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Natural regeneration dynamics of thr

時(shí)間:2023-04-26 18:23:35 工業(yè)農(nóng)業(yè)論文 我要投稿
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Natural regeneration dynamics of three dry deciduous forest species in Chacocente Wildlife Reserve, Nicaragua

A study was conducted to examine the natural regeneration of three dry forest species, Lysiloma divaricatum (Jacq.), Tabebuia ochracea (Cham.) and Lonchocarpus minimiflorus (Donn. Sm.) over a three-year period and to analyze heterogeneity of regeneration in relationship to topographic slope and incidence of light in Chacocente Wildlife Reserve in Nicaragua. Permanent sample plots were established in 2001, and all individuals with height as low as 10 cm and diameter as large as 10 cm were recorded for three consecutive years from 2001 to 2003. The results show that the density of naturally regenerated individuals varied significantly among species, as well as over time. L. minimiflorus and T. ochracea had higher densities compared with L. divaricatum, and the net change in population density was slightly positive for T. ochracea only. Regeneration was more abundant in the gentle and steep slopes under partial exposure of the crown to sunlight, thus resulting in aggregated pattern of distribution, especially for L. minimiflorus and T. ochracea. We concluded that natural regeneration alone is not sufficient to maintain the desired number of stocks of these species, and an immediate restoration measure should be taken to assist the natural regeneration process.

作 者: Guillermo Castro Marín Mulualem Tigabu Benigno González Rivas Per Christer Odén   作者單位: Guillermo Castro Marín,Benigno González Rivas(Facultad de Recursos Naturales y del Ambiente, Universidad Nacional Agraria, Apartado posta 453, Managua, Nicaragua)

Mulualem Tigabu,Per Christer Odén(Swedish University of Agricultural Sciences, Faculty of Forest Sciences, Department of Forest Genetics and Plant Physiology, Tropical Silviculture and Seed Laboratory, SE-901 83, Umea, Sweden) 

刊 名: 林業(yè)研究(英文版)  英文刊名: JOURNAL OF FORESTRY RESEARCH  年,卷(期): 2009 20(1)  分類號(hào): S7  關(guān)鍵詞: Central America   mortality   regeneration niche   spatial pattern   dry forest