Active Projects

• The ecological role of silicon in tropical forests: consequences of inter- and intraspecific variation of silicon accumulation for woody seedling regeneration in the forest understory
  Silicon (Si) can contribute more than 10% of the dry mass of plants, and it is well-recognized that Si can alleviate stress due to drought, low nutrients and herbivory. These stressors play an important role for seedling regeneration, species distribution, forest dynamics and ecosystem function in tropical forests. Yet, the ecological role of Si in tropical forests, which harbor an enormous diversity and provide globally important ecosystem services, has hardly been addressed. In this study, we examine if and how inter- and intraspecific variation of leaf Si contents and spatial variation of soil Si availability affect seedling vital rates, i.e. growth and survival, in the understory - and how such effects change across environmental gradients. By integrating observational, experimental and trait-based approaches, the study will provide novel and important insights into the ecological role of silicon in tropical forests. At the same time, it addresses a main pending question in Si biology, if leaf Si accumulation in plants confers an inter- and intraspecific ecological advantage. [Details]
  
  
• Understanding how trait-based coordination of shade- and drought-tolerance regulates seedling dynamics in fragmented wet tropical forests
  Tropical forests stand threatened by climate change and fragmentation due to human land-use. It is therefore an urgent concern to disentangle the mechanisms by which fragmentation alters tropical forest dynamics in a drought-prone future climate. In this project, the overarching goal is to provide fundamental insights into how the coordination of responses to environmental drivers (drought, shade and nutrients) influence seedling dynamics in wet tropical forests subject to global change. Research is conducted in a human-modified forest complex in the central Western Ghats (India). We combine observational and experimental approaches to integrate detailed characterizations of microsite conditions and assessment of seedling performance and community composition in a network of seedling plots, with comparative assessments of relevant physiological, anatomical and morphological functional seedling traits. The study addresses fundamental knowledge gaps in trait-based ecology, advances our understanding of forest response to global change, and generates science-based inputs for restoration efforts geared towards supporting vulnerable species or selecting species that can mitigate the impacts of global change on biodiverse tropical forests. [Details]