Proyecto de demostración de reforestación en minas de estaño abandonadas y desarboladas en Malays... more Proyecto de demostración de reforestación en minas de estaño abandonadas y desarboladas en Malaysia peninsular
The potential of kenaf (Hibiscus cannabinus L.) for phytoremediation of lead (Pb) on sand tailing... more The potential of kenaf (Hibiscus cannabinus L.) for phytoremediation of lead (Pb) on sand tailings was investigated. A pot experiment employing factorial design with two main effects of fertilizer and lead was conducted in a nursery using sand tailings from an ex-tin mine as the growing medium. Results showed that Pb was found in the root, stem, and seed capsule of kenaf but not in the leaf. Application of organic fertilizer promoted greater biomass yield as well as higher accumulation capacity of Pb. In Pb-spiked treatments, roots accumulated more than 85% of total plant Pb which implies that kenaf root can be an important sink for bioavailable Pb. Scanning transmission electron microscope (STEM) X-ray microanalysis confirmed that electron-dense deposits located along cell walls of kenaf roots were Pb precipitates. The ability of kenaf to tolerate Pb and avoid phytotoxicity could be attributed to the immobilization of Pb in the roots and hence the restriction of upward movement (tr...
Acacia mangium Willdenow and Acacia auriculiformis A. Cunningham ex Bentham are fast-growing spec... more Acacia mangium Willdenow and Acacia auriculiformis A. Cunningham ex Bentham are fast-growing species with wide environmental adaptability. Fast-growing species which thrive in otherwise non-arable problematic soil and which hold the added advantage of improving the condition of the soil, can be used to increase production area, and, thus, are highly desired. We investigated the growth performance and lignin content under normal and stressed conditions for these Acacia mangium Willd. and Acacia auriculiformis A. Cunn. ex Benth. Normal growing conditions was represented by fertile soil, high water-holding capacity due to low soil drainage, high organic matter, low soil temperature, overall consistent rainfall and relatively milder temperatures, whilst stressed conditions were achieved with a sandy soil with low fertility, low water-holding capacity due to high drainage and low organic matter, and high soil temperature accompanied by inconsistent monthly temperature and rainfall. Growt...
Net photosynthetic rate (Pn), stomatal conductance (Gw), water use efficiency (WUE), and osmotic ... more Net photosynthetic rate (Pn), stomatal conductance (Gw), water use efficiency (WUE), and osmotic potential (ψ s0) were studied for 46 tropical tree species, including 24 tree species found in Pasoh Forest Reserve, in order to clarify their ecophysiological traits. The maximum value of Pn (Pnmax) varied from 2.5 to 24.2µmolCO2 m-2s-1 with an average of 9.1µmolCO2 m-2 s-1. The maximum value of Gw (Gwmax) varied from 30 to 1,300 molH2O m-2 s-1 with an average of 340 mmolH2O m-2 s-1. These values were relatively low compared to those of temperate tree species. Intrinsic water-use efficiency (IWUE, Pnmax/Gwmax) of the tropical species was also relatively low compared to the temperate tree species. ψ s0 of the tropical species was relatively high (less negative) compared to the temperate tree species, suggesting that the capacity of leaves to maintain positive turgor is relatively low in the tropical species. The lower photosynthetic rate in the tropical species was due not only to lower stomatal conductance, but also to lower photosynthetic efficiency, compared to the temperate species. The rapid growth of tropical tree species may be due to favorable environmental factors such as relatively constant temperature and moisture levels, which permit photosynthesis all the year-round.
Rain forest trees with various light requirements exhibit a high variation in their physiology an... more Rain forest trees with various light requirements exhibit a high variation in their physiology and morphology as they encounter contrasting light environments, contributing to higher leaf carbon gain in each environment. A desire to understand the species-specific variations of capturing and using of light resources in terms of photosynthetic processes provides the setting for this chapter. Both niche partitioning and chance effects in the distribution of tropical trees are widely recognized. The objective of this chapter is to clarify tree responses at the single leaf and whole plant levels for the spatial and temporal changes of lights, providing an improved background of ideas on rain forest dynamics and coexistence and an improved plan for the sustainable forest management and conservation. Recent evidences that the ecophysiological adjustments of plant to changing lights influence replacement success under the changing environments and tropical forest dynamics, are reviewed briefly.
AbstractContamination of heavy metals in tin tailings has caused an interest in the scientific .... more AbstractContamination of heavy metals in tin tailings has caused an interest in the scientific ... of the four timber species is having economic potential for remediation of soil Pb and ... The occurrence of some important potentially toxic trace elements in an ex-mining land located in ...
... Page 476. 460 Dipterocarp Forest Ecosystems: Towards Sustainable Management References AHMAD ... more ... Page 476. 460 Dipterocarp Forest Ecosystems: Towards Sustainable Management References AHMAD SAID SAJAP, FAZALI ABDUL KADER, MOHD SHAHWAUD HJ. OTHMAN, AMINUDDIN MOHAMED, FARIDAH HANUM IBRAHIM and MOHD HAMAMI SAHRI (1992). ...
