Recommended
Recommended
More Related Content
What's hot
What's hot (20)
Similar to Things fall apart
Similar to Things fall apart (20)
More from amellison17
More from amellison17 (7)
Recently uploaded
Recently uploaded (20)
Things fall apart
- 1. THINGS FALL APART Land-use history, non-native insects, climatic change, and the decline of a forest foundation species Aaron M. Ellison Harvard University, Harvard Forest
- 3. Frontiers in Ecology and the Environment (2005) Benjamin Baiser Audrey Barker Plotkin Peter Bettman-Kerson Hannah Buckley Brad Carlin Brad Case Aimeé Classen Eric Davidson Ally DeGrassi Joe Elkinton Elizabeth Farnsworth Matthew Fitzpatrick David Foster Joe Kendrick Michael Lavine Nicky Lustenhouwer Heidi Lux Liza Nicoll Dave Orwig Annie Paradis Mainsha Patel Adam Porter Evan Preisser Sydne Record Tara Sackett Kathleen Savage Jonathan Thompson Mark Van Scoy Lance Waller Collaborators
- 4. Map: Matthew Fizpatrick/Ecological Applications (2012) [Data: HF191] DaveOrwig/HarvardForest Tsuga canadensis (L.) Càrr. [Pinaceae]
- 5. Yale University Press (2014) The way a crow Shook down on me The dust of snow From a hemlock tree Has given my heart A change of mood And saved some part Of a day I had rued. ― Robert Frost
- 6. Flux(mgCm-2hr-1) 0 100 200 300 400 SoilTemperature(oC) at10cm 0 5 10 15 20 25 VolumetricSoilMoisture (gH2Ocm -3 soil) 0.0 0.2 0.4 0.6 1995 1996 1997 1998 1999 2000 Soil respiration, temperature, and water content in a hardwood stand, a young hemlock stand, and the old hemlock stand at Harvard Forest Unpublished data of E.A. Davidson, S.E. Trumbore, and J.L. Hadley [Data: HF072, HF103, HF153] Hemlock basal area (percent of total) 0 20 40 60 80 100 Numberofantspecies 2 4 6 8 10 12 14 CT sites MA sites r2 = 0.50, P = 0.002 Hemlock basal area (percent of total) 0 20 40 60 80 100 IncidenceofFormicaspp. (probabilityofoccurrence) 0.0 0.2 0.4 0.6 0.8 1.0 P = 0.045 Ellison, Chen, Díaz, Kammerer-Burnham, and Lau, Proc. 3rd Symp. HWA in eastern N. Am. (2005). [Data: HF065]
- 7. Kathy Shields USDA Forest Service Photos: David Orwig/Harvard Forest SEM: USFS
- 9. Phohtos: Dave Orwig/Harvard Forest
- 10. Long-term research questions • What is the process by which the system reorganizes following loss of hemlock, and how is it related to the biology of hemlock and the adelgid? • What new endpoints will the system reach following this reorganization? • How does logging vs. the adelgid alter these transitions and endpoints? • Has this happened before, and what can we learn from history?
- 11. Research approach Retrospective studies Decades to centuries Patterns of insect dis- persal and logging Years to decades Whole-tree physiology Days to years Insect physiology and effect on trees Days to years Soil ecosystem pro- cesses Months to decades Atmospheric CO2 and H2O flux Instants to years Forest structure and environmental varia- bles Months to years Structure of associat- ed biota Years to decades ED and PnET models Decades to centuries
- 12. Paleo-hemlock decline Raw data interpolated to 50-year time intervals by Julia Jones ; LOI data and pollen data courtesy of Ed Faison and Wyatt Oswald; GISP2 data from http://www.gisp2.sr.unh.edu/ [Data: HF184, 185, 186]
- 13. Post-agriculture hemlock recovery • Hemlock has steadily increased in abundance in the last century, especially following the loss of American chestnut (Castanea dentata), another forest dominant (foundation species?) due to chestnut blight, and after the 1938 hurricane. • In the last 100 years, hemlock has not been systematically logged. • The adelgid arrived in the northeast ~1980.
