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Diversity and structural composition of species in dipterocarp forests:a study from Fasiakhali Wildlife Sanctuary, Bangladesh 被引量:4
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作者 s.c.das M.S.Alam M.A.Hossain 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第5期1241-1249,共9页
Fasiakhali Wildlife Sanctuary is a protected area composed of tropical remnant rainforest that harbor substantial number of large,old Garjan(Dipterocarpus spp.)trees.The present study assessed composition,structure ... Fasiakhali Wildlife Sanctuary is a protected area composed of tropical remnant rainforest that harbor substantial number of large,old Garjan(Dipterocarpus spp.)trees.The present study assessed composition,structure and diversity of the species in this protected area.A total of 32 trees species were recorded with DBH ≥ 11 cm belonging to 24 genera and 19 families.The forest is low in plant diversity as represented by Shannon–Wiener diversity and Simpson Dominance indices.Dipterocarpus turbinatus was the most dominant species with maximum relative density,frequency,dominance,and importance value index.Syzygium firmum and Tectona grandis followed in terms of dominance.The structural composition indicated higher number of individuals in the medium growth classes(41 to 〈 511 cm DBH and 16–20 m height ranges),whereas D.turbinatus was the only species that dominated most of the growth classes.Poor stem density in lower growth classes indicated meager recruitment of regeneration which may be due to lower annual precipitation,increased grazing and encroachments.This study will help to understand the patterns of tree species composition and diversity in the remnant dipterocarp forests of Bangladesh.It will also contribute to identifying threatened plants to undertake D.turbinatus based conservation and sustainable management of the Fasiakhali Wildlife Sanctuary. 展开更多
关键词 Species diversity Structural composition Protected area Importance value index Cluster analysis
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从含有机添加剂的氯化铅电解液中电积铅
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作者 s.c.das 李义根 《有色矿冶》 北大核心 1990年第2期32-37,共6页
对含添加剂的氯化铅电解液进行了电积铅的研究。添加剂分别为松香,镁絮凝剂,明胶,骨胶,β—荼酚以及骨胶加β—荼酚。初步研究表明,同时含骨胶及β—荼酚添加剂的氯化物电解液,可产出较致密的铅沉积物,且电流效率较高。研究了铅、骨胶... 对含添加剂的氯化铅电解液进行了电积铅的研究。添加剂分别为松香,镁絮凝剂,明胶,骨胶,β—荼酚以及骨胶加β—荼酚。初步研究表明,同时含骨胶及β—荼酚添加剂的氯化物电解液,可产出较致密的铅沉积物,且电流效率较高。研究了铅、骨胶与β—荼酚的浓度、溶液pH值,温度、电流密度等参数对电流效率,沉积物特性及阴极电位的影响。结果表明,当电解液含铅30g/l,骨胶2g/l β—荼酚0.1g/l,pH0.75~0.95,温度70℃及电流密度50A/m^2时,可获得致密铅,其电流效率约90%。搅拌电解液可提高电流效率约5%,并使沉积物特性得到改善。 展开更多
关键词 电积 电解液 氯化铅
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茶树组织培养:植株再生和在苗圃中的移植生长
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作者 s.c.das T.T.Barman R.Singh 《茶叶科学技术》 1990年第4期41-41,43,共2页
在含0.5mg/1IBA的滤纸桥系统和液体振荡培养及在土壤:泥炭(1:1)混合物中,获得了根的产生.虽然用液体振荡培养方法其根的发生较快,但这些植株移植在土壤中的生长较差;在土壤和泥炭混合物中直接生根虽然较慢,但将植株定植在大气环境的土... 在含0.5mg/1IBA的滤纸桥系统和液体振荡培养及在土壤:泥炭(1:1)混合物中,获得了根的产生.虽然用液体振荡培养方法其根的发生较快,但这些植株移植在土壤中的生长较差;在土壤和泥炭混合物中直接生根虽然较慢,但将植株定植在大气环境的土壤中生长较好.将植株用低温、漫射光和高湿度预处理,能使植株更加强壮,且提高了植株在苗圃中的移植成功率.本研究的目的在于:a)发展一种再生苗有效生根的技术;b)使生根苗成功地移植于土壤的技术标准化;c)使植株适应大田环境. 展开更多
关键词 组织培养 液体振荡 再生苗 生根苗 漫射光 大气环境 愈伤组织 技术标准化 塑料钵 培苗
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