Plant Community and Soil Relationship Following Wildfires From Nuees Ardentes on Mt. Merapi

At a local scale, vegetation patterns are known to have strong relationships with edaphic factors. In the case of Mt. Merapi volcanic eruption, studies on the relationships between edaphic factors and plant community composition and distribution following the nuees ardentes-ignited wildfires will provide valuable information on post-disturbance secondary successional processes. We collected soil and vegetation data from five different ages of nuees ardentes fire-affected secondary succession forests and one un-affected forest. Our results showed significant correlation of species composition and edaphic factors among sites of secondary forests. Nitrogen and soil water content were found to be the important factors in structuring species composition in the youngest site, where the N-fixing legume species such as Calliandra callothyrsus was found to be dominant. CCA ordination also revealed strong negative correlation between nitrogen content and legume group, while non-legume group were positively correlated with other edaphic factors such as phosphor and potassium. These findings suggested that changes in soil properties due to recovery of this system after volcanic eruption correlated with plant community composition and can be crucial factors in driving the successional trajectory. Understanding ecosystem reassembly process and trajectory of succession will improve how we approach the restoration of Mt. Merapi ecosystem

A systematic review reveals changes in where and how we have studied habitat loss and fragmentation over 20 years

Habitat loss and fragmentation are global threats to biodiversity and major research topics in ecology and conservation biology. We conducted a systematic review to assess where – the geographic locations and habitat types - and how – the study designs, conceptual underpinnings, landscape metrics and biodiversity measures - scientists have studied fragmentation over the last two decades. We sampled papers from 1994 to 2016 and used regression modelling to explore changes in fragmentation research over time. Habitat loss and fragmentation studies are geographically and taxonomically biased. Almost 85% of studies were conducted in America and Europe, with temperate forests and birds the most studied groups. Most studies use a binary conceptual model of landscapes (habitat versus non-habitat) and static measures of biodiversity. However, research on fragmentation is slowly shifting from a focus on coarse patterns to more nuanced representations of biodiversity and landscapes that better represent ecological processes. For example, empirical research based on gradient or continuum models, that offer new insights into landscape complexity and species-specific responses to habitat fragmentation, are increasing in prevalence. We recommend that fragmentation research focuses on developing knowledge on underlying mechanisms and processes of how species respond to landscape changes, and that fragmentation studies be conducted in the full range of habitats currently experiencing high rates of landscape modification. This is crucial if we are to understand relationships between biodiversity and ecosystems and to develop effective management strategies in fragmented landscapes