文献类型：期刊文献

英文题名：Developing crown shape model considering a novel competition index-- a case for Korean pine plantation in Northeast China

作者：Sun, Yunxia[1,2] Feng, Jian[3] Chen, Dongsheng[4] Gao, Huilin[2] Zou, Hongtao[1]

第一作者：Sun, Yunxia

通信作者：Zou, HT[1]

机构：[1]Shenyang Agr Univ, Coll Land & Environm, Ctr Postdoctoral Studies Agr Resources & Environm, Shenyang 98428, Liaoning, Peoples R China;[2]Shenyang Agr Univ, Coll Forestry, Shenyang, Liaoning, Peoples R China;[3]Liaoning Acad Forestry Sci, Shenyang, Liaoning, Peoples R China;[4]Chinese Acad Forestry, Res Inst Forestry, State Key Lab Tree Genet & Breeding, Key Lab Tree Breeding & Cultivat,State Forestry &, Beijing 100091, Peoples R China

年份：0

外文期刊名：CANADIAN JOURNAL OF FOREST RESEARCH

收录：;EI(收录号：20223812778025);Scopus(收录号：2-s2.0-85138251978);WOS:【SCI-EXPANDED(收录号:WOS:000917256200001)】；

基金：The authors are grateful to the students who contributed to our field investigation. This study was financed by the startup funds for postdoctoral research from Shenyang Agricultural University (X2021036) .

语种：英文

外文关键词：crown radius; crown length index; modified Kozak equation; crown asymmetry; branch analysis

摘要：Effect of neighbor tree competition on crown shape of Korean pine plantation in Northeast China was studied. A total of 48 trees aged 7-58 years were felled, and all living branches were measured. A novel neighbor competition index that considered the overlap length between subject tree and neighbor tree crowns was created and incorporated into crown shape model. The effects of neighboring competition on crown shape, largest crown radius, and inflection point were analyzed. A dummy variable approach was used to detect crown asymmetry. The crown length index (CLI) of the subject tree was selected as the best neighbor competition index, and the mean square error reduction compared with that of the basic model was 2.0% after incorporating CLI. Crown radius displayed differences in the four cardinal directions and followed the order north > west > south > east. The crown radius in four directions for different ages decreased with increasing CLI and the difference increased with increasing tree age. The competition index, which considers horizontal and vertical competition effects, can significantly improve the performance of crown shape model. Both of inflection point and largest crown radius increased with increasing of CLI; however, the Pearson correlation coefficient was not significant (P > 0.05).