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Dan Binkley - One of the best experts on this subject based on the ideXlab platform.
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soil phosphorus pools and supply under the influence of eucalyptus saligna and nitrogen fixing Albizia facaltaria
Forest Ecology and Management, 2000Co-Authors: Dan Binkley, Chistian Giardina, Michael A BashkinAbstract:Replicated plantations of Eucalyptus saligna (Sm.) and Albizia falcataria (L.) Fosberg were examined for patterns in soil phosphorus (P) fractions and soil P availability. The supply of P was assessed in the field with anion exchange resin bags, which indicated that P supply was about twice as high under Eucalyptus as under Albizia. In the laboratory, solution P extracted with iron oxide-impregnated paper strips was also 45% higher under Eucalyptus. The effects of mixtures of the two species were intermediate between the pure-species effects. Overall, P supply either increased with Eucalyptus or decreased under Albizia. Despite significantly lower soil P availability, the Albizia plots appeared to take up and cycle as much P as the Eucalyptus plots, indicating that P supply was not independent of P demand. High rates of P uptake by Albizia may depend on higher allocations of carbohydrate to belowground production.
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Net primary production and nutrient cycling in replicated stands of Eucalyptus saligna and Albizia facaltaria
Forest Ecology and Management, 1998Co-Authors: Dan Binkley, Michael G. RyanAbstract:Production and nutrient cycling budgets were estimated at three locations within 1 km on the island of Hawaii, for replicated plantations of Eucalyptus saligna Sm. and nitrogen-fixing Albizia facaltaria (L.) Fosberg (aParaserianthes facaltaria (L.) Nielson)). At the age of 16 years, the aboveground biomass of Eucalyptus averaged 323 Mg/ha, about 50% more than the 216 Mg/ha of Albizia biomass. Net primary production (NPP) was about 40 Mg ha ˇ1 year ˇ1 for both species. Eucalyptus allocated 45% of NPP to stem production, compared with 34% of Albizia (pa0.02). Conversely, Eucalyptus allocated less production belowground (29% of NPP) than did Albizia (41% of NPP, p
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net primary production and nutrient cycling in replicated stands of eucalyptus saligna and Albizia facaltaria
Forest Ecology and Management, 1998Co-Authors: Dan Binkley, Michael G. RyanAbstract:Production and nutrient cycling budgets were estimated at three locations within 1 km on the island of Hawaii, for replicated plantations of Eucalyptus saligna Sm. and nitrogen-fixing Albizia facaltaria (L.) Fosberg (aParaserianthes facaltaria (L.) Nielson)). At the age of 16 years, the aboveground biomass of Eucalyptus averaged 323 Mg/ha, about 50% more than the 216 Mg/ha of Albizia biomass. Net primary production (NPP) was about 40 Mg ha ˇ1 year ˇ1 for both species. Eucalyptus allocated 45% of NPP to stem production, compared with 34% of Albizia (pa0.02). Conversely, Eucalyptus allocated less production belowground (29% of NPP) than did Albizia (41% of NPP, p<0.01). Litterfall mass did not differ between species, but differences in litterfall nutrient concentrations led to greater litterfall cycling of N and P for Albizia than for Eucalyptus (141 vs. 105 kg N ha ˇ1 ; 6.2 vs. 4.8 kg P ha ˇ1 year ˇ1 ). The rate of N cycling in the aboveground-increment plus litterfall did not differ significantly between species. Lower soil P supply under Albizia may be partially responsible for the high ratio of belowground:aboveground production for Albizia. The mean annual increment (MAI) of aboveground biomass of Eucalyptus for 16 years was 20.2 Mg ha ˇ1 year ˇ1 , which is not different from the annual increment of 19.3 Mg ha ˇ1 year ˇ1 between the age of 14 and 16 years. The MAI for Albizia (13.5 Mg ha ˇ1 year ˇ1 ) also matched the annual increment (13.9 Mg ha ˇ1 year ˇ1 ) from ages 14‐16. The sustained high productivity of these stands may warrant longer rotation periods than currently recommended, especially on fertile soils or in silvicultural systems with high rates of fertilization. # 1998 Elsevier Science B.V. All rights reserved.
