Assessing spatial and temporal patterns of canopy decline across a diverse montane landscape in the Klamath Mountains, CA, USA using a 30-year Landsat time series
- 48 Downloads
Tree mortality is of considerable concern, but the magnitude and extent of forest canopy decline are relatively unknown in landscapes with high levels of topographic complexity, spatial heterogeneity, and species diversity. We assessed 30 years of canopy decline, including a 5-year period characterized by extreme drought, in one of North America’s most diverse landscapes in the Klamath Mountains of northern California, USA.
(1) Characterize tree mortality by species, (2) Quantify temporal and spatial patterns of remotely-sensed canopy decline in relation to climate, (3) Compare canopy decline among vegetation types, topographic settings, and stand structural classes during drought.
We characterized tree mortality by species with field data and quantified the role of climate on canopy decline with a 30-year Landsat time series. We assessed and compared the role of topography and stand structure on canopy decline during drought.
Most tree mortality and canopy decline occurred at higher elevations in Shasta red fir (Abies magnifica var. shastensis) and subalpine forests. Annual area of canopy decline was positively correlated with summer temperature and minimum vapor pressure deficit but not precipitation. The area of canopy decline was three times greater during the drought. The magnitude of decline was greatest at higher elevations, on more exposed, southwestern slopes, and in stands with old-growth structure. Stands in valleys and low slopes experienced relatively little decline.
Our study demonstrates the vulnerability of high elevation, old-growth forests to increasing temperature and suggests the potential for refugia from drought in diverse, heterogeneous landscapes.
KeywordsCanopy decline Shasta red fir (Abies magnifica var. shastensis) Topographic refugia Tree mortality LandTrendr Climate change
This research was funded in part through the US Forest Service (Agreement #11-CS-11051000-023) and the Agricultural Research Institute (Agreement 15-06-007). The authors would like to thank Dr. Buddhika Madurapperuma and Dr. Paul Bourdeau for their useful comments on the manuscript. Much thanks to Connor Adams, Harrison Stevens, Angelo DeMario, Arthur Grupe, Stefani Brandt, Addison Gross, Maria Friedman, Jenell Jackson, John Mola, Sam Johnson, James Adam Taylor, and Elizabeth Wu for their assistance in collecting field data.
- Allen CD, Macalady AK, Chenchouni H, Bachelet D, McDowell N, Vennetier M, Kitzberger T, Rigling A, Breshears DD, Hogg EH, Gonzalez P, Fensham R, Zhangm Z, Castro J, Demidova N, Lim JH, Allard G, Running SW, Semerci A, Cobb N (2010) A global overview of drought and heat-induced tree mortality reveals emerging climate change risks for forests. For Ecol Manag 259(4):660–684CrossRefGoogle Scholar
- Coleman RG, Kruckeberg AR (1999) Geology and plant life of the Klamath-Siskiyou Mountain region. Nat Areas J 19(4):320–340Google Scholar
- Daly C, Conklin DR, Unsworth MH (2010) Local atmospheric decoupling in complex topography alters climate change impacts. Int J Climatol 30(12):1857–1864Google Scholar
- DeSiervo MH, Jules ES, Bost DS, Stigter DLE, Butz RJ (2018) Patterns and drivers of recent tree mortality in diverse conifer forests of the Klamath Mountains, California. For Sci 64(4):371–382Google Scholar
- Gruell GE (2001) Fire in Sierra Nevada forests: a photographic interpretation of ecological change since 1849. Mountain Press, MissoulaGoogle Scholar
- Hicke JA, Meddens AJ, Kolden CA (2015) Recent tree mortality in the western United States from bark beetles and forest fires. For Sci 62(2):141–153Google Scholar
- Jenness J (2006) Topographic position index extension for ArcView 3x, v 13a. Jenness Enterprises. http://www.jennessent.com/downloads/tpi_documentation_online.pdf. Accessed 27 Dec 2018
- Kauffmann ME (2012) Conifer country: a natural history and hiking guide to 35 conifers of the Klamath Mountain region. Backcountry Press, KneelandGoogle Scholar
- Keeler-Wolf T (1984) Vegetation map of the upper Sugar Creek drainage, Siskiyou County. Unpublished report on file. Pacific Southwest Research Station, AlbanyGoogle Scholar
- Manion PD (1991) Tree disease concepts, 2nd edn. Prentice-Hall, Englewood CliffsGoogle Scholar
- McGarigal K, Marks BJ (1995) FRAGSTATS: spatial pattern analysis program for quantifying landscape structure. Gen Tech Rep PNW-GTR-351. US. Department of Agriculture, Forest Service, Pacific Northwest Research Station, Portland, OR, vol 122, p 351Google Scholar
