文献类型：期刊文献

中文题名：米老排人工林天然更新及影响因子

英文题名：Natural regeneration and influencing factors of Mytilaria laosensis plantation

作者：唐继新[1,2] 李忠国[1] 马跃[1] 曾冀[1] 安宁[1] 陈东成[1]

第一作者：唐继新

机构：[1]中国林业科学研究院热带林业实验中心,广西凭祥532600;[2]广西友谊关森林生态系统国家定位观测研究站,广西凭祥532600

年份：2020

卷号：51

期号：4

起止页码：897-904

中文期刊名：南方农业学报

外文期刊名：Journal of Southern Agriculture

收录：CSTPCD;;北大核心:【北大核心2017】；CSCD:【CSCD_E2019_2020】；

基金：广西自然科学基金项目(2016GXNSFBA380087);中国林业科学研究院热带林业实验中心科学基金项目(RL2012-01);全国森林经营科技支撑科研专项(1692017-1)。

语种：中文

中文关键词：米老排人工林;天然更新;遮荫处理;种子萌发;化感作用

外文关键词：Mytilaria laosensis plantation;natural regeneration;shading treatment;seed germination;allelopathic effects

分类号：S754

摘要：【目的】探索米老排人工林天然更新的机理,为其天然更新的利用和人工促进措施提供科学依据。【方法】基于米老排人工林天然更新环境因子的调查及米老排种子萌发的控制性试验,采用单因素方差分析及最小显著差异法(LSD)分析光照(CK1,自然全光照,T1~T4处理分别为1~4层遮荫,37.3%、15.5%、4.2%和1.6%自然光照)、凋落物物理性质(覆盖方式)(A1和A2处理,种子分别在凋落物下方和上方)、凋落物浸提液浓度差异对米老排天然更新的影响。【结果】郁闭米老排人工林中,无论是米老排树种或其他树种天然更新的效果均不良[幼树(树高h>1.3 m)的更新密度<330.0株/ha,更新频度<13.0%]。林下微环境类型对米老排天然更新的影响明显,其微环境类型更新频度的排序为裸露地表>草本>凋落物>岩石,在凋落物覆盖的微环境中,其更新频度低于30.0%。在不同遮荫处理中,米老排种子的最终萌发率、萌发指数和萌发初始日的差异不显著(P>0.05,下同)。凋落物覆盖对米老排种子萌发的效果(萌发率、发芽势、萌发指数、平均萌发时间)影响不显著,但种子萌发起始日均大于CK1;种子处于凋落物上方的A2处理,其萌发率、平均萌发时间、萌发指数和萌发起始日与对照均有显著差异(P<0.05)。米老排凋落物浸提液对米老排种子萌发有“低促高抑”化感作用,其中,高浓度浸提液(B1处理)对种子的萌发率、发芽势和萌发指数有强烈抑制作用(|RI|>0.50),低浓度浸提液(B2、B3和B4处理)对种子的萌发率、发芽势和萌发指数的化感作用为微弱等级(|RI|≤0.30)。【结论】种子萌发受凋落物隔离的物理障碍作用显著;光照不是影响米老排种子萌发的限制性因子,而是米老排幼树建成的关键影响因子;高浓度的凋落物浸提液对米老排种子萌发、幼苗胚根的生长及胚根与胚轴比值有显著抑制作用。因此,米老排凋落物的物理机械障碍是阻碍其种子萌发及幼苗定居的关键因子。
【Objective】To explore the mechanism of natural regeneration of Mytilaria laosensis plantation,and then provide a scientific basis for utilization and artificial promotion measures of natural regeneration of M.laosensis plantation.【Method】The effects of light(CK1,natural light,T1-T4 were one to four layers of shade with 37.3%,15.5%,4.2%and 1.6%natural full light),physical features of litter(mulching methods)(A1 and A2 treatments:seeds were under and above the litters respectively)and extraction concentration of litter on natural regeneration of M.laosensis were analyzed by single factor analysis of variance and the least significant difference(LSD),based on investigation of natural regeneration of the plantation effected by environment factor,and control test of seed germination of M.laosensis.【Result】Under closed stand of the plantation,neither M.laosensis species nor other tree species had good level of natural regeneration[natural regeneration density of seed sapling(tree hight h>1.3 m)was<330.0 plant/ha,sapling regeneration frequency was<13.0%].It also was effected obvious by the microenvironment type under the forest.The regeneration frequency ranking from high to low in the microenvironment was as follows:bare land>herbaceous>litter>rock.In the microenvironment covered by litter,the regeneration frequency was<30.0%.There were no significant differences(P>0.05,the same below)in the final germination percentage,germination index and initial germination days of the seed under different shading treatments.Litter mulching had no significant influence on the germination effect(germination percentage,germination energy,germination index and average germination time)of the seed.But the initial germination days were longer than CK1.In A2 treatment(seed was above litters),the germination rate,the average germination time,the germination index and the germination initial days of the seeds were significantly different from those of the control(P<0.05).Litter extraction had allelopathic effects on the germination of the seed,high concentration extract(B1 treatment)had a strong inhibitory effect on the germination percentage,germination energy and germination index of seeds(|RI|>0.50),while low concentration extract(B2,B3 and B4 treatments)had a weak allelopathic effect on the germination percentage,germination energy and germination index of seeds(|RI|≤0.30).【Conclusion】The germination of M.laosensis seed is significantly affected by the physical and mechanical barrier of isolation of litter.Illumination is not the limited factor for the seed germination,but it is the key factor for sapling formation.High concentration of litter extract has significant inhibition effects on seed germination,growth of radicle and radicle-plumular axis ratio.Therefore,the litter physical and mechanical obstacles of M.laosensis is the key factor to hindering the seed germination and seedling settlement.