Modelling dynamics of soil organic matter under historical land-use management in European Russia

Transcription

1 Modelling dynamics of soil organic matter under historical land-use management in European Russia Maxim Bobrovsky, Alexander Komarov, Tatyana Kubasova, Alex Mikhailov Institute of Physicochemical and Biological Problems of Soil Sciences of Russian Academy of Science Pushchino (Russia)

2 Historical land-use impacts Felling Ploughing Slash-and-burn Litter harvesting Fire Grazing

3 Historical land-use impacts Stock-breeding Forest grazing prevailed Licevoj svod, XVI c. Moscow The Gospel, XI c. Paris Miniature, XVIII c. Moscow

4 Engraving by Kallo, France Historical land-use impacts Felling, brushwood harvesting Carpet, XI c.

5 Historical land-use impacts Branches, litter harvesting Mowing etc. Lekarstvo duschevnoe, XVII c. Moscow Derevenskoe zerkalo, 1798, Tula The important part of impacts was connected with historical agriculture systems

6 Traditional Pic. by Lindholm, XVIII c. Finland agriculture systems Slash-and-burn system Shifting agriculture (forest-shifting system) Licevoj svod, XVI c. Moscow Three-field system (type of fallow system)

7 Chronology of traditional agriculture systems for Central Russia Slash-and-burn system Fallow system (incl. three-field system) Field-forest shifting system????

8 All territory of Central European Russia was impacted by historical agriculture systems Typical landscapes of Central Eu.Russia Miniatures from Meyerberg Album, 1661

9 It is possible to estimate directly the short-term influence of different human impacts on natural ecosystems the total influence of detached human impacts in the past (burning, tillage, pasture, etc.) on present-day ecosystems It is impossible to estimate directly the long-term influence of human impacts on ecosystems

10 Objective To apply a computer model to estimate the long-term dynamics of soil organic matter (SOM) under the historical agriculture A. Verhoyatsky icon, detail. XVII c.

11 EFIMOD model of forest-soil dynamics PAR Climate Initialisation Available PAR for trees, ground vegetation and natural regeneration T R E E S n Ground vegetation Natural regeneration Redistribution of soil available nitrogen Model of soil organic matter ROMUL Forest manager Data viewer Graph interface 3D visualisation Komarov et al., 2003, Ecol.Mod.

12 Land-use management scenarios for three agricultural systems 1. Slash-and-burn system 2. Shifting agriculture 3. Three-field system Miniature from Sergy Radonezsky life, XVII c. Moscow

13 Slash-and-burn system slash burning clearing forest grain-crops 25 years 3 years 60 years Shifting agriculture slash tillage forest grain-crops 10 years Three-field system 25 years slash burning tillage rye/spring wheat/fallow fertilization (dunging 8t/ha*9yrs) no fertilization

14 The main parameters of land-use management scenarios Burning / without burning Percentage of burning wood Tillage duration Duration of soil relaxation (free forest development) Fertilization (composition, mass, frequency) / without fertilization

15 For each land-use management scenario 200-year ecosystem development was simulated with annual steps The impacts were simulated after 60 years of free forest development Trees were planted after impacts (beside the three-field system)

16 Case study B2 forest site class - sandy soddypodzolic soil, pine stands C3 forest site class - loamy soddypodzolic soil, birch stands Forest Inventory Data for experimental forestry Russkii Les, Moscow region, Russia

17 Dynamics of carbon in soil B2 forest site class kgc/m Slash&Burn 60 Slash&Burn 25 Field-Forest Shifting 25 Three-Field Three-Field +Fertilizations C3 forest site class Slash&Burn 60 Slash&Burn 25 Field-Forest Shifting 25 Three-Field Three-Field +Fertilizations 2 kgc/m Time (Years) Time (Years)

18 Results For the slash-and-burn and for the shifting agriculture, the frequency of impacts is crucial in Soil Organic Matter (SOM) dynamics The SOM stocks decrease more fast in the habitats of initial more rich soil

19 Critical reduction of SOM Slash-and-burn (25 years for relaxation), shifting agriculture, three-field without fertilization in years of impacts Slash-and-burn (60 years for relaxation) in more than 120 years of impacts Three-field system with fertilization no critical reduction of SOM

20 Extremal reduction of SOM Slash-and-burn (25 years for relaxation), shifting agriculture, three-field without fertilization in years of impacts Slash-and-burn (60 years for relaxation) in more than 180 years of impacts Three-field system with fertilization no extremal reduction of SOM

21 Some modelling questions too much reduction of SOM small difference between a final reduction of SOM in poor and in rich soil Why? Decomposition speed is high too much Decomposition coefficients for arable layer apply to all soil depth No compartment of strongly stable SOM To differ SOM compartments in mineral soil

22 Soil profiles of different history without agricultural use after agricultural use, mainly slash-and-burn Komi republic, European Russia

23 Soil profiles of different history without agricultural use after long-term agricultural use, mainly shifting agriculture Vologda region, European Russia

24 Soil profiles of different history without agricultural use Kaluga region, European Russia after long-term agricultural use, mainly three-field system without fertilization

25 Modelling of historical land-use management allows for i. assessing critical loads of historical land-use systems for dynamics of soil organic matter ii. assessing critical lifetime of different agricultural systems in different environmental conditions iii. getting new data for understanding ecosystem history and for testing historical reconstruction concepts

26 Thank You for Your Attention! Licevoj svod, XVI c. Moscow