Jennifer L. Baltzer

Wilfrid Laurier University

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Trends

Author Order

Document Type

Co-Authors

M. R. Turetsky

Institute of Arctic and Alpine Research

Jill F. Johnstone

University of Alaska Fairbanks

Michelle C. Mack

Northern Arizona University

Nicola J. Day

Victoria University of Wellington

Xanthe J. Walker

Northern Arizona University

Oliver Sonnentag

Université de Montréal

Brendan M. Rogers

Woodwell Climate Research Center

W. L. Quinton

Wilfrid Laurier University

S. J. Goetz

Northern Arizona University

Steven G. Cumming

Université Laval

Cooperative Institutions

ForestGEO

104

Ecological Society of America

John Wiley & Sons (United States)

National Museum of Natural History

Universiti Brunei Darussalam

Chinese Academy of Sciences

Smithsonian Tropical Research Institute

Centre National de la Recherche Scientifique

University of Alberta

Wageningen University & Research

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Field

Carbon and nitrogen cycling dynamics following permafrost thaw in the Northwest Territories, Canada

The Science of The Total Environment (2022)

Catherine M. Dieleman Nicola J. Day Jean Holloway Jennifer L. Baltzer Thomas A. Douglas

Biogeochemical Cycle

Soil carbon

Carbon fibers

Chronosequence

10.1016/j.scitotenv.2022.157288

Cite

Citations (4)

The impact of flower harvesting on seedling recruitment in sea lavender (Limonium carolinianum, Plumbaginaceae)

Rhodora (2002)

Jennifer L. Baltzer Heather L Hewlin E. G. Reekie Peter Taylor J. Sherman Boates

Flowers of Limonium carolinianum are harvested for use in dried flower arrangements and various crafts. The increasing commerciali zation of this harvest has led to concerns regarding its sustainability. We quantified the extent of the harvest on four marshes on the Bay of Fundy coast of Nova Scotia, Canada. Over a four-year period from 1996 to 1999, flower stalk removal averaged 32% on easily accessible portions of these marshes (i.e., within 100 m of a road) compared to 5% on inaccessible por tions (greater than 500 m from a road). In 5 X 5 m plots where flowers were experimentally removed, no seedlings emerged the following year, whereas seedlings always emerged in unpicked control plots. This rapid and dramatic impact of localized harvesting on seedling emergence is due to the limited dispersal and short life span of L. carolinianum seeds. Sampling in concentric circles around isolated adults revealed that 50% of seedlings emerged within 34 cm of the parent and 90% emerged within 61 cm. Tethered seed experi ments revealed that seeds that did not germinate in the first spring after pro duction did not survive to the next spring. Our results suggest that unregu lated harvesting has the potential to dramatically impact recruitment into local populations. To reduce the likelihood of local extinction we recommend that harvesters do not reduce flower stalk densities below 1 per m2.

Stalk

Source

Cite

Citations (4)

Appendix D. Tables showing most significant principal components of principal components analyses of climate data, with figure showing change in climate parameters over the past 60 years.

Figshare (2016)

Katie E. Marshall Jennifer L. Baltzer

Tables showing most significant principal components of principal components analyses of climate data, with figure showing change in climate parameters over the past 60 years.

10.6084/m9.figshare.3561432

Cite

Citations (0)

Appendix E. Table showing most significant principal components of principal components analysis of tree stand data, and figures showing relationship of tree stand characteristics with species richness.

Figshare (2016)

Katie E. Marshall Jennifer L. Baltzer

Table showing most significant principal components of principal components analysis of tree stand data, and figures showing relationship of tree stand characteristics with species richness.

Table (database)

Tree (set theory)

10.6084/m9.figshare.3561429

Cite

Citations (0)

ABoVE: Characterization of Carbon Dynamics in Burned Forest Plots, NWT, Canada, 2014

ORNL DAAC (2019)

Xanthe J. Walker Jennifer L. Baltzer W. Laurier Steven G. Cumming Nicola J. Day

Carbon fibers

10.3334/ornldaac/1664

Cite

Citations (3)

Why do mosses have height? Moss production as a tragedy of the commons game

Evolutionary ecology research (2016)

Gordon G. McNickle Cory A. Wallace Jennifer L. Baltzer

Source

Cite

Citations (2)

Scale‐dependent responses of understory vegetation to the physical structure of undisturbed tundra shrub patches

Ecosphere (2022)

Cory A. Wallace Jennifer L. Baltzer

Abstract Much of the Arctic is experiencing rapid change in the productivity and recruitment of tall, deciduous shrubs. It is well established that shrub expansion can alter tundra ecosystem composition and function; however, less is known about the degree to which variability in the physical structure of shrub patches might mediate these changes. There is also limited information as to how different physical attributes of shrub patches may covary and how they differ with topography. Here, we address these knowledge gaps by measuring the physical structure, abiotic conditions, and understory plant community composition at sampling plots within undisturbed green alder patches at a taiga–tundra ecotone site in the Northwest Territories, Canada. We found surprisingly few associations between most structural variables and abiotic conditions at the plot scale, with the notable exceptions of canopy complexity and snow depth. Importantly, neither patch structure nor abiotic conditions were associated with the vegetation community at the plot scale when among‐patch variation was accounted for. However, among‐patch variation in plant community composition was significant and represented a gradient in the richness of tundra specialists and Sphagnum moss abundance. This gradient was strongly associated with mean patch snow depth, which was likely controlled at least in part by mean patch canopy complexity. Overall, natural variability in green alder patch structure had less of an association with abiotic conditions than expected, suggesting future changes in physical structure at undisturbed sites may have limited environmental impact at the plot scale. However, at the patch scale, increases in snow depth, likely related to canopy complexity, were negatively associated with tundra specialist richness, potentially due to phenological limitations associated with shortened growing seasons. In summary, our data suggest emergent properties exist at the patch scale that are not apparent at the plot scale such that plot‐scale measurements do not represent variation in understory community composition across the landscape. The results presented here will inform future work addressing spatial variability in shrub impacts on ecosystem function and increase our understanding of understory community variation within alder patch habitats at the taiga–tundra ecotone.

