Presentation to Department of Environmental and Forest Biology at the State University of New York College of Environmental Science and Forestry, fall 2011. **Results are preliminary and unpublished**

1. Constructed vernal pools in
southwestern New York State
Jaime Jones
1 December 2011

2. Outline
• Overview- study system, sites, objectives
• Methods- sampling scheme, data collected
• Summary statistics- abiotic characteristics, total cover
• NMS ordination (briefly)
• MRPP & Indicator Species Analysis
• Modeling cover- correlations, Generalized Linear Model

3. Vernal pools in the northeast
• Small, isolated, “temporary” wetlands (Colburn 2004)
• Important for obligate/facultative VP animals & plant species of
concern (Comer et al. 2005)
– Carex lupuliformis- false hop sedge (S2)
– Hottonia inflata- featherfoil (S2)
– Scirpus ancistrochaetus- northeastern bulrush (E)
• Recently rediscovered in New York state in county adjacent to study sites!
• Loss of topographic heterogeneity = loss of pools
Natural pool Created pool (circa 1970)

4. Upper Susquehanna Coalition
Network of soil &
water conservation
districts
Constructed 300+
pools in Schuyler,
Chemung, and
Tompkins counties
(2003-2010)

5. 2007 2007
Photos taken summer 2010
2003
2008 2006
2006
60 “new” (2003-2008; USC)
+ 10 “old” (circa 1970; DEC) (all forest)
n= 70 “created” pools

6. Objectives
1. Describe, quantify, and compare vascular plant
assemblages in created and natural vernal pools
2. Investigate the relative influence of selected
environmental factors on vascular plant diversity,
composition, and cover in created vernal pools
3. Describe pool designs and construction methods that
facilitate establishment of desired plant species.

7. Sampling Design
Pool selection:
• Random (within each of
8 properties)
Vegetation sampling:
Stratified by region of pool:
• Edge
• Interior
Vegetation data:
• Cover by species (%)
• Total cover (%)

8. Predictor variables
Abiotic variables Biotic variables
• Pool age (months) • Total basal area
• Light: Percent full sun (%) • Tree species richness
– Average and range
• Terrestrial vegetation
• Hydrology – Cover by species (%)
– Depth: max, min, residual (%) –Total cover (%)
– Area: max, min, residual (%) – Species richness
• Water chemistry • Bryophyte cover (%)
– Specific conductivity
• CWD cover (%)
– pH
• Slope of pool margins
• Soils (n=30 created pools)
– Bulk density
– Organic matter (%)

9. Light boxplot
n=10 n=17 n=43

10. Residual pool

11. Soils
(n=30 USC-created pools)
------------ Root-restrictive Db
in clay
3.3 to 21.95% 0.57 to 1.53 g/cm3

12. Objective 1:
Describe & quantify vascular plant assemblages-
Total cover
• Hypothesis: Average total cover will range widely
among pools, from 0% to nearly 100%.
– Forest pools with dense canopy cover will be sparsely vegetated,
and open-canopy pools will be densely vegetated.

13. Total cover boxplot

14. Mean total cover of natural andcover vernal pools
Mean total created
Created(old) Created(new)open Created(new)forest Natural
Origin

15. Objective 1 (cont’d):
Describe and quantify vascular plant assemblages-
Species composition
• Hypothesis: Species composition will be dominated by native
FACW / OBL species.
– Open-canopy pools: Common FACW / OBL graminoids & Typha spp.
– Forest pools: Common herbaceous/woody FACW / OBL species
• NMS ordination
• MRPP- Multi-Response Permutation Procedure
• Indicator Species Analysis

16. Nonmetric Multidimensional Scaling
(NMS) Ordination
• Ordination: Similar objects (pools) are
near each other and dissimilar objects
(pools) are farther from each other
• NMS ordination:
• Nonparametric multivariate technique
• Indirect gradient analysis

17. NMS: Created pools in species space
Stress= 18.94, instability <0.00001
Juncus tenuis, Scirpus cyperinus, Solidago
canadensis, Scirpus atrovirens, Eleocharis ovata,
Juncus effusus, Euthamia graminifolia

18. Multi-Response Permutation Procedure
(MRPP)
• Ho: No significant difference in species composition
between 2+ a priori groups
• Nonparametric test
• Products: Test statistic, p-value, and measure of effect size (“A”)
– A = “Chance-corrected within-group agreement”
If Then
All items identical within A=1
groups (Δ=0)
Heterogeneity within A=0
groups = random
Heterogeneity within A<0
groups > random

19. MRPP Analysis
• Rank-transformed, Sorenson distance measure
– Old, forest pools
– New, forest pools
– New, open canopy pools
– Natural pools
• A= 0.353, p=0.0000000
• Pairwise comparisons (A>0.3, p≈0.00000):
Pool type 1 Pool type 2 A
New, open Old, forest 0.4387
New, open Natural 0.4258
Old, forest Natural 0.3422

