【作者】 叶绍明；

【导师】 郑小贤； 金大刚；

【作者基本信息】 北京林业大学 ， 森林经理学， 2007， 博士

【摘要】 由于全球工业化和人们生活水平的提高，对木材的需求量迅速增长，而全球森林资源总量却急剧下降，因此，世界各国都致力于发展工业人工林以缓解这一矛盾。我国是森林资源不足、木材及木质原料供需矛盾更为突出的国家，在针对这一问题所采取的一系列对策中，发展工业人工林是关键的措施之一。桉树因其具有速生、高产、优质的特点而被世界各大洲广泛引种栽培，也是我国引种成功的一类树种，更是南方地区速丰林基地的首选树种，目前我国桉树人工林面积已达170万hm~2，其中广西桉树速丰林基地已达53.36万hm~2，名列全国桉树速丰林基地建设榜首。在这样的背景之下，如何科学合理地进行桉树工业人工林的经营，是迫切需要解决的科学问题。本研究通过对桉树工业人工林的长期定位观测，采用定性判断与定量化、模型化相结合，微观分析与宏观综合相结合，还原论与整体论相结合，野外调查与科学推理相结合等系统科学整合研究的理论与方法，研究了桉树工业人工林的生长和结构规律、林分密度效应规律、地力效应规律、生物量和生产力及植物多样性特征，并在此基础上，提出桉树工业人工林经营目标、理论模式及经营类型水平的主要经营模式，构建桉树工业人工林可持续经营指标体系，为桉树工业人工林可持续经营提供理论依据和技术支持。主要研究成果如下：1、首次采用定位观测方法研究了不同连栽代次尾巨桉工业人工林生长规律、直径结构分布规律、林地土壤理化性质变化动态、生物量及生产力分布格局及植物多样性的变化动态，为连栽桉树工业人工林的经营管理提供科学依据。(1) 1代至3代不同连栽代次尾巨桉工业人工林林分胸径、树高和材积生长差异不显著，生长过程基本一致。不同连栽代次尾巨桉胸径生长分别在第2a和第5a出现2个生长高峰，但第2个生长高峰明显低于第1个生长高峰；不同连栽代次尾巨桉均保持较高的高生长，7a生树高平均生长量均在2.5m以上，树高生长高峰出现在第2a，生长高峰后连年生长量明显下降；不同连栽代次尾巨桉林分单位面积蓄积平均生长量峰值出现的年份为第5a，即尾巨桉工业人工林的数量成熟龄为5a。(2)采用聚类分析方法将连栽尾巨桉林分生长过程划分为3个阶段，即1～2a为快速生长阶段，胸径、树高生长迅速；3～5a为一般生长阶段，胸径、树高生长相对稳定，材积连年生长量出现最高峰；6～7a为缓慢生长阶段，胸径、树高生长明显减缓，材积平均生长量趋于平缓。(3)β分布函数能较好地描述尾巨桉及尾叶桉林分直径分布规律，拟合样地接受率分别为85.19％和93.33％；尾巨桉及尾叶桉林分直径分布的变动系数均随年龄的增大而增大，即林分直径随年龄的增长分化程度增大，直径分布范围变宽；林分直径分布曲线顶峰右偏，即尾巨桉和尾叶桉工业人工林林分直径分布大径材占多数。(4)连栽对桉树工业人工林林地土壤的物理及化学性质均产生负效应，即随连栽代次的增加，土壤容重、土壤孔隙度、通气度、最大持水量、土壤的pH值、土壤有机质、全N、全P、全K、水解N均随连栽代次的增加而减少，连栽引起土壤肥力下降的趋势明显。(5)连载尾巨桉工业人工林植物多样性指数、均匀度指数、丰富度指数随着连载代次的增加而明显下降，即林下植物多样性随连载代次的增加而减少，物种生态优势度增加。(6)连载更新尾巨桉工业人工林第1代、第2代、第3代林分及群落的生物量及生产力基本相同，但随着连栽代次的增加，尾巨桉林下植被及枯落物生物量明显下降。不同连栽代次尾巨桉林分器官生物量分配无明显差异，生物量分配的大小排序为：干材＞根系＞干皮＞枝条＞叶。2、通过分析尾巨桉植苗更新、不同密度的萌芽更新模式之间林分生长、土壤理化性质、植物多样性、生物量及生产力的差异，提出了可有效增加林下植物多样性、植被生物量和生产力及土壤养分的萌芽更新方式及经营方式。(1)在相同密度下，尾巨桉植苗更新林分的胸径、树高、材积生长优于萌芽更新林分；萌芽更新林分胸径生长随保留密度的增大而减少，但林分树高生长差异不明显；萌芽更新林分保留2100株/hm~2时，能有效提高单位面积的蓄积量。(2)萌芽更新林地土壤容重、总孔隙度、最大持水量随萌芽保留密度的增加而增加，表现为正效应的作用规律；在相同密度条件下，植苗更新林地的土壤总孔隙度、最大持水量比萌芽更新高；萌芽更新林地土壤有机质、全N、全P、全K随萌芽保留密度的增加而增加，表现为正效应的作用规律；速效养分及交换性Ca、交换性Mg则随萌芽保留密度的增加而下降，表现为负效应的作用规律。(3)全垦植苗更新尾巨桉林分林下植物多样性指数、均匀度、物种丰富度均比萌芽更新林分低；在密度为1110株/hm~2～2100株/hm~2范围内，萌芽更新尾巨桉林分林下植物多样性指数、均匀度指数、物种丰富度随萌芽保留密度的增加而略有增加。(4)在相同密度及相同立地条件下，植苗更新尾巨桉人工林的生物量和生产力高于萌芽更新，萌芽更新林分生物量、群落生物量及生产力随萌芽保留密度的增加而增加，萌芽更新保留2100株/hm~2时，能有效提高单位面积的林地生产力。3、通过分析尾叶桉纯林、尾叶桉与马占相思混交林不同混交比例林分生长、生物量及生产力、土壤理化性质及植物多样性的差异，认为适宜混交比例的尾叶桉与马占相思混交林能有效改良土壤的物理性状、提高土壤养分和增加植物多样性。(1)在相同密度下，尾叶桉马占相思混交林胸径、树高、材积生长优于尾叶桉纯林；尾叶桉马占相思不同混交处理间林木胸径、树高、材积生长及径高比有明显差异，本研究尾叶桉与马占相思以1：1.6混交，尾叶桉676株/hm~2，马占相思1051株/hm~2为最佳混交模式。(2)尾叶桉马占相思混交林的土壤容重比尾叶桉纯林低，而土壤总孔隙度、毛管孔隙度、非毛管孔隙度和持水量比纯林高，混交林的土壤结构优于纯林；混交林的土壤有机质、全N、全P、全K、交换性Ca、交换性Mg均比纯林高，营造尾叶桉马占相思混交林能有效增加土壤的营养元素。(3)尾叶桉和马占相思以2：1比例混交林分的植物多样性指数、均匀度指数、物种丰富度指数比尾叶桉纯林高，但尾叶桉马占相思以1：1.6比例混交林分的林下植物多样性指数、均匀度指数和物种丰富度则比纯林低，不同混交比例的混交林不完全能有效地增加林下植物的多样性，只有选择合适的混交比例，调节有利于林下植物发育生长的光照因子，是维持林下植物正常生长及维持植物种类多样性的关键。(4)在相同林分密度时，尾叶桉纯林林分生物量比尾叶桉马占相思混交林林分生物量低，表明营造生态位有差异的混交林能充分利用林地空间，提高林分生产力。4、首次采用灰色关联分析方法和趋势面分析方法，揭示了不同更新模式桉树工业人工林植物多样性与土壤理化性质变化、生物量的关系。(1)不同更新模式桉树工业人工林植物多样性指数、物种丰富度、均匀度指数与土壤物理性质存在同一的关联性，即多样性指数和物种丰富度与土壤空隙度的关联最大，与土壤容重的关联最小，而均匀度指数则与土壤持水量的关联最大；植物多样性物种丰富度、Shannon-wiener多样性指数和均匀度与土壤微量元素关联最大，速效养分、有机质和pH值次之，与交换性Ca、交换性Mg的关联最小。(2)采用趋势面分析结果表明，不同连栽代次尾巨桉林地植物多样性增加则林地根系生物量和林下植被生物量显著增加，而对林分生物量、干材生物量、干皮生物量、枝条生物量、叶生物量的影响不大。