Ecotone

Understory

10.1002/ecs2.4218

Cite

Citations (1)

Determinants of whole‐plant light requirements in Bornean rain forest tree saplings

Journal of Ecology (2007)

Jennifer L. Baltzer Sean C. Thomas

1 Shade tolerance, defined as the ability to survive and grow under low light, varies markedly among tree species. However, the role of low-light growth responses in determining shade tolerance is unclear, as are the effects of non-light resources such as soil nutrients. 2 A conceptually simple field measure of shade tolerance is the whole-plant light compensation point (WPLCP), evaluated as the x-intercept of the relationship between growth and incident light integrated over a long time interval. Here we compare WPLCP for growth and survivorship of saplings of Bornean tree species differing in shade tolerance, and evaluate the importance of various physiological and morphological traits in predicting WPLCP. We also examine both phenotypic and evolved differences in WPLCP between tree saplings growing on two distinct soil types at Sepilok Forest Reserve, Sabah, Malaysia. 3 Growth-based estimates of WPLCP showed essentially a 1 : 1 correspondence to threshold light levels for survivorship. At higher light, more light-demanding species showed higher growth, resulting in a steeper slope of the relationship between relative growth rate (RGR) and light availability than in more shade-tolerant species. This resulted in significant crossovers in the RGR–light relationship among species. 4 Dark respiration (Rd) was the single best predictor of WPLCP; other leaf traits such as leaf nitrogen and photosynthetic capacity were correlated with, but excluded as predictors of, WPLCP in multiple regression analyses. 5 Although soil type had no consistent phenotypic effect on WPLCP, evolved responses among species were pronounced: species associated with the nutrient-poor, drought-prone, sandstone-derived soils had higher WPLCP values than alluvial soil specialists in phylogenetically controlled comparisons. 6 Our results indicate that minimum light levels for growth do not diverge from those for survivorship, and do not support the view that low-light survivorship solely determines shade tolerance. Our analyses also suggest that Rd is the strongest determinant of whole-plant light requirements in tropical tree saplings, and thus may be an easily measured surrogate of WPLCP and shade tolerance. 7 Prediction of tree species resource requirements is crucial for understanding forest dynamics and promoting ecology-based forest management and restoration, particularly in diverse tropical forests where data on the resource requirements of most species are not available. Easily measured surrogates of resource requirements (e.g. Rdas a predictor of shade tolerance) will contribute to this goal, as will an improved understanding of the interactive effects of multiple resources on tree performance.

Shade tolerance

Specific leaf area

Compensation point

10.1111/j.1365-2745.2007.01286.x

Cite

Citations (159)

Permafrost condition determines plant community composition and community‐level foliar functional traits in a boreal peatland

Ecology and Evolution (2021)

Katherine M. Standen Jennifer L. Baltzer

Boreal peatlands are critical ecosystems globally because they house 30%-40% of terrestrial carbon (C), much of which is stored in permafrost soil vulnerable to climate warming-induced thaw. Permafrost thaw leads to thickening of the active (seasonally thawed) layer and alters nutrient and light availability. These physical changes may influence community-level plant functional traits through intraspecific trait variation and/or species turnover. As permafrost thaw is expected to cause an efflux of carbon dioxide (CO

Dominance (genetics)

Plant functional type

Mesocosm

10.1002/ece3.7818

Cite

Citations (15)

Checkerboard score–area relationships reveal spatial scales of plant community structure

Oikos (2017)

Gordon G. McNickle Eric G. Lamb Thomas Michael Lavender James F. Cahill Brandon S. Schamp

Identifying the spatial scale at which particular mechanisms influence plant community assembly is crucial to understanding the mechanisms structuring communities. It has long been recognized that many elements of community structure are sensitive to area; however the majority of studies examining patterns of community structure use a single relatively small sampling area. As different assembly mechanisms likely cause patterns at different scales we investigate how plant species co‐occurrence patterns change with sampling unit scale. We use the checkerboard score as an index of species segregation, and examine species C‐score1–sampling area patterns in two ways. First, we show via numerical simulation that the C‐score–area relationship is necessarily hump shaped with respect to sample plot area. Second we examine empirical C‐score–area relationships in arctic tundra, grassland, boreal forest and tropical forest communities. The minimum sampling scale where species co‐occurrence patterns were significantly different from the null model expectation was at 0.1 m 2 in the tundra, 0.2 m 2 in grassland, and 0.2 ha in both the boreal and tropical forests. Species were most segregated in their co‐occurrence (maximum C‐score) at 0.3 m 2 in the tundra (0.54 3 0.54 m quadrats), 1.5 m 2 in the grassland (1.2 3 1.2 m quadrats), 0.26 ha in the tropical forest (71 3 71 m quadrats), and a maximum was not reached at the largest sampling scale of 1.4 ha in the boreal forest. The most important finding is that the dominant scales of community structure in these systems are large relative to plant body size, and hence we infer that the dominant mechanisms structuring these communities must be at similarly large scales. This provides a method for identifying the spatial scales at which communities are maximally structured; ecologists can use this information to develop hypotheses and experiments to test scale‐specific mechanisms that structure communities.

Quadrat

10.1111/oik.04620

Cite

Citations (24)