Proyecto de demostración de reforestación en minas de estaño abandonadas y desarboladas en Malays... more Proyecto de demostración de reforestación en minas de estaño abandonadas y desarboladas en Malaysia peninsular
The potential of kenaf (Hibiscus cannabinus L.) for phytoremediation of lead (Pb) on sand tailing... more The potential of kenaf (Hibiscus cannabinus L.) for phytoremediation of lead (Pb) on sand tailings was investigated. A pot experiment employing factorial design with two main effects of fertilizer and lead was conducted in a nursery using sand tailings from an ex-tin mine as the growing medium. Results showed that Pb was found in the root, stem, and seed capsule of kenaf but not in the leaf. Application of organic fertilizer promoted greater biomass yield as well as higher accumulation capacity of Pb. In Pb-spiked treatments, roots accumulated more than 85% of total plant Pb which implies that kenaf root can be an important sink for bioavailable Pb. Scanning transmission electron microscope (STEM) X-ray microanalysis confirmed that electron-dense deposits located along cell walls of kenaf roots were Pb precipitates. The ability of kenaf to tolerate Pb and avoid phytotoxicity could be attributed to the immobilization of Pb in the roots and hence the restriction of upward movement (tr...
Acacia mangium Willdenow and Acacia auriculiformis A. Cunningham ex Bentham are fast-growing spec... more Acacia mangium Willdenow and Acacia auriculiformis A. Cunningham ex Bentham are fast-growing species with wide environmental adaptability. Fast-growing species which thrive in otherwise non-arable problematic soil and which hold the added advantage of improving the condition of the soil, can be used to increase production area, and, thus, are highly desired. We investigated the growth performance and lignin content under normal and stressed conditions for these Acacia mangium Willd. and Acacia auriculiformis A. Cunn. ex Benth. Normal growing conditions was represented by fertile soil, high water-holding capacity due to low soil drainage, high organic matter, low soil temperature, overall consistent rainfall and relatively milder temperatures, whilst stressed conditions were achieved with a sandy soil with low fertility, low water-holding capacity due to high drainage and low organic matter, and high soil temperature accompanied by inconsistent monthly temperature and rainfall. Growt...
Net photosynthetic rate (Pn), stomatal conductance (Gw), water use efficiency (WUE), and osmotic ... more Net photosynthetic rate (Pn), stomatal conductance (Gw), water use efficiency (WUE), and osmotic potential (ψ s0) were studied for 46 tropical tree species, including 24 tree species found in Pasoh Forest Reserve, in order to clarify their ecophysiological traits. The maximum value of Pn (Pnmax) varied from 2.5 to 24.2µmolCO2 m-2s-1 with an average of 9.1µmolCO2 m-2 s-1. The maximum value of Gw (Gwmax) varied from 30 to 1,300 molH2O m-2 s-1 with an average of 340 mmolH2O m-2 s-1. These values were relatively low compared to those of temperate tree species. Intrinsic water-use efficiency (IWUE, Pnmax/Gwmax) of the tropical species was also relatively low compared to the temperate tree species. ψ s0 of the tropical species was relatively high (less negative) compared to the temperate tree species, suggesting that the capacity of leaves to maintain positive turgor is relatively low in the tropical species. The lower photosynthetic rate in the tropical species was due not only to lower stomatal conductance, but also to lower photosynthetic efficiency, compared to the temperate species. The rapid growth of tropical tree species may be due to favorable environmental factors such as relatively constant temperature and moisture levels, which permit photosynthesis all the year-round.
Rain forest trees with various light requirements exhibit a high variation in their physiology an... more Rain forest trees with various light requirements exhibit a high variation in their physiology and morphology as they encounter contrasting light environments, contributing to higher leaf carbon gain in each environment. A desire to understand the species-specific variations of capturing and using of light resources in terms of photosynthetic processes provides the setting for this chapter. Both niche partitioning and chance effects in the distribution of tropical trees are widely recognized. The objective of this chapter is to clarify tree responses at the single leaf and whole plant levels for the spatial and temporal changes of lights, providing an improved background of ideas on rain forest dynamics and coexistence and an improved plan for the sustainable forest management and conservation. Recent evidences that the ecophysiological adjustments of plant to changing lights influence replacement success under the changing environments and tropical forest dynamics, are reviewed briefly.
AbstractContamination of heavy metals in tin tailings has caused an interest in the scientific .... more AbstractContamination of heavy metals in tin tailings has caused an interest in the scientific ... of the four timber species is having economic potential for remediation of soil Pb and ... The occurrence of some important potentially toxic trace elements in an ex-mining land located in ...
... Page 476. 460 Dipterocarp Forest Ecosystems: Towards Sustainable Management References AHMAD ... more ... Page 476. 460 Dipterocarp Forest Ecosystems: Towards Sustainable Management References AHMAD SAID SAJAP, FAZALI ABDUL KADER, MOHD SHAHWAUD HJ. OTHMAN, AMINUDDIN MOHAMED, FARIDAH HANUM IBRAHIM and MOHD HAMAMI SAHRI (1992). ...
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