Tight coupling of leaf area index to canopy nitrogen and phosphorus across heterogeneous tallgrass prairie communities

Klodd, Anne Elise; Nippert, Jesse B.; Ratajczak, Zak; Waring, H. D.; Phoenix, Gareth K.

doi:10.1007/s00442-016-3713-3

Cited by 6 publications

(7 citation statements)

References 48 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As these examples illustrate, there is no general consensus about what mechanisms control nocturnal transpiration. Mesic grasslands provide an ideal environment to test multiple, potentially interacting drivers of nocturnal transpiration given the range of variation in ecophysiological responses to environmental factors that can exist at small spatial scales (Asbjornsen, Shepherd, Helmers, & Mora, 2008;Klodd, Nippert, Ratajczak, Waring, & Phoenix, 2016;Nippert & Knapp, 2007a;Ocheltree, Nippert, & Prasad, 2013;Tucker, Craine, & Nippert, 2011). The high species richness of mesic grasslands accommodates comparisons among a wide range of species and plant functional groups within the same ecosystem.…”

Section: Introductionmentioning

confidence: 99%

Drivers of nocturnal water flux in a tallgrass prairie

O’Keefe

Nippert

2018

Functional Ecology

Self Cite

View full text Add to dashboard Cite

Nocturnal transpiration can impact water balance from the local community to earth‐atmosphere fluxes. However, the dynamics and drivers of nocturnal transpiration among coexisting plant functional groups in herbaceous ecosystems are unknown. Here, we addressed the following questions: (1) How do nocturnal (Enight) and diurnal (Eday) transpiration vary among coexisting grasses, forbs, and shrubs in a tallgrass prairie? (2) What environmental variables drive Enight and do these differ from the drivers of Eday? (3) Is Enight associated with daytime physiological processes? We measured diurnal and nocturnal leaf gas exchange on perennial grass, forb and woody species in a North American tallgrass prairie. Measurements were made periodically across two growing seasons (May–August 2014–2015) on three C4 grasses (Andropogon gerardii, Sorghastrum nutans and Panicum virgatum), two C3 forbs (Vernonia baldwinii and Solidago canadensis), one C3 sub‐shrub (Amorpha canescens) and two C3 shrubs (Cornus drummondii and Rhus glabra). By extending our study to multiple functional groups, we were able to make several key observations: (1) Enight was variable among co‐occurring plant functional groups, with the highest rates occurring in C4 grasses, (2) Enight and Eday exhibited different responses to vapour pressure deficit and other environmental drivers, and (3) rates of Enight were strongly related to predawn leaf water potential for grasses and woody species, and were likely modulated by small‐scale changes in soil moisture availability. Our results provide novel insight into an often‐overlooked portion of ecosystem water balance. Considering the high rates of Enight observed in C4 grasses, as well as the widespread global occurrence of C4 grasses, nocturnal water loss might constitute a greater proportion of global evapotranspiration than previously estimated. Additionally, future predictions of nocturnal water loss may be complicated by stomatal behaviour that differs between the day and at night. Finally, these data suggest a water‐use strategy by C4 grasses wherein the high rates of Enight occurring during wet periods may confer a competitive advantage to maximize resource consumption during periods of greater availability. A http://onlinelibrary.wiley.com/doi/10.1111/1365-2435.13072/suppinfo is available for this article.

show abstract

Section: Introductionmentioning

confidence: 99%

Drivers of nocturnal water flux in a tallgrass prairie

O’Keefe

Nippert

2018

Functional Ecology

Self Cite

View full text Add to dashboard Cite

show abstract

“…For example, Zechmeister-Boltenstern et al (2015) synthesized the stoichiometry in different ecosystem compartments and highlighted the latitudinal gradients of plant, litter, and soil stoichiometry. Liu et al (2017) evaluated soil net N mineralization among different ecosystems at the global scale and found that net N mineralization decreased with increasing latitude. They also found that the N mineralization at higher latitudes is more sensitive to temperature changes than at lower latitudes, indicating potential alleviation of N limitation for plants' productivity at boreal regions under global warming.…”

