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地形作为植被格局和资源利用的代表,在森林生态系统中扮演着极其重要的角色[1-2],是多数植被得以在森林群落中稳定共存的重要因素[3]。地形是一个多维因素,包括坡向、坡度、坡位和海拔等生态因子,每一维对光、温度、水以及土壤养分的影响各有侧重。坡向影响辐射强度和日照时数,使不同坡向的光照、温度和水分条件有较大的差异[4];坡度则影响太阳的投射角度,使可获得的太阳辐射不同,土壤理化性质、气温等生态因子将随之发生变化[5];坡位不同,则土壤水分和养分也不相同[6];海拔高度不同,则温度、降水量、土壤条件均有不同[7]。通常水分充足时,树木的生长在阳坡优于阴坡,而水分不足时则相反,喜湿树木适宜在坡度较小和坡的下部生长,耐旱树木适宜在坡度较大和坡的上部生长[8],海拔对不同树种树木胸径生长的影响也存在差异[9-10]。由于这些生态因子的多种配合,使山地的生境变得复杂,也使同种个体处于不同的生长条件下,表现出树木生长率的差异,而生长率的差异可能主要源于森林中不同树木生长对地形响应的不确定性。因此,在群落尺度的植被研究中,地形因子的作用已引起国内外学者的广泛关注。
在生态系统中,树木的胸径生长率通常与树木的存活率呈正相关,而与死亡率呈负相关[11-13],表明在植物种群生态学和群落生态学研究中树木生长机制是一个核心问题[14-16]。地形是决定树木生长发育的重要因素[17],已有研究表明:坡向影响大树胸径的相对生长率;坡位影响幼树胸径的相对生长率[18]。相对于山谷、下坡和上坡,位于山脊处的幼树一般生长缓慢[19],主要源于缺少可利用的矿质营养或者在某一时间段水分短缺[20-22],并且由于山脊处风速较高,树木易受到破坏[23]。
除地形外,树木之间的竞争也是影响树木生长的限制因素,尤其是在混交林中,竞争能力不仅代表了树木生长发育状况,还与其对周围资源的占有及利用存在联系[24-25]。在石栎(Lthocarpus glaber)-青冈(Cyclobalanopsis glauca)混交林中,林木胸径小于8 cm时,树木竞争压力显著下降,当其超过8 cm时,竞争压力无显著变化[24]。以往研究还表明树木生长受到周围树木的显著影响,周围树木胸径越小、数量越少,树木胸径的生长越快,即树木胸径生长受邻体大小和密度制约[26]。树木胸径生长还与其周围树木的距离具有很高的相关性,即树木胸径生长受邻体距离制约[27-28],树木之间的竞争会减缓树木胸径的生长,对树木个体的发育造成差异[29]。此外,竞争对不同径级树木的胸径生长也会造成显著差异,光照的竞争主要影响小径级树木的胸径生长,而土壤养分的竞争影响所有树木的胸径生长[28]。
阔叶红松(Pinus koraiensis)林是我国东北东部山区的地带性顶极植被群落,同时也是北方森林的重要组成部分,该区气候寒冷,季节变化鲜明,土壤潮湿,属于全球气候变化敏感区域。近年来,地形对阔叶红松林植物生长影响的研究逐渐开展,但目前多集中于地形对阔叶红松林幼苗及灌木更新影响的研究[30-31]。关于地形对阔叶红松林主要乔木胸径生长影响的研究尚少,而且现为数不多的对阔叶红松林的研究也没有考虑对径级的划分和林木竞争的影响。本研究旨在探索树木在不同地形和竞争压力下对不同径级以及不同耐荫性树木胸径生长的影响,研究结果可为预测树木胸径的生长以及种群的发展趋势奠定基础,为深入了解原始林生态系统结构与功能提供科学依据。
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实验样地位于黑龙江凉水国家级自然保护区(49°10′50″N、128°57′20″E),地处小兴安岭南坡达里带岭支脉东坡。地形比较复杂,海拔280~707 m,地带性土壤为暗棕壤。境内密被森林,属大陆性季风气候,年平均气温-0.3 ℃,年平均降水量676 mm。地带性植被是以红松为建群种的温带针阔叶混交林,伴生乔木主要包括冷杉(Abies nephrolepis)、紫椴(Tilia amurensis)、色木槭(Acer mono)、枫桦(Betula costata)、水曲柳(Fraxinus mandshurica)、花楷槭(Acer ukurunduense)、青楷槭(A. tegmentosum)、裂叶榆(Ulmus laciniata)、春榆(U. japonica)等。伴生灌木主要包括刺五加(Acanthopanax senticosus)、毛榛子(Corylus mandshurica)、瘤枝卫矛(Euonymus pauciflorus)、黄花忍冬(Lonicera chrysantha)、东北山梅花(Philadelphus schrenkii)等。藤本植物主要为狗枣猕猴桃(Actinidia kolomikta)。
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2005年在黑龙江凉水国家级自然保护区建立了典型阔叶红松林动态监测样地,样地面积为300 m×300 m,将样地划分成900个10 m×10 m的样方,采用相邻网格法对样地内所有DBH≥1 cm的树木鉴别种类、测量胸径、确定坐标、悬挂树牌,并于2010年和2015年分别进行复查。样地内木本植物共48种,隶属于20科34属。最高海拔508 m,最低海拔425 m,地势较为平缓。
将每个10 m×10 m的样方划分成4个5 m×5 m的小样方,调查每个小样方的坡向、坡度、坡位。其中坡向分为阴坡(337.5°~22.5°和22.5°~67.5°)、半阴坡(67.5°~112.5°和292.5°~337.5°)、平地、半阳坡(112.5°~157.5°和247.5°~292.5°)和阳坡(157.5°~247.5°)。根据坡面的倾斜程度,将坡度分为<6°、6°~15°、16°~25°和>25°共4个等级;根据山坡的不同部位,将坡位分为谷地、下坡、上坡和山脊[32]。
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胸径年均生长量指树木每年胸径的平均增长量,可利用下式得到:
$$ Z = ({D_n} - {D_{n - t}}/t) $$ (1) 式中:Z为胸径年均生长量,Dn为第n年树木的胸径,t为两次调查时期的间隔年数。本研究中n为2015,t为5年。
根据2010年样地内的调查数据,计算样地内每株树木的竞争指数。选取任意树木作为对象木,以该对象木为圆心,以半径6 m为圆,落在定义圆内的所有树木作为竞争木[33]。为避免边缘效应,凡是处于样地边缘的树木不能作为对象木,只可作为竞争木,本研究将所有处于样地边缘10 m×10 m的样方作为缓冲区。
采用Hegyi的单木竞争指数(Competition index, CI)[34]量化林木之间的竞争压力,计算公式为:
$$ {\text{CI = }}\sum\limits_{j = 1}^N {({D_j}/{D_i})\frac{1}{{{d_{ij}}}}} $$ (2) 式中:Di和Dj分别表示对象木i和竞争木j的胸径,dij表示对象木i和竞争木j之间的距离,N为落在定义圆内的株数。CI值越大,表明来自周围竞争木的竞争压力越强,即树木之间的竞争越激烈,在竞争中处于不利的地位。
根据样地内树种的重要值大小,选取8个主要乔木树种[35],依据胸径大小将其分成2个径级,包括径级Ⅰ(1 cm≤DBH<10 cm)和径级Ⅱ(DBH≥10 cm)[36],计算其胸径年均生长量。整体上,将样地内所有树木分成耐荫树种组和非耐荫树种组两种生活习性[37],并分成径级Ⅰ和径级Ⅱ,计算其胸径年均生长量。利用回归分析阐明不同树种胸径与年均胸径生长量的关系;利用单因素方差分析(one-way ANOVA)分别探讨地形和竞争对阔叶红松林树木胸径年均生长量的影响,利用LSD检验进行多重比较。竞争指数计算利用C#语言编程实现,统计分析采用SPSS 19.0软件,绘图采用Origin Pro 2015软件。
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阔叶红松林主要组成树种的胸径年均生长量与其胸径大小均呈极显著相关(P<0.001),其中红松、紫椴、色木槭、水曲柳、枫桦、春榆、青楷槭的胸径年均生长量均随胸径的增大呈先增高再降低的趋势,而冷杉的胸径年均生长量随胸径的增大而增高(图 1)。
