勃氏甜龙竹笋苗兼用林林分结构优化模式初步研究

勃氏甜龙竹是一种优良的多用途竹种,近年来在许多适生区得到推广,其资源扩繁主要依赖于母竹移植。研究应用竹子生理整合性等生态学原理,以竹林林分结构调控为核心技术,采用不同林分结构组合,旨在探求笋苗兼用竹林经营模式。结果表明:(1)新造竹林有一明显的出笋数量和笋个体质量增长期,时间区段不同,前3a均快速增长,然后笋个体质量相对稳定,出笋数量仍较快增长。(2)竹笋产量主要影响因子是丛立竹数和立竹胸径,决定出笋数量和笋个体质量。出笋数量与丛立竹数正相关,与笋个体质量负相关。胸径与笋个体质量正相关,与出笋数量无相关。(3)合理的林分结构在450丛·hm-2时,丛立竹数为10株左右,胸径4～6cm。(4)经营类型经济效益明显,新造竹林第2年即有产出,第4年进入丰产期。

Study on Structure Optimization of Dendrocalamus brandisii Shoot and Stock-Producing Stand

Dendrocalamus brandisii,an excellent bamboo species,has been extended in many adapted areas in china,and the main propagation method is to transplant by clone.Based on ecological theories about physiological integration characteristics and taking structure adjustment of bamboo stand as key technique,different stand composition patterns were adopted to probe into the optimal management patterns for shoot and stock-producing stands.The results of study are as follows:(1)New-built bamboo stand had a distinct period when the quantity and quality of shoot increased rapidly.In the first 3 years,both the quantity and quality of shoot increased rapidly,then the individual quality of shoot kept stable while the quantity kept increasing.(2)The key factors affecting the yield of shoot were the quantity and DBH of living culm,which determined the quantity and quality of shoot.The quantity of shoot product was positively correlated with the quantity of living culm,and negatively correlated with the quality of individual shoot.The dbh was positively correlated with the individual quality of living culm and was not correlated with the quantity of shoot.(3)With the optimal stand structure,when the stand density was 450 culms per hectare,the clumping living bamboo should be 10 culms with dbh 4-6 cm.(4)The economic benefits of management was obvious.The bamboo stand began to produce shoot and stock in the next year after the bamboo stand was established and entered high-yielding period from the 4th year on.