5、揭示尾叶桉工业人工林密度效应规律，建立尾叶桉工业人工林密度效应模型并进行生产弹性分析和边际分析，推算出不同地位指数条件下的合理造林密度。(1)尾叶桉短轮伐期工业人工林在相同密度条件下，不同株行距配置方式对林分的胸径、树高、单株材积和单位面积蓄积生长量无显著影响。在不同密度条件下，林分的平均胸径随密度的增大而减小，表现有负效应的作用规律；在一定的密度范围内，林分每公顷蓄积量随密度的增加而增加，表现出正效应的作用规律，而密度增加到一定程度后，林分单位蓄积量随密度的增加而下降，表现为负效应的作用规律。(2)大径材培育模式尾巨桉林分平均胸径随林分密度的增加而减小，表现为负效应的作用规律，但密度对林分树高、高径比、单株平均材积没有相同的作用规律。(3)提出尾叶桉短轮伐期工业人工林密度效应抛物线式改进模型。生产弹性分析的结果表明，尾叶桉密度效应处于负效应阶段，当密度减少1％时，平均单株材积增加0.4520％；边际产量分析结果当其它条件不变时，每公顷面积上增加1株林木，单株平均材积减少0.000032m~3；优势木高每增加1.0m，单株平均材积增加0.001m~3；当林分年龄等于地位指数推算的基准年龄(6a)时，15至20地位指数尾叶桉工业人工林每公顷最优密度分别为1237株、1492株、1779株、2100株、2458株和2853株。6、分析了传统森林成熟种类存在的局限性，对桉树工业人工林经营的时间决策提出了蓄积量最大收获期、工艺最佳收获期和经济收益最大收获期的概念，同时将三类收获期作为整体提出综合收获期的概念，给传统森林成熟的概念赋于新的内涵，丰富和发展了森林经营时间决策的有关概念和基础理论。7、首次提出桉树工业人工林林分水平可持续经营评价指标体系，提出构建林分级可持续指标体系的理论依据、实践依据、指导思想和基本原则，构建了一套包括资源、经济、生态、林地生产力、综合生产潜力等5个层次23个指标组成的林分级可持续经营指标体系，为今后开展相关方面的研究提供了理论和方法上的借鉴。8、首次提出桉树工业人工林包括经济和生态两大类的经营目标体系，提出包括经营条件、经营原则、调整理论、评价理论等效益型森林经营理论，丰富和发展了森林经营的基本理论。9、首次系统提出桉树工业人工林林分水平森林经营模式和经营技术，包括连栽模式、萌芽更新模式、混交模式及大径材培育模式。更多还原

【Abstract】 Global industrialization and the improvement of people’s living result in the rapid growth of timber demand, but global forest resources decrease sharply. Therefore, Countries in the world vigorously develop industrial plantations to alleviate the contradiction between supply and demand for timber and forest products. For China’s forest resources shortage and contradiction between supply and demand for timber and wooden materials, industrial plantations development is one of key measurements to solve those problems. Eucalyptus is popularly planted all over the world because of rapid growth, high yield, good quality. Eucalyptus, as well as Populusspp and Pinusspp, are regarded as world three rapid and high-yield forests. It is one of successful introduction species, and even preferred species in the rapid and high-yield forest bases of the southern region. In the present, Eucalyptus plantation in China has reached 1.7 million hm~2 and the rapid and high-yield forest bases in Guangxi have reached 533,600 hm~2 which ranks the first in the rapid and high-yield forest bases of china’s Eucalyptus. In this background, it is an urgent problem about how to scientifically and reasonably manage Eucalyptus industrial plantation.In this study, by long-term positional observation, the theory and method of integrated system science such as combinations of qualitative judgment and quantification, modeling, micro-analysis and macro-synthesis, holism and reductionism, field surveys and scientific reasoning were used to study the growth and structure law, stand density effect law, soil effect, biomass, productivity and plant diversity of Eucalyptus industrial plantation. Based on the above researches, objectives, theory model and the management level model of Eucalyptus industrial plantation management were proposed, and index system of Eucalyptus industrial plantation sustainable management is constructed, which afford the theoretical basis and technological support for Eucalyptus industrial plantation sustainable management. The main results were as followed:1 、 Growth law, diameter structure law, dynamic changes of soil physical and chemical properties, biomass, productivity distribution patterns and plant diversity about different continuous-planting rotations of E. urophylla × E. grandis were researched by long-term positional observation for the first time, which provide E. urophylla x E. grandis industrial plantation management for a theoretical basis.