Research Goals

Global seed supply is too poorly understood to even speculate on its contribution to the regeneration of forests that are increasingly lost to disturbance, climate change, and extensive human management. Through collaborations with more than 100 international researchers, the MASTIF project has been established to assimilate seed production data for 12.1 million tree-years in more than 1000 species from all vegetated continents. The MASTIF is funded by Nation Science Foundation (NSF) to Jim Clark since 1990s. PI Qiu and Clark are now linking seed production to seedling recruits by synthesizing satellite and airborne remote sensing with the MASTIF network. This new project is funded by the National Aeronautics and Space Administration (NASA), with end-user from the Pennsylvania Department of Conservation and Natural Resources (PA DCNR). PA DCNR will contribute both in-kind and computing support and collaborate with us to develop the decision-making tools. So far, we have addressed the following questions:

  • Tree size and age effects: does tree fecundity decline as tree grows larger and older (Qiu et al., 2021a)?
  • Map of life and traits: are there limits to reproductive potential whereby species sacrifice seed size in order to produce more seeds, a size-numbers tradeoff (Qiu et al., 2022)?
  • Soil effects: will access to resources mediate the limits to reproduction (Qiu et al., 2022)?
  • Masting syndrome: what are the causes and consequences of mast seeding at a global scale (Qiu et al., 2023)?
  • Canopy characteristics: how will tree fecundity respond to canopy nutrients, including N, P, K, Ca, and Mg (Qiu et al., in revision)?
  • Climate effects: how does individual fecundity change along the latitude gradient from dry tundra to wet tropics (Journe et al., 2022)?
  • Forest regeneration: do forest communities reorganize throughout the tree life stages including adult trees, fecundity, and seedling recruitment (Qiu et al., 2021b)?

Currently, there are six published papers listed in the following. There is a view point paper, two papers in progress, and one manuscript in revision, with results available from contacting the PI Qiu.