A biodiversity metric for assessing the ecological status of New Zealand rivers
Holistic, ecosystem-based approaches to river management are now required that go beyond the physical parameters of water quantity and quality. Because fish integrate the multitude of factors affecting river ecosystems at a range of scales and over long time periods, the overall status of the fish community reflects a river‘s life supporting capacity and its ecological integrity. But as fish distributions vary widely within rivers, metrics for fish community status are required at a river basin scale. Moreover, the metrics must be robust, easily quantified, understandable and relevant. SIFR (Status Index for Fish in Rivers) is based on the overall frequency distribution for the number of species recorded per site within a river basin. Values for 82 New Zealand rivers ranged from a low of 1.29 to a high of 4.81, with a mean of 2.87. Low values (<2.5) characterised degraded rivers whereas the least modified rivers had high values (> 4.0). Although, this metric is sensitive to the main physical stressors known to affect native fish in New Zealand rivers (e.g., migration barriers, pollution, habitat degradation), it is also sensitive to biotic stressors, notably the impact of introduced fish. As such, it provides a means of comparing the capacity of rivers to support intact food-webs and can be used to monitor the ecological status of river basins over decadal periods.
river restoration fish communities fish species occurrence biodiversity trout impact
D.K.Rowe
National Institute of Water and Atmospheric Research, PO Box 11-115, Hamilton, New Zealand
国际会议
The 3rd Biennial ISRS Symposium Achieving Healthy and Viable Rivers (ISRS)第3届国际河流大会
北京
英文
456-464
2013-08-05（万方平台首次上网日期，不代表论文的发表时间）