MétaCan
Menu
Back to cohort

Why are annual plants rarely spring ephemerals?

2000· article· en· W1935315140 on OpenAlexaff
Margaret F. Mckenna, Gilles Houle

Bibliographic record

VenueNew Phytologist · 2000
Typearticle
Languageen
FieldEnvironmental Science
TopicPlant Water Relations and Carbon Dynamics
Canadian institutionsUniversité Laval
Fundersnot available
KeywordsPhenologyCanopyBiomass (ecology)UnderstoryDeciduousBiologyAnnual plantShadingAgronomyLight intensityEnvironmental scienceHorticultureBotany

Abstract

fetched live from OpenAlex

The period of active growth for spring ephemeral plants coincides with the period of high light, water and nutrient availability between snow melt and canopy closure in the understorey of deciduous forests in eastern North America. However, low temperatures prevail during this period and might restrict the performance of these plants. Remarkably, this peculiar phenology is extremely rare among annual plants. To understand better the role of light and water availability and of temperature in the phenology of spring ephemeral plants, we investigated the effects of two temperature regimes (low: 16/7 °C and high: 21/14 °C), three water availability levels (saturated, control and drought), and three photosynthetically active photon flux densities: low (85–100 μmol m −2 s −1 ); intermediate (182–196 μmol m −2 s −1 ); high (437–454 μmol m −2 s −1 ) on the growth and reproduction of the annual Floerkea proserpinacoides . Total biomass, total leaf area and flower and seed production increased with increasing temperature, water availability and light intensity. Total leaf area and total biomass were reduced in plants that were stressed under drought. However, at high temperatures, this reduction was less pronounced when droughted plants were partially shaded. At low temperatures, plants began to senesce after approximately 9 wk, whereas at higher temperatures, signs of senescence appeared after only 7 wk of growth. Despite shorter longevity, total biomass was approximately 1.5 times higher in the control water treatment at higher than at lower temperatures as a result of greater above‐ground growth, and plants allocated a significantly greater proportion of mass gain to seed production. Although F. proserpinacoides can tolerate low temperatures such as those typical of early spring, higher temperatures such as those of late spring/early summer are more favorable for growth and reproduction as long as water and light are not limiting. Spring ephemeral annuals might be rare because low temperatures reduce growth rate and extend the life cycle. An annual plant might not have time to reproduce before resource availability deteriorates with canopy closure unless reproduction begins early in the life cycle of the species.

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.

How this classification was reachedexpand

Full frame distilled prediction

Teacher imitation

Not calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.

metaresearch head score (Codex)0.000
metaresearch head score (Gemma)0.000
Version: codex-gemma-dda1882f352aValidation status: machine_predicted_unvalidated
Candidate categoriesInsufficient payload (model declined to judge)
Consensus categoriesInsufficient payload (model declined to judge)
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Observational · Consensus signal: none
GenreCandidate signal: Empirical · Consensus signal: Empirical
Teacher disagreement score0.479
Threshold uncertainty score1.000

Codex and Gemma teacher scores by category

CategoryCodexGemma
Metaresearch0.0000.000
Meta-epidemiology (narrow)0.0000.000
Meta-epidemiology (broad)0.0000.000
Bibliometrics0.0000.000
Science and technology studies0.0000.000
Scholarly communication0.0000.000
Open science0.0000.000
Research integrity0.0000.000
Insufficient payload (model declined to judge)0.0040.001

Machine scores (provisional)

The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.

Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.

Opus teacher head0.011
GPT teacher head0.214
Teacher spread0.202 · how far apart the two teachers sit on this one work
Validation statusscore_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it

Classification

machine, unvalidated

Machine predicted; both teacher heads agree on what is shown here.

Study designObservational
Domainnot available
GenreEmpirical

How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".

Quick stats

Citations50
Published2000
Admission routes1
Has abstractyes

Explore more

Same venueNew PhytologistSame topicPlant Water Relations and Carbon DynamicsFrench-language works237,207