Growth space competition index(GSCI)and application in the individual intraspecies competition of Pinus tabulaeformis and Platycladus orientalis forests
MA Lu-yi, WANG Xi-qun
The Key Laboratory for Silviculture and Conservation of Ministry of Education, Beijing Forestry University, Beijing 100083
Competition between individuals is the foundation of the forest ecosystem research.Basically,there are two research methods,qualitative description and quantitative analysis.Over 20 various competition indices were developed to estimate competition degree.However,none of these indices could accommodate the problem of tree canopy changes in the quantitative analysis reasonably.This paper put forward a new conception of Growth Space Competition Index(GSCI) first time.GSCI is the ratio of canopy surface area to basal-area of trunk.The canopy surface area received most of the light and is an important index that determines the productivity efficiency.Thus,using canopy surface area as a competition parameter in population and community is the best way to accommodate the problem of canopy changes in the quantitative analysis.GSCI is an no-dimension measure unit on canopy cover degree.This paper also applied the GSCI in the intraspecies individual competition of Pinus tabulaeformis and Platycladus orientalis forests,and compared with Competition Index(CI) and Growth Space Index(GSI).
马履一, 王希群. 生长空间竞争指数及其在油松、侧柏种内竞争中的应用研究[J]. , 2006, 25(5): 385-389.
MA Lu-yi, WANG Xi-qun. Growth space competition index(GSCI)and application in the individual intraspecies competition of Pinus tabulaeformis and Platycladus orientalis forests. , 2006, 25(5): 385-389.
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