{"title":"西班牙核桃(Juglans x intermedia)Mj209xRa人工林树冠竞争因子的估算","authors":"J. Fernández-Moya, I. Urbán-Martínez","doi":"10.12899/ASR-1931","DOIUrl":null,"url":null,"abstract":"Many walnut ( Juglans spp.) planted forests oriented for timber production have been established during the last decades. These plantations usually have a relatively low initial density (250-400 trees ha -1 ) and 1 or 2 thinnings are needed for valuable timber production (75-150 trees ha -1 for final harvesting). Hence, forest managers need to design when to perform the thinnings and how to do it. Analyzing the trees crown area is a very helpful and easy-to-use tool to evaluate the competence between trees and design the thinnings. The present study proposes two statistical models to estimate Crown Diameter (CD) and Crown Competence Factor (CCF) as a function of Diameter at Breast Height (DBH) for hybrid walnut ( Juglans x intermedia ) Mj209xRa planted forests, within a DBH range between 5 cm (min) and 33 cm (max). CD and DBH were measured in 702 trees at the Bosques Naturales SA walnut planted forests in Cuenca, Girona and A Coruna (Spain). The CCF model is a tool to evaluate the Crown Competition Factor as a function of measured DBH in a plantation, and, accordingly, decide if a thinning should be done or not yet and design it.","PeriodicalId":37733,"journal":{"name":"Annals of Silvicultural Research","volume":"44 1","pages":"24-29"},"PeriodicalIF":0.0000,"publicationDate":"2020-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Estimation of crown competition factor for hybrid walnut (Juglans x intermedia) Mj209xRa planted forests in Spain\",\"authors\":\"J. Fernández-Moya, I. Urbán-Martínez\",\"doi\":\"10.12899/ASR-1931\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Many walnut ( Juglans spp.) planted forests oriented for timber production have been established during the last decades. These plantations usually have a relatively low initial density (250-400 trees ha -1 ) and 1 or 2 thinnings are needed for valuable timber production (75-150 trees ha -1 for final harvesting). Hence, forest managers need to design when to perform the thinnings and how to do it. Analyzing the trees crown area is a very helpful and easy-to-use tool to evaluate the competence between trees and design the thinnings. The present study proposes two statistical models to estimate Crown Diameter (CD) and Crown Competence Factor (CCF) as a function of Diameter at Breast Height (DBH) for hybrid walnut ( Juglans x intermedia ) Mj209xRa planted forests, within a DBH range between 5 cm (min) and 33 cm (max). CD and DBH were measured in 702 trees at the Bosques Naturales SA walnut planted forests in Cuenca, Girona and A Coruna (Spain). The CCF model is a tool to evaluate the Crown Competition Factor as a function of measured DBH in a plantation, and, accordingly, decide if a thinning should be done or not yet and design it.\",\"PeriodicalId\":37733,\"journal\":{\"name\":\"Annals of Silvicultural Research\",\"volume\":\"44 1\",\"pages\":\"24-29\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2020-02-10\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Annals of Silvicultural Research\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.12899/ASR-1931\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Annals of Silvicultural Research","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.12899/ASR-1931","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Estimation of crown competition factor for hybrid walnut (Juglans x intermedia) Mj209xRa planted forests in Spain
Many walnut ( Juglans spp.) planted forests oriented for timber production have been established during the last decades. These plantations usually have a relatively low initial density (250-400 trees ha -1 ) and 1 or 2 thinnings are needed for valuable timber production (75-150 trees ha -1 for final harvesting). Hence, forest managers need to design when to perform the thinnings and how to do it. Analyzing the trees crown area is a very helpful and easy-to-use tool to evaluate the competence between trees and design the thinnings. The present study proposes two statistical models to estimate Crown Diameter (CD) and Crown Competence Factor (CCF) as a function of Diameter at Breast Height (DBH) for hybrid walnut ( Juglans x intermedia ) Mj209xRa planted forests, within a DBH range between 5 cm (min) and 33 cm (max). CD and DBH were measured in 702 trees at the Bosques Naturales SA walnut planted forests in Cuenca, Girona and A Coruna (Spain). The CCF model is a tool to evaluate the Crown Competition Factor as a function of measured DBH in a plantation, and, accordingly, decide if a thinning should be done or not yet and design it.