Wiegand, Kerstin

[["dc.bibliographiccitation.firstpage","318"],["dc.bibliographiccitation.issue","2"],["dc.bibliographiccitation.journal","Journal of Vegetation Science"],["dc.bibliographiccitation.lastpage","327"],["dc.bibliographiccitation.volume","27"],["dc.contributor.author","Nguyen, Hong Hai"],["dc.contributor.author","Uria-Diez, Jaime"],["dc.contributor.author","Wiegand, Kerstin"],["dc.date.accessioned","2017-09-07T11:44:38Z"],["dc.date.available","2017-09-07T11:44:38Z"],["dc.date.issued","2015"],["dc.description.abstract","Questions What are the prevailing types of intraspecific spatial distributions and interspecific association patterns at species and life stage levels of trees in a tropical rain forest? Which ecological processes could structure these patterns? Possible processes include dispersal limitation, self‐thinning, facilitation and competition between species and life stages. Location A tropical broad‐leaved forest in north‐central Vietnam. Methods We used univariate and bivariate pair‐correlation functions to investigate the spatial distribution and association patterns of 18 abundant tree species. To disentangle first‐ and second‐order effects, we used a scale separation approach with the heterogeneous Poisson process as null model. Results (1) Sixteen of 18 species had aggregated patterns at various scales and regardless of their abundance. (2) Significant and aggregated patterns were found in 64% of all specific life stages. (3) At scales up to 15 m, 12.4% species pairs showed significant associations, among that 71% were spatial attractions, 5% were spatial repulsions and 24% were non‐essential interactions. (4) In different life stage associations, attractions (81%) predominated over repulsions (19%) at small scales of up to 15 m. Conclusions Our findings provide evidence that dispersal limitation may regulate the spatial patterns of tree species. Moreover, positive spatial associations between tree species and life stages suggest the presence of species herd protection and/or facilitation in this forest stand, while the persistence of intraspecific aggregation through life stages suggests a very late onset or even absence of self‐thinning. Habitat heterogeneity plays an important role for species distribution patterns, and the spatial segregation occurs at a scale around 15 m in this forest."],["dc.identifier.doi","10.1111/jvs.12361"],["dc.identifier.gro","3148941"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/5583"],["dc.language.iso","en"],["dc.notes.intern","Wiegand Crossref Import"],["dc.notes.status","public"],["dc.notes.submitter","chake"],["dc.relation.issn","1100-9233"],["dc.relation.orgunit","Abteilung Ökosystemmodellierung"],["dc.subject.gro","Dispersal limitation"],["dc.subject.gro","Neutral theory"],["dc.subject.gro","Pair-correlation function"],["dc.subject.gro","Point pattern analysis"],["dc.subject.gro","Self-thinning"],["dc.subject.gro","Spatial pattern"],["dc.subject.gro","Species association"],["dc.subject.gro","Species herd protection"],["dc.subject.gro","Tropical evergreen forest"],["dc.subject.gro","Vietnam"],["dc.title","Spatial distribution and association patterns in a tropical evergreen broad-leaved forest of north-central Vietnam"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","no"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","309"],["dc.bibliographiccitation.issue","3"],["dc.bibliographiccitation.journal","Journal of Tropical Forest Science"],["dc.bibliographiccitation.lastpage","319"],["dc.bibliographiccitation.volume","26"],["dc.contributor.author","Nguyen, Hong Hai"],["dc.contributor.author","Wiegand, Kerstin"],["dc.contributor.author","Getzin, Stephan"],["dc.date.accessioned","2017-09-07T11:50:52Z"],["dc.date.available","2017-09-07T11:50:52Z"],["dc.date.issued","2014"],["dc.description.abstract","Streblus macrophyllus is a shade-tolerant and subcanopy tree species common to tropical evergreen forests in northern Vietnam. However, its ecology is poorly known. We used spatial point pattern analysis to describe the spatial arrangement of tree individuals within a forest community dominated by S. macrophyllus. All individual trees with diameter at breast height larger than 2.5 cm in a 1-ha plot were mapped and measured. The overall