You cannot step twice into the same river: the transformation of Central European temperate forest communities over the past century Radim Hédl, Markéta Chudomelová, Martin Kopecký, Martin Macek, Vladan Riedl, Péter Szabó, Jan Šipoš, Ondřej Vild
„You cannot step twice into the same river“ (in a place of an ecological theory, 2500 years old) Παντα θει – Everything is flux (Heraclitus)
Studying vegetation dynamics • focus on temporal changes • focus on variation between sites • carefully make some generalizations
fauxphilnews.wordpress.com/ 2012/10/17/heraclitus-2012/
Recent environmental changes - habitat fragmentation and loss - changed nutrient balance (surplus of N, acidification) - climate change - biotic invasions etc. Biodiversity decline - decreasing local diversity - biotic homogenization - decreasing functional diversity etc. But really?
No net change in species richness resurveys of vegetation plots (usually after several decades) Vellend et al., 2013, PNAS 5-261 years’ resurveys
Bernhardt-Römermann et al., 2015, GCB 17-75 years’ resurveys
Generally nutrient-richer, shadier forests resurveys, indirect estimation
Ellenberg N
Verheyen et al., 2012, JEcology
Ellenberg L
» soil » climate » topography » herbivory » competition » forest management
change
Biodiversity in temperate forests: focus on the herbaceous vegetation
time
2015
The past forest management Historical forest database for Moravia (E-Czech Republic) MS Access, 4 historians entering all possible archival data on forest species composition, management etc. www.longwood.cz
Fagus and Picea distribution 11th--19th century archival data Moravia (E-Czech Rep.) 28,000 km2 Source: historical forest database, www.longwood.cz
Past forest management Coppicing, 19th century Moravia (E-Czech Rep.) 28,000 km2 Source: historical forest database, www.longwood.cz
Past forest management Coppicing, 18th century Moravia (E-Czech Rep.) 28,000 km2 Source: historical forest database, www.longwood.cz
Coincidence of the 19thc. coppicing and occurrence of species groups Group Asarum europaeum
Group Geranium sanguineum
Significant factors: - altitude - mollisols - acidic cambisols NOT coppicing
Significant factors: + coppicing -altitude NOT soils
Moravia, E-Czech Republic, 28,000 km2
Re-survey of forest vegetation plots in the Czech Republic • potentially ca. 50 thousand „historical“ plots 1930s–1980 • resampling started in the early 1990s • mostly forestry typology survey (1950s–present) Semi-permanent plots (approximate location by map, coordinates etc.) • Database of resurveyed forest plots www.longwood.cz 1953
2004
Distribution of plot altitudes 1000
altitude (m asl.)
Current analysis • 15 localities • 1806 samples / 903 plots • old samples 1953-1978 • resampling 2002-2014 • altitude 165-950 m asl. • plot size 400–500 m2
800 600 400 200 0 0
200
400
600
included other
800
1000
Change between the surveys • 15 localities, 1806 samples • 1953–2014 • altitude 165-950 m asl.
species richness Boří les
lowland
Hodonínská Dúbrava Bzenecká Dúbrava Kapánsko Polabí Milovický les Krumlovský les Ždánický les
upland
Děvín Chřiby Středohoří-Lovosice Středohoří-Litoměřice Bílé Karpaty Rychlebské hory
highland
Velká Javořina -30
-20
-10
0
10
20
30
40
No. species per plot (mean, SD)
Change between the surveys • 15 localities, 1806 samples • 1953–2014 • altitude 165-950 m asl.
EIV nutrients Boří les
lowland
Hodonínská Dúbrava Bzenecká Dúbrava Kapánsko Polabí Milovický les Krumlovský les Ždánický les
upland
Děvín Chřiby Středohoří-Lovosice Středohoří-Litoměřice Bílé Karpaty Rychlebské hory
highland
Velká Javořina -3
-2
-1
0
1
2
3
Plot-wise change (mean, SD)
Change between the surveys • 15 localities, 1806 samples • 1953–2014 • altitude 165-950 m asl.
EIV light Boří les
lowland
Hodonínská Dúbrava Bzenecká Dúbrava Kapánsko Polabí Milovický les Krumlovský les Ždánický les
upland
Děvín Chřiby Středohoří-Lovosice Středohoří-Litoměřice Bílé Karpaty Rychlebské hory
highland
Velká Javořina -3
-2
-1
0
1
2
3
Plot-wise change (mean, SD)
Change between the surveys • 15 localities, 1806 samples • 1953–2014 • altitude 165-950 m asl.
EIV moisture Boří les
lowland
Hodonínská Dúbrava Bzenecká Dúbrava Kapánsko Polabí Milovický les Krumlovský les Ždánický les
upland
Děvín Chřiby Středohoří-Lovosice Středohoří-Litoměřice Bílé Karpaty Rychlebské hory
highland
Velká Javořina -3
-2
-1
0
1
2
3
Plot-wise change (mean, SD)
Change between the surveys • 15 localities, 1806 • 1953–2014 • altitude 165-950 m asl.
Beta-diversity old survey new survey
mean dissimilarity
„Sensitive“ species Uncommon but sensitively indicating long-term environmental changes 16 spp.
15 spp.
5 spp.
y-axis: % of all occurrences in old or new surveys note the scaling differences images source: commons.wikimedia.com
Invasive species: focus on Impatiens
Other possibly important factors: - soil texture / moisture - disturbances
Conclusions • Species diversity consistent with the existing studies, no net change in species richness. • Invasive species increased, orchids and wintergreens decreased. • Environmental changes consistent with previous studies (nutrients, light, moisture). • No pattern along altitude/forest management was observed.
Ongoing research: getting more detailed explanatory data • plot/site–wise data on management history • better data on abiotic environment (soil, light, deposition etc.) • inclusion of species traits
Historical management as explanatory factor For each (re)survey period • management form • tree species composition • forest stand age • intensity of the most recent cutting • stand density / tree volume • non-forestry uses • game density and composition Two periods: - medieval to 1850 - 1850 to present
Creating a historical-ecological database of resurveyed forest plots Management, level 1: prehistoric to 1850
Management, level 2: 1950–present
Environmental influences: deposition, temperature…
Thank you The research leading to these results has received funding from the European Research Council under the European Union’s Seventh Framework Programme (FP7/2007-2013) / ERC Grant agreement no 278065.
www.longwood.cz
