Paper · 2022 · Journal of Forestry Research

Model development to estimate site index values for six major tree species in North Korea

Sohee Park; A-Ram Yang; Eun-hee Kim; et al.

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verbatim quotes
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citations
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research areas
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Open access · cc-by

Abstract

Abstract Due to considerable deforestation in North Korea, there is a need to plan forest restoration programs based on scientific forest management. In this study, a methodology was developed for estimating the site index values of six major tree species and the forest productivity potential. The site index values of these tree species were derived in South Korea using the Chapman-Richards equation. These values were used with data from the 6th National Forest Inventory, which included 20 types of edaphic, topographic, and climatic factors, and random forest analysis—a widely used machine learning technique for spatial prediction—to develop a new model for estimating the site index values of these species across South Korea. The prediction accuracy of this model was evaluated using the root mean square error. The results show that the prediction accuracy was high, with a root mean square error of ~ 1 m. Moreover, the importance of the variables related to climate and geography was generally high. The proposed site index estimation model for six tree species was applied across North Korea, and its effectiveness tested by comparing the estimated values with those reported in literature from North Korea. The differences between the model outputs and recorded data in the northern alpine regions were presumably due to the lack of data for high-altitude regions in South Korea. This model is based on the determination of the suitability of tree species in restoration efforts. Therefore, it can contribute to the evaluation of forest productivity in North Korea and may help plan efficient forest restoration programs.

Abstract from the paper’s OpenAlex record; open copy licensed cc-by. Read at the source ↗

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Claims 4

Method / resourceobservedoriginal resultpositivemeasured

Claim · model-written summary

The site index model had high prediction accuracy, with a root mean square error of about 1 m.

Taxon
six major tree speciest0
Outcome
prediction accuracye0
Value
~ 1 me0
Setting
North Koreat0

Verbatim

t0

“Model development to estimate site index values for six major tree species in North Korea”

✓ located verbatim in the source · title, characters 0–89 · show in text ↑
e0

“The results show that the prediction accuracy was high, with a root mean square error of ~ 1 m”

✓ located verbatim in the source · abstract, characters 822–916 · show in text ↑
Observationobservedoriginal resultmeasured

Claim · model-written summary

Climate and geography variables were generally of high importance in the site index model.

Taxon
six major tree speciest0
Outcome
importance of the variables related to climate and geographye1
Direction
highe1
Setting
North Koreat0

Verbatim

t0

“Model development to estimate site index values for six major tree species in North Korea”

✓ located verbatim in the source · title, characters 0–89 · show in text ↑
e1

“Moreover, the importance of the variables related to climate and geography was generally high”

✓ located verbatim in the source · abstract, characters 918–1011 · show in text ↑
Method / resourceauthor interpretationoriginal resultnegativemeasured

Claim · model-written summary

Model outputs differed from recorded data in northern alpine regions, presumably because of lack of high-altitude data from South Korea.

Taxon
six major tree speciest0
Outcome
differences between the model outputs and recorded datae2
Qualifier
presumably due to the lack of data for high-altitude regions in South Koreae2
Comparator
recorded datae2
Setting
northern alpine regionse2

Verbatim

t0

“Model development to estimate site index values for six major tree species in North Korea”

✓ located verbatim in the source · title, characters 0–89 · show in text ↑
e2

“The differences between the model outputs and recorded data in the northern alpine regions were presumably due to the lack of data for high-altitude regions in South Korea”

✓ located verbatim in the source · abstract, characters 1222–1393 · show in text ↑
Recommendationauthor interpretationoriginal resultpositivebasis n/a

Claim · model-written summary

The model may help evaluate forest productivity in North Korea and plan forest restoration programs.

Taxon
six major tree speciest0
Outcome
evaluation of forest productivity in North Koreae3
Qualifier
may help plan efficient forest restoration programse3
Setting
North Koreae3

Verbatim

t0

“Model development to estimate site index values for six major tree species in North Korea”

✓ located verbatim in the source · title, characters 0–89 · show in text ↑
e3

“Therefore, it can contribute to the evaluation of forest productivity in North Korea and may help plan efficient forest restoration programs”

✓ located verbatim in the source · abstract, characters 1495–1635 · show in text ↑