Abstract
Based on the 3-year successive automatic measurement of photosynthetic active radiation above and under the crown of Korean pine and broadleaved mixed forest in Changbai Mountains, as well as the seasonal observation on leaf area index, a semi-empirical model was established to estimate the crown leaf area index of the forest. The results showed that this model could well reflect the seasonal variation of crown leaf area. From the comparison of 3-year leaf area index series, it was found that the date when the leaf area index began to rise was postponed if the date when its air temperature stably surpassed 0 degrees C came late. The dynamics of the leaf area index in whole growth season could be divided into three stages, i. e., rising, relatively stable, and dropping, and at each stage, there was a greater correlation between the leaf area index and the accumulated temperature above 0 degrees C, which could be expressed by Logistic curve and linear equation. The problems existing in the observation and estimation of forest crown leaf area index were discussed.
Abstract from the paper’s OpenAlex record, shown for indexing and research. Copyright remains with the authors or the publisher. Read at the source ↗
The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.
Claims 4
Claim · model-written summary
The semi-empirical model reflected the seasonal variation of crown leaf area of the Korean pine mixed forest.
- Taxon
- Korean pine
Pinus koraiensist0 - Outcome
- seasonal variation of crown leaf areae0
- Comparator
- seasonal observation on leaf area indexe1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Korean pine”
e0“The results showed that this model could well reflect the seasonal variation of crown leaf area”
e1“as well as the seasonal observation on leaf area index, a semi-empirical model was established”
Claim · model-written summary
Leaf area index began to rise later when air temperature stably exceeded 0 degrees C later.
- Taxon
- Korean pinePinus koraiensist0
- Treatment
- the date when its air temperature stably surpassed 0 degrees C came latee0
- Outcome
- the date when the leaf area index began to risee0
- Direction
- postponede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Korean pine”
e0“the date when the leaf area index began to rise was postponed if the date when its air temperature stably surpassed 0 degrees C came late”
Claim · model-written summary
The leaf area index dynamics over the growth season divided into three stages: rising, relatively stable and dropping.
- Taxon
- Korean pinePinus koraiensist0
- Outcome
- The dynamics of the leaf area index in whole growth seasone0
- Qualifier
- could be divided into three stagese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Korean pine”
e0“The dynamics of the leaf area index in whole growth season could be divided into three stages, i. e., rising, relatively stable, and dropping”
Claim · model-written summary
At each stage, leaf area index correlated more strongly with accumulated temperature above 0 degrees C.
- Taxon
- Korean pinePinus koraiensist0
- Treatment
- accumulated temperature above 0 degrees Ce0
- Outcome
- correlation between the leaf area index and the accumulated temperature above 0 degrees Ce0
- Direction
- greatere0
- Qualifier
- at each stagee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Korean pine”
e0“at each stage, there was a greater correlation between the leaf area index and the accumulated temperature above 0 degrees C”