The challenge of monitoring impacts of water abstraction on macroinvertebrate assemblages in unregulated streams.

摘要: Monitoring of the ecological impacts water abstraction from unregulated streams in state New South Wales (NSW), Australia, is challenging because abstracted by thousands geographically dispersed users who pump intermittently according to temporally varying needs and limitations imposed licences access rules. Detailed, quantitative monitoring methods are too costly for widespread routine application size (801 000 km2) large number affected abstraction. We therefore tested possibility detecting on aquatic macroinvertebrates with rapid biological assessment (RBA) similar those that routinely used Australian rivers. sampled 85 sites north-eastern NSW during a period prolonged recurring drought, 54 which were designated as reference respect upstream entitlement was less than 1% their mean annual flow (MAF). The remaining, non-reference had an average 4% MAF licensed (range 1–20%). Sweep kick samples collected at each site two seasons, invertebrates picked 30 min per sample analysed genus level. found small but statistically significant overall difference macroinvertebrate assemblages between sites, amount did not affect degree individual deviated site-specific conditions. attribute absence evident impact mainly low proportions streamflow abstracted, RBA may also be factor. recommend risk-based approach future whereby effort focussed where high proportion abstracted. Copyright © 2009 John Wiley & Sons, Ltd.