Title: Spatio-temporal trends of oak decline and mortality under periodic regiona drought in the Ozark Highlands of Arkansas and Missouri
Author: Fan, Zhaofei; Fan, Xiuli; Crosby, Michael K.; Moser, W. Keith; He, Hong; Spetich, Martin A.; Shifley, Stephen R.
Source: Forests. 3: 614-631.
Publication Series: Journal/Magazine Article (JRNL)
Description: At the forest landscape/region level, based on annual Forest Inventory and Analysis plot data from 1999 to 2010, oak decline and mortality trends for major oak species (groups) were examined in the Ozark Highlands of Arkansas and Missouri. Oak decline has elevated cumulative mortality of red oak species to between 11 and 15 percent in terms of relative density and basal area of standing dead oak trees, respectively. These values are three to five times higher than for white oak group and non-oak species. Oak decline and associated escalating mortality have occurred primarily in red oak species while the white oak group has maintained a relatively stable mortality rate that is comparable to non-oak species. Cross-correlation analyses indicate that mortality in the red oak group was significantly correlated with the growing season Palmer drought severity index (PDSI) and usually lagged two to three years following single drought events. Moreover, based on the past 17 years PDSI data, it appears that the cumulative impacts of drought may last up to 10 years. The Ozark Highlands experienced a severe drought extending from 1998 to 2000 and another milder drought from 2005 to 2006. These drought events triggered the escalation of mortality starting around year 2000. Spatially, high red oak mortality sites (hot spots with proportional basal area mortality >0.12) initially occurred in the central Ozarks and spread gradually over most of the Ozark Highlands as regional droughts continued. In contrast, sites with elevated white oak and non-oak mortality occurred sporadically, mainly in the southern portion (Arkansas) of the Ozark Highlands. During the most recent inventory period (2006-2010), over 60%, 7% and 5% of red oak, white oak and non-oak groups, respectively, had relative mortality rates of >12%.
Keywords: oak decline, drought, Forest Inventory and Analysis, kernel density smoothing, cross-correlation
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
- This publication may be available in hard copy. Check the Northern Research Station web site to request a printed copy of this publication.
- Our on-line publications are scanned and captured using Adobe Acrobat. During the capture process some typographical errors may occur. Please contact Sharon Hobrla, firstname.lastname@example.org if you notice any errors which make this publication unusable.
XML: View XML
Fan, Zhaofei; Fan, Xiuli; Crosby, Michael K.; Moser, W. Keith; He, Hong; Spetich, Martin A.; Shifley, Stephen R. 2012. Spatio-temporal trends of oak decline and mortality under periodic regiona drought in the Ozark Highlands of Arkansas and Missouri. Forests. 3: 614-631.
Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility