atkinsjeff/LaserQuest: LaserQuest 1.0.1

LaserQuest

Repository Overview

This repository serves as a central location for specific manuscripts for the VCU Forest Ecology Lab at Virginia Commonwealth University (Dr. Christopher M. Gough, PI), as such, DOIs will be minted following the addition of each manuscript and the supporting code and data that is added to this repository. Additionaly, the minor version number (0.x.0) will also be updated. This readme will serve as a general guide until vignettes and supporting documentation are added.

The general structure of this repo is that all data, code, and text for each manuscript is contained with in the /manuscripts folder within a unique and distinct subfolder. Unless copyright law specficially restrict it, manuscript text will be included therein as well.

Included Manuscripts and Projects

Forest structural complexity and biomass predict first-year carbon cycling responses to disturbance

This paper is currently in review

Authors: Christopher M. Gough¹, Jeff W. Atkins¹, Ben Bond-Lamberty², Elizabeth A. Agee³, Kalyn R. Dorheim² Robert T. Fahey⁴, Maxim S. Grigri¹, Lisa T. Haber¹, Kayla C. Mathes¹, Stephanie C. Pennington², Alexey N. Shiklomanov⁵, Jason M. Tallant⁶

1. Department of Biology, Virginia Commonwealth University, Box 842012, 1000 West Cary St., Richmond, VA 23284
2. Joint Global Change Research Institute, Pacific Northwest National Laboratory, 5825 University Research Ct, College Park, MD 20740
3. Environmental Sciences Division and Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
4. Department of Natural Resources and the Environment & Center for Environmental Sciences and Engineering, University of Connecticut, 1376 Storrs Road, Storrs, CT 06269
5. NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
6. University of Michigan, Biological Station and Department of Ecology and Evolutionary Biology, Pellston, MI 49769, USA

*Corresponding Author: cmgough@vcu.edu Submitted to: Ecosystems https://www.springer.com/journal/10021

Abstract

The pre-disturbance vegetation characteristics that confer initial carbon (C) cycling resistance to disturbance are not well known. To address this gap, we initiated the Forest Resilience Threshold Experiment (FoRTE), a manipulative study comprised of replicated factorial combinations of four levels (control, 45%, 65% and 85% gross defoliation) of disturbance severity and two disturbance types (targeting upper or lower canopy strata) implemented by stem girdling >3600 trees. Applying a standardized stability framework in which resistance was calculated as the first-year natural log response ratio of disturbance and control treatments, we investigated to what extent pre-disturbance levels of species diversity, aboveground woody biomass, leaf area index, and canopy rugosity – a measure of structural complexity – predict the initial resistance of subcanopy light-saturated leaf CO₂ assimilation (A_sat), aboveground wood NPP (ANPP_w) and soil respiration (R_s) to phloem-disrupting disturbance. We found that above-ground C cycling processes, A_sat and ANPP_w, were highly resistant to increases in disturbance severity, while Rs resistance declined as severity increased. Disturbance type had no effect on first-year resistance. Pre-disturbance aboveground woody biomass was a positive predictor of ANPP_w resistance and, along with canopy rugosity, was negatively related to R_s resistance. Subcanopy A_sat resistance was not related to pre-disturbance vegetation characteristics. Stability of C uptake processes along with Rs declines suggest the net C sink was sustained in the initial months following disturbance. We conclude that biomass and complexity are significant, but not universal, predictors of initial C cycling resistance to disturbance. Our findings highlight the utility of standardized stability measures when comparing functional responses to disturbance.

Code and data for this paper are availble (scripts included are in both R and SAS):

/manuscripts/gough_et_al_2020_ecosystems

 DOI: https://doi.org/10.5281/zenodo.3779040

This paper is part of the Forest Resilience Threshold Experiment.

Community and structural constraints on the complexity of eastern North American forests

This paper has been accepted at Global Ecology and Biogeography “Laserquest” investigators use remote sensing to advance understanding of ecosystem structure-function relationships across spatial scales, from the eco- to macrosystem. The extended research team includes physiological, community, ecosystem ecologists, carbon cycling scientists, applied forest ecologists, remote sensing scientists, and ecosystem and earth system modelers. Through partnerships with observing networks such as NEON and Ameriflux, and using novel ecological observations obtained with the aid of new technologies, Laserquest researchers seek to improve model representation of ecosystem structure.

Code and Data for this paper are availble:

/manuscripts/gough_et_al_2020_geb

With in this folder PhylogeneticDiversity.R recreates the associated analysis and links to the data.

Direct Link

The original release of this project can be found at https://github.com/atkinsjeff/LaserQuest/releases/tag/0.1.1

Authors: Christopher M. Gough (VCU), Jeff W. Atkin (VCU), Robert T. Fahey (UConn), Brady S. Hardiman (Purdue), Elizabeth A. LaRue (Purdue)

Acknowledgements: This work was supported by the National Science Foundation’s Division of Emerging Frontiers, Awards 1550657 (CMG), 1550650 (RTF), and 1550639 (BSH). We thank the National Ecological Observatory Network (NEON), and particularly Courtney Meier, for data and technical support.