Response of growth and branch development of Betula alnoides young plantation to light environment
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摘要:目的
模拟系列密度西南桦Betula alnoides林分冠层光环境开展树冠遮阴试验,探究光环境对西南桦林木生长和枝条发育的影响,为合理配置造林密度进而实现西南桦优质大径材高效培育提供理论依据。
方法在系列造林密度试验基础上,以5年生、造林密度为4 m×4 m西南桦试验林的优势木和亚优势木为对象,设置3个遮阴梯度处理:遮阴率40%~45%、55%~60%和80%~90%,以无遮阴作对照(CK),依据西南桦物候期,于10月中上旬开始对下部2/3树冠进行遮阴处理,每隔3个月(或半年)调查参试单株的生长和枝条发育情况。
结果西南桦各处理间的树高和胸径在各调查时间段和整个试验期内的增量均差异不显著 (P≥0.05),胸径在1—4月份生长最快,各处理的胸径增量均超过0.73 cm。除2018年4—7月份期间枝条长度增量外,枝条发育在各时间段和整个试验期内均受遮阴显著影响(P<0.05),表现出随遮阴率的增加枝条直径、长度增量呈显著降低趋势,在生长旺季(1—4月份)差异更加明显,CK组的枝条直径和长度增量分别为遮阴率80%~90%处理的1.74和1.78倍,达到1.197 mm和0.135 m。此外,西南桦幼林自然整枝率亦表现出随遮阴率增加而明显增大的趋势,其自然整枝集中发生在4—7月份,整枝率增量均超过47%。
结论适宜的高造林密度形成的弱光环境对西南桦幼林单株生长影响较小,但是可以显著控制枝条发育,促进自然整枝。生产上适当提高西南桦造林密度有利于其优质大径级无节材的高效培育。
Abstract:ObjectiveA canopy shading experiment was conducted by simulating the light environments of plantations with a series of planting densities, to explore the effects of light environments on tree growth and branch development, and provide a theoretical guidance for the efficient cultivation of large-sized and high quality timber of Betula alnoides through reasonable arrangement of planting density.
MethodOn the basis of a series of afforestation density tests, three shading treatments (40%–45%, 55%–60% and 80%–90% shade rate) with 2/3 of the lower crown shaded and one control (CK) of no shade were set in plots with planting density of 4 m×4 m from a 5-year-old planting density trail of B. alnoides in early October following the local phenology of this species. The dominant tree and the subdominant tree were selected as experiment objects. The tree growth and branch development of all treated individuals were investigated every three or six months.
ResultThe increments of tree height and diameter at breast height (DBH) in each interval and the whole experimental period did not differ significantly among shading treatments (P≥0.05). DBH increment was the highest from January to April, and exceeded 0.73 cm in each treatment. However, branch development in each interval and the whole experimental period was significantly affected by shading (P<0.05), excepting branch length growth from April to July in 2018. Both the increments of branch diameter and length decreased significantly with the increase of shading rate, and the increasing trend was more significant in fast-growing season (from January to April), in which the increments of branch diameter and length of CK was 1.74 and 1.78 times higher than those of 80%–90% shade rate treatment, and reached 1.197 mm and 0.135 m, respectively. Moreover, the natural pruning rate ofB. alnoides young plantations also showed an obvious increasing trend with the increase of shading rate, and the natural pruning was focused from April to July with pruning rate increment over 47%.
ConclusionThe low light environment caused by appropriate high planting density almost has no significant effect on the individual growth of B. alnoides, while it can efficiently control branch development and promote natural pruning. The planting with an appropriate high density would be beneficial for large-sized and high quality timber cultivation of B. alnoides in practice.