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红松、紫椴和色木槭径级Ⅱ(DBH≥10 cm)在平地、<6°的坡度等级、谷地上的胸径年均生长量均显著高于其他相应地形(P<0.05);紫椴和色木槭径级Ⅰ(1 cm≤DBH<10 cm)在阳坡、>25°的坡度等级、山脊上的胸径年均生长量均显著高于其他相应地形(P<0.05);水曲柳径级Ⅱ在阴坡的年均胸径生长量显著高于其他坡向(P<0.05);冷杉径级Ⅰ在山谷的胸径年均生长量显著高于其他坡位(P<0.05)(表 1)。相对而言,地形对枫桦、春榆和青楷槭的胸径年均生长量均没有显著影响(表 1)。
表 1 地形对阔叶红松林主要组成树种年均胸径生长量的影响
Table 1. Influence of topography on annual average DBH increment of major tree species in a mixed broadleaved-Korean pine forest
mm·a-1 mm·year-1 地形
Topography红松Pinus koraiensis 紫椴Tilia amurensis 色木槭Acer mono 水曲柳Fraxinus mandshurica Ⅰ Ⅱ Ⅰ Ⅱ Ⅰ Ⅱ Ⅰ Ⅱ 坡向
Slope aspect平地Flat 1.10±0.18 2.51±0.18a 0.85±0.22b 5.38±1.77a 0.73±0.07b 2.86±0.16a 1.27±0.36 2.76±0.42b 阴坡Shady slope 2.01±0.08b 0.80±0.20b 0.85±0.27b 2.22±0.09b 5.80±2.53a 半阴坡Semi-shady slope 0.73±0.15 1.76±0.12b 0.88±0.16b 2.09±0.49b 0.81±0.10b 2.19±0.18b 1.60±1.08 1.94±0.31b 半阳坡Semi-sunny slope 0.75±0.24 1.90±0.10b 1.03±0.12b 2.09±0.28b 0.89±0.11b 2.19±0.07b 0.94±0.24 2.69±0.33b 阳坡Sunny slope 0.52±0.15 2.04±0.10b 2.61±0.16a 2.38±0.32b 1.33±0.07a 2.26±0.07b 1.40±0.22 2.34±0.26b 坡度
Slope gradient<6° 1.04±0.18 2.38±0.15a 0.94±0.18b 4.73±0.18a 0.85±0.11b 2.74±0.13a 1.18±0.27 2.66±0.34 6°~15° 0.75±0.19 1.92±0.09b 1.00±0.12b 2.24±0.23b 0.81±0.05b 2.19±0.05b 1.57±0.28 2.50±0.25 15°~25° 0.70±0.20 1.99±0.11b 0.94±0.16b 2.28±0.40b 0.89±0.10b 2.32±0.15b 0.50±0.11 2.49±0.34 >25° 0.25±0.15 1.72±0.18b 2.64±1.65a 2.73±0.34b 1.25±0.16a 2.12±0.16b 1.87±0.62 2.13±0.52 坡位
Slopeposition山谷Valley 1.04±0.18 2.45±0.18a 1.12±0.27b 2.01±1.47a 0.75±0.07b 2.85±0.15a 1.22±0.29 2.69±0.35 下坡Lower slope 0.71±0.15 1.92±0.09b 1.06±0.10b 2.16±0.25b 0.73±0.05b 2.23±0.07b 1.19±0.21 2.38±0.21 上坡Upper slope 0.64±0.23 2.07±0.11b 0.87±0.11b 2.22±0.35b 0.75±0.06b 2.15±0.07b 1.68±0.53 2.80±0.46 山脊Ridge 1.80±0.04b 2.47±0.10a 2.10±0.30b 1.37±0.59a 2.11±0.06b 1.40±1.11 地形
Topography冷杉Abies nephrolepis 枫桦Betula costata 春榆Ulmus japonica 青楷槭Acer tegmentosum Ⅰ Ⅱ Ⅰ Ⅱ Ⅰ Ⅱ Ⅰ Ⅱ 坡向
Slope aspect平地Flat 1.45±0.27 2.57±0.26 0.61±0.12 2.74±0.42 1.36±0.26 2.76±1.13 1.91±0.24 2.89±0.80 阴坡Shady slope 1.25±0.47 2.32±0.44 0.57±0.07 1.70±0.90 1.24±0.39 半阴坡Semi-shady slope 1.06±0.20 2.20±0.23 0.31±0.07 2.46±0.24 1.40±0.20 4.00±2.20 2.20±0.19 1.45±0.26 半阳坡Semi-sunny slope 0.80±0.12 2.10±0.14 0.57±0.10 2.94±0.37 1.42±0.25 3.67±0.95 1.83±0.12 2.17±0.37 阳坡Sunny slope 1.16±0.13 2.31±0.16 0.55±0.08 2.87±0.29 1.00±0.12 3.84±0.88 1.92±0.21 2.32±0.39 坡度Slope gradient <6° 1.45±0.22 2.67±0.28 0.62±0.11 2.93±0.33 1.43±0.23 3.43±0.74 1.92±0.18 2.92±0.66 6°~15° 1.01±0.11 2.20±0.11 0.46±0.07 2.70±0.25 0.94±0.15 3.12±0.64 1.86±0.11 2.36±0.34 15°~25° 0.82±0.13 2.13±0.17 0.56±0.10 2.68±0.33 1.21±0.20 3.33±0.72 2.12±0.20 1.64±0.20 >25° 1.14±0.19 2.23±0.36 0.20±0.09 2.55±0.56 1.28±0.29 1.92±0.53 1.74±0.97 坡位Slope position 山谷Valley 1.58±0.25a 2.54±0.25 0.60±0.12 2.99±0.41 1.31±0.22 4.03±1.57 1.94±0.22 2.89±0.80 下坡Lower slope 0.96±0.10b 2.32±0.12 0.51±0.07 2.76±0.22 1.22±0.14 3.80±0.60 1.91±0.10 2.07±0.28 上坡Upper slope 1.03±0.13b 1.98±0.14 0.48±0.08 2.68±0.33 0.93±0.27 2.44±1.22 2.01±0.23 2.16±0.41 山脊Ridge 2.72±1.06 0.48±0.08 2.55±0.56 0.87±0.77 注:Ⅰ表示1 cm≤DBH<10 cm,Ⅱ表示DBH≥10 cm;表中数值为平均值±标准误;不同小写字母表示不同地形下差异显著(P<0.05)。Notes:Ⅰ, 1 cm≤DBH<10 cm; Ⅱ, DBH≥10 cm; Data in table is mean±SE; Different minuscules represent significant difference at P<0.05 level on different topography conditions. -
整体来看,地形对阔叶红松林中耐荫树种组径级Ⅰ和非耐荫树种组径级Ⅱ的胸径年均生长量均具有显著影响(P<0.05)。耐荫树种组径级Ⅰ在平地上的胸径年均生长量显著低于其他坡向(P<0.05),在>25°的坡度等级、山脊上的胸径年均生长量显著高于相应的其他地形;非耐荫树种组径级Ⅱ在平地、<6°的坡度等级、谷地上的胸径年均生长量显著高于相应的其他地形。相对而言,地形对阔叶红松林中耐荫树种组径级Ⅱ和非耐荫树种组径级Ⅰ的胸径年均生长量均无显著影响(图 2)。
