This study aimed to model and identify the most productive cutting methods of tree plantations by comparing a forward felling technique(C)with sideways techniques outside(A and D)or inside cutting edge(B and E).Drone ...This study aimed to model and identify the most productive cutting methods of tree plantations by comparing a forward felling technique(C)with sideways techniques outside(A and D)or inside cutting edge(B and E).Drone video material of each tree was analyzed by comparing time distribution of work phases.The relation between this input data and harvester production data was analyzed by regression models.A quadratic model predicted productiv-ity precisely(R^(2)=0.95)and explained the effective-hour productivity in cutting cycle with dummy variables of har-vesting conditions.The productivity was explained by tree size and cutting cycle time,while effects of operator and harvester were eliminated by statistical analysis.In loblolly pine(Pinus taeda L.)plantations on flat terrain,cutting method B was 4.8 m3/E0h(effective working hour)more productive than method A,and 6.7 m^(3)/E0h than method C.In Sydney blue gum(Eucalyptus saligna Sm.)plantations,cutting method E was 1.8 m^(3)/E0h more productive than cut-ting method D on sloping terrain.Of the time-cycle vari-ables,time consumption of the“moving of tree”changed significantly between the cutting methods,of which the ones that used the sideways felling technique inside cutting edge were most efficient.This quadratic modeling structure can be recommended for precise studies in similar harvesting conditions.展开更多
White rot fungus Pleurotus djamor H1 was stilly cultured at 28 ℃ under 4 different kinds of LNAS culture solution,the extracellular enzyme solutions were sampled at different interval,O.D.values of the solutions,repr...White rot fungus Pleurotus djamor H1 was stilly cultured at 28 ℃ under 4 different kinds of LNAS culture solution,the extracellular enzyme solutions were sampled at different interval,O.D.values of the solutions,representing manganese peroxidase(MnP),laccase and lignin peroxidase(LiP)activities,were measured spectrophotometrically by monitoring the oxidation of 2,6-DMP at 470 nm,ABTS at 420 nm and veratryl alcohol(VA)at 310 nm,the lignin-degrading enzymes of the fungus and the relationships between enzyme activities and medium composition and substrates were gained.Results indicated that Pleurotus djamor could produce MnP and laccase simultaneously,but no Lip.Substrates wood sawdust and 2,6-DMP could significantly enhanced MnP and laccase activities,the biggest Mnp and laccase activity were 5 U·L-1.and 38 U·L-1 when no substrates were added,and 69 U·L-1 and 205 U·L-1 when substrates added.The paper offered a basic ligninolytic enzymology of Pleurotus djamor for future utilization of the enzymes and further study on MnP and laccase mechanism of the fungus.展开更多
文摘This study aimed to model and identify the most productive cutting methods of tree plantations by comparing a forward felling technique(C)with sideways techniques outside(A and D)or inside cutting edge(B and E).Drone video material of each tree was analyzed by comparing time distribution of work phases.The relation between this input data and harvester production data was analyzed by regression models.A quadratic model predicted productiv-ity precisely(R^(2)=0.95)and explained the effective-hour productivity in cutting cycle with dummy variables of har-vesting conditions.The productivity was explained by tree size and cutting cycle time,while effects of operator and harvester were eliminated by statistical analysis.In loblolly pine(Pinus taeda L.)plantations on flat terrain,cutting method B was 4.8 m3/E0h(effective working hour)more productive than method A,and 6.7 m^(3)/E0h than method C.In Sydney blue gum(Eucalyptus saligna Sm.)plantations,cutting method E was 1.8 m^(3)/E0h more productive than cut-ting method D on sloping terrain.Of the time-cycle vari-ables,time consumption of the“moving of tree”changed significantly between the cutting methods,of which the ones that used the sideways felling technique inside cutting edge were most efficient.This quadratic modeling structure can be recommended for precise studies in similar harvesting conditions.
文摘White rot fungus Pleurotus djamor H1 was stilly cultured at 28 ℃ under 4 different kinds of LNAS culture solution,the extracellular enzyme solutions were sampled at different interval,O.D.values of the solutions,representing manganese peroxidase(MnP),laccase and lignin peroxidase(LiP)activities,were measured spectrophotometrically by monitoring the oxidation of 2,6-DMP at 470 nm,ABTS at 420 nm and veratryl alcohol(VA)at 310 nm,the lignin-degrading enzymes of the fungus and the relationships between enzyme activities and medium composition and substrates were gained.Results indicated that Pleurotus djamor could produce MnP and laccase simultaneously,but no Lip.Substrates wood sawdust and 2,6-DMP could significantly enhanced MnP and laccase activities,the biggest Mnp and laccase activity were 5 U·L-1.and 38 U·L-1 when no substrates were added,and 69 U·L-1 and 205 U·L-1 when substrates added.The paper offered a basic ligninolytic enzymology of Pleurotus djamor for future utilization of the enzymes and further study on MnP and laccase mechanism of the fungus.
