Quantifying effective restoration: reassessing the productive capacity of a constructed stream 14 years after construction

Published source details Scrimgeour G.J., Tonn W.M. & Jones N.E. (2014) Quantifying effective restoration: reassessing the productive capacity of a constructed stream 14 years after construction. Canadian Journal of Fisheries and Aquatic Sciences, 71, 589-601.
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Summary

Action: Excavate new river channel

A paired, site comparison study in 1998–2011 of seven Arctic streams in the Northwest Territories, Canada (Scrimgeour et al. 2014) found that a created stream supported a lower abundance of macrophytes and algae/mosses growing on rocks than nearby natural streams, 14 years after creation. Compared to the natural streams, the created stream had lower cover of macrophytes in both pools (created: 1%: natural: 28%) and riffles (created: <1%; natural: 10%). The created stream also supported a lower biomass (ash free dry mass) of algae/mosses growing on rocks, in both pools (created: 0.3: natural: 2.4 mg/cm²) and riffles (created: 0.3; natural: 4.1 mg/cm²). Results were similar 1–3 years after stream creation (see original paper, and compare Jones et al. 2008). Methods: In 1997, a new 3.4-km-long stream channel was excavated. The stream bypassed two existing lakes and streams that were destroyed to mine diamonds. Vegetation was surveyed in the created stream and five nearby natural streams each July 1998–2000, and again in July 2011. Cover of macrophytes (excluding bryophytes) was visually estimated in 0.1-m²quadrats. Algae and mosses were scraped from rock surfaces. Surveys included both pools and riffles (2). This study used the same stream, and some of the same reference streams, as Jones et al. 2008.