Challenges and opportunities for implementing nature-based solutions for disaster risk reduction in mountainous Central Asia

Abstract

Implementing nature-based solutions (NbS) in mountainous Central Asia involves numerous challenges given the diverse hazards and harsh climates. Three regional examples of different challenges for NbS are presented: (1) Gunt River valley in the Pamir of Tajikistan; (2) Fergana valley, southwest Kyrgyzstan; and (3) northern Tien Shan in Kyrgyzstan. In Gunt valley, a major challenge for NbS is the extensive development of farms and settlements on vulnerable debris fans. Of the 49 fans mapped in the steep-sided valley, 34 were assessed as unstable, all of which were developed; 63 % of the fans received snow avalanche deposits. Tree planting in key areas of fans to reduce the spread of debris flows is a viable NbS. Widespread conversion of native fruit and nut forests to overgrazed pastures in the hilly terrain of Fergana valley together with fissures created during nearby earthquakes has increased the occurrence of damaging landslides/debris flows in deep loess deposits. Restoring deep-rooted native woody vegetation together with reducing grazing pressure in these hills can be effective NbS. Frequent debris flows and episodic glacial lake outburst floods (GLOFs) have occurred during heavy rainfall throughout the Kungey and Kungey Ala-Too Ranges in northern Tien Shan. Here, because of the powerful force of these disasters, only limited opportunities for NbS exist – e.g., planting woody shrubs along outer edges of deflection dams for stabilization. Early-warning systems are needed in the most vulnerable areas to reduce hazard risk. These three examples show that NbS must be designed based on local conditions to be effective.