Related Experiment Video
Updated: Jun 18, 2026
12:50
Continuous Instream Monitoring of Nutrients and Sediment in Agricultural Watersheds
Published on: September 26, 2017
Forest harvest increases runoff most during low flows in two boreal streams
Rasmus Sørensen1, Eva Ring, Markus Meili
1Department of Aquatic Sciences and Assessment, SLU, Uppsala, Sweden. rasmus.sorensen@vatten.slu.se
Ambio
|December 1, 2009
Summary
Forest harvesting significantly increased runoff by 35% in Swedish catchments, especially during growing seasons and low flows. These hydrological changes, particularly altered base flows, may impact aquatic ecosystems.
Area of Science:
- Forestry and Hydrology
- Environmental Science
- Ecosystem Dynamics
Background:
- Understanding forest harvest impacts on aquatic environments requires analyzing hydrological regime shifts.
- Previous research highlights the link between forest management practices and water resource alterations.
Purpose of the Study:
- To quantify changes in the hydrological regime in harvested forest catchments during the initial two years post-harvest.
- To compare post-harvest hydrological responses against a reference catchment to isolate the effects of forest removal.
Main Methods:
- Utilized data from two harvested catchments and one reference catchment within the Balsjö Catchment Study in Sweden.
- Established a baseline hydrological regime through an 18-month pre-treatment calibration period.
- Monitored and analyzed runoff data for two years following forest harvest (August 2006 - March 2008).
Main Results:
- Harvested catchments exhibited an average of 35% greater runoff compared to the reference catchment.
- The most substantial flow increases were observed during growing seasons and at base flows (58-99% increase).
- Spring flood peak was delayed and attenuated post-harvest; no significant changes noted for highest flows (>5 mm d(-1)).
Conclusions:
- Forest harvesting demonstrably alters catchment hydrology, leading to increased overall runoff and base flows.
- Significant changes in low flow conditions post-harvest can substantially influence aquatic habitat availability and ecosystem function.
- Hydrological regime shifts following forest harvest necessitate careful consideration for water resource management and ecological conservation.
More Related Videos
Related Concept Videos
01:24Freshwater Microbial Ecology
Freshwater systems such as streams, rivers, and lakes exhibit distinct physical and biological characteristics that influence their microbial communities. These environments are broadly categorized into lotic systems—those with flowing waters like streams and most rivers—and lentic systems, which include still or slow-moving waters such as lakes, ponds, and marshes.In lentic systems, phytoplankton drive primary production, generating autochthonous organic carbon. In contrast, lotic systems...
02:41Responses to Drought and Flooding
Water plays a significant role in the life cycle of plants. However, insufficient or excess of water can be detrimental and pose a serious threat to plants.
01:50Threats to Biodiversity
There have been five major extinction events throughout geological history, resulting in the elimination of biodiversity, followed by a rebound of species that adapted to the new conditions. In the current geological epoch, the Holocene, there is a sixth extinction event in progress. This mass extinction has been attributed to human activities and is thus provisionally called the Anthropocene. In 2019 the human population reached 7.7 billion people and is projected to comprise 10 billion by...
01:30Underflow Gates
Underflow gates are vital for controlling water flow in irrigation canals. The three main types of underflow gates — vertical, radial, and drum gates — serve different purposes while ensuring effective flow management. Vertical gates move up and down, generating a free-flowing water jet; radial gates pivot to regulate the flow; and drum gates rotate for precise adjustments. The flow through these gates is influenced by downstream conditions, resulting in free or drowned outflow.Free and Drowned...
01:57Adaptations that Reduce Water Loss
Though evaporation from plant leaves drives transpiration, it also results in loss of water. Because water is critical for photosynthetic reactions and other cellular processes, evolutionary pressures on plants in different environments have driven the acquisition of adaptations that reduce water loss.
01:30Microbial Wastewater Treatment
Microbial communities in aquatic ecosystems play a key role in the natural breakdown of contaminants introduced through domestic and industrial effluents. Acting as biological catalysts, these microbes change and mineralize a wide range of organic and inorganic pollutants under different redox conditions.In oxygen-rich surface waters, aerobic heterotrophs lead organic matter breakdown, using oxygen as the terminal electron acceptor to efficiently oxidize substrates to carbon dioxide and water.