MILES planted birch plots: MOORCO – Moorland colonisation
Background
These plots are part of the MOORCO project and were established in order to experimentally test the results from the MOORCO chronosequence plots. The effects of birch (Betula sp.) on moorland soils is being tested using a replicated paired plot experiment established at three sites in Scotland in the early 1980s. Data collected from these plots has enabled us to assess the ecological engineering impact of birch on above and below-ground species and processes.
Key results
- Under the birch, plant species richness decreased and the ground vegetation composition changed, from being dominated by Calluna vulgaris to being dominated by either grasses and Vaccinium myrtillus or bare ground depending on the density of the trees.
- The depth of the soil organic horizon, its moisture content and percentage carbon were all smaller under the birch than under the heather.
- Concentrations of available phosphorus and mineralisable-N were significantly greater in the soil under birch than under the heather plots.
- Decomposition was faster in the birch than in the heather plots.
- The abundance and species richness of Collembola and oribatid, mesostigmatid and prostigmatid mites were all significantly greater under the birch than under the heather.
- Under birch, total microbial biomass (total phospholipid fatty acids (PLFAs)) declined, species richness increased and the ratio of fungal:bacterial PLFA declined.
- The fungal PLFA marker increased with increasing organic matter and depth of the LFH and O soil horizons, characteristics associated with moorland soils.
- Bacterial PLFAs increased with increasing birch canopy cover.
- The fungal community (as measured using polymerase chain reaction–denaturing gradient gel electrophoresis (PCR-DGGE)) of the birch plots was different from that in the heather plots and changes in the fungal community composition were related to the size of the birch trees in the plots.
- Changes in the soil microbial community were also related to changes in mineralizable N. Mineralizable N was correlated with both decreasing total soil microbial biomass and decreasing fungal:bacterial ratio.
- This work has provided experimental evidence that birch acts as a top-down engineer, driving cascading effects on both above- and below-ground communities, soil chemical and physical properties and ecosystem processes
See Publications for further details of results.
Sites
Site Name | Grid reference |
---|---|
Dalnalyne | NJ189175 |
Craggan (a) | NJ197326 |
Kerrow | NH336299 |
Experimental design
Treatments
- Planted plots: Betula pubescens planted at 1m spacing in plots
- Control plots: Open heather moorland
- Betula pendula: at Kerrow an addition 6 plots were established with Betula pendula planted
Replication
Paired plot design 6 control plots and 6 Betula pubescens plots at each site. In addition a further 6 plots at Kerrow with the second birch species
Data collected
Data type | Date | Details |
---|---|---|
Vegetation | 1985, 2003 | Species composition (% cover) |
Soil chemistry | 1978, 1986, 2003 | Al, C, C:N, Ca, Ca, Fe, K, LOI, Mg, Mn, moisture, N, Na, N-mineralization, P, pH |
Soil microbial | 2003 | PLFAs and DGGE |
Decomposition rates | 2003 | Filter papers and wooden sticks |
Soil physical properties | 1978, 2003 | LFH depth, O depth, bulk density |
Tree density and size | 2003 | Number, height and DBH |
Soil invertebrates | 2004 | Collembolla and mites (to species) Enchytraeidaes numbers |
Contact
MOORCO is a collaborative project across several groups and themes within the James Hutton Institute and with many different staff involved. In the first instance please contact Dr Ruth Mitchell for further details.