Research
| Title： | Impact of invasive apple snails on shallow water ecosystems under different nutrient conditions: results from a mesocosm study |
|---|---|
| First author： | He, Liang; Guo, Shiyuan; Wang, Guanghao; Ning, Zixuan; Zhang, Huan; Ge, Gang |
| Journal： | HYDROBIOLOGIA |
| Years： | 2024 |
| DOI： | 10.1007/s10750-024-05621-3 |
| Abstract： | The consequences of non-native species invasion may depend on the characteristics of the invaded ecosystem, such as abiotic environmental conditions and biological community structure. Invasive herbivores can have a substantial adverse impact on the abundance of submerged macrophytes and trigger declines in water quality. Although previous research has posited that shallow lakes with higher nutrient conditions might exhibit greater susceptibility to non-native herbivores, empirical support for this claim remains limited. In this study, we employed 24 mesocosms to simulate shallow water ecosystems, with the primary objective of assessing the influence of invasive herbivorous apple snails (Pomacea canaliculata) on submerged macrophyte and phytoplankton abundance under two distinct nutrient conditions. Our findings indicate that moderate nutrient enrichment alone promoted submerged macrophyte growth, leading to a 156% increase in total biomass in the nutrient-enriched treatment compared to the control (low-nutrient conditions without apple snails). However, the introduction of apple snails caused a significant reduction in submerged macrophyte biomass in both nutrient conditions, approximately 100% loss in low-nutrient conditions and a roughly 50% loss in moderately nutrient-enriched conditions. Additionally, the presence of apple snails slightly increased phytoplankton abundance (similar to 57 chl-a mu g/l for phytoplankton and similar to 2 mu g/l chl-a for cyanobacteria) under low-nutrient conditions, while triggering a shift to a turbid state dominated by planktonic algae (similar to 270 chl-a mu g/l for phytoplankton and similar to 36 mu g/l chl-a for cyanobacteria) under moderately nutrient-enriched conditions. These results emphasize the need for effective management strategies to control invasive herbivores and decrease nutrient inputs. |
