Mechanisms of local regeneration community assembly under broad-leaved Korean pine forests


Abstract

Aims. To determine the aggregation scales/sizes and elucidate the assembly mechanisms of local seedling and sapling communities in broad-leaved Korean pine forests.

Methods . Based on regeneration survey data from four broad-leaved Korean pine forest plots, Ripley's g(r) was fitted using a Thomas process with a two-nested-scale function. Hierarchical clustering was used to delineate local communities, followed by calculating the abundance-based and presence-based standardized effect size of mean pairwise leaf trait distances (SES.MPD) and the standardized effect size of species evenness (SES.E). The overall community characteristics were determined by evaluating the degree of distribution tendency (D) values of the three indicators above. Redundancy analysis (RDA) was performed to assess the relationship between local canopy environmental variables and community-weighted mean (CWM) traits.

Results. The small aggregation scale for local seedling and sapling communities was approximately 1 m, while the large scale was approximately 15 m. At the large scale, the seedling communities had 42.623 small patches (1.732 seedlings/patch) on average, and the sapling communities had an average of 20.329 patches (1.149 saplings/patch). Across the 1–15 m scales, both abundance-weighted SES.MPD and SES.E for the seedling and sapling communities were significantly greater than zero. The presence-based SES.MPD was significantly greater than zero across all scales for saplings but was only significant at smaller scales for seedlings. The values of D for the three indicators were slightly greater than one across all spatial scales. The seedling communities exhibited higher D values for abundance-weighted SES.MPD and SES.E than the sapling communities. Additionally, the seedling communities exhibited higher D values for presence-based SES.MPD at smaller aggregation scales, although this trend was reversed at larger scales. The RDA showed that total R2 (0.021–0.245) increased with the spatial scale and was consistently higher in the sapling communities than in the seedling communities. Compared with the seedling communities, the sapling communities demonstrated weaker or even opposite correlations in CWM.LA, SLA, and LW with vertical distribution tendency degrees and local coniferous LAI.

Conclusions. The assembly of local regeneration communities was dominated by stochastic processes. Among deterministic processes, limited dispersal leads to spatial and trait aggregation of regeneration communities across all spatial scales; canopy-driven environmental filtering accumulates with regeneration development, and limiting similarity has a more important role in local sapling communities than in seedling communities at smaller spatial scales. Differences in ontogenetic strategy lead to variation in trait – canopy relationships between local seedling and sapling communities.

Ask to review this manuscript

Notes for potential reviewers

  • Volunteering is not a guarantee that you will be asked to review. There are many reasons: reviewers must be qualified, there should be no conflicts of interest, a minimum of two reviewers have already accepted an invitation, etc.
  • This is NOT OPEN peer review. The review is single-blind, and all recommendations are sent privately to the Academic Editor handling the manuscript. All reviews are published and reviewers can choose to sign their reviews.
  • What happens after volunteering? It may be a few days before you receive an invitation to review with further instructions. You will need to accept the invitation to then become an official referee for the manuscript. If you do not receive an invitation it is for one of many possible reasons as noted above.

  • PeerJ does not judge submissions based on subjective measures such as novelty, impact or degree of advance. Effectively, reviewers are asked to comment on whether or not the submission is scientifically and technically sound and therefore deserves to join the scientific literature. Our Peer Review criteria can be found on the "Editorial Criteria" page - reviewers are specifically asked to comment on 3 broad areas: "Basic Reporting", "Experimental Design" and "Validity of the Findings".
  • Reviewers are expected to comment in a timely, professional, and constructive manner.
  • Until the article is published, reviewers must regard all information relating to the submission as strictly confidential.
  • When submitting a review, reviewers are given the option to "sign" their review (i.e. to associate their name with their comments). Otherwise, all review comments remain anonymous.
  • All reviews of published articles are published. This includes manuscript files, peer review comments, author rebuttals and revised materials.
  • Each time a decision is made by the Academic Editor, each reviewer will receive a copy of the Decision Letter (which will include the comments of all reviewers).

If you have any questions about submitting your review, please email us at [email protected].