What We Won t Talk About Today (Pablo Pina s PhD Project) Outline. MPB Life Cycle. MPB as a Disturbance Agent

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1 PhD Project Proposal: Effects of Simulated Mountain Pine Beetle Attack on Vegetation and Below-Ground Attributes in Lodgepole Pine Forests of the Western Alberta Foothills Anne McIntosh Macdonald Lab Lunch May 7, What We Won t Talk About Today (Pablo Pina s PhD Project) This project also seeks to determine initial effects of variable intensity of simulated MPB on stand water balance/hydrology 2 Introduction Objectives Outline Methods Preliminary Results Discussion 3 Mountain Pine Beetle (MPB) Dendroctonus ponderosae Native bark beetle of western North America pine forests Most damaging biotic disturbance agent in mature lodgepole pine in western Canada The current BC outbreak is order of magnitude > in area and severity than all previous recorded Highly evolved mutualistic relationship with ophiostomoid blue stain fungi Kills trees by girdling them mass attack 4 MPB Life Cycle MPB as a Disturbance Agent Larger & older trees selectively killed but remain standing (vs logging) needles can a.galleries in remain 3-5 yrs+ phloem Understory & soil layers not directly affected b. Eggs in (vs logging or fire) gallery Return of nonvolatile nutrients to the soil & c. Mature larva response of vegetation production are slower d. Pupa (vs stand-replacing fire) e. Teneral/new adults 6 f. mature adult 1

2 Lodgepole Pine (Pinus contorta var. latifolia) MPB + PICO = From Green to Red Fire-dependent pioneer species (*serotinous cones) Fire suppression changes trajectory In Alberta, pine represents ~ 41% of coniferous forests (7x106 ha) The majority of pine in Alberta is lodgepole pine and jack pine (P. banksiana Lamb.) 7 MPB Climate Change Implications Are Big Next Stop: Alberta (Kurz et al. 2008) BC cumulative impact = 270 Mt C released (~36-g-C/m2/yr over 374,000 km2) Worst yr impacts from MPB ~75% of mean annual direct forest fire emissions from all of Canada From sink large net C source MPB Expansion: Jack Pine (Pinus banksiana) MPB research has 1 focused on BC, > history of epidemics Former climatically hostile environments will become climatically benign, allowing MPB to significantly expand its range Native Invasive

3 Introduction Objectives Outline Methods Preliminary Results Discussion Objective 1 - Overstory Characterize the overstory forest structure for a set of mature lodgepole pine stands in the western Alberta foothills before, and 1 & 2 yrs after 4 levels of simulated MPB kill and/or forest management Baseline data for other aspects of the study Insight into standing above-ground C pools Objective 2 - Understory Quantify differences in the understory plant community composition before, and 1 & 2 yrs after 4 levels of simulated MPB kill and/or forest management in lodgepole pine forests in the western Alberta foothills Seedlings/Saplings (pine, spruce, balsam) Vascular plants (shrubs, forbs, graminoids) Non-vascular plants (bryophytes, lichens) 15 Objective 2 - Hypothesis As tree mortality increases there will be an increase in: Vascular plant cover Plant diversity will peak with medium-level of disturbance (increased stand heterogeneity more niches) Growth of seedlings/saplings (advance regeneration) present but limited change in overall seedling/sapling abundance b/c of serotiny Release from competition with trees for water, nutrients, & light* (likely not much change in the light over the duration of this study except salvage harvest that will follow when needles drop) 16 Objective 2a Examine the regeneration potential of these stands Investigate micro-site and neighborhood characteristics of advanced regeneration Objective 2a - Hypothesis There are more light, nutrients, and moisture available at safe micro-sites where seedlings/ saplings are developing, than other microsites in the stand?cones

4 Objective 2b - DWD Objective 3 Below-Ground Quantify the downed woody debris (DWD) Hypothesis: There will be an increase in DWD from fallen overstory mortality provide insight into standing above-ground Quantify differences in below-ground attributes before, and 1 & 2 yrs after 4 levels of simulated MPB kill and/or forest management in lodgepole pine forests in the western Alberta foothills Microbial biochemical activity (communitylevel-physiological profiling (CLPP)) Nutrient availability Soil characteristics moisture, temperature C pools and susceptibility to fire Objective 3 - Hypothesis With increasing tree mortality there will be a change in: Microbial biochemical activity Nutrient availability Soil moisture Introduction Objectives Outline Methods Preliminary Results Discussion Boreal Canadian Shield Boreal Study Area Mixedwood Foothills Montane / Alpine MPB Aerial Survey Sites Parkland 4

