Table 1 Overview of the NFI datasets used and their most important features
From: Species-specific, pan-European diameter increment models based on data of 2.3 million trees
Country/Region | Inventory cycle | Inventory dates | Mean census interval (years) | Number of plots | Plot radius (m) | Diameter threshold (cm) | Comment | NTrees |
|---|---|---|---|---|---|---|---|---|
France | NFI5–6 | 2005–2012 | 5 (core of all trees on the plot) | 50,404 | 15 | 7.5 |  | 474,588 |
Germany | NFI1/NFI2 | 1986 − 1989/ 2000–2002 | 14.3 | 10,344 | angle count method |  | 137,425 | |
Germany | NFI2/NFI3 | 2002–2012 | 10.2 | 17,604 | angle count method |  | 272,034 | |
Italy - Piemonte |  | 1999–2004 | 10 (core from 1 tree per plot) | 13,192 | variable (8-15 m) | 7.5 | DBH rounded to cm | 13,192 |
Italy - Aosta |  | 1992–1994 | 10 (core from 1 tree per plot) | 1691 | variable (8-15 m) | 7.5 | DBH rounded to cm | 1691 |
Ireland | NFI1/NFI2 | 2004–2006/ 2009–2012 | 6.1 | 577 | 3/7/12.62 | 7/12/20 |  | 8859 |
Netherlands | NFI5/NFI6 | 2001–2005/ 2012–2013 | 9.5 | 1235 | variable (5–20 m) | 5 |  | 18,348 |
Norway | NFI9/NFI10 | 2004–2008/ 2009–2013 | 5 | 9243 | 8.92 | 5 |  | 201,484 |
Poland | NFI1/NFI2 | 2005–2009/ 2010–2014 | 5 | 17,488 | variable (7.98, 11.28 or 12.62) | 7 |  | 350,487 |
Spain | NFI2/NFI3 | 1986–1995/ 1996–2008 | 11.2 | 50,957 | 5/10/15/25 | 7.5/12.5/22.5/42.5 | 557,848 | |
Sweden | NFI7–8/NFI8–9 | 2005–2009/ 2010–2014 | 5 | 14,833 | 3.5/10 | 4/10 |  | 246,852 |
Switzerland | NFI2/NFI3 | 1993–1996/ 2004–2006 | 10.9 | 5217 | 8/12.6 (in flat terrain) | 12/36 | DBH rounded down to cm | 49,192 |
Total |  | 1986–2014 |  | 192,785 |  |  |  | 2,332,000 |