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Species diversity, regeneration and dominance as influenced by canopy gaps and their characteristics in tropical evergreen forests of Western Ghats, India 被引量:10
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作者 Guddappa Mahalingappa Devagiri Anil Kumar Khaple +4 位作者 Siddagangaiah Mohan Puttanaik Venkateshamurthy Sanjay Tomar Arkalgud Nagaraja Arunkumar Geeta Joshi 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第4期799-810,共12页
Canopy gaps play a significant role in maintaining structure and composition of tropical forests. This study was carried out in tropical evergreen forests of central Western Ghats in India to understand the influence ... Canopy gaps play a significant role in maintaining structure and composition of tropical forests. This study was carried out in tropical evergreen forests of central Western Ghats in India to understand the influence of canopy gap size and the relationship of gap regime attributes to diversity measures and regeneration. The average gap size in the study area was found to be 396 m2 and around half of gaps were 4–8 years old. Gaps created by natural single tree fall were smaller in size but significantly higher in number. Diversity and regeneration of woody species were compared with canopy gaps and intact vegetation. Species richness and diversity was higher in gaps than in intact vegetation. Macaranga peltata, a shade intolerant species dominated gaps while intact vegetation was dominated by shade tolerant Kingiodendron pinnatum.Gap size significantly influenced species diversity and regeneration. Gap area and age were significantly and negatively correlated with diversity measures but positively correlated with regeneration. Among all the attributes of gaps, regeneration was significantly positively correlated with light intensity. Gaps maintained species diversity and favored regeneration of woody species. In addition to gap size and age, other gap ecological attributes also affected species diversity and regeneration. 展开更多
关键词 canopy forests regeneration dominance tropical woody vegetation intact Species dominated
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REGIONAL GEOCHEMISTRY OF RUBBER PLANTATION IN HAINAN ISLAND,CHINA
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作者 Wang Jinghua 《Journal of Geographical Sciences》 SCIE CSCD 1990年第2期79-87,共9页
Hainan Island is located in the northern periphery of the tropical world.The environment is suitable for a number of tropical economic crops.The content of soil organic matter under rubber plantation is around 10- 20 ... Hainan Island is located in the northern periphery of the tropical world.The environment is suitable for a number of tropical economic crops.The content of soil organic matter under rubber plantation is around 10- 20 g kg-1.Cu,Zn,Mn,As,Mg,Ca and K in the soil profile reflect the parent material and the intensive weathering and leaching in the area.Copper has noticeably accumulated in the lower horizon,whereas the concentrations of Ca,Mg and K.in rubber trees are 0.5- 4.9,2.2- 4.3 and 4.6-10.2 g kg-1respectively.These three elements are mostly distributed in the plant roots and are particularly required during the development of new leaves early in the season. 展开更多
关键词 rubber plantation nutrient element tropical soil tropical vegetation
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Insecticidal efficacy of three vegetable oils as post-harvest grain protectants of stored wheat against Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae) 被引量:1
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作者 AMIN NIKPAY 《Insect Science》 SCIE CAS CSCD 2007年第2期145-150,共6页
The lesser grain borer, Rhyzopertha dominica is a major insect pests of stored grain in the tropics. Vegetable oils (chamomile, sweet almond and coconut) at 2.5, 3.5, 5.0, 7.0 and 10.0 mL/kg were tested against Rhyz... The lesser grain borer, Rhyzopertha dominica is a major insect pests of stored grain in the tropics. Vegetable oils (chamomile, sweet almond and coconut) at 2.5, 3.5, 5.0, 7.0 and 10.0 mL/kg were tested against Rhyzopertha dominica (F.) in wheat grain. All bioassays were conductr, d at 30℃ and 65% + 2% RH. Treatments with vegetable oils at high dose (10.0 mL/kg) achieved over 95% control within 24 h of exposure to freshly treated grain, There was little difference between the three oils in their effect. Persistence of oils in grains was tested at short-term storage intervals (48, 72 and 96 h) and intermediate-term intervals (10, 20 and 30 days) after treatments. The activity of all products decreased with storage period. Seed viability was reduced by the high dose rate (10.0 mL/kg) of oil treatments. The potential use of vegetable oils as supplementary or alternative grain protectants against insect damage in traditional grain storage in developing countries is discussed. 展开更多
关键词 Rhyzopertha dominica seed viability traditional grain storage tropics vegetable oils
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