The species–area relationship for a highly fragmented temperate river system

Ecosphere

Peter C. Esselman¹  Beth L. Sparks‐Jackson¹  Leon M. Carl²  Chris C. Wilson³ 

[1] Great Lakes Science Center U.S. Geological Survey 1451 Green Road Ann Arbor Michigan48105USA;Midcontinent Region U.S. Geological Survey 1451 Green Road Ann Arbor Michigan48105USA;Ontario Ministry of Natural Resources and Forestry Trent University Symons Campus, 1600 West Bank Drive Peterborough OntarioK9J 7B8Canada;

关键词: area per se;    fish diversity;    fragmentation;    habitat;    species–area relationships;    Trent River;   

DOI  :  10.1002/ecs2.3411

来源: DOAJ

【 摘 要 】

Abstract Despite the importance of species–area relationships (SARs) to conservation, SARs in human‐fragmented rivers have received little attention. Our aim was to test for the presence and strength of SARs for littoral fish assemblages of an extensively dammed river in south‐central Ontario, Canada, and to examine long‐running hypotheses for the drivers of SARs. Twenty‐six navigational dams with locks built between 1837 and 1913 occur along the 160 km length of the Trent River examined in this study. We evaluated the relationship between richness and fragment area, and then used linear models to test whether the area per se, habitat diversity, or other hypotheses were best supported by the data. A power–function relationship with area explained 46% of the variation in fish species richness, and the slope (z = 0.4) was high compared with SARs reported from other ecosystems, indicating that species accumulated rapidly with an increase in fragment area. Multi‐predictor models suggested that area was significantly related to richness, but that vegetation cover diversity had a stronger relative effect. The slope of our SAR may indicate that there is a high degree of isolation between populations in different fragments, even though the lock system reportedly allows some passage of organisms. Our findings also suggest that mitigating against local extinction due to small population sizes (i.e., area effects), and enhancing aquatic vegetation cover may be viable strategies for promoting species diversity in the study river. Studies of SARs in fragmented rivers may offer additional benefits to supporting restoration planning where efforts are being made to increase species diversity.

【 授权许可】

Unknown