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整体来看,地形对阔叶红松林径级Ⅱ树木的胸径年均生长量具有显著影响(P<0.05),其在平地、<6°的坡度等级和谷地的胸径年均生长量显著高于其他相应的地形;而地形对径级Ⅰ树木的胸径年均生长量无显著影响(图 3)。
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竞争压力对阔叶红松林主要组成树种(春榆除外)径级Ⅰ的胸径年均生长量均具有显著影响(P<0.05),对红松、紫椴、色木槭、冷杉和春榆径级Ⅱ的胸径年均生长量也存在显著影响,且随着竞争指数等级的增加,其胸径年均生长量均呈显著降低的趋势。竞争指数较小时(CI<5),其胸径年均生长量均显著高于其他竞争指数等级(表 2)。
表 2 竞争对阔叶红松林主要组成树种年均胸径生长量的影响
Table 2. Influence of competition on annual average DBH increment of major tree species in a mixed broadleaved-Korean pine forest
mm·a-1 mm·year-1 竞争指数Competition index(CI) 红松Pinus koraiensis 紫椴Tilia amurensis 色木槭Acer mono 水曲柳Fraxinus mandshurica Ⅰ Ⅱ Ⅰ Ⅱ Ⅰ Ⅱ Ⅰ Ⅱ <5 2.34±0.06a 2.12±0.07a 1.87±0.13a 2.91±0.39a 1.36±0.06a 2.46±0.13a 2.38±0.69a 2.56±0.18 5~10 0.88±0.14b 1.47±0.13b 1.09±0.13b 1.69±0.26b 1.11±0.08b 1.44±0.15b 1.39±0.22b 1.40±0.55 >10 0.98±0.15b 1.71±0.25b 0.99±0.08b 1.60±0.10b 0.81±0.43c 1.11±0.42b 0.86±0.18b 竞争指数Competition index(CI) 冷杉Abies nephrolepis 枫桦Betula costata 春榆Ulmus japonica 青楷槭Acer tegmentosum Ⅰ Ⅱ Ⅰ Ⅱ Ⅰ Ⅱ Ⅰ Ⅱ <5 2.03±0.07a 2.38±0.10a 1.92±0.16a 2.80±0.17 1.25±0.34 2.59±0.37a 3.09±0.42a 2.38±0.26 5~10 1.11±0.08b 1.50±0.16b 1.05±0.10b 2.13±0.71 1.28±0.16 1.31±0.14b 2.24±0.25b 2.16±0.22 >10 1.01±0.11b 1.43±0.39b 0.60±0.08c 1.23±0.18 1.08±0.12b 1.79±0.09c 2.08±0.20 注:Ⅰ表示1 cm≤DBH<10 cm,Ⅱ表示DBH≥10 cm;不同小写字母表示不同竞争指数等级下差异显著(P<0.05)。Notes:Ⅰ, 1 cm≤DBH<10 cm; Ⅱ, DBH≥10 cm; Different minuscules represent significant difference at P<0.05 level under different competition index grades. -
竞争压力对耐荫树种组和非耐荫树种组的胸径年均生长量均具有显著影响(P<0.05)。随着竞争指数等级的增加,耐荫树种组以及非耐荫树种组胸径年均生长量均呈显著降低的趋势,耐荫树种组的年均胸径生长量在CI为5~10和CI>10时分别小于CI<5时的41.3%和54.1%,而非耐荫树种组的年均胸径生长量在CI为5~10和CI>10时分别小于CI<5时的37.2%和50.5%。各竞争指数等级中耐荫树种组胸径年均生长量均显著低于非耐荫树种组,随着竞争指数等级的增加其降低比例越来越高,分别为10.1%、16.1%和16.7%(图 4)。
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竞争压力对径级Ⅰ和径级Ⅱ树木的胸径年均生长量均具有显著影响(P<0.05)。随着竞争指数等级的增大,径级Ⅰ树木的胸径年均生长量显著降低,而径级Ⅱ树木在CI<5时的胸径年均生长量显著高于其他竞争指数等级(图 5)。
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生境过滤对树木的生长至关重要,而地形因子是生境过滤的主要驱动因子之一[38]。本研究结果表明,地形对阔叶红松林主要组成树种的胸径年均生长量有显著影响,说明地形是研究区域内森林生态系统中一个重要的影响因素,这与现有的地形对长白山区天然核桃楸(Juglans mandshurica)胸径生长影响的研究结果类似[39]。红松、紫椴、色木槭均为非耐荫树种,且其大径级树木喜湿润,从阴坡到阳坡光照强度依次增强,而水分依次减少;坡度越大则水分的流失越严重,土壤受侵蚀的可能性也越大;从谷地到山脊土壤含水量和养分不断下降[40-42],因此,大径级的红松、紫椴、色木槭更适合在平地、缓坡、山谷上生长。小径级的紫椴与色木槭生长需要更多的光照,则更适合在阳坡、陡坡、山脊上生长,但是小径级的红松胸径年均生长量不受地形的影响,可能源于小径级红松耐庇荫,可以在较阴暗的环境条件下生长。这说明不仅不同树种在相同的环境条件下其生长会表现出有所差异[43],而且同一树种在不同的生长阶段对环境的响应也不同,甚至相反[44]。水曲柳为非耐荫树种,但其大径级树木却适合在阴坡生长,可能因为林中大径级水曲柳已经在获取光的竞争中占据优势,所以随着树木年龄的增长,水分可能是限制其生长的主要因子。冷杉是耐荫树种并且喜湿润,所以其小径级树木适合在水分较多的谷地上生长。
树种的耐荫性是指树种能在弱光下继续生存的能力,尤其是幼树的耐荫性是造林学上的一个重要问题。耐荫与非耐荫植物在叶片厚度、叶面积、比叶面积等植物功能性状上均有所差异[45],因此耐荫和非耐荫植物对地形表现出了不同的响应。耐荫树种组不需要较强的光照也能生长,而非耐荫树种组的生长需要更多的光照。具体来说,大径级的非耐荫树种组胸径的生长需要较强的光照以及较多的水分,因此大径级的非耐荫树种组在平地、缓坡、谷地上的胸径年均生长量更高,而小径级的耐荫树种组胸径的生长不需要较强光照和水分,则呈现出与大径级的非耐荫树种组相反的结果(图 2)。这说明以资源生态位分化的环境特殊性为依据,不同物种适应不同环境,即保持了相对高的物种丰富度和多样性[46]。
总体而言,地形对小径级树木的胸径年均生长量影响不显著,而对大径级树木的胸径年均生长量影响显著(图 3)。这与热带森林中大径级比小径级树木在生长和周围环境之间有更大联系的观点类似[18]。由于大径级树木已经经历了生境过滤的过程,淘汰的个体可能曾经在这一地形上萌芽,但是它们并不适合这一立地条件[47-49]。大径级的树木在平地、<6°的坡度等级、谷地上胸径年均生长量更高(图 3),说明从小径级成长为大径级树木,控制树木生长的主要限制因子就由光照逐渐转变为水分[44],这个过程类似于生境对个体的平稳选择,大径级相比于小径级树木对水分的需求更多,因此可为我们提供地形对不同径级树木胸径生长的调节机理,为科学管理阔叶红松林提供理论依据。
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生物互作是物种共存与生物多样性维持的另一重要机制,而竞争是生物互作的主要形式,一般作用于植物的早期生活史阶段[50]。本研究结果表明,竞争对阔叶红松林中除春榆外的7种主要组成树种径级Ⅰ的胸径生长均起到抑制作用,这可能源于春榆新增数量较多且呈聚集分布,这更有利于自身的保护和生长发育。但是,竞争对红松、紫椴、色木槭、冷杉、春榆径级Ⅱ的胸径生长产生抑制作用,可能是由于这些树种均为喜湿润的植物,在林中缓坡和谷地上分布的数量较多,导致对水分的竞争更激烈,进而抑制胸径生长。
