A study on calorific value of fuelwood species in the xerothermic valley and in the central yunnan plateau

Since fuelwood forest is mainly to produce heat energy resources,calorific value of fuelwood is an important index of tree species selection for fuelwood forest.For this reason,a determination of the calorific value of fuelwood for 35 treespecies from 4 test sites——Anning,Yixi,Dongchuan,Yuanmou was conducted with GB3 500-B calori-meter for "Researches in Choice of Suitable Tree Species,Techniqueof Forestation and Working Types of Fuelwood Forest in the Central Yunnan Plateauand Xerothermic Vallev of Yunnan Province" that is a strategic item of "8th Five-YearPlan" in 1991~1995The main results were summarized as follows: (1)in theCentral Yunnan plateau,there were 8 tree species——Eucalyptus maideni,E.globulus,Acacia dealbala,Schima wallichii etc.above 18 850 kJ/kg of the calorinc value ofhelwood,there were 9 tree species between 16 750~18 850 kJ/kg of the calorific valueof fuelwood; (2)in Xerothermic valley,there were also 8 tree species──E.camaldulensis,A.suma,A mangium,Robinia pseudoacacia etc above 18 850 kJ/kg there were11 tree species between 16 750~18 850 kJ/kg of the calorific value of fuelwood.Where-as the caloriflc value of fuelwood above tree species is nearly as high as brown coal,itsuggests that above tree species are recommended to extensive planting of fuelwood for-est in the Central Yunnan plateau and Xerothermic vallev of Yunnan Province.