5 STUDY AREA Experimental Treatments Lodgepole pine ~ yrs ( mature ) Medium site index Sandy soils Mid-elevation Control (untreated), Simulated MPB attack (50% overstory kill) Simulated MPB attack (100% overstory kill) Clearcut - harvested to simulate salvage logging management 26 NRH Block Meteorological Towers Repeated Measures Study Each of 4 NRH plots has tower - data continuously recorded. Equipment on the tower includes: Three growing seasons ( 1 yr post-kill ) 2010 ( 2 yr post-kill ) *Trees will be killed in late spring 2009 using Triclopyr herbicide to simulate MPB kill Radiometer Wind direction Wind speed Relative humidity Temperature Plot Design Three Vegetation Blocks Main Plots = 120 x 180 m (2.2 ha) Stand water balance subplot (80 x 80 m; 0.64 ha) Vegetation subplot (80 x 60 m; 0.48 ha) North Ridge Hydro (NRH) Control (undisturbed) 50% MPB kill 4 treatments (below) x 2.2 ha = 8.8 ha total 100% MPB kill Salvage logged (harvested) plot - no trees left standing Power Shack Hill (PSH) * 1 tree height (20m) exterior treated buffer between measurement plots & adjacent stand in all plots Additional replicated vegetation plots = 120 x 100 m (1.2 ha ea) 4 treatments (below) x 2 replicates = 9.6 ha total Vegetation subplot (80 x 60 m; 0.48 ha) Salvage logged (harvested) plot Control (undisturbed) 50% MPB kill 100% MPB kill -- no notrees trees standing left left standing Horse Train Loop (HTL) Note: There is now a large clearcut East of NRH block N 29 Study duration 3 yrs (1 yr pre-treatment, 2 yr. post-treatment) 5

6 Vegetation Plots (0.48 ha) Methods Objective 1: Overstory 19.8-m woody debris transects 10-m x 10-m 80-m 1-m x 1-m understory, LAI- 2000, soil moisture, temp 60-m 4-m radius, shrubs 5 8-m radius (0.02 ha) tree plots, hemispherical photopoints Seedling/sapling neighborhood plots Tree plots (~8-m fixed radius plots O.02 ha) (?5/plot) Species Live status Dbh Ht?Vigor (crown)?stem mapped?tagged follow change including falling?basal area sweeps (BAF4) Hemispherical Photography Leaf Area Index Crown radii (live) Decay class (dead) 2 perpendicular increment cores?subset age radial growth Sapwood thickness (translucence, on-site used to scale canopy leaf area and transpiration ) 32 Hemispherical Photography Leaf Area Index (m 2 /m 2 ) LAI-2000 Photo points revisited after leaf out each year Indirect Site Factor (ISF) to capture changes in cover over time Rapid, non-destructive measurements of LAI Measure at multiple times in the season Early growing season (June) Mid growing season (July) Late growing season (August) Measure at multiple heights: At the forest floor layer Below the tall shrub layer Above the tall shrub layer 34 Methods - Objective 2: Understory Seedlings/Saplings (pine, spruce, balsam) Vascular plants (shrubs, forbs, graminoids) Non-vascular plants (bryophytes, lichens) Woody debris/fuels Data will be collected using PDAs Methods Objective 2: Understory Sampling Protocol Seedlings/sapling - very few on the landscape neighborhood approach?1-m x 1-m quadrats low shrubs, forbs, graminoids, non-vascular plants 4-m radius plots tall shrubs Line-intercept method woody debris

7 Understory Seedlings/Saplings Vegetation Plots (0.48 ha) 1-m x 1-m understory, LAI2000, soil moisture, temp 19.8-m woody debris transects 4-m radius, shrubs 60-m 5 8-m radius (0.02 ha) tree plots, hemispherical photopoints 10-m x 10-m Lodgepole pine Spruce Balsam fir Seedling/sapling neighborhood plots 80-m The Understory Methods - Objective 2: Seedlings/saplings neighborhood approach tagged, GPSed height diameter terminal leader growth # of living branches for each whorl nutrient availability (PRS) soil moisture, temp light free-to-grow competitors (stems within 1.78-m) ht, diameter Very little advanced regeneration currently present Closed cones suggest that seeds are in large supply, but seed predators Damping-off fungi (fungalcaused mortality from germination to just after seedling emergence) that kill seedlings it s not getting warm enough in the absence of fire Bog cranberry (Vaccinium vitis-idaea), moss 39 Club-moss (Lycopodium annonitum) bunchberry (Cornus canadensis) Studded leather lichen (Peltigera aphthosa) 7

8 Labrador tea (Ledum groenlandicum) Green alder (Alnus crispa) Methods - Objective 2: Methods - Objective 2: 1-m x 1-m quadrats Beyond 1-m x 1-m vascular plants Species (?Genus or other grouping for non-vascular) % cover Cover classes (e.g. <1, 1 3, 4 10, 11 25, 26 50, 51 75, >75%) Plant species Bare rock Woody debris (?by decay class) Litter needles, cones Forest floor depth in 4 corners of the quadrat (cm) LAI?hemispherical photos In larger area of the plot identify rare species not captured by the transects/quadrats size (e.g., Kurulok & MacDonald 100-m2 area) time Methods Objective 2b Methods - Objective 2: 4-m radius tall shrub plots (0.05 ha) Down Woody Debris/Fuels Species % cover Cover classes (e.g., <1, 1 3, 4 10, 11 25, 26 50, 51 75, >75%) (Daubenmire - 0-1, 1-5, 5-25, 25-50, 50-75, 75-95, %) Basal diameters of individual woody stems (e.g., green alder) 47 8