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effect of eucalyptus saligna and Albizia falcataria on soil processes and nitrogen supply in hawaii
Oecologia, 1998Co-Authors: D C Garciamontiel, Dan BinkleyAbstract:This study investigated the differences between two fast-growing tropical tree species on soil N flux and availability. The work was conducted in the island of Hawaii and included three sites located along the Hamakua coast on the northeastern side of the island. Within each site pure stands of Eucalyptus saligna (Sm.)␣and the N2-fixing Albizia falcataria (L.) Fosberg [=Paraserianthes falcataria (L.) Nielsen] were arranged in four randomized complete blocks. For most of the variables considered in this study, the species effects were usually strong and the site effects were significant in some cases. After 13 years, soils under the Albizia stand contained larger pools of total soil C and N, and larger pools of inorganic N. Soil N availability indexed by ion exchange resin bags revealed a strong pattern of species and site effect on N availability; soils under Albizia showed a 2.6–9 fold increase in N availability (P < 0.01). Potential net rates of N transformation (10- and 30-day aerobic incubations) were more than twice as high for soils under the Albizia than under the Eucalytus stands. Nitrogen mineralization during anaerobic incubations were about 10% greater on Albizia soils. Gross microbial mineralization and immobilization were determined by estimating the gross rates of N transformation by the 15N-isotope pool dilution techniques. Across species and sites, a strong linear positive relationship was obtained for gross immobilization and gross mineralization indicating faster gross immobilization as gross mineralization increases. Soil microbial biomass on Albizia soils contained larger proportion of it as bacterial biomass, while larger proportion of fungi biomass comprised the microbial biomass under Eucalyptus soils. This study clearly showed that the presence of Albizia increased total N pools and N supply to the ecosystem. The overall effect on soil fertility will need to be characterized by the effect of the N2-fixer on other nutrients, especially the effect on phosphorus.
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bioassays of the influence of eucalyptus saligna and Albizia falcataria on soil nutrient supply and limitation
Forest Ecology and Management, 1997Co-Authors: Dan BinkleyAbstract:Abstract Replicated plantations of Eucalyptus saligna (Sm.) and Albizia falcataria (L.) Fosberg [ = Paraserianthes falcataria (L.) Nielsen] in Hawaii allowed an assessment of 12 years of influence of each species on soil fertility. Bioassays with Eucalyptus and Albizia seedlings showed that each species of seedling grew better in soil from the plantations with the other species. The nutrient content of seedlings showed that soils under the influence of Albizia had higher supplies of available N, but lower supplies of available P. Albizia seedlings were strongly limited by P supply in the soils from either species, whereas the growth of Eucalyptus seedlings was limited by both N and P. Albizia seedlings fixed > 95% of the N they used, and took up less soil N than did Eucalyptus seedlings. The overall pattern indicated that Albizia increased soil N supply and growth of Eucalyptus seedlings, although the higher supply of N was not enough to remove N limitation on growth. Albizia also reduced the P supply of the soil, and Albizia seedlings were strongly P-limited regardless of the plantation species. The long-term productivity of tropical plantations depends on continued supplies of nutrients, and these supplies may be strongly influenced by the species selected for plantation use.
Wen Xin Chen - One of the best experts on this subject based on the ideXlab platform.
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mesorhizobium Albiziae sp nov a novel bacterium that nodulates Albizia kalkora in a subtropical region of china
International Journal of Systematic and Evolutionary Microbiology, 2007Co-Authors: Feng-qin Wang, En Tao Wang, Wen-feng Chen, Qiang Chen, Wen Xin ChenAbstract:A novel Mesorhizobium group associated with Albizia kalkora [ Wang et al. (2006) , Syst Appl Microbiol 29, 502–517] was further characterized. The seven strains in this group showed similar protein patterns and were different from defined Mesorhizobium species in SDS-PAGE of whole-cell proteins. The representative strain CCBAU 61158T formed a novel Mesorhizobium lineage in phylogenetic analyses of 16S rRNA, atpD, glnII and nifH genes. However, its nodC gene sequence was more similar to that of Rhizobium gallicum R602spT than to those of Mesorhizobium species. DNA–DNA relatedness between CCBAU 61158T and reference strains of defined Mesorhizobium species was lower than 34.1 %. These results indicated that this Mesorhizobium group was a unique genomic species. The subtropical distribution, host origin, PCR-RFLP patterns of 16S rRNA genes, fatty acid profile and a series of phenotypic characteristics could be used as distinctive features of this group. This group is therefore proposed as a novel species, Mesorhizobium Albiziae sp. nov., with CCBAU 61158T (=LMG 23507T=USDA 4964T) as the type strain. Strain CCBAU 61158T could form effective nodules on Albizia julibrissin, Glycine max, Leucaena leucocephala and Phaseolus vulgaris.