植物的生长多取决于自身个体的大小[51]。如亚热带常绿阔叶植物红楠(Machilus thunbergii)[52],其树高生长与自身大小表现出正相关幂函数关系。除冷杉的胸径年均生长量与其胸径大小表现为线性关系外,其他7个树种的关系均表现为二次函数关系,说明树木的生长会随着生长发育阶段的变化而变化。竞争压力对小径级树木和大径级树木的胸径年均生长量均具有显著影响,这与对新西兰山毛榉(Fagus longipetiolata)[28]的研究结果类似。当CI<5时,小径级树木和大径级树木的胸径年均生长量均最高;当CI≥5时,竞争压力对大径级树木的胸径生长影响不显著,而小径级树木的胸径生长依然受竞争压力的抑制。这说明相比于大径级树木,竞争对小径级树木的生长具有主导作用,可能主要源于小径级树木上层有大径级树木分布,大径级树木在获取光照的竞争中占优势地位,即非对称竞争,而小径级树木对获取光的竞争会更加激烈,光照对树木的生长至关重要[53-55],导致竞争抑制小径级树木的胸径生长。
树木耐荫性不同导致其年均胸径生长量降低的程度远小于因竞争指数等级不同而导致其胸径年均增长量降低的程度(图 5),说明相比于生活习性,竞争更能限制树木的生长[56]。由于耐荫树种组与非耐荫树种组的区别主要体现在地上资源-光的竞争,而引进的竞争指数不仅包括地上资源的竞争,还包括地下资源的竞争。有关水曲柳的研究表明:地上竞争对总竞争的直接作用范围(0.285 1~0.528 2)明显低于地下竞争对总竞争的直接作用范围(0.554 3~0.742 6);虽然随着聚集程度的下降,地下竞争作用减弱,地上竞争增加,但是地下竞争依然占主导地位[57]。
树木的生长受光照、水分、土壤等直接因子以及地形、竞争作用等间接因子的影响。本文着重分析了地形和竞争对典型阔叶红松林主要树种胸径生长的影响,而有关树木的生长对各生态因子以及种内和种间竞争的响应有待于长期监测和研究。
Influences of topography and competition on DBH growth in different growth stages in a typical mixed broadleaved-Korean pine forest, northeastern China
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摘要: 近年来,地形和竞争对树木生长影响机制的研究备受关注。本文基于黑龙江凉水国家级自然保护区内9 hm2典型阔叶红松林动态监测样地,使用2010年和2015年的野外调查数据,分析了地形(坡向、坡度、坡位)和树木间竞争对阔叶红松林主要组成树种胸径生长的影响。结果表明:紫椴、色木槭、冷杉径级Ⅰ(1 cm≤DBH<10 cm)以及红松、紫椴、色木槭、水曲柳径级Ⅱ(DBH≥10 cm)的胸径年均生长量与地形显著相关(P<0.05);竞争对红松、紫椴、色木槭、水曲柳、冷杉、枫桦、青楷槭径级Ⅰ以及红松、紫椴、色木槭、冷杉、春榆径级Ⅱ的胸径年均生长量有显著影响(P<0.05)。总体上,阔叶红松林中耐荫和非耐荫树种组的胸径年均生长量均受地形和竞争的显著影响;阔叶红松林中大径级树木的胸径生长主要受地形影响,而小径级树木的胸径生长主要受竞争影响。Abstract: In recent years, the influencing mechanism of topography and competition on tree growth is getting more attentions. The research was conducted in a 9 ha dynamic monitoring plot of typical mixed broadleaved-Korean pine (Pinus koraiensis) forest in Liangshui Natural Reserve, Heilongjiang Province of northeastern China. Based on field investigation data in 2010 and 2015, this study analyzes the influences of topography (i.e., slope aspect, slope gradient, slope position) and competition among trees on the increment of diameter at breast height (DBH) for major tree species in mixed broadleaved-Korean pine forest. Results showed that the annual average DBH increment of diameter classⅠ(1 cm≤DBH < 10 cm) for Tilia amurensis, Acer mono and Abies nephrolepis as well as diameter class Ⅱ(DBH≥10 cm) for Pinus koraiensis, Tilia amurensis, Acer mono, Fraxinus mandshurica were all significantly correlated with topography (P < 0.05). The competition had significant influences on the annual average DBH increment of Pinus koraiensis, Tilia amurensis, Acer mono, Fraxinus mandshurica, Abies nephrolepis, Betula costata, Acer tegmentosum for diameter class Ⅰ as well as diameter class Ⅱ for Pinus koraiensis, Tilia amurensis, Acer mono, Abies nephrolepis, Ulmus japonica (P < 0.05). Generally, the annual average DBH increment of shade-tolerant and non shade-tolerant groups was significantly influenced by both topography and competition in mixed broadleaved-Korean pine forest. The DBH increment of large diameter classes of trees was mainly influenced by the topography, while the DBH increment of small diameter classes of trees was mainly influenced by the competition.
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图 2 地形对阔叶红松林不同生活习性树木胸径年均生长量的影响
不同大写字母表示不同地形对径级Ⅰ树木胸径年均生长量的影响差异显著(P<0.05),不同小写字母表示不同地形对径级Ⅱ树木胸径年均生长量的影响差异显著(P<0.05)。图 3同此。
Figure 2. Influence of topography on annual average DBH increment of different living habits of trees in a mixed broadleaved-Korean pine forest
Different majuscules represent significant differences of diameter classⅠ's annual average DBH increment at P < 0.05 level on different topography. Different minuscules represent the significant difference of diameter class Ⅱ's annual average DBH increment at P < 0.05 level on different topography. Same as Fig. 3.
