Exploring the Role of Weather and Forest Management on Nutrient Export in Boreal Forested Catchments Using Spatially Distributed Model

Weather-driven hydrological variability and forest management influence the nutrient export from terrestrial to aquatic systems. We quantified effect range of variation in total nitrogen phosphorus Vehka-Kuonanjärvi catchment located southeastern Finland. A distributed model NutSpaFHy was used with varying weather scenarios (compiled observed extreme years dry, wet & mild) (including no additional intensive clear-cutting all mature stands existing structure). Nutrient exports by scenario combinations were compared modeled baseline weather. The results showed that increase mild (over 55%) exceeded caused (23 %). Dry decreased tenth baseline, which per hectare 2.22 kg for N, 0.08 P). suggest future maintaining a good ecological status systems can be challenging if winters occur more frequently. Certain characteristics, e.g., deciduous tree percentage, open area percentage site fertility, induced Hotspot analysis enabled identifying areas currently high This helps targeting water protection efficiently.