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characterization of rhizobia isolated from Albizia spp in comparison with microsymbionts of acacia spp and leucaena leucocephala grown in china
Systematic and Applied Microbiology, 2006Co-Authors: Feng-qin Wang, En Tao Wang, Yongfa Zhang, Wen Xin ChenAbstract:This is the first systematic study of rhizobia associated with Albizia trees. The analyses of PCR-RFLP and sequencing of 16S rRNA genes, SDS–PAGE of whole-cell proteins and clustering of phenotypic characters grouped the 31 rhizobial strains isolated from Albizia into eight putative species within the genera Bradyrhizobium, Mesorhizobium and Rhizobium. Among these eight rhizobial species, five were unique to Albizia and the remaining three were shared with Acacia and Leucaena, two legume trees coexisting with Albizia in China. These results indicated that Albizia species nodulate with a wide range of rhizobial species and had preference of microsymbionts different from Acacia and Leucaena. The definition of four novel groups, Mesorhizobium sp., Rhizobium sp. I, Rhizobium sp. II and “R. giardinii”, indicates that further studies with enlarged rhizobial population are necessary to better understand the diversity and to clarify the taxonomic relationships of Albizia-associated rhizobia.
Feng-qin Wang - One of the best experts on this subject based on the ideXlab platform.
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mesorhizobium Albiziae sp nov a novel bacterium that nodulates Albizia kalkora in a subtropical region of china
International Journal of Systematic and Evolutionary Microbiology, 2007Co-Authors: Feng-qin Wang, En Tao Wang, Wen-feng Chen, Qiang Chen, Wen Xin ChenAbstract:A novel Mesorhizobium group associated with Albizia kalkora [ Wang et al. (2006) , Syst Appl Microbiol 29, 502–517] was further characterized. The seven strains in this group showed similar protein patterns and were different from defined Mesorhizobium species in SDS-PAGE of whole-cell proteins. The representative strain CCBAU 61158T formed a novel Mesorhizobium lineage in phylogenetic analyses of 16S rRNA, atpD, glnII and nifH genes. However, its nodC gene sequence was more similar to that of Rhizobium gallicum R602spT than to those of Mesorhizobium species. DNA–DNA relatedness between CCBAU 61158T and reference strains of defined Mesorhizobium species was lower than 34.1 %. These results indicated that this Mesorhizobium group was a unique genomic species. The subtropical distribution, host origin, PCR-RFLP patterns of 16S rRNA genes, fatty acid profile and a series of phenotypic characteristics could be used as distinctive features of this group. This group is therefore proposed as a novel species, Mesorhizobium Albiziae sp. nov., with CCBAU 61158T (=LMG 23507T=USDA 4964T) as the type strain. Strain CCBAU 61158T could form effective nodules on Albizia julibrissin, Glycine max, Leucaena leucocephala and Phaseolus vulgaris.
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characterization of rhizobia isolated from Albizia spp in comparison with microsymbionts of acacia spp and leucaena leucocephala grown in china
Systematic and Applied Microbiology, 2006Co-Authors: Feng-qin Wang, En Tao Wang, Yongfa Zhang, Wen Xin ChenAbstract:This is the first systematic study of rhizobia associated with Albizia trees. The analyses of PCR-RFLP and sequencing of 16S rRNA genes, SDS–PAGE of whole-cell proteins and clustering of phenotypic characters grouped the 31 rhizobial strains isolated from Albizia into eight putative species within the genera Bradyrhizobium, Mesorhizobium and Rhizobium. Among these eight rhizobial species, five were unique to Albizia and the remaining three were shared with Acacia and Leucaena, two legume trees coexisting with Albizia in China. These results indicated that Albizia species nodulate with a wide range of rhizobial species and had preference of microsymbionts different from Acacia and Leucaena. The definition of four novel groups, Mesorhizobium sp., Rhizobium sp. I, Rhizobium sp. II and “R. giardinii”, indicates that further studies with enlarged rhizobial population are necessary to better understand the diversity and to clarify the taxonomic relationships of Albizia-associated rhizobia.