Section: Introductionmentioning

confidence: 99%

GOLUM-CNP v1.0: a data-driven modeling of carbon, nitrogen and phosphorus cycles in major terrestrial biomes

et al. 2018

View full text Add to dashboard Cite

Abstract. Global terrestrial nitrogen (N) and phosphorus (P) cycles are coupled to the global carbon (C) cycle for net primary production (NPP), plant C allocation, and decomposition of soil organic matter, but N and P have distinct pathways of inputs and losses. Current C-nutrient models exhibit large uncertainties in their estimates of pool sizes, fluxes, and turnover rates of nutrients, due to a lack of consistent global data for evaluating the models. In this study, we present a new model–data fusion framework called the Global Observation-based Land-ecosystems Utilization Model of Carbon, Nitrogen and Phosphorus (GOLUM-CNP) that combines the CARbon DAta MOdel fraMework (CARDAMOM) data-constrained C-cycle analysis with spatially explicit data-driven estimates of N and P inputs and losses and with observed stoichiometric ratios. We calculated the steady-state N- and P-pool sizes and fluxes globally for large biomes. Our study showed that new N inputs from biological fixation and deposition supplied >20 % of total plant uptake in most forest ecosystems but accounted for smaller fractions in boreal forests and grasslands. New P inputs from atmospheric deposition and rock weathering supplied a much smaller fraction of total plant uptake than new N inputs, indicating the importance of internal P recycling within ecosystems to support plant growth. Nutrient-use efficiency, defined as the ratio of gross primary production (GPP) to plant nutrient uptake, were diagnosed from our model results and compared between biomes. Tropical forests had the lowest N-use efficiency and the highest P-use efficiency of the forest biomes. An analysis of sensitivity and uncertainty indicated that the NPP-allocation fractions to leaves, roots, and wood contributed the most to the uncertainties in the estimates of nutrient-use efficiencies. Correcting for biases in NPP-allocation fractions produced more plausible gradients of N- and P-use efficiencies from tropical to boreal ecosystems and highlighted the critical role of accurate measurements of C allocation for understanding the N and P cycles.

show abstract

“…Finally, we assumed that LAI and CAI were constant throughout the growing season. While these parameters likely increase with plant growth throughout the season (Klodd et al, ), we did not have continuous high temporal resolution estimates of LAI or CAI and instead used species‐averaged estimates.…”

Section: Discussionmentioning

confidence: 99%

“…Finally, E L was scaled to E C with the following equation:

E_{C} = E_{L} A_{L} {A_{s}}^{- 1}

where A L is the leaf area index (LAI) and A s is the conducting tissue area index (CAI). LAI data for grasses, forbs, and small shrubs ( A. canescens and R. glabra ) were taken from previous work at this site (Klodd et al, ; J. Nippert, unpublished). LAI was measured in 2015 for C. drummondii with a LAI meter (LiCor, Inc, Lincoln, NE, USA).…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Bridging the Flux Gap: Sap Flow Measurements Reveal Species‐Specific Patterns of Water Use in a Tallgrass Prairie

et al. 2020

Self Cite

View full text Add to dashboard Cite

Predicting the hydrological consequences following changes in grassland vegetation type (i.e., woody encroachment) requires an understanding of water flux dynamics at high spatiotemporal resolution for predominant species within grassland communities. However, grassland fluxes are typically measured at the leaf or landscape scale, which inhibits our ability to predict how individual species contribute to changing ecosystem fluxes. We used external heat balance sap flow sensors and a hierarchical Bayesian state‐space modeling approach to bridge this “flux gap” and estimate continuous species‐level water flux in common tallgrass prairie species. Specifically, we asked the following: (1) How do diurnal and nocturnal water fluxes differ among woody and herbaceous plants? (2) How sensitive are woody and herbaceous species to environmental drivers of diurnal and nocturnal water flux? We highlight three results: (1) Cornus drummondii, the primary woody encroacher in this grassland, exhibited the greatest canopy‐level water loss; (2) nocturnal transpiration was a large component of the water lost in this ecosystem and was driven primarily by C4 grasses and C. drummondii; and (3) the sensitivity of canopy transpiration to environmental drivers varies among plant functional types and throughout a 24‐hr period. Our data reveal important insights regarding the water use strategies of woody versus herbaceous species in tallgrass prairies and about the potential hydrological consequences of ongoing woody encroachment. We suggest that the high, static flux rates observed in woody species will likely deplete deep water stores over time, potentially creating hydrological deficits in grasslands experiencing woody encroachment and concomitantly increasing the vulnerability of these ecosystems to drought.

show abstract

Tight coupling of leaf area index to canopy nitrogen and phosphorus across heterogeneous tallgrass prairie communities

Cited by 6 publications

References 48 publications

Drivers of nocturnal water flux in a tallgrass prairie

Drivers of nocturnal water flux in a tallgrass prairie

GOLUM-CNP v1.0: a data-driven modeling of carbon, nitrogen and phosphorus cycles in major terrestrial biomes

Bridging the Flux Gap: Sap Flow Measurements Reveal Species‐Specific Patterns of Water Use in a Tallgrass Prairie

Contact Info

Product

Resources

About