9 Methods Objective 2b Down Woody Debris/Fuels Brown s (1971) planar intersect method Total # of transects min. 100 DWD pieces Diameter size classes theoretical amt of time needed to respond to changes in atmospheric moisture (timelag) For each 19.8-m transect: # pieces cm (1-h timelag) cm (10-h timelag) from 1.5 to 3.6 m; # cm (100-h timelag) diameter fuels tallied from 1.5 to 6.1 m fuels > 7.62 cm (1,000-h timelag) tallied from 1.5 to 19.8 m. 1,000-h fuels measure: diameter, decay class (1-5) 49 Methods Objective 3: Below-ground Microbial biochemical activity community-level physiological profiling Nutrient availability (PRS probes) Soil moisture 50 Methods Objective 3: Below-ground Methods Objective 3: CLPP Microbial biochemical activity Community-Level Physiological Profiling (CLPP) Add Soil Sample Microtiter Plate Assays for Each Sample 31 C-substrates with 3 reps /plate One sample per growing season Assess functional diversity of microbes Bacteria Who are they? What are they doing? Incubate 20 C 51 Cleavage of chemical substrates due to enzymatic activities releases purple dye that can be quantified spectrophotometrically CLPP Multivariate Analysis NMS (e.g., bigleaf maple canopy soil vs ground) Methods Objective 3: Below-ground Nutrient Availability PRS Probes - and + ion-exchange resin membranes Nutrient sorption phenomena closely resemble plant root surface Assesses nutrient supply rates by continuously adsorbing charged ionic species over the burial period

10 Nutrient Availability PRS Probes Install (+/-) centered at 10 cm depth in mineral soil Install adjacent to seedlings, and at random 1-m 2 quadrat centers?sampling efficiency have $ for 30/plot/yr Capture growing season in one measurement vs. Early growing season (June mid- July) Later growing season (mid-july Methods Objective 3: Below-ground Soil Moisture Time-domain-reflectrometry (TDR) longterm measurements in all plots systematically (Kevin Bladon taking lead) Spot measurements at each of the 35 1-m 2 quadrats Recorded at least monthly during the growing season September Introduction Objectives Outline Methods Preliminary Results Discussion Preliminary Results - Overstory Basal Area (m2/ha) Basal Area (m2/ha) BA vs Block HTL NRH PSH BAF BA vs Block Block HTL NRH PSH Block Series1 Circular Plots BAF4 Prism Sweeps Basal area at mean plot level ranges from ~30-50 m 2 /ha Preliminary Results - Overstory Preliminary Results - Overstory Mean Basal Area vs Block Mean TPH vs Block Basal Area (m2/ha) HTL NRH PSH Block BAlive BAdead TPH HTL NRH PSH Block tphlive tphdead

11 Preliminary Results - Overstory Tree Count (7.5-m radius plot) vs Block Preliminary Results Overstory Mean DBH vs Block Tree Count (>5 cm dbh) HTL NRH PSH Block countlive countdead Mean dbh (cm) N= HTL NRH PSH dead live Block cm dbh shift from beetle sinks to beetle sources 62 (Safranyik et al. 1974) Basal Area (m2/ha) Preliminary Results - Overstory %kill 50%kill control Mean Basal Area by Block and Treatment salvage 100%kill 50%kill HTL HTL HTL HTL NRH NRH NRH NRH PSH PSH PSH PSH control salvage Block and Treatment 100%kill 50%kill control salvage dbh<25 cm dbh>=25 cm Total Preliminary Results Seedlings/saplings In sampling m radius plots in the three blocks: 23 seedling/saplings: 54/ha ( m tall) 7 PICO seedling/saplings: 17/ha * 11 of the spruce seedling/saplings were in a single plot of HTL 25 cm dbh shift from beetle sinks to beetle sources (Safranyik et al. 1974) Preliminary Observations Understory species census Species tend to be clumped in patches Low diversity of species Introduction Objectives Outline Methods Preliminary Results Discussion

12 Discussion Methods for understory Line intercept vs 1-m x 1-m quadrats Cover classes vs absolute estimates Litter Capturing patchiness of the understory Standardization of methods the ideal scenario! Acknowledgements NSERC Canada Graduate Scholarship Foothills Model Forest Questions? The Line-Intercept Method Cover = (Understory Distance)*100 (Transect Length) 69 Species 3 Species 2 Species 1 Total/Combined 12