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Keywords:
- Betula alnoides /
- light condition /
- individual tree growth /
- branch development /
- natural pruning
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表 1 不同遮阴率处理下参试植株的生长状况1)
Table 1 Growth performance of test individuals in different shading treatments
遮阴率/%
Shade rate树高/m
Tree height胸径/cm
DBH枝下高/m
Height below branch冠长/m
Crown length0(CK) 6.77±0.484 7.83±0.133 1.73±0.338 5.03±0.393 40~45 6.87±0.067 7.43±0.176 1.30±0.058 5.57±0.882 55~60 6.37±0.584 6.63±0.869 1.67±0.633 4.70±0.750 80~90 6.87±0.636 7.17±0.120 1.58±0.434 5.28±0.812 1) 表中数据为平均值±标准误(n=3)
1) The data in the table are means ± standard errors (n=3)表 2 不同遮阴率处理下西南桦幼林树高、胸径生长动态1)
Table 2 Growth dynamics of tree height and diameter at breast height for young Betula alnoides in different shading treatments
指标
Index遮阴率/%
Shade rate2017–10—2018–01 2018–01—04 2018–04—07 2018–07—2019–01 合计
Totalh/m 0(CK) 0.283±0.044a 0.417±0.060a 0.333±0.088a 0.400±0.115a 1.433±0.120a 40~45 0.167±0.089a 0.367±0.167a 0.900±0.100a 0.600±0.057a 2.033±0.145a 55~60 0.167±0.033a 0.567±0.203a 0.567±0.285a 0.533±0.089a 1.833±0.088a 80~90 0.400±0.039a 0.367±0.145a 0.300±0.115a 0.467±0.076a 1.533±0.145a DBH/cm 0(CK) 0.433±0.120a 0.733±0.133a 0.400±0.057a 0.967±0.120a 2.533±0.384a 40~45 0.367±0.145a 1.000±0.153a 0.100±0.033a 0.833±0.088a 2.300±0.252a 55~60 0.267±0.088a 0.833±0.120a 0.300±0.057a 0.800±0.115a 2.200±0.208a 80~90 0.133±0.067a 0.967±0.145a 0.400±0.020a 0.833±0.376a 2.333±0.561a 1) h:树高增量;DBH:胸径增量;表中数据为平均值±标准误(n=3);相同指标同列数据后的相同小写字母表示处理间差异不显著(P≥0.05,Duncan’s法)
1) h: Tree height increment; DBH: DBH increment; The data in the table are means ± standard errors (n=3); The same lowercase letters in the same column of the same index indicate no significant difference among treatments (P≥0.05,Duncan’s method)表 3 不同遮阴率处理下西南桦幼林枝条生长动态1)
Table 3 Branch growth dynamics of young Betula alnoides in different shading treatments
指标
Index遮阴率/%
Shade rate2017–10—2018–01 2018–01—04 2018–04—07 2018–07—2019–01 合计
Totald/mm 0(CK) 1.213±0.059a 1.197±0.056a 0.841±0.074a 1.429±0.072a 4.680±0.261a 40~45 1.123±0.062a 1.021±0.058b 0.846±0.094a 1.288±0.100ab 4.278±0.314b 55~60 0.805±0.061b 0.776±0.057c 0.661±0.120ab 1.109±0.127b 3.351±0.365c 80~90 0.753±0.061b 0.687±0.057c 0.552±0.111b 0.708±0.116c 2.700±0.345d l/m 0(CK) 0.118±0.008a 0.135±0.009a 0.086±0.008a 0.135±0.009a 0.474±0.034a 40~45 0.081±0.008b 0.136±0.009a 0.081±0.010a 0.132±0.013a 0.430±0.040a 55~60 0.072±0.008b 0.090±0.009b 0.067±0.012a 0.107±0.016ab 0.336±0.045b 80~90 0.070±0.008b 0.076±0.009b 0.065±0.012a 0.075±0.015b 0.286±0.044b 1) d:枝条直径增量;l:枝条长度增量;表中数据为平均值±标准误(n=3);相同指标同列数据后的不同小写字母表示处理间差异显著(P<0.05,Duncan’s法)
