A study quantifies the dual impacts of climate change and land use on global riverine fish communities. Climate change and land use endanger the biodiversity of global river ecosystems, but the combined effects of these phenomena have not been well characterized. Lise Comte, Xingli Giam, and colleagues analyzed 12,517 species abundance time-series spanning 10-68 years from monitoring programs and research projects covering 951 riverine fish species to quantify changes in fish community composition over time. The authors measured the species' average affinities for both water temperature and streamflow. Overall, 52.3% of the time-series showed an increasing dominance of warm water species over time and 51.3% showed an increasing dominance of species preferring slow water flows. However, community trajectories showed considerable variation and were uncorrelated at the global scale. Communities with less initial diversity and higher intrinsic sensitivity showed the highest rate of species reorganization, especially in response to temperature changes. The results also showed that land use has synergistic interactions with temperature changes, given that increases in warm-water species were higher in river systems with more human modification. According to the authors, the complex interactions between climate change and land use suggest the need for further study to produce accurate predictions and guidance for river conservation as global temperatures continue to increase.
###
Article #2020-11639 "Climate and land-use changes interact to drive long-term reorganization of riverine fish communities globally," by Lise Comte, Julian D. Olden, Pablo A. Tedesco, Albert Ruhi, and Xingli Giam.
MEDIA CONTACTS: Lise Comte, Illinois State University, Normal, IL; tel: 2068864738; email: < lccomte@ilstu.edu >; Xingli Giam, University of Tennessee, Knoxville, TN; tel: 609 751 4871; email: < xgiam@utk.edu >
Proceedings of the National Academy of Sciences