pattern of this species was a regular distribution at scales up to 2 m. Its juveniles and subadults were strongly aggregated, but adult trees were regular at scales of up to 3 m, implying evidence of density dependent thinning. The spatial pattern of S. macrophyllus strongly affected the patterning of the whole plot. In S. macrophyllus, juveniles and subadults were similarly distributed relative to adults and showed additional clumping independent of the adults. The overall interspecific association between adults of other species and S. macrophyllus at different life-history stages also showed independence. We conclude that S. macrophyllus is a predominant competitor within the community and it follows a gap-phase regeneration mode."],["dc.identifier.gro","3147838"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/5164"],["dc.language.iso","en"],["dc.notes.status","final"],["dc.notes.submitter","chake"],["dc.relation.orgunit","Abteilung Ökosystemmodellierung"],["dc.subject","Point pattern analysis forest community gap-phase regeneration mode intra- and interspecific associations"],["dc.subject.gro","Forest community"],["dc.subject.gro","Gap-phase regeneration mode"],["dc.subject.gro","Intra- and interspecific associations"],["dc.subject.gro","Point pattern analysis"],["dc.title","Spatial patterns and demographics of Streblus macrophyllus trees in a tropical evergreen forest, Vietnam."],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","no"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","257"],["dc.bibliographiccitation.issue","2"],["dc.bibliographiccitation.journal","Journal of Forestry Research"],["dc.bibliographiccitation.lastpage","268"],["dc.bibliographiccitation.volume","25"],["dc.contributor.author","Nguyen, Hong Hai"],["dc.contributor.author","Wiegand, Kerstin"],["dc.contributor.author","Getzin, Stephan"],["dc.date.accessioned","2017-09-07T11:52:28Z"],["dc.date.available","2017-09-07T11:52:28Z"],["dc.date.issued","2014"],["dc.description.abstract","Ecological interactions of species and thus their spatial patterns may differ between homogeneous and heterogeneous forests. To account for this, techniques of point pattern analysis were implemented on mapped locations of tree individuals from two 1-ha tropicalforest plots in Vietnam. We analyzed the effect of environmental heterogeneity on tree distributions; spatial distribution patterns of dominant species; inter-specific associations; and conspecific associations between life stages. Our analyses showed that: environmental conditions were homogeneous at plot 1 but heterogeneous at plot 2; in both plots, all six dominant species were aggregated at various scales up to 30 m, and tree species were aggregated at larger scales in the homogeneous site than in the heterogeneous site; attraction between pairs of species was remarkably higher at the homogeneous site while negative associations were more frequent in the heterogeneous site; some species, H. kurzii, T. ilicifolia (homogeneous plot) and D. sylvatica, S. wightianum (heterogeneous plot), showed a lack of early life-stage individuals near conspecific adults. Moreover, additional clustering of young individuals was independent from conspecific adults, except D. sylvatica in both sites. These findings are consistent with the Janzen-Connell hypothesis. Overall, habitat heterogeneity influences spatial patterns and inter-specific associations of the tree species and evidences of self-thinning are shown in most species."],["dc.identifier.doi","10.1007/s11676-014-0457-y"],["dc.identifier.gro","3148925"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/5564"],["dc.language.iso","en"],["dc.notes.intern","Wiegand Crossref Import"],["dc.notes.status","public"],["dc.notes.submitter","chake"],["dc.relation.issn","1007-662X"],["dc.relation.orgunit","Abteilung Ökosystemmodellierung"],["dc.subject.gro","environmental heterogeneity"],["dc.subject.gro","northern Vietnam"],["dc.subject.gro","spatial point pattern analysis"],["dc.subject.gro","tropical evergreen forest"],["dc.title","Spatial distributions of tropical tree species in northern Vietnam under environmentally variable site conditions"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","no"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]