(1) For different continuous-planting rotations of E. urophylla × E. grandis industrial plantation from the first to third generation, their differences in DBH, height and volume growth were not significant and growth processes were similar. For different continuous-planting rotations of E. urophylla × E. grandis, their DBH growth reached the growth peaks in the 2nd year and the 5th year, but the latter was significantly lower than the former; All continuous-planting rotations of E. urophylla × E. grandis kept higher height growth so that the average increment of 7 years-old height was beyond 2.5m, and the height annual increment decreased obviously after growth peak at the 2nd year; the average increment stock of volume per unit area of stand in different continuous-planting rotations of E. urophylla × E. grandis reached the maximum in the 5th year, namely quantitative mature age(QMA) of E. urophylla × E. grandis industrial plantation is 5a.(2) The growing process about rotation stands of E. urophylla × E. grandis were divided into three stages by cluster analysis. In the fast growing phase from 1a to 2a, DBH and height grew quickly; In the common growing phase from 3a to 5a, DBH and height relatively grew stably and annual volume growth arrived at the maximum; In the slow growing phase from 6a to 7a, DBH and height decreased obviously and the average volume growth became slow.(3) Stand diameter distribution disciplines of E. urophylla × E. grandis and Eucalyptus urophylla were described well by β distribution function and the plot acceptance rate were 85.19% and 93.33% respectively. With the age increasing, the variant coefficient of stand diameter distribution disciplines of the two stands increased, namely differentiated level of stand diameter increased and diameter distribution range became wide; stand diameter distribution curve inclined to the right in the peak, namely large diameter timber held the majority in stand diameter distribution of E. urophylla × E. grandis and Eucalyptus urophylla.(4) Continuous planting renovation occurred negative effects of on soil physical and chemical properties of Eucalyptus industrial plantation , namely soil bulk density, soil porosity, aerating degree, the maximum water holding capacity, pH, soil organic matter, total N, total P, total K and hydrolysable nitrogen decreased with the increase of continuous planting rotations. Continuous planting rotations obviously affected soil fertility decreasing trend.