Vegetation gain (amount) encroachment
Expansion of whole plant communities (native or exotic) into an area as a consequence of an increase in woody plant density or extent so that the natural equilibrium of woody plant layer (trees and shrubs) and herbaceous (grass and forb) layer densities is shifted towards woody species.
EVIDENCE FOR IMPACTS
In the case of this impact, the evidence requirements are:.
- Canopy cover
- Canopy height
- Woody above ground biomass.
- Green (photosynthetic) fraction
PRESSURE DATASETS
- The Pressure datasets needed are accessible via Living Earth:
CASE STUDY
- The case study is the Amazon Basin where pastures used actively for extended periods but then abandonmed are encroached upon from refugia of plant communities (e.g., Vismia species)
See also https://www.swissdatacube.org/index.php/publications/))
RESULTS).
- The following shows the net change in cover from herbaceous to woody in the lifform layer with a corresponding increase in above ground biomnass that is considered significnat (based on the Mann-Kendall and Senn slope)