Freshwater biologists often seek to restore turbid shallow lakes dominated by phytoplankton to clear-water systems with a high abundance of submerged plants. The usual plan of operation, which is often guided by lake ecosystem modelling, is to reduce external inputs of nutrients (e.g., from agricultural runoff or urban waste streams) to a threshold level at […]
September 28, 2021
Comments Off on In-stream wood increases fish abundance
Although fallen woody material provides many freshwater fish species with essential habitat for feeding, refuge and spawning, a lot of submerged wood has been removed from rivers in an attempt to prevent floods and improve boat passage. However, current best management practice is to reverse this historical trend by reintroducing wood to rivers and streams. […]
September 28, 2021
Comments Off on Restoration of urban headwaters pays dividends
Because urban streams are often ecologically degraded as a result of channelisation and pollution, restoration work is often attempted to improve ecosystem structure and function. This usually involves remodelling of the stream channel. Knowing that there are predictable shifts in ecosystem processes between headwater streams and the main body of the river, American ecologists investigated […]
September 28, 2021
Comments Off on Assessing human impacts on river systems
Because many river systems have been significantly modified as a result of human activities, indicators of changing river structure and function are very helpful in guiding our efforts to manage rivers on a sustainable basis. A number of different indicators based on the hydrology, chemistry or biology of rivers have been developed, but in many […]
March 13, 2021
Comments Off on Aquatic ecosystem services: impacts of land use
Streams and riparian zones are seldom given priority in protected-area planning, and little is known about the effects of protection on the many ecosystem services that streams provide. To help fill this knowledge gap, researchers studied differences in biodiversity and the ecosystem services provided by 28 streams in protected and unprotected watersheds in Quebec, Canada. […]
March 13, 2021
Comments Off on Aquatic ecosystem services: rethinking streamside planting
Spatial patterns in the loss of natural land cover to agriculture have a significant effect on ecosystem services, including those provided by landscape features that interrupt runoff flows to rivers. For example, the number, size and location of woodland patches all have an impact on ecosystem services such as sediment trapping, pollutant retention and the […]
March 13, 2021
Comments Off on Restoring overheated rivers
One of the features of the so-called “urban stream syndrome” is thermal pollution caused by warm environments in built-up areas, which can increase stream temperatures above the tolerance threshold for aquatic organisms. The good news is that urban stream temperatures can be reduced by re-naturalisation measures designed to improve flood control, water quality and habitats. […]
December 14, 2021
Comments Off on Lake management: are tipping points real?