Oluwatoyin A Odeku - One of the best experts on this subject based on the ideXlab platform.
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assessment of Albizia zygia gum as a binding agent in tablet formulations
Acta Pharmaceutica, 2005Co-Authors: Oluwatoyin A OdekuAbstract:: Albizia gum has been evaluated as a binding agent in tablet formulations in comparison with gelatin BP. Compressional properties were analyzed using density measurements and the compression equations of Heckel and Kawakita as assessment parameters, while the mechanical properties of the tablets were assessed using the crushing strength and friability of the tablets. Drug release properties of the tablets were assessed using disintegration time and dissolution time as assessment parameters. Formulations containing Albizia gum as a binding agent show a faster onset and higher amount of plastic deformation under compression pressure than those containing gelatin. The crushing strength, disintegration and dissolution times of the tablets increased with increased binder concentration while their friability decreased. Albizia gum produced tablets with better mechanical properties and longer disintegration and dissolution times than those containing gelatin BP. This suggests that Albizia gum could be useful as a binding agent especially when high mechanical strength and slower release rates are desired.
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in vitro evaluation of khaya and Albizia gums as compression coatings for drug targeting to the colon
Journal of Pharmacy and Pharmacology, 2005Co-Authors: Oluwatoyin A Odeku, J T FellAbstract:: Khaya and Albizia gums were evaluated as compression coatings for target drug delivery to the colon using indometacin (a water insoluble drug) and paracetamol (a water soluble drug) as model drugs. The core tablets were compression-coated with 300 and 400 mg of 100% khaya gum, 100% Albizia gum and a mixture of khaya and Albizia gum (1:1). Drug release studies were carried out in 0.1(M) HCl (pH 1.2) for 2 h, Sorensen's buffer (pH 7.4) for 3 h and then in phosphate-buffered saline (pH 6.8) or in simulated colonic fluid for the rest of the experiment to mimic the physiological conditions from the mouth to colon. The results indicated that khaya and Albizia gums were capable of protecting the core tablet in the physiological environment of the stomach and small intestine, with Albizia gum showing greater ability than khaya gum. The release from tablets coated with the mixture of khaya and Albizia gums was midway between the two individual gums, indicating that there was no interaction between the gums. Studies carried out using rat caecal matter in phosphate-buffered saline at pH 6.8 (simulated colonic fluid) showed that the gums were susceptible to degradation by the colonic bacterial enzymes, leading to release of the drug. The results demonstrate that khaya gum and Albizia gum have potential for drug targeting to the colon.
Michael A Bashkin - One of the best experts on this subject based on the ideXlab platform.
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soil phosphorus pools and supply under the influence of eucalyptus saligna and nitrogen fixing Albizia facaltaria
Forest Ecology and Management, 2000Co-Authors: Dan Binkley, Chistian Giardina, Michael A BashkinAbstract:Replicated plantations of Eucalyptus saligna (Sm.) and Albizia falcataria (L.) Fosberg were examined for patterns in soil phosphorus (P) fractions and soil P availability. The supply of P was assessed in the field with anion exchange resin bags, which indicated that P supply was about twice as high under Eucalyptus as under Albizia. In the laboratory, solution P extracted with iron oxide-impregnated paper strips was also 45% higher under Eucalyptus. The effects of mixtures of the two species were intermediate between the pure-species effects. Overall, P supply either increased with Eucalyptus or decreased under Albizia. Despite significantly lower soil P availability, the Albizia plots appeared to take up and cycle as much P as the Eucalyptus plots, indicating that P supply was not independent of P demand. High rates of P uptake by Albizia may depend on higher allocations of carbohydrate to belowground production.