图 4 竞争压力对耐荫树种组和非耐荫树种组胸径年均生长量的影响
不同大写字母表示不同竞争压力对耐荫树种组和非耐荫树种组胸径年均生长量的影响差异显著(P<0.05),不同小写字母表示各竞争指数等级中耐荫树种组和非耐荫树种组胸径年均生长量的影响差异显著(P<0.05)。
Figure 4. Influence of competition on annual average DBH increment of shade-tolerant and non shade-tolerant groups in a mixed broadleaved-Korean pine forest
Different majuscules represent the significant difference of annual average DBH increment of shade-tolerant and non-shade groups at P < 0.05 level under different competitive pressures. Different minuscules represent the significant difference of annual average DBH increment of different shade-tolerant groups at P < 0.05 level under same competitive pressures.
图 5 竞争压力对阔叶红松林不同径级树木胸径年均生长量的影响
不同大写字母表示竞争压力对径级Ⅰ树木胸径年均生长量的影响差异显著(P<0.05),不同小写字母表示竞争压力对径级Ⅱ树木胸径年均生长量的影响差异显著(P<0.05)。
Figure 5. Influence of competition on annual average DBH increment of different diameter classes of trees in a mixed broadleaved-Korean pine forest
Different majuscules represent the significant difference of annual average DBH increment of diameter classⅠat P < 0.05 level under competitive pressures. Different minuscules represent the significant difference of annual average DBH increment of diameter classeⅡat P < 0.05 level under competitive pressures.
表 1 地形对阔叶红松林主要组成树种年均胸径生长量的影响
Table 1. Influence of topography on annual average DBH increment of major tree species in a mixed broadleaved-Korean pine forest
mm·a-1 mm·year-1 地形
Topography红松Pinus koraiensis 紫椴Tilia amurensis 色木槭Acer mono 水曲柳Fraxinus mandshurica Ⅰ Ⅱ Ⅰ Ⅱ Ⅰ Ⅱ Ⅰ Ⅱ 坡向
Slope aspect平地Flat 1.10±0.18 2.51±0.18a 0.85±0.22b 5.38±1.77a 0.73±0.07b 2.86±0.16a 1.27±0.36 2.76±0.42b 阴坡Shady slope 2.01±0.08b 0.80±0.20b 0.85±0.27b 2.22±0.09b 5.80±2.53a 半阴坡Semi-shady slope 0.73±0.15 1.76±0.12b 0.88±0.16b 2.09±0.49b 0.81±0.10b 2.19±0.18b 1.60±1.08 1.94±0.31b 半阳坡Semi-sunny slope 0.75±0.24 1.90±0.10b 1.03±0.12b 2.09±0.28b 0.89±0.11b 2.19±0.07b 0.94±0.24 2.69±0.33b 阳坡Sunny slope 0.52±0.15 2.04±0.10b 2.61±0.16a 2.38±0.32b 1.33±0.07a 2.26±0.07b 1.40±0.22 2.34±0.26b 坡度
Slope gradient<6° 1.04±0.18 2.38±0.15a 0.94±0.18b 4.73±0.18a 0.85±0.11b 2.74±0.13a 1.18±0.27 2.66±0.34 6°~15° 0.75±0.19 1.92±0.09b 1.00±0.12b 2.24±0.23b 0.81±0.05b 2.19±0.05b 1.57±0.28 2.50±0.25 15°~25° 0.70±0.20 1.99±0.11b 0.94±0.16b 2.28±0.40b 0.89±0.10b 2.32±0.15b 0.50±0.11 2.49±0.34 >25° 0.25±0.15 1.72±0.18b 2.64±1.65a 2.73±0.34b 1.25±0.16a 2.12±0.16b 1.87±0.62 2.13±0.52 坡位
Slopeposition山谷Valley 1.04±0.18 2.45±0.18a 1.12±0.27b 2.01±1.47a 0.75±0.07b 2.85±0.15a 1.22±0.29 2.69±0.35 下坡Lower slope 0.71±0.15 1.92±0.09b 1.06±0.10b 2.16±0.25b 0.73±0.05b 2.23±0.07b 1.19±0.21 2.38±0.21 上坡Upper slope 0.64±0.23 2.07±0.11b 0.87±0.11b 2.22±0.35b 0.75±0.06b 2.15±0.07b 1.68±0.53 2.80±0.46 山脊Ridge 1.80±0.04b 2.47±0.10a 2.10±0.30b 1.37±0.59a 2.11±0.06b 1.40±1.11 地形
Topography冷杉Abies nephrolepis 枫桦Betula costata 春榆Ulmus japonica 青楷槭Acer tegmentosum Ⅰ Ⅱ Ⅰ Ⅱ Ⅰ Ⅱ Ⅰ Ⅱ 坡向
Slope aspect平地Flat 1.45±0.27 2.57±0.26 0.61±0.12 2.74±0.42 1.36±0.26 2.76±1.13 1.91±0.24 2.89±0.80 阴坡Shady slope 1.25±0.47 2.32±0.44 0.57±0.07 1.70±0.90 1.24±0.39 半阴坡Semi-shady slope 1.06±0.20 2.20±0.23 0.31±0.07 2.46±0.24 1.40±0.20 4.00±2.20 2.20±0.19 1.45±0.26 半阳坡Semi-sunny slope 0.80±0.12 2.10±0.14 0.57±0.10 2.94±0.37 1.42±0.25 3.67±0.95 1.83±0.12 2.17±0.37 阳坡Sunny slope 1.16±0.13 2.31±0.16 0.55±0.08 2.87±0.29 1.00±0.12 3.84±0.88 1.92±0.21 2.32±0.39 坡度Slope gradient <6° 1.45±0.22 2.67±0.28 0.62±0.11 2.93±0.33 1.43±0.23 3.43±0.74 1.92±0.18 2.92±0.66 6°~15° 1.01±0.11 2.20±0.11 0.46±0.07 2.70±0.25 0.94±0.15 3.12±0.64 1.86±0.11 2.36±0.34 15°~25° 0.82±0.13 2.13±0.17 0.56±0.10 2.68±0.33 1.21±0.20 3.33±0.72 2.12±0.20 1.64±0.20 >25° 1.14±0.19 2.23±0.36 0.20±0.09 2.55±0.56 1.28±0.29 1.92±0.53 1.74±0.97 坡位Slope position 山谷Valley 1.58±0.25a 2.54±0.25 0.60±0.12 2.99±0.41 1.31±0.22 4.03±1.57 1.94±0.22 2.89±0.80 下坡Lower slope 0.96±0.10b 2.32±0.12 0.51±0.07 2.76±0.22 1.22±0.14 3.80±0.60 1.91±0.10 2.07±0.28 上坡Upper slope 1.03±0.13b 1.98±0.14 0.48±0.08 2.68±0.33 0.93±0.27 2.44±1.22 2.01±0.23 2.16±0.41 山脊Ridge 2.72±1.06 0.48±0.08 2.55±0.56 0.87±0.77 注:Ⅰ表示1 cm≤DBH<10 cm,Ⅱ表示DBH≥10 cm;表中数值为平均值±标准误;不同小写字母表示不同地形下差异显著(P<0.05)。Notes:Ⅰ, 1 cm≤DBH<10 cm; Ⅱ, DBH≥10 cm; Data in table is mean±SE; Different minuscules represent significant difference at P<0.05 level on different topography conditions. 表 2 竞争对阔叶红松林主要组成树种年均胸径生长量的影响
Table 2. Influence of competition on annual average DBH increment of major tree species in a mixed broadleaved-Korean pine forest
mm·a-1 mm·year-1 竞争指数Competition index(CI) 红松Pinus koraiensis 紫椴Tilia amurensis 色木槭Acer mono 水曲柳Fraxinus mandshurica Ⅰ Ⅱ Ⅰ Ⅱ Ⅰ Ⅱ Ⅰ Ⅱ <5 2.34±0.06a 2.12±0.07a 1.87±0.13a 2.91±0.39a 1.36±0.06a 2.46±0.13a 2.38±0.69a 2.56±0.18 5~10 0.88±0.14b 1.47±0.13b 1.09±0.13b 1.69±0.26b 1.11±0.08b 1.44±0.15b 1.39±0.22b 1.40±0.55 >10 0.98±0.15b 1.71±0.25b 0.99±0.08b 1.60±0.10b 0.81±0.43c 1.11±0.42b 0.86±0.18b 竞争指数Competition index(CI) 冷杉Abies nephrolepis 枫桦Betula costata 春榆Ulmus japonica 青楷槭Acer tegmentosum Ⅰ Ⅱ Ⅰ Ⅱ Ⅰ Ⅱ Ⅰ Ⅱ <5 2.03±0.07a 2.38±0.10a 1.92±0.16a 2.80±0.17 1.25±0.34 2.59±0.37a 3.09±0.42a 2.38±0.26 5~10 1.11±0.08b 1.50±0.16b 1.05±0.10b 2.13±0.71 1.28±0.16 1.31±0.14b 2.24±0.25b 2.16±0.22 >10 1.01±0.11b 1.43±0.39b 0.60±0.08c 1.23±0.18 1.08±0.12b 1.79±0.09c 2.08±0.20 注:Ⅰ表示1 cm≤DBH<10 cm,Ⅱ表示DBH≥10 cm;不同小写字母表示不同竞争指数等级下差异显著(P<0.05)。Notes:Ⅰ, 1 cm≤DBH<10 cm; Ⅱ, DBH≥10 cm; Different minuscules represent significant difference at P<0.05 level under different competition index grades. -
