【目的】在揭示无患子冠层合理光环境的基础上进行树体调控技术主要参数的研究，为解决无患子生物质原料林低产问题提供理论和技术支撑。【方法】通过2年无患子自然树体冠层光环境的分区系统测定，设置骨干枝数目、骨干枝开张角度、结果枝数量及交互等试验，以花枝数量和果实产量为指标开展研究。【结果】1)自然树体树冠光环境不合理，内膛光照度仅为空地光照的10%～15%；经过树体结构调整后年均内膛光照度与产量的关系模型为 y=－0.0119x2+5.9263x－565.37(R2=0.73838)，最佳光照度的范围(200～270)×100 lx。2)根据自然树体光照度双峰变化幅度可佐证无患子的主要物候期，5月份为生殖生长前期，急需大量营养，形成第1个光照度高峰；6月份展叶完成，进入果期，光照度形成第1个低谷；8月份逐渐开始落叶，光照度形成第2个高峰即为生理落果期，之后下降并进入平稳阶段。3)依靠不同部位光照度分布比例进行修剪，一般修剪后外围光照度占空地光照度的40%～54%，中部为32%～35%，内膛光照率为27%～31%，可比不处理的光照度提高2～3倍，使得树体内光照利用效果最佳，促进产量提高。4)设置不同的骨干枝数目(留3，4，5骨干枝)、开张角度(30°，45°，60°及90°)以及单位投影面积留枝量(1 m2保留8～20个结果枝)处理，发现：3骨干枝及5骨干枝的辐射状分布可有效提高光照度，为对照的2～3倍；4骨干枝的光照度及产量均处于最低；5骨干枝产量以25%的速率逐年下降，而3骨干枝产量呈现连年稳定的趋势。开张角度90°处理后当年产量最高，但以50%的速率呈现连年下降的趋势，易出现早衰现象；45°处理3年产量一直最低；60°处理后产量及连年光照度稳定变化趋势优于其他处理。单位投影面积保留16～18个结果枝时以347 g·m －2的产量显著高于其余处理。【结论】3骨干枝、60°开张角度和每m2投影面积留16～18结果枝可比其他处理有效提高无患子冠层全年光照度，使之符合最佳光照度范围，并提高无患子结果树产量2～3倍，结论用双因素交互作用试验进行了验证。在形成一套树体管理综合技术的基础上，无患子生物质原料林采取优良品种与高效集约栽培技术为一体的标准化、园艺化、集约化栽培技术体系，可大幅度提高原料林产量。%Objective]In this study,the tree control technology was applied in order to solve low yield of Sapindus mukorossi biodiesel feedstock forest. This paper is focus on revealing tree canopy with improper light intensity,and hence provides the theoretical and technical support.[Method]The light illumination in different parts of naturally growing trees was measured for 2 years. The number of flowers and fruit yield index,controlling opening angle and number of backbone branches, thinning out of fruiting-shoot were measured and two-factor interaction validation was conducted in this research.[Rusult]1) The light intensity of naturally growing trees were unreasonable—the interior canopy light intensity was only 10% to 15% of the space’s. A model was established between light intensity and yield after regulating the canopy structure,y= -0. 011 9x2 +5. 926 3x -565. 37(R2 =0. 738 38) and the best light intensity could range from (200 -270) × 100 lx. 2) The main phenological phases could also be inferred according to double peaks of light intensity of the naturally growing trees’canopy. In May,at the reproductive growth prophase,trees badly need nutrition,and form the first peak of light intensity. In June,in the turning process from the leaves-sprout stage to the fruit-set stage,the light intensity becomes to a lower level. In August,with leaves falling gradually,light intensity increases to the second peak and then enters into a relatively stable phase. 3) Trimming and pruning operations could be determined by different light distribution proportion. Generally speaking,compared with the space’s light intensity,exterior canopy’s is 40% -54%, central canopy’s is 32% -35%,and interior canopy’s is 27% -31% after pruning,which may increase the yield by two or three times and make use of light effectively. 4 ) The experiment was conducted by setting up different backbone branches numbers (3,4,5),opening angles (30 ,45 ,60 ,90 ) and leaving fruiting branches (8 -20). The experimental results showed that the radial distribution of three backbone branches and five backbone branches was able to effectively improve the light by two or three times compared to control. The yield and light intensity of four backbone branches were lowest. The yield of five backbone branches declined at a rate of 25% year by year. However the yield of three backbone branches showed a steady-state trend for several years. As for opening angles,the yield of the 90 treatment was highest in 2013 but decreased in a rate of 50% after first year,suggesting a premature aging phenomenon. With the treatment of 45° opening angle for three years,the annual yield was lowest. The 60° opening angle treatment had stable yield and light intensity and was the best among the all treatments. As for the fruiting branches,the treatment of 16 -18 fruiting branches contributed to the highest yield of 347 g·m -2 .[Conclusion]In general,three backbone branches,60° opening angle and leaving 16 -18 fruiting branches per m2 crown projection area could most effectively improve light intensity and the yield by one or two times,which is consistent with the results of two-factor interaction validation. The findings suggest that standardizing,gardening,intensive cultivation techniques system should be all combined with selecting excellent-genetic S. mukorossi and highly efficient and intensive techniques,so as to form an integrate tree management technology to enhance feedstock forest’s production.
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