Life Sciences Commons^™

Soil Microbial Community Dynamics In Response To Prescribed Extreme Fires Following Juniperus Virginiana Invasion In The Loess Canyons Of Nebraska, Julie A. Fowler

School of Natural Resources: Dissertations, Theses, and Student Research

In Nebraska and other regions of the Great Plains, the conifer Juniperus virginiana (eastern redcedar) is converting grasslands to dense woodlands. This is driven by the interacting drivers of fire suppression, altered grazing regimes, climate change and other anthropogenic factors, impacting the provisioning of ecosystem services. This vegetation state transition modifies water resource regulation and biogeochemical cycles leading to altered edaphic properties including soil microbial community composition. To restore these grasslands and control J. virginiana spread, prescribed extreme burns are implemented as a management tool through local prescribed burn associations. We hypothesized that the alternative state transition to dense J. …

Seed Rain–Successional Feedbacks In Wet Tropical Forests, Nohemi Huanca Nuñez, Robin L. Chazdon, Sabrina E. Russo

School of Biological Sciences: Faculty Publications

Abstract

Tropical forest regeneration after abandonment of former agricultural land depends critically on the input of tree seeds, yet seed dispersal is increasingly disrupted in contemporary human-modified landscapes. Here, we introduce the concept of seed rain–successional feedbacks as a deterministic process in which seed rain is shaped by successional dynamics internal to a forest site and that acts to reinforce priority effects. We used a combination of time series and chronosequence approaches to investigate how the quantity and taxonomic and functional composition of seed rain change during succession and to evaluate the strength of seed rain–successional feedbacks, relative to other …

Annual Report - 2020, John Erixson

Nebraska Forest Service: Publications

No abstract provided.

The Interspecific Growth–Mortality Trade-Off Is Not A General Framework For Tropical Forest Community Structure, Sabrina E. Russo, Sean M. Mcmahon, Matteo Detto, Glenn Ledder, S. Joseph Wright, Richard S. Condit, Stuart J. Davies, Peter S. Ashton, Sarayudh Bunyavejchewin, Chia-Hao Chang-Yang, Sisira Ediriweera, Corneille E.N. Ewango, Christine Fletcher, Robin B. Foster, C.V. Savi Gunatilleke, I.A.U. Nimal Gunatilleke, Terese Hart, Chang-Fu Hseih, Stephen P. Hubbell, Akira Itoh, Abdul Rahman Kassim, Yao Tze Leong, Yi Ching Lin, Jean-Remy Makana, Mohizah Bt. Mohamad, Perry Ong, Anna Sugiyama, I-Fang Sun, Sylvester Tan, Jill Thompson, Takuo Yamakura, Sandra L. Yap, Jess K. Zimmerman

School of Biological Sciences: Faculty Publications

Resource allocation within trees is a zero-sum game. Unavoidable trade-offs dictate that allocation to growth-promoting functions curtails other functions, generating a gradient of investment in growth versus survival along which tree species align, known as the interspecific growth–mortality trade-off. This paradigm is widely accepted but not well established. Using demographic data for 1,111 tree species across ten tropical forests, we tested the generality of the growth–mortality trade-off and evaluated its underlying drivers using two species-specific parameters describing resource allocation strategies: tolerance of resource limitation and responsiveness of allocation to resource access. Globally, a canonical growth–mortality trade-off emerged, but the trade-off …