[1] COSTA F R C, MAGNUSSON W E, LUIZAO R C. Mesoscale distribution patterns of Amazonian understorey herbs in relation to topography, soil and watersheds[J]. Journal of Ecology, 2005, 93(5): 863-878. doi: 10.1111/j.1365-2745.2005.01020.x [2] BOHLMAN S A, LAURANCE W F, LAURANCE S G, et al. Importance of soils, topography and geographic distance in structuring central Amazonian tree communities[J]. Journal of Vegetation Science, 2008, 19(6): 863-874. doi: 10.3170/2008-8-18463 [3] TILMAN D, PACALA S. The maintenance of species richness in plant communities[M]. Chicago: The University of Chicago Press, 1993: 13-25. [4] 刘鑫, 毕华兴, 李笑吟, 等.晋西黄土区基于地形因子的土壤水分分异规律研究[J].土壤学报, 2007, 44(3): 411-417. doi: 10.3321/j.issn:0564-3929.2007.03.005 LIU X, BI H X, LI X Y, et al. Variation of soil moisture in relation to topographic factors in loess region of West Shanxi[J]. Acta Pedologica Sinica, 2007, 44(3): 411-417. doi: 10.3321/j.issn:0564-3929.2007.03.005 [5] MCCOOL D K, BROWN L C, FOSTER G R, et al. Revised slope steepness for the universal loss soil equation[J]. Transactions of the ASAE, 1987, 30: 1387-1396. doi: 10.13031/2013.30576 [6] 张地, 张育新, 曲来叶, 等.坡位对东灵山辽东栎林土壤微生物量的影响[J].生态学报, 2012, 32(20): 6412-6421. http://d.old.wanfangdata.com.cn/Periodical/stxb201220016 ZHANG D, ZHANG Y X, QU Y L, et al. Effects of slope position on soil microbial biomass of Quercus liaotungensis forest in Dongling Mountain[J]. Acta Ecologica Sinica, 2012, 32(20): 6412-6421. http://d.old.wanfangdata.com.cn/Periodical/stxb201220016 [7] GASTON K J. Global patterns in biodiversity[J]. Natuer, 2000, 405: 220-226. doi: 10.1038/35012228 [8] 薛建辉.森林生态学[M].北京:中国林业出版社, 2006. XUE J H. Forest ecology[M]. Beijing: China Forestry Publishing House, 2006. [9] 于健, 徐倩倩, 刘文慧, 等.长白山东坡不同海拔长白落叶松径向生长对气候变化的响应[J].植物生态学报, 2016, 40(1): 24-35. http://d.old.wanfangdata.com.cn/Periodical/zwstxb201601003 YU J, XU Q Q, LIU W H, et al. Response of radial growth to climate change for Larix olgensis along an altitudinal gradient on the eastern slope of Changbai Mountain, Northeast China[J]. Chinese Journal of Plant Ecology, 2016, 40(1): 24-35. http://d.old.wanfangdata.com.cn/Periodical/zwstxb201601003 [10] YU D, WANG G G, DAI L M. Dendroclimatic analysis of Betula ermanii forests at their upper limit of distribution in Changbai Mountain, Northeast China[J]. Forest Ecology and Management, 2007, 240: 105-113. doi: 10.1016/j.foreco.2006.12.014 [11] NAKASHIZUKA T. Species coexistence in temperate, mixed deciduous forests[J]. Trends in Ecology and Evolution, 2001, 16: 205-210. doi: 10.1016/S0169-5347(01)02117-6 [12] WYCHOFF P H, CLARK J S. The relationship between growth and mortality for seven cooccurring tree species in the southern Appalachian Mountains[J]. Journal of Ecology, 2002, 90: 604-615. doi: 10.1046/j.1365-2745.2002.00691.x [13] PEREZ-RAMOS I M, OURCIVAL J M, LIMOUSIN J M, et al. Mast seeding under increasing drought: results from a long-term data set and from a rainfall exclusion experiment[J]. Ecology, 2010, 91: 3057-3068. doi: 10.1890/09-2313.1 [14] STOLL P, WEINER J, SCHMID B. Growth variation in a natural established population of Pinus sylvestris[J]. Ecology, 1994, 75: 660-670. doi: 10.2307/1941724 [15] ZAVALA M A, ANGULO O, LOPEZ-MARCOS J C, et al. An analytical model of stand dynamics as a function of tree growth, mortality and recruitment: the shade tolerance-stand structure hypothesis revisited[J]. Journal Theoretical Biology, 2007, 244(3): 440-450. doi: 10.1016/j.jtbi.2006.08.024 [16] COOMES D A, KUNSTLER G, CANHAM C D, et al. A greater range of shade-tolerance niches in nutrient-rich forests: an explanation for positive richness-productivity relationships[J]. Journal of Ecology, 2009, 97(4): 705-717. doi: 10.1111/j.1365-2745.2009.01507.x [17] RIYOU T, HINO T, NAOKI A, et al. Variation in tree groeth, mortality and recruitment among topographic postions in a warm temperate forest[J]. Journsl of Vegetation Science, 2006, 17: 281-290. doi: 10.1111/j.1654-1103.2006.tb02447.x [18] SHEN Y, SANTIAGO L S, SHEN H, et al. Determinants of change in subtropical tree diameter growth with ontogenetic stage[J]. Oecologia, 2014, 175(4): 1315-1324. doi: 10.1007/s00442-014-2981-z [19] HERWITZ S R, YOUNG S S. Mortality, recruitment, and growth rates of montane tropical rain forest canopy trees on mount Bellenden-Ker, Northeast Queensland, Australia[J]. Biotropica, 1994, 26(4): 350-361. doi: 10.2307/2389228 [20] GRUBB P J. Control of forest growth and distribution on wet tropical mountains: with special reference to mineral nutrition[J]. Annual Review of Ecology and Systematics, 1977, 8: 83-107. doi: 10.1146/annurev.es.08.110177.000503 [21] TANNER E V J. Four montane rain forests of Jamaica: a quantitative characterization of the floristics, the soils and the foliar mineral levels, and a discussion of the interrelations[J]. Journal of Ecology, 1977, 65(3): 883-918. doi: 10.2307/2259385 [22] BRUIJNZEEL L A, VENEKLAAS E V. Climatic conditions and tropical montane forest productivity: the fog has not lifted yet[J]. Ecology, 1998, 79: 3-9. doi: 10.1890/0012-9658(1998)079[0003:CCATMF]2.0.CO;2 [23] HAN A R, LEE S K, SUH G U, et al. Wind and topography influence the crown growth of Picea jezoensis in a subalpine forest on Mt. Deogyu, Korea[J]. Agricultural and Forest Meteorology, 2012, 166/167: 207-214. doi: 10.1016/j.agrformet.2012.07.017 [24] 张丽云.