Sari Johanna Väisänen

• Master of Science
• Researcher at Finnish Environment Institute

River networks are among Earth’s most threatened hot-spots of biodiversity and provide key ecosystem services (e.g., supply drinking water and food, climate regulation) essential to sustaining human well-being. Climate change and increased human water use are causing more rivers and streams to dry, with devastating impacts on biodiversity and ecosy...

Conventional dredging of ditches and streams to ensure agricultural drainage and flood mitigation can have severe environmental impacts. The aim of this paper is to investigate the potential benefits of an alternative, nature-based two-stage channel (TSC) design with floodplains excavated along the main channel. Through a literature survey, investi...

Science-informed, reductionist policy has systematically failed to address wicked situations. Such situations are highly interconnected and unpredictable. As a consequence, the implementation of so-called desirable interventions can lead to the export of vulnerabilities within and across different societal domains, sectors, intersections and scales...

Agriculture and forestry activities increase the deposition of fine sediments in river and streambeds, with negative consequences for biodiversity and stream ecosystem functioning. However, little is known about the economic value of headwater stream restoration and the associated improvement in ecosystem services. Here, we apply the contingent val...

The European Union Water Framework Directive (WFD) has created a demand for comparing the benefits and costs of the remedial measures. A major part of the benefits from improved water quality relate to the increased recreational value. However, there is a lack of easily operative and widely applicable quantitative methods to assess the benefits of...

Approximately 12,000 people live in the flood risk areas in Finland. New flood risk management plans were prepared for 21 areas as a part of the EU Floods Directive in 2015. In connection with this work, we conducted a survey in three flood risk areas in 2014. The total number of recipients was 4,710 and the response rate 39%. The study provided an...

Approximately 12,000 people live in the flood risk areas in Finland. New flood risk management plans were prepared for 21 areas as a part of the EU Floods Directive in 2015. In connection with this work, we conducted a survey in three flood risk areas in 2014. The total number of recipients was 4,710 and the response rate 39%. The study provided an...

The worldwide economic downturn and the climate change in the beginning of 21st century have stressed the need for cost efficient and systematic operations model for the monitoring and management of surface waters. However, these processes are still all too fragmented and incapable to respond these challenges. For example in Finland, the estimation...

The European Union's Water Framework Directive requires that all water bodies should achieve good ecological status at latest by 2027. A spreadsheet tool was developed to identify cost-effective solutions at a catchment scale in Finland. The tool is designed to meet the needs of regional river basin management planning in Finland. It can be used to...

Forest streams are important biodiversity hotspots and they influence the water quality of downstream water bodies. However, the condition of many Finnish forest streams has deteriorated due to forest drainage and consequent sedimentation. Restoration is a key component in freshwater management programs, in which the involvement and commitment of l...

1990-luvun loppuvuosilta saakka todettu leutojen ja sateisten talvien toistuminen saattaa olla ensimmäisiä maataloutta koskevia konkreettisia seurauksia ilmastonmuutoksesta. Sen vaikutusten arviointi maatalouden aiheuttamaan vesistökuormitukseen on keskeinen tehtävä jo ennen kuin ilmasto muuttuu pysyvästi erilaiseksi. Tämän tutkimuksen tavoitteena...