摘要
研究了中短轮伐期杨树纸浆林LAI的动态变化,LAI与透光率的关系,林分的生物生产力及林分的经济生物量生产.结果表明,LAI随林龄和密度的增大而递增,3个杨树无性系间是NL80351>I69>I72;LAI与透光率的关系可用M.Monsi和T.Saeki修正的消光方程来描述,消光系数为0.818;林分地上部分年净生物生产力与LAI密切相关,其关系可用指数函数来表达;4年生时,不同密度及不同无性系间林分的生物生产力、生物量分配模式存在较大差异,以1111株·hm-2林分的生产力最高,约为500株·hm-2林分的14倍.3个无性系中以NL80351最高,I72杨最低;林分地上部分干木质部、枝木质部及皮的干物质累积趋势可用Richards方程描述.4年生时,作为化学浆材的林分经济生物量是1111>833>625>500株·hm-2,作为磨木浆材的林分经济生物量是500>625>833>1111株·hm-2.无性系间均以NL80351的林分经济生物量最高,I72杨最低.
The study shows that the leaf area index(LAI) of mid and short rotation poplar plantations for pulp timber was increased with increasing planting density and stand age. Among the 3 poplar clones tested, NL 80351 had the highest LAI, I 72 had the lowest one and I 69 was the intermediate. The relationship between LAI and sunlight penetration rate could be described by extinction equation modified by M.Monsi and T.Saeki, and the extinction coefficient was 0.818 . LAI had a close relationship with aboveground annual net biomass production, which could be expressed by exponential function. There existed a great difference of biomass productivity and distribution pattern among stands with different clones and planting densities at 4 years old. The biomass productivity of the stand with 1111 stems·hm -2 was the highest, as 1.4 times as that with 500 stems·hm -2 . NL 80351 had the highest productivity, and I 72 was the lowest. The biomass accumulation trend of stem xylem, branch xylem and bark could be described by Richards model. In different planting densities, the economic biomass for chemical pulp timber was in order of 1111>833>625>500 stem·hm -2 at 4 years old. However, for groundwood pulp timber, it was in order of 500>625>833>1111 stems·hm -2 . Clone NL 80351 had the highest stand economic biomass for both chemical and groundwood pulp timbers, I 72 had the lowest, and I 69 was the intermediate.
出处
《应用生态学报》
CAS
CSCD
1998年第3期225-230,共6页
Chinese Journal of Applied Ecology
基金
国家"八五"重点科技攻关项目
关键词
杨树无性系
纸浆材
LAI
净生物生产力
Poplar clones, Pulp timber, LAI, Net biomass productivity, Economic biomass.