中亚热带典型针阔混交林生长竞争与直径结构的关系[D].长沙: 中南林业科技大学, 2013. http://www.wanfangdata.com.cn/details/detail.do?_type=degree&id=Y2317230 ZHANG L Y. The relationship between competition and diameter distribution of the forest mixed with conifer and broadleaves in subtropical forest fcosytems[D]. Changsha: Central South University of Forest and Technology, 2013. http://www.wanfangdata.com.cn/details/detail.do?_type=degree&id=Y2317230 [25] DANIELS R F, BURKHART H E, CLASON T R. A comparison of competition measures for predicting growth of loblolly pine trees[J]. Canadian Journal of Forest Research, 1986, 16(6): 1230-1237. doi: 10.1139/x86-218 [26] COATES K D, CANHAM C D, LEPAGE P T. Neighborhood analyses of canopy tree competition along environmental gradients in New England forests[J]. Ecological Applications, 2006, 16(2): 540-554. doi: 10.1890/1051-0761(2006)016[0540:NAOCTC]2.0.CO;2 [27] 刘洋, 亢新刚, 郭艳荣, 等.长白山主要树种空间分布特征对胸径生长量的影响[J].东北林业大学学报, 2013, 41(11): 1-4. doi: 10.3969/j.issn.1000-5382.2013.11.001 LIU Y, KANG X G, GUO Y R, et al. Influence of spatial distribution characteristics to diameter at breast height increment for main tree species in Changbai Mountain[J]. Journal of Northeast Forestry University, 2013, 41(11): 1-4. doi: 10.3969/j.issn.1000-5382.2013.11.001 [28] COOMES D A, ALLEN R B. Effects of size, competition and altitude on tree growth[J]. Journal of Ecology, 2007, 95(5): 1084-1097. doi: 10.1111/j.1365-2745.2007.01280.x [29] SMALE M C, RICHARDSON S J, HURST J M. Diameter growth rates of tawa (Beilschmiedia tawa) across the middle North Island, New Zealand: implications for sustainable forest management[J]. New Zealand Journal of Forestry Science, 2014, 44(1): 20-25. doi: 10.1186/s40490-014-0020-9 [30] 赵雪, 刘妍妍, 金光泽.地形对阔叶红松林幼苗更新的影响[J].应用生态学报, 2013, 24(11): 3035-3042. http://d.old.wanfangdata.com.cn/Periodical/yystxb201311003 ZHAO X, LIU Y Y, JIN G Z. Effects of topography on seedling regeneration in a mixed broadleaved-Korean pine forest in Xiaoxing'an Mountains, Northeast Chian[J]. Chinese Journal of Applied Ecology, 2013, 24(11): 3035-3042. http://d.old.wanfangdata.com.cn/Periodical/yystxb201311003 [31] 赵雪, 徐丽娜, 金光泽.地形对典型阔叶红松林灌木更新的影响[J].生物多样性, 2015, 23(6): 767-774. http://d.old.wanfangdata.com.cn/Periodical/swdyx201506009 ZHAO X, XU L N, JIN G Z. Effect of topography on shurb regeneration in a mixed broadleaved-Korean pine forest in the Xiaoxing'an Mountains[J]. Biodiversity Science, 2015, 23(6): 767-774. http://d.old.wanfangdata.com.cn/Periodical/swdyx201506009 [32] 刘妍妍, 金光泽.地形对小兴安岭阔叶红松(Pinus koraiensis)林粗木质残体的影响[J].生态学报, 2009, 29(3): 1398-1407. doi: 10.3321/j.issn:1000-0933.2009.03.037 LIU Y Y, JIN G Z. Influence of topography on coarse woody debris in a mixed broadleaved-Korean pine forest in Xiaoxing'an Mountains, China[J]. Acta Ecologica Sinica, 2009, 29(3): 1398-1407. doi: 10.3321/j.issn:1000-0933.2009.03.037 [33] 杨光.东北东部山区部分主要树种邻体影响半径研究[D].哈尔滨: 东北林业大学, 2006. http://cdmd.cnki.com.cn/Article/CDMD-10225-2006110393.htm YANG G. Study on the neighborhood influence radius of partial main tree species in Northeastern China[D]. Harbin: Northeast Forestry University, 2006. http://cdmd.cnki.com.cn/Article/CDMD-10225-2006110393.htm [34] HEGYI F. A simulation model for managing jack-pine stands[C]//FRIES J. Growth models for tree and stand simulation. Stockholm: Royal College of Forestry, 1974: 74-90. [35] 徐丽娜, 金光泽.小兴安岭凉水典型阔叶红松林动态监测样地:物种组成与群落结构[J].生物多样性, 2012, 20(4): 470-481. http://d.old.wanfangdata.com.cn/Periodical/swdyx201204009 XU L N, JIN G Z. Species composition and community structure of a typical mixed broadleaved-Korean pine (Pinus koraiensis) forest plot in Liangshui Nature Reserve, Northeast China[J]. Biodiviersity Science, 2012, 20(4): 470-481. http://d.old.wanfangdata.com.cn/Periodical/swdyx201204009 [36] WRIGHT S J, KAORU K, KRAFT N J B, et al. Functional traits and the growth-mortality trade-off in tropical trees[J]. Ecology, 2010, 91: 3664-3674. doi: 10.1890/09-2335.1 [37] 周以良, 董世林, 聂绍荃, 等.黑龙江树木志[M].哈尔滨:黑龙江省科学技术出版社, 1986. ZHOU Y L, DONG S L, NIE S Q, et al. Ligneous flora of Heilongjiang[M]. Harbin: Heilongjiang Science and Technology Press, 1986. [38] 田锴, 陈磊, 米湘成, 等.亚热带常绿阔叶林木本植物幼苗分布格局以及其对生境过滤的响应[J].科学通报, 2013, 58(34): 3561-3569. http://www.cnki.com.cn/Article/CJFDTotal-KXTB201334013.htm TIAN K, CHEN L, MI X C, et al. The effect of habitat filtering on tree seedling distribution in a subtropical evergreen broadleaf forest in China[J]. Chinese Science Bulletin, 2013, 58(34): 3561-3569. http://www.cnki.com.cn/Article/CJFDTotal-KXTB201334013.htm [39] 张丽鹏, 杨雨春, 赵珊珊, 等.