Paper · 2025 · Biotropica

Leaf‐Litter Depth, Not Canopy Openness, Mediates the Occurrence of an Invasive Shrub From the Forest Edge to Interior

Hao Ran Lai; Kwek Yan Chong; Melissa Qi Yun Wong; et al.

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claims
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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-nc

Abstract

ABSTRACT Continental tropical forests with intact canopies and densely shaded understories are often perceived to be particularly resistant to biological invasions, yet canopy disturbances leave them vulnerable to gap colonization by invasive plants. The Neotropical shrub, Miconia crenata , is an example of a successful invader in intact continental tropical forests but is generally well known to be restricted to forest trails and edges. However, existing studies that quantify the decline in M. crenata from forest edge to interior rarely compare the relative importance of direct edge effects with indirect edge effects mediated by processes that vary with distance from forest edge. To address this gap, we aim here to identify the most relevant processes influencing M. crenata invasion in the secondary tropical forests of Singapore. Using a path model on field observations collected using an adaptive cluster sampling methodology, we found that the occurrence of M. crenata did not change directly with distance from forest edge. Instead, the decreased occurrence of M. crenata in forest interiors was indirectly mediated by thicker leaf litter, which is detrimental to the small seeds of M. crenata . While there was a direct positive relationship between canopy openness and M. crenata occurrence, canopy openness was not a mediator for relationships with distance to forest edge. These findings suggest that environmental filtering of germinants is an important determinant of the invasion success of M. crenata , and that litter retention could be an effective management against M. crenata even in smaller fragments where canopy gaps have extended far into the forest interior.

Abstract from the paper’s OpenAlex record; open copy licensed cc-by-nc. 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 5

Associationobservedoriginal resultno effectmeasured

Claim · model-written summary

Occurrence did not change directly with forest edge distance.

Taxon
M. crenataMiconia crenatae0
Outcome
occurrencee0
Direction
did not changee0
Setting
forest edgee0

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Miconia crenata
Miconia crenata · TaxonDamien Wallace · CC BY 4.0 · Wikimedia Commons ↗

Verbatim

e0

“the occurrence of M. crenata did not change directly with distance from forest edge”

✓ located verbatim in the source · abstract, characters 956–1039 · show in text ↑
Associationobservedoriginal resultnegativemeasured

Claim · model-written summary

Thicker leaf litter indirectly mediated decreased occurrence in forest interiors.

Taxon
M. crenataMiconia crenatae0
Outcome
occurrencee0
Direction
decreasede0
Qualifier
thicker leaf littere0
Setting
forest interiorse0

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Miconia crenata
Miconia crenata · TaxonDamien Wallace · CC BY 4.0 · Wikimedia Commons ↗

Verbatim

e0

“the decreased occurrence of M. crenata in forest interiors was indirectly mediated by thicker leaf litter”

✓ located verbatim in the source · abstract, characters 1050–1155 · show in text ↑
Associationobservedoriginal resultmeasured

Claim · model-written summary

Canopy openness had a direct positive relationship with occurrence.

Taxon
M. crenataMiconia crenatae0
Outcome
occurrencee0
Direction
positivee0
Setting
canopy opennesse0

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Miconia crenata
Miconia crenata · TaxonDamien Wallace · CC BY 4.0 · Wikimedia Commons ↗

Verbatim

e0

“there was a direct positive relationship between canopy openness and M. crenata occurrence”

✓ located verbatim in the source · abstract, characters 1219–1309 · show in text ↑
Associationobservedoriginal resultno effectmeasured

Claim · model-written summary

Canopy openness did not mediate the relationship between edge distance and occurrence.

Taxon
M. crenataMiconia crenatae1
Outcome
relationships with distance to forest edgee0
Direction
not a mediatore0
Setting
canopy opennesse0

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Miconia crenata
Miconia crenata · TaxonDamien Wallace · CC BY 4.0 · Wikimedia Commons ↗

Verbatim

e0

“canopy openness was not a mediator for relationships with distance to forest edge”

✓ located verbatim in the source · abstract, characters 1311–1392 · show in text ↑
e1

“M. crenata occurrence”

✓ located verbatim in the source · abstract, characters 1288–1309 · show in text ↑
Recommendationauthor interpretationoriginal resultpositivebasis n/a

Claim · model-written summary

Litter retention could be effective management against the invasive shrub.

Taxon
M. crenataMiconia crenatae0
Outcome
litter retentione0

Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Miconia crenata
Miconia crenata · TaxonDamien Wallace · CC BY 4.0 · Wikimedia Commons ↗

Verbatim

e0

“litter retention could be an effective management against M. crenata even in smaller fragments where canopy gaps have extended far into the forest interior”

✓ located verbatim in the source · abstract, characters 1537–1692 · show in text ↑