- McGarigal K, Cushman SA, Ene E (2012) FRAGSTATS v4: spatial pattern analysis program for categorical and continuous maps computer software program. Produced by the authors at the University of Massachusetts, AmherstGoogle Scholar
- McKelvey KS, Skinner CN, Chang C, Erman DC, Husari SJ, Parsons DJ, van Wagtendonk JW, Weatherspoon PC (1996) An overview of fire in the Sierra Nevada. In: Sierra Nevada Ecosystem Project, final report to congress, vol II. Assessments and Scientific Basis for Management Options Davis, CA, University of California, Centers for Water and Wildland Resources Report No 37, pp 1033–1040Google Scholar
- Millar CI, Westfall RD, Delany DL, Bokach MJ, Flint AL, Flint LE (2012) Forest mortality in high-elevation whitebark pine (Pinus albicaulis) forests of eastern California, USA; influence of environmental context, bark beetles, climatic water deficit, and warming. Can J For Res 42(4):749–765CrossRefGoogle Scholar
- Morelli TL, Daly C, Dobrowski SZ, Dulen DM, Ebersole JL, Jackson ST, Lundquist JD, Millar CI, Maher SP, Monahan WB, Nydick KR, Redmond KT, Sawyer SC, Stock S, Beissinger SR (2016) Managing climate change refugia for climate adaptation. PLoS ONE 11(8):e0159909CrossRefPubMedPubMedCentralGoogle Scholar
- Parker I, Matyas W (1979) CALVEG: a classification of Californian vegetation. US Department of Agriculture, Forest Service, Pacific Southwest Region Station, AlbanyGoogle Scholar
- R Core Development Team (2017) R: a language and environment for statistical computing. R Foundation for Statistical Computing, ViennaGoogle Scholar
- Rapacciuolo G, Maher SP, Schneider AC, Hammond TT, Jabis MD, Walsh RE, Iknayan KJ, Walden GK, Oldfather MF, Ackerly DD, Beissinger SR (2014) Beyond a warming fingerprint: individualistic biogeographic responses to heterogeneous climate change in California. Glob Change Biol 20(9):2841–2855CrossRefGoogle Scholar
- Reilly MJ, Spies TA, Littell J, Butz R, Kim J (2018) Vulnerability of vegetation to climate change and disturbance in the Northwest Forest Plan area. In: Synthesis of science to inform land management within the Northwest Forest Plan Area. USFS PNW GTR-966 vol 1Google Scholar
- Safford HD, Van de Water KM (2014) Using fire return interval departure (FRID) analysis to map spatial and temporal changes in fire frequency on national forest lands in California. US Department of Agriculture, Forest Service, Pacific Southwest Research Station, vol 59, p 266Google Scholar
- Safford HD, van de Water K, Schmidt D (2011) California fire return interval departure (FRID) map metadata: description of purpose, data sources, database fields, and their calculations. USDA Forest Service, Pacific Southwest Region, VallejoGoogle Scholar
- Sawyer JO (2007) Why are the Klamath Mountains and adjacent North Coast floristically diverse? Fremontia 35(3):3–11Google Scholar
- Sawyer JO, Thornburgh DA (1971) Vegetation types on granodiorite in the Klamath Mountains, California. Report to the Pacific Southwest Forest and Range Experiment Station, Berkeley, California PSW COOP-AID agreement supplement #10 unpublished report on file, Pacific Southwest Research Station, Albany, CaliforniaGoogle Scholar
- Sawyer JO, Thornburgh DA (1974) Subalpine and montane forests on granodiorite in the central Klamath Mountains of California. Unpublished report to Pacific Southwest Forest and Range Exp. Sta., Berkeley, CaliforniaGoogle Scholar
- Skinner CN (2003) Fire history of upper montane and subalpine lake basins in the Klamath Mountains of northern California. In: Proceedings of fire conference 2000: the first national congress on fire ecology, prevention and management, Misc. Pub. 13 Tall Timbers Research Station, Tallahassee, FL, pp 145–151Google Scholar
- van der Molen MK, Dolman AJ, Ciais P, Eglin T, Gobron N, Law BE, Meir P, Peters W, Phillips OL, Reichstein M, Chen T, Dekker SC, Doubková M, Friedl MA, Jung M, van den Hurk BJJM, de Jeu RAM, Kruijt B, Ohta T, Rebel KT, Plummer S, Seneviratne SI, Sitch S, Teuling AJ, van der Werf GR, Wang G (2011) Drought and ecosystem carbon cycling. Agric For Meteorol 151(7):765–773CrossRefGoogle Scholar
- Williams AP, Allen CD, Macalady AK, Griffin D, Woodhouse C, Meko D, Swetnam T, Rauscher Seager R, Grissino-Mayer HD, Dean JS, Cook ER, Gangodagamage C, Cai M, McDowell NG (2013) Temperature as a potent driver of regional forest drought stress and tree mortality. Nat Clim Change 3(3):292–297CrossRefGoogle Scholar
- Wills RD, Stuart JD (1994) Fire history and stand development of a Douglas-fir/hardwood forest in northern California. Northwest Sci 68(3):205–212Google Scholar