Ecology Lab WETLANDS COMMUNITY THEORY GRASSLANDS OTHER FORESTS BRYOPHYTES. Steve Henstra Glen Porter Alison Campbell

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1 WETLANDS Steve Henstra Glen Porter Alison Campbell GRASSLANDS Robbie Lee FORESTS Scott Black Kaeli Stark Gary Lewis Tania Perzoff Andre Arsenault Andrea Lawson Rosemary Mason Daniel Gagnon Bradfield Plant Ecology Lab BRYOPHYTES Kella Sadler Lyn Baldwin Pat Williston Norm Kenkel Research examples from my lab COMMUNITY THEORY Elizabeth Binney Alfred Brulisauer Paul Drewa OTHER Eduardo Jovel Shannon Hagerman Stephan Kesting Qiwei Liang Bob Bandringa John Binns Nick Page Eva Downarowicz

2 Gary the early years to conifer forests From coastal marshes

3 What s going on? Stability: the capacity for communities to persist in the same state after disturbance Community assembly: deterministic vs stochastic processes, role of the seedbank, etc. Vegetation-environment relationships: tidal flooding, soil, climate

4 PCA application: intertidal marsh creation at the Campbell River estuary

5 PCA application: intertidal marsh creation at the Campbell River estuary

6 Experimental design 4 islands 23 transects planted vs unplanted 1m vs.5m spacing 1981 Vegetation monitoring Island construction

7 Conceptual model Range of Natural Variability Apparent Range Of Variability Management Target Present Condition [Source: Wong, C., & K. Iverson. 2003]

8 Conceptual model PCA 2 Full range of variability in coastal marshes Apparent range of variability at CR Management Target (after X years) 1982 veg plugs PCA 1

9 Early planting success on Island

10 Longer term success on Island

11 Also some concerns Island 3 (low elev.) Island 1 (Carex dieback)

12 Aerial view of dieback zones

13 Plant community dynamics Nunn s Island PCA trajectories of transects Species richness Vegetation cover Mid marsh Low Marsh (Target) Island 1 Island 3 Island 2 Island 4

14 Summary of Coastal Conceptual model Marsh Research Range of Natural Variability Apparent Range Of Variability Management Target [Wong, C., & K. Iverson ] Present Condition

15 Summary of Coastal Conceptual model Marsh Research We re getting there Range of Natural Variability Apparent Range Of Variability Management Target Present Condition

16 PCA application: bryophyte community dynamics Most forest floor bryophyte associations are transient

17 PCA application: bryophyte community dynamics General Question: Do forest floor bryophyte communities show transience? Community-unit Low TAD (strong V-E coupling) Individualistic High TAD (weak V-E coupling) Environmental gradient

18 PCA application: bryophyte community dynamics Unstable - slope >25 o - small twigs & branches Forest floor stability gradient Stable - slope <25 o - compressed needles Q: How measure transience?

19 Conceptual model PCA 2 A microplots plot (400m 2 ) Within-plot bryophyte heterogeneity A > B B PCA 1

20 Conceptual model PCA 2 A microplots bryophytes B environment Strong V-E coupling (low TAD) PCA 1

21 Conceptual model PCA 2 A Weak V-E coupling (high TAD) B PCA 1

22 PCA application: bryophyte community dynamics Steps in data analysis Divide plots into 2 groups based on environmental (microhabitat) stability. Use PCA to calculate within-plot heterogeneity. Do separately for bryophyte vegetation (V) and environment (E). Compare V-E for the 2 stability groups: - strong V-E => low transience - weak V-E => high transience

23 PCA application: bryophyte community dynamics PCA environment 3 PCA bryophytes 20 stable 2 unstable symbols show 400m 2 study plots symbol size indicates degree of heterogeneity for each plot

24 PCA application: bryophyte community dynamics stable r 2 =0.25 p=0.01 (low transience) Log Bryo Area unstable r 2 =0.03 p=0.49 (high transience) Log Env Area symbols show 400m 2 study plots Conclusion: TAD may be an important community structuring mechanism