Spatial and temporal drought vulnerability of Norway spruce and Scots pine forests as a basis for forest decision support
We used the Swedish National Forest Inventory (SNFI) data to identify the spatial and temporal patterns of drought vulnerability for Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) forests in Sweden.
Our purpose is to quantify an important component of long-term ecosystem stability that can be used for forest management and policy decisions. Accordingly, such information can be used to reduce risks of yield loss and insect damages for forest owners, but also for adaptation of forest management to climate change.
(1) Identify site factors that cause/modify the tree growth anomalies for Norway spruce and Scots pine
(2) Identify places with high drought vulnerability, i.e. locations with a high probability to suffer a growth anomaly caused by drought.
(3) Identify the role of forest management practices to cope/modify the tree growth anomalies from drought.
(4) Diagnose the species differences and temporal change on tree resilience to face drought events.
Our purpose is to quantify an important component of long-term ecosystem stability that can be used for forest management and policy decisions. Accordingly, such information can be used to reduce risks of yield loss and insect damages for forest owners, but also for adaptation of forest management to climate change.
(1) Identify site factors that cause/modify the tree growth anomalies for Norway spruce and Scots pine
(2) Identify places with high drought vulnerability, i.e. locations with a high probability to suffer a growth anomaly caused by drought.
(3) Identify the role of forest management practices to cope/modify the tree growth anomalies from drought.
(4) Diagnose the species differences and temporal change on tree resilience to face drought events.
Figures: Drought vulnerability map for Scots pine (top) and Norway spruce (above). Dark colors show the locations with high probability to suffer a growth anomaly caused by drought.
Conclusions
- The water availability during the growing season and the altitude reduce the probability to develop a growth anomaly due to drought for both species.
- Stand competition, total basal area, and basal area of Scots pine increase the drought probability for Scots pine and Norway spruce respectively.
- The drought vulnerability is extended throughout the eastern part of Sweden for both species, but it is accentuated in south Sweden for Norway spruce.
- Summer drought intensity and time-lapse from the last forest intervention (thinning) increase the probability to have a growth anomaly for Scots pine.
This project has received funding from SLU's Environmental Monitoring and Assessment programs Forest and Climate (April 2020) to Jorge Aldea and Magnus Löf.