Pattern reveals process: spatial organisation of a Kamchatkan stone birch forest

摘要

Background: Spatial patterns within forests reflect their formative processes. In Kamchatka, the dominant stone birch (Betula ermanii) forest exists in a primeval state. Betula species can reproduce via clonally produced ramets, leading to a clustered distribution of stems, or from seed on open ground, although subsequent mortality may obscure initial establishment patterns. Methods: Spatial patterns of all trees and regenerating stems in a fully mapped 0.25 ha plot were analysed using the g(r) function and the pattern of trees modelled using a Matérn cluster process. Mark correlation analysis was used to detect patterns in stem sizes. Results: Clustering of trees at scales up to 3 m occurred, with model parameters indicating a density of 180 clusters ha−1, each containing on average three stems 1 cm diameter at breast height (DBH) within a 1.6 m radius. Stem size compensation was detected, with nearby trees smaller than expected by chance. Regenerating stems were strongly clustered at scales below 3.5 m and from 5-8 m, and were aggregated around small trees (10 cm DBH) but not large trees (≥10 cm DBH), or in gaps. Conclusions: These patterns are consistent with clonal reproduction followed by competition as the processes determining spatial structure in old-growth stone birch forests.View full textDownload full textKeywords Betula ermanii , boreal forest, Far Eastern Russia, Kamchatka, mark correlation, Matérn cluster process, pair correlation function, spatial point pattern analysisRelated var addthis_config = { ui_cobrand: "Taylor & Francis Online", services_compact: "citeulike,netvibes,twitter,technorati,delicious,linkedin,facebook,stumbleupon,digg,google,more", pubid: "ra-4dff56cd6bb1830b" }; Add to shortlist Link Permalink http://dx.doi.org/10.1080/17550874.2010.528804