Instructions for querying results from NFI plots
Attention! Due to a calculation error, we had to correct the figures for biomass and growing stock in living trees. The corrections affect NFI5 and the changes NFI4–NFI5. The corrected data was uploaded on September 9th, 2024.
More information
Despite established control mechanisms, an error has occurred in the formula for importing tree height measurements (on tariff sample trees) from NFI5. Only the status in NFI5 and the changes in the period LFI4-LFI5 are affected by this error, all previous inventories are not.
This error resulted in a de facto rounding off of the tree height to the full metre. The biomass and the growing stock of living trees in NFI5 are affected. Therefore, the increment between NFI4-NFI5 is also affected, but the mortality and cut in this period is not. As a result, the calculated growing stock, biomass and increment of the NFI interim results LFI5.1-5 were calculated too low. The NFI results are corrected, which affects 11,700 of the 160,000 published NFI result tables on LFI.ch.
For Switzerland as a whole, the stock and biomass were underestimated by approx. 1%. For gross increment, the figure is up to 6% higher. The cut-to-growth ratio was overestimated by 7 percentage points. The deviation of 1% for stock corresponds to the simple standard error of the estimate and is therefore rather small in its significance. The deviation in increment and the cut-to-increment ratio, on the other hand, is in a range that can be relevant for forestry.
A total of 169,015 tables and maps with NFI results are currently available for selection in the interactive results query system.
All tables follow the structure shown below.
The ‘target variable’ is the topic being analysed (e.g. forest area, growing stock, number of stems); the ‘classification variable’ is used to classify the analysed data (target variable) according to a certain characteristic (e.g. ownership, with the classes public and private); and the ‘regional demarcation’ is used to classify the data geographically (e.g. production regions, cantons).
The maps are based on the tables, with each table row visualised separately.
You can use keywords of your choice to start a results query (‘search’). Alternatively, you can select the target variable from a list (‘topics’), specify the regional demarcation (‘regions’), or select the NFI (‘inventories’) for which you would like to see results.
Current version of data: NFI5.1–5 (2018–2022)
All results, including those from previous inventories, are recalculated using the methods currently in use to ensure the comparability of data from different inventories. Results published in previous reports therefore may not be identical to the latest values posted online.
Citation
Abegg, M.; Ahles, P.; Allgaier Leuch, B.; Cioldi, F.; Didion, M.; Düggelin, C.; Fischer, C.; Herold, A.; Meile, R.; Rohner, B.; Rösler, E.; Speich, S.; Temperli, C.; Traub, B.,
2023: Swiss national forest inventory NFI. Result tables and maps of the NFI surveys 1983–2022 (NFI1, NFI2, NFI3, NFI4, NFI5.1–5) on the internet. [Published online 30.05.2023] Available from the World Wide Web <http://www.lfi.ch/resultate/> . Birmensdorf, Swiss Federal Research Institute WSL
https://doi.org/10.21258/1769925