporal succession and spatial segregation in the soil mollusc community biomass, reflecting the spatiotemporal dynamics of the soil mollusc community biomass influenced by the ECE. Importantly, the ECE decreased the biomass stability of the soil mollusc community by an average of 34.17%. An increase in the modularity of an interactive network (by 75%) and a rise in the intensity of species competition were found after the ECE, reflecting that the ECE enhanced the competitive interactions of the soil mollusc community. The changes in the biomass stability of the soil mollusc community potentially impact their ability to provide ecosystem functions and services such as food production and carbon sequestration for humans. In general, these findings provide valuable ecological insights concerning the effects of climate extremes on the stability properties of ecological soil communities, thereby providing potential applications for soil management and predicting climate changes.