Drivers of plant community biodiversity: understory dynamics in longleaf pine savannas of North Carolina

UNCG Author/Contributor (non-UNCG co-authors, if there are any, appear on document)
Alyssa L. Young (Creator)
The University of North Carolina at Greensboro (UNCG )
Web Site:
Sally Koerner

Abstract: When properly managed, the longleaf pine (LLP) savanna ecosystem is one of the most biologically diverse habitats in the world due to the high density of understory plant species. The ecosystem has played a vital role in building the economy and culture of the U.S. southeast over centuries, but anthropogenic influences (e.g. land conversion, logging, fire suppression, etc.) have decimated this ecosystem and the biodiversity it holds, making restoration a necessity. This study investigated the drivers of biodiversity in LLP-wiregrass (Pinus palustris Mill. – Aristida stricta Michx.) savannas at small (1m2) and local (25m2) spatial scales in order to provide crucial information and focus for restoration strategies, improving the management and health of LLP savanna. I collected species composition data along with various site and stand level characteristics at 15 study plots across North Carolina. Various regression analysis techniques were then used to identify potential drivers of biodiversity. This study found considerable variation in biodiversity and community composition across study plots, with small scale richness ranging from 2 to 11.8, and a regional richness of 143 species. Additionally, A. stricta was found to be a significant driver of biodiversity at both spatial scales, and a unimodal relationship between productivity and richness was found, which agrees with results found in other LLP-A. stricta savanna communities. The presence of this dominant grass species has a positive effect on biodiversity, but with increasing abundance, there is a decrease in every biodiversity metric, with the ideal relative cover of wiregrass being 16% for enhancing and maintaining biodiversity at small scales. If LLP savanna land owners and managers can implement this ideal relative cover of wiregrass in their restoration strategies, the health and function can be restored to this ecosystem, as well as the biodiversity. Unfortunately, in today’s society, restoring the economically important tree in the LLP ecosystem is often all that people focus on as it has direct monetary benefits. However, the understory provides numerous other provisioning services such as carbon sequestration and erosion and flood control, habitat for endangered species, and biodiversity itself. LLP savannas are so much more than the LLP tree that dominates the skyline, and understanding the drivers of the understory biodiversity will aid in the restoration of an essential component of this critically threatened ecosystem.

Additional Information

Language: English
Date: 2019
Aristida stricta, Biodiversity, Longleaf Pine, Plant community, Productivity, Understory
Longleaf pine $z North Carolina
Savanna ecology $z North Carolina
Plant communities $z North Carolina
Understory plants $z North Carolina
Biodiversity $z North Carolina

Email this document to