Austria’s forests affected by adverse climate conditions
Austrian Forest Inventory 2018-2023 shows effects of climate change and emphasises the importance of active forest management.
Austria is one of the most densely forested countries in Europe. Forests cover around 48% of the territory and provide a wide range of services for our society: they protect against natural hazards, provide recreation and ensure employment. Wood as a renewable resource and the derived wood products contribute significantly to climate protection and to the energy transition process. However, the changing climate conditions affect also our forests, as shown by the latest results of the Austrian Forest Inventory 2018/23.
Drought periods and extreme events occur more frequently
The recent years were characterised by exceptional climatic conditions. During periods of drought, trees reduce their growth resulting in a decline of wood increment in Austrian forests. More frequent disturbance events, such as windthrow and bark beetle infestation also lead to reduced wood increment, owing to larger quantities of damaged timber and subsequently to larger regeneration areas than planned. As a consequence, the observed trend over the recent decades towards more deciduous and mixed forests continues.
Forest area and standing stock stabilize at high levels
Since the beginning of the Austrian National Forest Inventory in the 1960s, forest area and standing stock have steadily increased and have reached a high level. The current forest area covers 4.02 million hectares, and the standing stock in productive forests has grown over this time period from 780 million cubic metres (m3) to 1,180 million m3. For the first time in recent years, the effects of climate change have become apparent through a slight decline in the standing stocks. According to the latest results of the Austrian National Forest Inventory 2018/23, the standing stock now amounts to 1,174 million m3 in the productive forests.
Additionally, the mean annual wood increment decreased from 29.2 million m3 to 28.2 million m3. Due to the climate change induced increase of forest disturbance events, the amount of harvested wood accounts for around 97 % of wood increment. Due to regional differences in disturbance events, the ratio between harvests and increment can also exceed 100 % in certain areas. Unsurprisingly, due to the changing climate conditions, similar situations can be observed in most European countries.
In addition, the productive forest stands, which are frequently located in accessible sites in the valleys and at gentle slopes, are managed more intensively than less productive stands at higher altitudes and steep slopes. As a result, the proportion of slower-growing old large-timber stands is increasing. The regeneration of these stands should be aimed for in the next decade to increase forest stability.
Forests are important for biodiversity
Through active forest management and forest conversion with suitable climate-resilient tree species, forest managers support the adaptation of forests to future climate conditions and the conservation of biodiverse forest ecosystems. Forest biodiversity is preserved and promoted by retaining old and large trees featuring microhabitats, maintaining wet and dry biotopes and leaving branch piles, stone runs and stone walls. Deadwood is a meaningful biodiversity indicator. Standing deadwood in the productive forests currently amounts to 10.5 m3/ha (3 % of the total standing stock), showing a notable increase from 9.7 m3/ha in the previous assessment. Thereby, the trend towards more deadwood in Austria’s forests which has been observed since the 1990s continues.
Relevance of reliable forest information
Gaining up-to-date, reliable and comprehensive data and knowledge on the status and changes of our forests is becoming increasingly important due to the current developments. The information needs range from conventional indicators, such as the ratio between wood increment and harvest, to conclusions on more complex topics such as biodiversity, bioeconomy or climate protection.
To meet the growing need for forest information and the requirements at national and international levels, the Austrian National Forest Inventory has begun to conduct annual surveys on one sixth of the sample grid since 2016. In total, more than 11,000 sample plots are surveyed and assessed by the forest inventory experts. This enables annual updates of the most important facts and figures results on the Austrian forest.
Outlook
We anticipate that the climate change related developments in our forests will persist with even more intensive impacts of drought, bark beetle and storm damage events. Overall, forest dynamics are accelerating due to climate change. Yet, the forest ecosystem, climate-friendly forest management and the resulting wood products remain crucial elements in mitigating climate change. This was already demonstrated by the CareforParis study led by the Federal Environment Agency , according to which wood and wood products can substitute and significantly reduce the use of fossil resources.
In view of the effects of climate change on our society, the reduction of greenhouse gas emissions to the atmosphere is the most effective and important lever for climate protection. Without a reduction of CO2 emissions, the forests are limited in their positive function in coping with the ongoing climate change. This is indicated by the latest results of the Austrian National Forest Inventory 2018/23, the most recent annual data update, which provides essential information needed to shape forest development.
Further information
The detailed results of the Austrian National Forest Inventory 2018/23 will be available by the end of February 2025 at www.waldinventur.at.
Contact
DI Christian Lackner, Public Relations, BFW
christian.lackner@bfw.gv.at, 0664/8412702