20. Indicator Species Analysis
• Identifies species that are indicative of a priori groups
• Indicator Value: Percent of perfect indication
– Based on relative abundance & relative frequency
• “Perfect” indicator species (I.V. = 100) is
– Faithful (always present in its group)
– Exclusive (never present in other groups)

21. ISA: Natural, old forest, new forest, & new open pools
(top 6 indicator species)
Group Species WIS Native IV p Others
Osmunda regalis OBL Y 57.1 0.0002 -
Carex intumescens FACW+ Y 56.0 0.0002
Natural
Quercus rubra FACU- Y 47.8 0.0004
Maianthemum canadense FAC- Y 33.5 0.0074
Agrostis canina FACU Y 50.0 0.0002 Leersia
oryzoides,
Galium asprellum OBL Y 50.0 0.0002
Cornus
Created, old, Lycopus uniflorus OBL Y 41.5 0.0096 amomum
forest Populus tremuloides ? Y 39.5 030024
Bidens connata FACW+ Y 35.2 0.014
Amelanchier arborea FAC- Y 34.6 0.0044
Created, Oxalis dillenii ? Y 33.4 0.0502 -
new, forest
Typha latifolia OBL Y 70.4 0.0002 Euthamia
graminifolia,
Juncus tenuis FAC- Y 69.1 0.0002
Eleocharis
Created, Juncus effusus FACW+ Y 68.1 0.0002 ovata,
new, open Potentilla simplex FACU- Y 68.1 0.0002 Scirpus
atrovirens,
Panicum virgatum FAC Y 64.7 0.0002 Scirpus
Carex scoparia FACW Y 64.0 0.0002 cyperinus…

22. Forest
Natural
Open
Photos: plants.usda.gov, florida.plantatlas.usf.edu, & calphotos.berkeley.edu

23. Objective 2: Environmental influences on-
Species composition
• Hypothesis: Strongest influences on species
composition will be light availability and drawdown
(minimum depth/ minimum area/ residual pool)
• NMS ordination: Joint plot with environmental factor
overlay
Future analysis: Logistic models for presence/absence
of selected species

24. NMS: Created pools in species space
Stress= 18.94, instability <0.00001
light, terrestrial veg. cover, basal area,
tree diversity, pH

25. Objective 2 cont’d: Environmental influences on-
Total cover
• Hypothesis: Strongest influences on total vascular plant
cover will be Light availability and drawdown
• Generalized Linear Model (GLM) of cover
– Negative binomial distribution (overdispersed data)
– Akaike Information Criterion (AIC)

27. Selecting variables for model fitting
• Highly correlated and/or proxy variables
– e.g. light availability and total basal area
• Used variable most strongly correlated with
total cover
• Pool age was not included

28. Model simplification
2
Light pH Cond Mar.Slope Light*pH pH*Cond AIC Pseudo -r
1 x x x 512.75 0.36
2 x x 513.01 0.34
3 x x x x 513.97 0.36
4 x x x 514.79 0.34
5 x x x x x 515.29 0.37
6 x 516.26 0.28
• Top candidate models include:
– Light
– pH of water
– Light*pH interaction
• No pool size or drawdown variables

29. Simple Generalized Linear Models of cover
AIC=516.26 AIC=527.32

30. GLM of cover: Including soil data
• No correlation of Db or %OM with total cover
• No effect on model fit
• Range of values too narrow?

31. Future Analyses
• Regression models
(potentially mixed models; random effect = property):
– Species richness
– Species diversity
– Proportion of non-natives
– Presence/absence of species of interest (e.g. Typha
spp., Carex lupuliformis, etc.)
• ANOVA to compare various characteristics
among different types of pools

32. Comparing diversity and richness:
– Much larger total area sampled for created pools
than for natural pools
– Need to account for this difference. Thoughts?
Grouping Pool Type n Area (m2)
All Natural Natural 7 1695
All Created Created, all 70 4092
Created, by Created, open 43 1660
canopy Created, forest 27 2432
Created, by Created, new, open 43 1660
canopy & Created, new, forest 17 1067
age
Created, old, forest 10 1365

33. Seed bank study
• Composite soil samples, n=15 created pools
• Seedling emergence method (van der Valk and Davis 1978,
Smith and Kadlec 1983, Haukos and Smith 1993)
• Transplants- playing the waiting game (and when it’s time
to quit playing)
Gratiola neglecta
Carex spp., Gnaphalium uliginosum,
Solidago sp., various dicotyledons

34. Acknowledgements
• Don Leopold- major professor
• James Gibbs, John Stella- committee members
• Upper Susquehanna Coalition
• Edna Bailey Sussman Foundation- funding
• Wetland Foundation- funding
• Property owners
• Jessica Logan- 2010 field assistant
• Ecolunch & 401 Illick folks
Larval salamander Utricularia sp. Caddisfly larva