Some information obtained from diurnal pattern of sap flow

Abstract. Tree canopies are known to emit large amounts of VOCs (volatile organic compounds) such as monoterpenes to the surrounding air. The main source for these is considered to be the green biomass, i.e. foliage, but emissions from the woody compartments have not been quantified. A VOC emission anomaly has been observed during transition from winter to summer activity. We analyzed if non-foliar components could partially explain the anomaly. We measured the VOC emissions from Scots pine (Pinus sylvestris L.) stems and shoots during the dehardening phase of trees in field conditions in two consecutive springs. We observed a large, transient monoterpene burst from stems, while the shoot monoterpene emissions and transpiration remained low. The burst lasted about 12 h. Simultaneously, an unusual night-time sap flow and an anomalous diurnal pattern of tree diameter were detected. Hence, we suggest that the monoterpene burst was a consequence of the recovery of the stem from winter-time. This indicates that the dominant processes and environmental drivers triggering the monoterpene emissions are different between stems and foliage.

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Pruning effects on sap flow and sugar phloem unloading in current-year shoots of different aged grapevine shoots

Pakistan Journal of Botany ◽

10.30848/pjb2021-3(9) ◽

2020 ◽

Vol 53 (3) ◽

Author(s):

Xianhua Zhao ◽

Liyuan Liu ◽

Hua Li ◽

Cuixia Li

Keyword(s):

Sap Flow ◽

Phloem Unloading

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Diurnal pattern of insulin requirements in insulin-dependent diabetics

Scandinavian Journal of Clinical and Laboratory Investigation ◽

10.3109/00365518209168051 ◽

1982 ◽

Vol 42 (1) ◽

pp. 63-68 ◽

Cited By ~ 9

Author(s):

E. R. Mathiesen ◽

P. Rubin ◽

J. Sandahl Christiansen ◽

P. Aaby Svendsen ◽

T. Lauritzen ◽

...

Keyword(s):

Diurnal Pattern ◽

Insulin Requirements ◽

Insulin Dependent

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Salivary C-reactive protein among at-risk adolescents: A methods investigation of out of range immunoassay data

10.31234/osf.io/w9hga ◽

2018 ◽

Author(s):

Elizabeth Landau ◽

John Arthur Trinder ◽

Julian Simmons ◽

Monika Raniti ◽

Matthew Blake ◽

...

Keyword(s):

At Risk ◽

Temporal Stability ◽

Management Technique ◽

Clinical Settings ◽

Diurnal Pattern ◽

C Reactive Protein ◽

Reactive Protein ◽

Treatment Techniques ◽

Salivary Biomarker ◽

At Risk Adolescents

Inflammatory markers including C-Reactive Protein (CRP) are increasingly used within research and clinical settings. Yet, varying methodologies for cleaning immunoassay data with out of range (OOR) samples may alter characteristic levels of CRP, thereby obscuring interpretation and reliability. This study investigated the influence of eight immunoassay OOR data treatment techniques on salivary CRP (sCRP) samples from at-risk adolescents. Participants from the ‘Sleep and Education: learning New Skills Early’ (SENSE) Study were 86 adolescents at-risk for depression (50 female), aged 14.29 years (SD=1.04). ANOVA results showed no statistically significant differences in average morning (F(7, 590)=1.24, p=.28) and evening (F(7, 599)=1.29, p=.25) values produced by each OOR data cleaning technique. However, varying techniques produced differences in the magnitude of Pearson’s correlations between consecutive saliva samples (r’s between .27 – .78), and influenced the significance of a sCRP diurnal pattern; two techniques produced statistically higher morning than evening sCRP levels (t(85)=2.70, p=.01 and t(85)=2.67, p=.01), whereas six techniques failed to find statistical differences between morning and evening sCRP levels (p’s >.05). Varying techniques also produced statistically divergent associations between sCRP and age and depressive symptoms. Results from this study provide evidence for the temporal stability of sCRP among adolescents, show winsorization as an effective OOR data management technique, and highlight the influence of methodological decisions in cleaning salivary biomarker data and the need for consistency within the field.

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Faculty Opinions recommendation of Is propensity to obesity associated with the diurnal pattern of core body temperature?

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.719282746.793500463 ◽

2014 ◽

Author(s):

David Allison ◽

Julia Gohlke

Keyword(s):

Body Temperature ◽

Core Body Temperature ◽

Diurnal Pattern ◽

Core Body

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Effects of meteorological factors and groundwater depths on plant sap flow velocities in karst critical zone

The Science of The Total Environment ◽

10.1016/j.scitotenv.2021.146764 ◽

2021 ◽

pp. 146764

Author(s):

Yan Deng ◽

Song Wu ◽

Jing Ke ◽

Aijun Zhu

Keyword(s):

Sap Flow ◽

Meteorological Factors ◽

Critical Zone ◽

Plant Sap ◽

Flow Velocities

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Sap flow evidence of chilling injury and recovery in mangroves following a spring cold spell

Trees ◽

10.1007/s00468-021-02089-9 ◽

2021 ◽

Author(s):

Xiaoxuan Gu ◽

Chen Yang ◽

Hewei Zhao ◽

Naxu Hu ◽

Ken W. Krauss ◽

...

Keyword(s):

Sap Flow ◽

Chilling Injury ◽

Cold Spell

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The European Heat Wave 2018: The Dendroecological Response of Oak and Spruce in Western Germany

Forests ◽

10.3390/f12030283 ◽

2021 ◽

Vol 12 (3) ◽

pp. 283

Author(s):

Burkhard Neuwirth ◽

Inken Rabbel ◽

Jörg Bendix ◽

Heye R. Bogena ◽

Boris Thies

Keyword(s):

Heat Wave ◽

Tree Ring ◽

Sap Flow ◽

Hot Spring ◽

Ring Width ◽

Deciduous Tree ◽

Climatic Parameters ◽

Oak Trees ◽

Heat Response ◽

Western Germany

The European heat wave of 2018 was characterized by extraordinarily dry and hot spring and summer conditions in many central and northern European countries. The average temperatures from June to August 2018 were the second highest since 1881. Accordingly, many plants, especially trees, were pushed to their physiological limits. However, while the drought and heat response of field crops and younger trees have been well investigated in laboratory experiments, little is known regarding the drought and heat response of mature forest trees. In this study, we compared the response of a coniferous and a deciduous tree species, located in western and central–western Germany, to the extreme environmental conditions during the European heat wave of 2018. Combining classic dendroecological techniques (tree–ring analysis) with measurements of the intra–annual stem expansion (dendrometers) and tree water uptake (sap flow sensors), we found contrasting responses of spruce and oak trees. While spruce trees developed a narrow tree ring in 2018 combined with decreasing correlations of daily sap flow and dendrometer parameters to the climatic parameters, oak trees developed a ring with above–average tree–ring width combined with increasing correlations between the daily climatic parameters and the parameters derived from sap flow and the dendrometer sensors. In conclusion, spruce trees reacted to the 2018 heat wave with the early completion of their growth activities, whereas oaks appeared to intensify their activities based on the water content in their tree stems.

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