环境因子对长白山区天然核桃楸林生长的影响[J].中国农业通报, 2014, 30(4): 34-41. http://d.old.wanfangdata.com.cn/Periodical/zgnxtb201404007 ZHANG L P, YANG Y C, ZHAO S S, et al. The impact of environmental factors on the growth of Juglans mandshurica in nature forest of Changbai Mountains[J]. Chinese Agricultural Science Bulletin, 2014, 30(4): 34-41. http://d.old.wanfangdata.com.cn/Periodical/zgnxtb201404007 [40] HUTCHINSON T F, BOERNER R E J, IVERSON L R, et al. Landscape patterns of understory composition and richness across a moisture and nitrogen mineralization gradient in Ohio(U. S. A.) Quercus forest[J]. Plant Ecology, 1999, 144: 177-189. doi: 10.1023/A:1009804020976 [41] TOKUCHI N, TAKEDA H, YOSHIDA K, et al. Topographical variations in a plant-soil system along a slope on Mt Ryuoh, Japan[J]. Ecological Research, 1999, 14: 361-369. doi: 10.1046/j.1440-1703.1999.00309.x [42] 闫兴富, 曹敏.濒危树种望天树大量结实后幼苗的生长和存活[J].植物生态学报, 2008, 32(1): 55-64. doi: 10.3773/j.issn.1005-264x.2008.01.006 YAN X F, CAO M. Seedling growth and survival of the endangered tree species Shorea wantianshuea after a mast-fruiting event[J]. Journal of Plant Ecology, 2008, 32(1): 55-64. doi: 10.3773/j.issn.1005-264x.2008.01.006 [43] BIN Y, LIN G J, LI B H, et al. Seedling recruitment patterns in a 20 ha subtropical forest plot: hints for niche-based processes and negative density dependence[J]. European Journal of Forest Research, 2011, 131(2): 453-461. doi: 10.1007/s10342-011-0519-z [44] KARIUKI M, ROLFE M, SMITH R G B, et al. Diameter growth performance varies with species functional-group and habitat characteristics in subtropical rainforests[J]. Forest Ecology and Management, 2006, 225(1-3): 1-14. doi: 10.1016/j.foreco.2005.07.016 [45] 曾小平, 赵平, 蔡锡安, 等. 25种南亚热带植物耐阴性的初步研究[J].北京林业大学学报, 2006, 28(4): 88-95. doi: 10.3321/j.issn:1000-1522.2006.04.017 ZENG X P, ZHAO P, CAI X A, et al. Study on shade-tolerance of 25 low subtropical plants[J]. Journal of Beijing Forestry University, 2006, 28(4): 88-95. doi: 10.3321/j.issn:1000-1522.2006.04.017 [46] HARMS K E, CONDIT R, HUBBELL S P, et al. Habitat associations of trees and shrubs in a 50-ha neotropical forest plot[J]. Journal of Ecology, 2001, 89: 947-959. doi: 10.1111/j.1365-2745.2001.00615.x [47] CORNWELL W K, SCHWILK D W, ACKERLY D D. A trait-based test for habitat filtering convex hull volume[J]. Ecology, 2006, 87(6): 1465-1471. doi: 10.1890/0012-9658(2006)87[1465:ATTFHF]2.0.CO;2 [48] KRAFT N J B, VALENCIA R, ACKERLY D D. Functional traits and niche-based tree community assembly in an Amazonian forest[J]. Science, 2008, 322: 580-582. doi: 10.1126/science.1160662 [49] WEBB C O, PEART D R. Habitat associations of trees and seedlings in a Bornean rain forest[J]. Journal of Ecology, 2000, 88: 464-478. doi: 10.1046/j.1365-2745.2000.00462.x [50] 童鑫.从种群遗传和群落组成的空间结构研究群落维持机制[D].上海: 华东师范大学, 2015. TONG X. Exploring commuity assemble through the lens of spatial structure: from population genetics to community composition[D]. Shanghai: East China Normal University, 2015. [51] 张泽浦, 方精云, 菅诚.邻体竞争对植物个体生长速率和死亡概率的影响:基于日本落叶松种群试验的研究[J].植物生态学报, 2000, 24(3): 340-345. doi: 10.3321/j.issn:1005-264X.2000.03.016 ZHANG Z P, FANG J Y, JIAN C. Effects of competition on growth rate and probability of death of plant individuals a study based on nursery experiments of Larix leptolrpis populations[J]. Journal of Plant Ecology, 2000, 24(3): 340-345. doi: 10.3321/j.issn:1005-264X.2000.03.016 [52] 童跃伟, 项文化, 王正文, 等.地形、邻株植物及自身大小对红楠幼树生长与存活的影响[J].生物多样性, 2013, 21(3): 269-277. http://d.old.wanfangdata.com.cn/Periodical/swdyx201303004 TONG Y W, XIANG W H, WANG Z W, et al. Effects of topography, neighboring plants and size-dependence of Machillus thunbergii on sapling growth and survivorship[J]. Biodiversity Science, 2013, 21(3): 269-277. http://d.old.wanfangdata.com.cn/Periodical/swdyx201303004 [53] HERWITZ S R, SLYE R E, TURTON S M. Long-term survivorship and crown area dynamics of tropical rain forest canopy tress[J]. Ecology, 2000, 81(2): 585-597. doi: 10.1890/0012-9658(2000)081[0585:LTSACA]2.0.CO;2 [54] URIARTE M, CANHAME C D, THOMPSON J, et al. A neighborhood analysis of tree growth and survival in a hurricane-driven tropical forest[J]. Ecological Monographs, 2004, 74(4): 591-614. doi: 10.1890/03-4031 [55] WYCKOFF P H, CLARK J S. Tree growth prediction using size and exposed crown area[J]. Canadian Journal of Forest Research, 2005, 35(1): 13-20. doi: 10.1139/x04-142 [56] COATES K D, CANHAM C D, LEPAGE P T. Above-versus below-ground competitive effects and responses of a guild of temperate tree species[J]. Journal of Ecology, 2009, 97(1): 118-130. doi: 10.1111/j.1365-2745.2008.01458.x [57] 王政权, 王军邦, 孙志虎, 等.水曲柳苗木地下竞争与地上竞争的定量研究[J].生态学报, 2003, 23(8): 1512-1518. doi: 10.3321/j.issn:1000-0933.2003.08.007 WANG Z Q, WANG J B, SUN Z H, et al. Quantitative study of below-and above-ground competitions in mandchurican ash seedlings[J]. Acta Ecologica Sinica, 2003, 23(8): 1512-1518. doi: 10.3321/j.issn:1000-0933.2003.08.007 -