1) d: Branch diameter increment; l: Branch length increment; The data in the table are means ± standard errors (n=3); Different lowercase letters in the same column of the same index indicate significant differences among treatments (P<0.05, Duncan’s method)表 4 不同遮阴处理下西南桦幼林自然整枝率1)
Table 4 Natural pruning rate of young Betula alnoides in different shading treatment
% 遮阴率/% Shade rate 2018–01 2018–04 2018–07 2019–01 0(CK) 2.020±2.020a 5.374±3.566a 37.778±2.222b 38.788±1.212b 40~45 19.341±4.847a 21.397±5.517a 68.661±5.144a 74.359±4.933a 55~60 8.530±5.279a 11.235±5.852a 77.982±10.029a 81.598±7.967a 80~90 18.046±9.194a 21.233±8.926a 77.674±7.792a 81.297±8.033a 1) 表中数据为平均值±标准误(n=3);同列数据后的不同小写字母表示处理间差异显著(P<0.05,Duncan’s法)
1) The data in the table are means ± standard errors (n=3); different lowercase letters in the same column indicate significant differences among treatments (P<0.05, Duncan’s method) -
[1] 蔡志全, 曹坤芳, 冯玉龙, 等. 热带雨林三种树苗叶片光合机构对光强的适应[J]. 应用生态学报, 2003(4): 493-496. doi: 10.3321/j.issn:1001-9332.2003.04.003 [2] 李晓征, 郝日明, 任燕. 遮荫处理对不同苗龄交让木的生长和光合特性的影响[J]. 广西植物, 2006(5): 499-502. doi: 10.3969/j.issn.1000-3142.2006.05.008 [3] 徐飞, 郭卫华, 徐伟红, 等. 不同光环境对麻栎和刺槐幼苗生长和光合特征的影响[J]. 生态学报, 2010, 30(12): 3098-3107. [4] 方江保, 殷秀敏, 余树全, 等. 光照强度对苦槠幼苗生长与光合作用的影响[J]. 浙江林学院学报, 2010, 27(4): 538-544. [5] 王博轶, 冯玉龙. 生长环境光强对两种热带雨林树种幼苗光合作用的影响[J]. 生态学报, 2005, 25(1): 23-30. doi: 10.3321/j.issn:1000-0933.2005.01.005 [6] 姜英, 郝海坤, 黄志玲, 等. 红锥苗期生长特性和叶绿素荧光对不同光强的响应[J]. 中南林业科技大学学报, 2013, 33(10): 61-65. doi: 10.3969/j.issn.1673-923X.2013.10.014 [7] 陈香波, 田旗, 张丽萍, 等. 不同透光率和土壤含水量对夏蜡梅枝条生长量及叶片部分生理指标的影响[J]. 植物资源与环境学报, 2010, 19(4): 70-77. doi: 10.3969/j.issn.1674-7895.2010.04.011 [8] 梁俊林, 毛绘友, 郭丽, 等. 遮阴对3种珍贵乡土阔叶树种幼苗生长及光合作用的影响[J]. 西北林学院学报, 2019, 34(4): 57-63. doi: 10.3969/j.issn.1001-7461.2019.04.08 [9] 段如雁, 韦小丽, 孟宪帅. 不同光照条件下花榈木幼苗的生理生化响应及生长效应[J]. 中南林业科技大学学报, 2013, 33(5): 30-34. [10] 周凤娇, 韦小丽, 彭凌帅, 等. 遮荫处理对马尾松穗条产量和生理生化特性的影响[J]. 中南林业科技大学学报, 2018, 38(4): 16-19. [11] 王树凤, 施翔, 陈益泰, 等. 遮荫对弗吉尼亚栎苗木生长及光合−荧光参数的影响[J]. 林业科学研究, 2019, 32(5): 99-106. [12] MÄKINEN H. Effect of stand density on the branch development of silver birch (Betula pendula Roth) in central Finland[J]. Trees, 2002, 16(4): 346-353. doi: 10.1007/s00468-002-0162-x
