Allometric models are necessary for estimating biomass in terrestrial ecosystems. Generalized allometric relationship exists for many tropical trees, but species- and region-specific models are often lacking. We devel...Allometric models are necessary for estimating biomass in terrestrial ecosystems. Generalized allometric relationship exists for many tropical trees, but species- and region-specific models are often lacking. We developed species-specific allometric models to predict aboveground biomass for 11 native tree species of the Sudanian savanna- woodlands. Diameters at the base and at breast height, with species means ranging respectively from 11 to 28 cm and 9 to 19 cm, and the height of the trees were used as predictor variables. Sampled trees spanned a wide range of sizes including the largest sizes these species can reach. As a response variable, the biomass of the trees was obtained through destructive sampling of 4 754 trees during wood harvesting. We used a stepwise multiple regression analysis with backward elimination procedure to develop models separately predicting, total biomass of the trees, stem biomass, and biomass of branches and twigs. All species- specific regression models relating biomass with measured tree dimen- sions were highly significant （p 〈 0.001）. The biomass of branches and twigs was less predictable compared to stem biomass and total biomass, although their models required fewer predictors and predictor interac- tions. The best-fit equations for total above-ground biomass and stem biomass bad R2 〉 0.70, except for the Acacia species; for branches including twig biomass, R2-values varied from 0.749 for Anogeissus leiocarpa to 0.183 for Acacia macrostachya. The use of these equations in estimating available biomass will avoid destructive sampling, and aid in planning for sustainable use of these species.展开更多
Dear Editor,Although simple sequence repeat（SSR）markers are not new,they are still useful and often used markers in molecular mapping and marker-assisted breeding,particularly in developing countries.However,locus-s...Dear Editor,Although simple sequence repeat（SSR）markers are not new,they are still useful and often used markers in molecular mapping and marker-assisted breeding,particularly in developing countries.However,locus-specific SSR markers could be more useful and informative in wheat breeding and genetic studies.In the present study,221,911 locus-specific SSR markers were designed.Verification of polymorphisms showed that the proportion of polymorphic markers increases with an increase in SSR size.展开更多
基金provided by Swedish International Development Cooperation Agency (Sida)
文摘Allometric models are necessary for estimating biomass in terrestrial ecosystems. Generalized allometric relationship exists for many tropical trees, but species- and region-specific models are often lacking. We developed species-specific allometric models to predict aboveground biomass for 11 native tree species of the Sudanian savanna- woodlands. Diameters at the base and at breast height, with species means ranging respectively from 11 to 28 cm and 9 to 19 cm, and the height of the trees were used as predictor variables. Sampled trees spanned a wide range of sizes including the largest sizes these species can reach. As a response variable, the biomass of the trees was obtained through destructive sampling of 4 754 trees during wood harvesting. We used a stepwise multiple regression analysis with backward elimination procedure to develop models separately predicting, total biomass of the trees, stem biomass, and biomass of branches and twigs. All species- specific regression models relating biomass with measured tree dimen- sions were highly significant （p 〈 0.001）. The biomass of branches and twigs was less predictable compared to stem biomass and total biomass, although their models required fewer predictors and predictor interac- tions. The best-fit equations for total above-ground biomass and stem biomass bad R2 〉 0.70, except for the Acacia species; for branches including twig biomass, R2-values varied from 0.749 for Anogeissus leiocarpa to 0.183 for Acacia macrostachya. The use of these equations in estimating available biomass will avoid destructive sampling, and aid in planning for sustainable use of these species.
基金supported by the National Natural Science Foundation of China(31270704,31600997)the Yangzhou Key Research and Development Program(YZ2016035)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘Dear Editor,Although simple sequence repeat（SSR）markers are not new,they are still useful and often used markers in molecular mapping and marker-assisted breeding,particularly in developing countries.However,locus-specific SSR markers could be more useful and informative in wheat breeding and genetic studies.In the present study,221,911 locus-specific SSR markers were designed.Verification of polymorphisms showed that the proportion of polymorphic markers increases with an increase in SSR size.