- 14. Ellison (2014) Advances in Ecology [Data: HF001]
- 15. Model/maps: Fitzpatrick et al. (2010) Ecology [Data: HF190]
- 16. Model/maps: Fitzpatrick et al. 2012 Ecological Applications [Data: HF190]
- 20. • Eight 90 × 90 m (0.81 ha) plots established 2003 (Audrey Barker Plotkin, Aaron Ellison, David Foster, Dave Orwig, Eric Davidson) • Blocked BACI design with 4 treatments/block: • Hemlock control • Girdle all hemlocks • “Commercial” cut of hemlocks and other merchantable timber • Hardwood control • 2 years pre-treatment data • Treatments applied winter/spring 2005 Project description: Ellison et al. (2010) Methods in Ecology & Evolution
- 21. Ellison et al. (2014) Rhodora; [Data: HF000, HF001, HF086, HF126, HFDA 1935-01, 1944-10, 1950-17, HFDA 1980-13, 1933-05, HFAdm 137, HF Stand Records Simes Tract, MASS-GIS]
- 23. • All trees tagged, measured, and mapped • Stand reconstruction (deed research and dendrochronology) • Sap flow during girdling • Seed bank composition • Seed dispersal and recruitment • Understory vegetation composition • Animal diversity and abundance • Ants • Beetles • Amphibians • Birds • Mammals: from rodents to moose • Adelgid colonization Ongoing projects
- 24. • Environmental measurements • Temperature (10-minute intervals) • Light (canopy photos twice/year) • Canopy structure (ground-based laser) • Temporal trajectory (panorama) • Quantitative soil pits • Nitrogen dynamics • Nitrogen availability • Nitrogen mineralization • Throughfall chemistry • Carbon dynamics • Soil respiration • Litterfall • Coarse woody debris • Ants and ecosystem function (complete) Plot 1 – Girdled – 2006 05 26 Ongoing projects
- 25. Lustenhouwer et al. (2012) Ecosphere [Data: HF107, HF126]
- 26. Kendrick et al. (2015) Ecosphere [Data: HF107] Adelgid colonization Adelgid colonization
- 28. Vegetation structure and compositional change driven by seed bank, seed rain, and understory responses. Farnsworth et al. (2012) Canadian Journal of Forest Research [Data: HF105, HF106, HF120]
- 29. PC-1 Aralia nudicaulis Dendrolycopodium obscurum Lysimachia borealis PC-2 Berberis thunbergii Lonicera canadensis Dryopteris carthusiana Ilex verticillata Osmundastrum cinnamomeum Epigaea repens Viburnum acerifolium Rhododendron periclymenoides PC-3 Lysimachia quadrifolia Carex spp. Rubus allegheniensis Aralia hispida Rubus idaeus Panicum sp. Ellison et al. (2016) Forests [Data: HF106]
- 30. Sackett et al. (2011) Ecosphere [Data: HF177]
- 31. Kendrick et al. (2015) Ecosphere [Data: HF160]
- 33. Kendrick et al. (2015) Ecosphere [Data: HF160, HF179]
- 35. Historic data from VEMAP2 grid cell elements of New England. Projections using Canadian and Hadley GCMs; published by New England Regional Assessment Group (2001) Preparing for a changing climate: the potential consequences of climate variability and change. New England regional overview. University of New Hampshire and U.S. Global Change Research Program. Regional climate models project warmer and wetter conditions in the northeast USA
- 36. 1850 1997 USDA, US Census and FAO data and projections Historical and contemporary land-use Model: Albani et al. 2010 Canadian Journal of Forest Research 40: 119
- 37. Integrated model of adelgid spread and impact Rate of hemlock decline from Dave Orwig AFLP data from Annie Paradis and Adam Porter Average year of HWA infestation from stochastic model Albani et al. (2010) Canadian Journal of Forest Research
- 38. Modeled impact of HWA infestation at the site scale on above-ground biomass trajectories (left) for grasses (G), early-, mid- (MSD), and late- (LSD) successional deciduous trees, pines (NP, SP), hemlock (LSE); and carbon fluxes (right: NPP and heterotrophic respiration) for central Massachusetts (top) and central New Hampshire (bottom). Model: Albani et al. (2010) Canadian Journal of Forest Research
- 39. Impact of the adelgid on net ecosystem productivity (NEP), expressed as difference between the infestation and the no infestation scenario. Note the characteristic pattern of decreased and then increased NEP as the infestation moves from east to west. Model: Albani et al. (2010) Canadian Journal of Forest Research
- 40. J.W. Munger [Data: HF004] Hemlock Wooly Adelgid J.W. Munger [Data: HF206]
- 41. Turning and turning in the widening gyre The falcon cannot hear the falconer; Things fall apart; the centre cannot hold; Mere anarchy is loosed upon the world, The blood-dimmed tide is loosed, and everywhere The ceremony of innocence is drowned; The best lack all conviction, while the worst Are full of passionate intensity. —from The Second Coming by W. B. Yeats (1920)