The role of the vegetation structure, primary productivity and senescence derived from airborne LiDAR and hyperspectral data for birds diversity and rarity on a restored site
Abstract
Management of restored areas requires ecologically meaningful spatial data providing objective measures of restoration success. Understanding relationships between species diversity on the one hand and habitat heterogeneity and productivity on the other can help establish such measures and prioritize restoration management.
We used airborne LiDAR and hyperspectral data to derive characteristics of vegetation structure, primary productivity and senescent vegetation (i.e. old dead vegetation) for prediction of richness and rarity of bird communities colonizing newly available habitats restored after coal mining. In addition, we analysed, which type of restoration (i.e. agricultural, forest, or spontaneous succession) results in more favourable conditions.
The boosted regression trees explained 52% and 12% of deviance of overall species richness and rarity, respectively. We found that the overall species richness was strongly affected by the variance in vegetation structure, while the rarity was also affected by the presence of senescent vegetation.
The relative importance of variables differed between the richness and rarity. The shrub cover had a strong positive effect on both, while the tree cover had a strong positive effect on species richness.
The herbaceous cover and presence of senescent vegetation had positive effects on species rarity. This study, therefore, supports the necessity to create a mosaic of habitats with heterogeneous vertical structure including all layers of vegetation and highlights the importance of senescent vegetation.
Combination of forests restoration with sites left to spontaneous succession appears to be the best strategy to increase both bird species richness and rarity in newly restored sites after coal mining.