Introduction Status And Biomass Of Sweden Energy Willow In Different Regions

In this paper,Sweden energr willow seedlings(young trees) were as as research objects . According to the clone types of introduction willow in Yangling,Huanglong,Qiaoshan and Tianjin regions. By selection of standard individual, forst of all ,14 clobes morphological characteristics were analyzed, then, 8 emphases clones of Sweden willow were selcted for the research of phonological phenomenon, stress resistance, growth and biomass etc.. It supply basis for clone optimization and selection suitable habitat,and it had an important guide significance of popularization of Sweden energy willow. and development of energy forest The main results were as follow:(1) The period of germination and leaf expansion were effected by latitude and elevation. The period in Yangling(low latitude and elevation) was ahead of Huanglong and Qiaoshan (high latitude and elevation )and Tianjing (high latitude and low elevation) .Early day of germination in Yangling was prior to Qiaoshan and Huanglong.for 1-3 weeks and beginning of leaf expansion was 2-3 weeks.The period in Tianjing was close to Qiaolong and Huangshang. although climate had difference in four regions,the period of defoliation were almost from September to November .(2) Resistance of willows had difference in different regions. The insect pest was the strictest in Yangling region. The other regions were lighter than Yangling Insect pest of energy willow poison mainly had Stilprotia salicis, Plagiodera versicolora, Holcocerus vicarious aphides, Anomala corpulenta and Anoplophora glabripennis larvae among which Anomala corpulenta and Anoplophora glabripennis larvae strictly harmed root system of willow;The Sweden energy willow had the higher fuel value . Fuel valu of Ruineng C was the highest among 14 varieties and reached 4412.539 cal/g. Others clones was about 4300 cal/g.(3) Ruineng C ,Ruineng E and Ruineng 2 in 8 clones had higher height growth and diameter in four regions. Tianjing was the suitable habitat for the Sweden energy willow.(4) Height and diameter of energy willow showed"s"curve. At growth initial stage, curve gently ascended about the middle ten days of May. At fast-growing period, curve rapidly ascended about May to August.At later stage,when last period of growth come about September to Novermber, ascending tend of curve gradually slowed and reached level; Dynamic curve of leaf number present"parabola"shape. The increasing of leaf number was slower before May.The value of leaf number reached maximum in the middle ten days and the last ten days of August in Shaanxi. However, the value reached maximum about in theten days of August in Tiangjing. After October, the energy willow began defoliation.(5) Ruineng 2, Ruineng C and Ruineng E had higher biomass in four introduction regions. When density of 1-year-old cutting seedling was 60000 individual/hm~2 , 3 clones biomass of ground branches of 3 clones was more than 10.0t/hm~2 ,and in which,Ruineng C reached 13.3t/hm~2.(6) 4-year-seedling Biomass of ground branches of energy willow showed the rule: main branch>primary lateral branch>secondary lateral branch>tertiary lateral branch; The biomass of underground part accorded with the discipline: main root>primary root>fibrous root>secondary root. Biomass of branch ,leaf and root showed general rule: branch>root>leaf.