Forest Management Part Forest Management Part Forest Management Part Forest Management Part

It's all about forest management

1. Hans Pretzsch
Sustainable Forest Management
1 History: Hard way from exploitation to management
2Forests in Germany at present. A short overview
3Concept for sustainable forest ecosystem management
4Models as tools for sustainable forest management
5Model application at the stand and landscape level
Pretzsch,H.(2009):ForestDynamics,GrowthandYield.Springer,Berlin,664p.

2. 1 History: Hard way from exploitation to management
2Forests in Germany at present. A short overview
3Concept for sustainable forest ecosystem management
4Models as tools for sustainable forest management
5Model application at the stand and landscape level
Hans Pretzsch
Sustainable Forest Management

3. Frankfurt
Latitude: N 50‘
(Sachalin, Blagoveschensk,
Prague, Winnipeg, Vancouver)
Longitude: E 10‘
(Oslo, Tunis, Gabun)
Total area: 36 x 10
6
ha
Forest area11 x 10
6
ha
Net primaryproductivityof
forests(NPP):
1.0-1.5 kg m
2
yr
-1
,
10-15 t ha
-1
yr
-1
(Biomass)
East-West-extension of
mountainchains
40 %

6. The Romans starteda firstdreadfulclearingwavein our
forestsin the1st –3rd Century...

7. ... but the forests recovered in 4th –5th Century as a
result of the Romans retreat and Germanic migrations.

8. Population explosionin theMiddleAges (12th-13th C.)
triggereda reductionof forestcoverageto< 30 % ...

9. ... followed by a recovery of the forests due to the
pestilence and Thirty Years‘ War (14th-17th Century)

10. Industrialization in 18th and 19th century:
Wood for mining, smelting, house building etc.

11. From scenarios to decision support

12. Carl von Carlowitz 1713 „Sylvicultura
Oeconomica“ pp. 428
Instructions for sustainable cultivation
of forests
coal as substitute
for wood
Sustainable management, decrees, and coal mining
relieved forests from exploitation in 18th –19th Century

13. World War II damagestheforests: Arms industry,
devastationbywar damage, clearingforreparations...

14. ... afforestations mainly with Norway spruce and
Scots pine recovered standing volume and growth

15. Long-term consequences of clearing, exploitation and
devastation caused by World War II

16. Neerdar, Sauerland, 1959

17. Norway spruce stands damaged by bark beetle
Rachel und Lusen,Bavarian Forest, 2010

18. Storm damage by Gudrun
>75 million m
3
Småland,
Schweden, 2005

19. __________________________________________________________________________________
Mixing proportions (>10 % stand area) according to inventories GRI 1971, BWI I 1987, BWI 2 2002,
BWI 3 2014 in Bavaria
Idea of close-to-nature
forestry
Back to complex mixed-species forests.
From the idea to realization in Bavaria
1920 1930-40 1976 1990 2010
Möller
1920
v. Keudell
1932/35
47 %
66 %
73 %
Idea of „Dauerwald“
% mixed stands
Krutzsch, Wobst
1950
Increasing calamities,
climate change,
Extended forest functions
and services

20. •Fourterrible wavesofforestdevastation:
Invasion oftheRomans 1st -3rd C.,
Population explosionin theMiddleAges,
Industrialization14th-17th C., and
World war II
•In spiteofthosewavesofforestdevastationextendedwooded
regionsanda forestcovering> 30 % weresaved.
•Transition fromartificialmonoculturestoclose-to-nature
mixed-speciesforest.
•Forestmanagersandscientistsareappreciatedbysociety.
Résumé 1