Imprints of history in post-agricultural forests

Transcription

1 Imprints of history in post-agricultural forests Jaroslav Vojta Charles University in Prague Faculty of Sciences

2 Introduction PAPER I. Relative importance of historical and natural factors influencing vegetation of secondary forests in abandoned villages (Jaroslav Vojta - Preslia 79: ) PAPER II. Land use legacies in post-agricultural forests in the Doupovské Mountains, Czech Republic (Martin Kopecký & Jaroslav Vojta - Applied Vegetation Science 12: ) PAPER III. Woody vegetation continuity, topography, and distance to ancient forests have complex effects on the vegetation and species richness of abandoned pastures (Lucie Drhovská & Jaroslav Vojta - submitted)

3 Tocov about 1930 Introduction

4 Tocov about 2000 Introduction

5 Doupovské hory Introduction

6 Abandoned villages Introduction

7 Abandoned meadows and pastures Introduction

8 Abandoned arable fields Introduction

9 and ancient forests Introduction

10 Questions Questions Are there long-term effects of historical land use on soils in recent forests? - Papers I and II Does historical land use contribute to variability of forest vegetation? - Papers I and II What are the causes of differences between ancient and recent forests? - Papers I and III

11 Methods Methods Use of historical maps Correction for initial environmental conditions

12 Methods; use of historical maps Use of historical maps 1 st Military Survey ( ) 2 nd Military Survey ( ) Stable cadaster ( ) Land use map from 1952

13 Methods; Correction for initial environmental conditions Sampled points differ in in their history but also in their natural environment

14 Methods; Correction for initial environmental conditions Sampled points differ in in their history but also in their natural environment Therefore, we need co-variables that are unlikely to be changed by human activity. For example

15 Altitude Methods; Correction for initial environmental conditions

16 Slope Methods; Correction for initial environmental conditions

17 Methods; Correction for initial environmental conditions Wetness index And more: potential direct solar radiation, terrain shape index

18 Results Results Are there long-term effects of historical land use on soils in recent forests? Does historical land use contribute to variability of forest vegetation? What are the causes of differences between ancient and recent forests?

19 Results; historical land use and soils Historical land use affects important soil properties Locality Meadow Pasture Arable field N (g/kg) Tocov 4.4 A 4.6 A 2.7 B Lipoltov 4.3 A 3.3 AB 3.1 B C (g/kg) Tocov 43.8 A 49.6 A 27.3 B Lipoltov 40.4 A 36.2 A 30.3 A C:N ratio Both 9.7 A 10.7 B 9.7 A The variability of current soil properties is influenced by former inputs/outputs of nutrients.

20 Ln_p2o5 Phosphorus Results; historical land use and soils Soil properties differs between centres and peripheries of the villages Villlage centre VC - periphery VP The different soil properties in village centre and village periphery indicates different intensity of former human impact

21 Results; historical land use and vegetation Vegetation classification correlates with former land use GRP1 GRP2 GRP3 GRP4 GRP5 GRP6 Selected char. species Alnus glutinosa, Ranunculus repens, Filipendula ulmaria, Cirsium oleraceum Fraxinus excelsior, Milium effusum, Stachys sylvatica, Ranunculus auricomus Fraxinus excelsior, Ribes uva-crispa, Lysimachia nummularia, Galium odoratum Corylus avellana, Campanula persicifolia, Galium odoratum, Hieracium murorum Crataegus sp., Urtica dioica, Festuca gigantea, Geranium robertianum Crataegus sp., Agrostis capillaris, Myosotis arvensis, Knautia arvensis Pastures Mead. Arable f. Villages Totals 2 (5) 18 (4.3) 1 (4.7) 0 (7) 21 0 (5.4) 1 (4.7) 0 (5.2) 22 (7.7) 23 8 (14.9) 8 (12.8) 5 (14.4) 42 (21) 63 8 (3.1) 2 (2.6) 1 (3) 2 (4.3) (18.2) 17 (15.6) 20 (17.5) 13 (25.7) (9.5) 2 (8.1) 27 (9.1) 0 (13.3) 40 Totals

22 The effect of former land-use partly overlap with the effect of terrain attributes and soil properties Results; historical land use and vegetation

23 Results; Differences between ancient and recent forests Abandoned villages contribute to overall variability of forest vegetation DCA analysis. The two ordination axes explain 12.4% of the species variability (the first axis explains 7.3%).

24 Results; Differences between ancient and recent forests Significant differences between ancient wooded pastures and newly owergrown pastures CCA analysis. The two canonical axes explain 4.7% of the species variability

25 Results; Differences between ancient and recent forests Differences in species composition between ancient and recent forests are similar despite different origins of recent forests

26 Results; Differences between ancient and recent forests Correlation coefficients between species affinities to secondary forests Ellenberg indicator values and dispersal capacity Villages Pastures R L N M Dispersal

27 Number of forest species in recent forests is influenced particularly by distance to ancient forests but its importance is modified by other conditions (e.g. canopy cover). Results; Differences between ancient and recent forests

28 Conclusions Conclusions Soils are influenced by former agriculture in different ways. Levels of Important nutrients could be lowered as well as elevated depending on the manner and intensity of human influence. Information on past land use could help to interpret vegetation patterns as it reflects disturbance regimes, suitable habitat patterns, nutrient inputs/outputs in the past, and biotic legacies. These factors contribute to the variability of postagricultural forests. Also differences in successional age contribute to the overall diversity of forests in landscapes. The differences between ancient and recent forests are influenced by both environmental diffeences and constrains for species migrations

29 Thank you for your attention!