loading page

Light as a Resource, Stressor and Cue in Mediating Diversity-Productivity Relationships in Forests
  • +16
  • Laura Williams,
  • Raimundo Bermudez Villanueva,
  • Ethan Butler,
  • Jeannine Cavender-Bares,
  • John Couture,
  • Peter Hajek,
  • Johanna Klama,
  • Kyle Kovach,
  • Christian Messier,
  • Aboubakr Moradi,
  • Alain Paquette,
  • Maria Park,
  • Peter Reich,
  • Karen Rice,
  • Michael Scherer-Lorenzen,
  • Meredith Schuman,
  • Artur Stefanski,
  • Philip Townsend,
  • Zhihui Wang
Laura Williams
University of Minnesota, University of Minnesota

Corresponding Author:will3972@umn.edu

Author Profile
Raimundo Bermudez Villanueva
University of Minnesota Twin Cities, University of Minnesota Twin Cities
Author Profile
Ethan Butler
University of Minnesota Twin Cities, University of Minnesota Twin Cities
Author Profile
Jeannine Cavender-Bares
University of Minnesota, University of Minnesota
Author Profile
John Couture
Purdue University, Purdue University
Author Profile
Peter Hajek
University of Freiburg, University of Freiburg
Author Profile
Johanna Klama
University of Freiburg, University of Freiburg
Author Profile
Kyle Kovach
University of Wisconsin-Madison, University of Wisconsin-Madison
Author Profile
Christian Messier
University of Quebec at Montreal UQAM, University of Quebec at Montreal UQAM
Author Profile
Aboubakr Moradi
University of Zurich, University of Zurich
Author Profile
Alain Paquette
Universite du Quebec a Montreal, Universite du Quebec a Montreal
Author Profile
Maria Park
University of Minnesota, University of Minnesota
Author Profile
Peter Reich
University of Minnesota Twin Cities, University of Minnesota Twin Cities
Author Profile
Karen Rice
University of Minnesota Twin Cities, University of Minnesota Twin Cities
Author Profile
Michael Scherer-Lorenzen
University of Freiburg, University of Freiburg
Author Profile
Meredith Schuman
University of Zurich, University of Zurich
Author Profile
Artur Stefanski
University of Minnesota Twin Cities, University of Minnesota Twin Cities
Author Profile
Philip Townsend
University of Wisconsin, University of Wisconsin
Author Profile
Zhihui Wang
University of Wisconsin-Madison, University of Wisconsin-Madison
Author Profile

Abstract

In closed-canopy forests, the availability of photosynthetically active light has been a focal point of research, emphasizing the role of light as a resource in limiting carbon assimilation and individual tree growth. However, light shapes the functioning of forest ecosystems through multiple mechanisms. Here, using a series of studies from a network of tree diversity experiments, we explore the multifaceted ways in which light---in terms of both quantity and quality---shapes productivity in mixed-species forests. Spectral reflectance from remote sensing of forest canopies is being increasingly used to detect how tree diversity influences productivity. We demonstrate that airborne imaging spectroscopy captures functionally important differences among canopies related to their structure, chemistry, and underlying biological interactions. Ground-based analyses can show in detail how photosynthetically active light is partitioned among species in mixed-species communities. We show that greater interception of light and greater efficiency of light use, generated by inter- and intra-specific differences, combine to enhance productivity in mixed-species forests. Light may shape forest function not only as a resource but also as a stressor and cue. Plants can perceive light at various wavelengths, use this information to assess their neighborhoods, and subsequently adjust their physiology and allocation. We characterize how light quality---from the ultraviolet to shortwave infrared---varies among and within canopies of differing diversity. We explore how these diversity-light quality relationships arise and connect across levels of biological organization from leaf-level trait expression to forest function. Together these studies lend insight into light-mediated mechanisms that drive relationships between biodiversity and productivity in forest ecosystems---insights that are crucial to predict how biodiversity change will affect future forest function.