[13] ULVCRONA K A, CLAESSON S, SAHLEN K, et al. The effects of timing of pre-commercial thinning and stand density on stem form and branch characteristics of Pinus sylvestris[J]. Forestry, 2007, 80(3): 323-335. doi: 10.1093/forestry/cpm011
[14] 王志海, 尹光天, 杨锦昌, 等. 不同造林密度对米老排人工林枝条发育的影响[J]. 林业科学研究, 2019, 32(2): 78-86. [15] DONG T, LI J Y, ZHANG Y B, et al. Partial shading of lateral branches affects growth, and foliage nitrogen-and water-use efficiencies in the conifer Cunninghamia lanceolata growing in a warm monsoon climate[J]. Tree Physiology, 2015, 35(6): 632-643. doi: 10.1093/treephys/tpv036
[16] 曾杰, 郭文福, 赵志刚, 等. 我国西南桦研究的回顾与展望[J]. 林业科学研究, 2006, 19(3): 379-384. doi: 10.3321/j.issn:1001-1498.2006.03.022 [17] 王春胜, 唐诚, 赵志刚, 等. 桂西地区西南桦中龄林生长对间伐和施肥的响应[J]. 中南林业科技大学学报, 2018, 38(5): 28-32. [18] WANG C S, HEIN S, ZHAO Z G, et al. Branch occlusion and discoloration of Betula alnoides under artificial and natural pruning[J]. Forest Ecology and Management, 2016, 375: 200-210. doi: 10.1016/j.foreco.2016.05.027
[19] WANG C S, TANG C, HEIN S, et al. Branch development of five-year-old Betula alnoides plantations in response to planting density[J]. Forests, 2018, 9: 42. doi: 10.3390/f9010042
[20] 骆丹, 王春胜, 曾杰. 西南桦幼林冠层光合特征及其对造林密度的响应[J]. 中南林业科技大学学报, 2020, 40(4): 44-49. [21] 王振兴, 朱锦懋, 王健, 等. 闽楠幼树光合特性及生物量分配对光环境的响应[J]. 生态学报, 2012, 32(12): 3841-3848. [22] 郑坚, 吴朝辉, 陈秋夏, 等. 遮荫对降香黄檀幼苗生长和生理的影响[J]. 林业科学, 2016, 52(12): 50-57. doi: 10.11707/j.1001-7488.20161206 [23] WANG C S, GUO J J, HEIN S, et al. Foliage morphology and spatial distribution in 5-year-old plantations of Betula alnoides[J]. Forest Ecology and Management, 2019, 432: 514-521. doi: 10.1016/j.foreco.2018.09.052
[24] MORI A S, MIZUMACHI E, SPRUGEL D G. Morphological acclimation to understory environments in Abies amabilis, a shade-and snow-tolerant conifer species of the Cascade Mountains, Washington, USA[J]. Tree Physiology, 2008, 28(5): 815-824. doi: 10.1093/treephys/28.5.815
[25] 熊静, 王臣, 邢文黎, 等. 朱砂根幼苗在不同光照强度下的形态和生理响应[J]. 植物科学学报, 2018, 36(5): 736-744. doi: 10.11913/PSJ.2095-0837.2018.50736 [26] 郝建, 李武志, 陈厚荣, 等. 人工整枝技术在用材林培育中的应用[J]. 林业科技开发, 2012, 26(5): 9-12. doi: 10.3969/j.issn.1000-8101.2012.05.002 [27] 陈东升, 孙晓梅, 李凤日, 等. 落叶松人工林节子内部特征变化规律研究[J]. 北京林业大学学报, 2015, 37(2): 16-23. [28] 占峰, 杨冬梅. 光照条件、植株冠层结构和枝条寿命的关系:以桂花和水杉为例[J]. 生态学报, 2012, 32(3): 984-992. [29] 陶玉华, 赵峰, 庞正轰, 等. 西南桦人工林生长规律研究[J]. 西北林学院学报, 2019, 34(1): 180-183. doi: 10.3969/j.issn.1001-7461.2019.01.27 -
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