(5) The continuous copping had obvious effects on reducing the diversity index, evenness index, richness index in continuous-planting rotations of E. urophylla x E. grandis industrial plantation, namely the plant diversity under forest decreased with the increase of continuous planting rotations, but ecological dominance increased.(6) The biomass and productivity of stand and community were alike in continuous planting rotations of regeneration E. urophylla × E. grandis from the 1st generation to 3rd generation, but understory vegetation and litter biomass in E. urophylla × E. grandis decreased with the increase of continuous planting rotations. Stand organs biomass distributions were not obvious in different rotations, the sequences were as follows: stock > root>bark>branch>leaf.2、 Differences in stand growth, biomass, productivity, soil physical and chemical properties and plant diversity were revealed about E. urophylla × E. grandis in planting regeneration and in sprout regeneration of different densities. In addition, the regeneration and management patterns were put forward to benefit effectively plant diversity, vegetation biomass, productivity and soil nutrients.(1) In the same density, BHD, height and volume of E. urophylla × E. grandis in planting regeneration were better than those of E. urophylla × E. grandis in sprout regeneration. In the sprout regeneration stand, the BHD decreased with the increase of reserved density, but differences in stand height were not obvious; volume per unit was raised effectively in stand reserved density of 2100 per hm~2.(2) In sprout regeneration stand, soil bulk density, soil porosity, aerating degree, the maximum water holding capacity increased with the increase of reserved density, which appeared positive effects. At the same density, soil bulk density, soil porosity, aerating degree, the maximum water holding capacity in planting regeneration stand were more than those in sprout regeneration stand. With the reserved density increasing in sprout regeneration stand, soil organic matter, total N, total P, total K increased, which appeared positive effects; while soil available nutrients, exchangeable Ca and Mg decreased, which appeared negative effects.(3) Diversity index, evenness index and richness index of E. urophylla × E. grandis stand in planting regeneration with full reclamation were lower than those in sprout regeneration. In sprout regeneration, diversity index, evenness index and richness index of E. urophylla × E. grandis stand increased with the increase of reserved density.(4) Biomass and productivity of E. urophylla × E. grandis industrial plantation in planting regeneration were higher than those in sprout regeneration. And stand biomass, community biomass and productivity of E. urophylla × E. grandis industrial plantation in sprout regeneration increased with the increase of reserved density, and productivity per unit was raised in reserved density of 2100 per hm~23 、 Differences in stand growth, biomass, productivity, soil physical and chemical properties and plant diversity were revealed about the pure forests of Eucalyptus urophylla and the mixed forests of Eucalyptus urophylla and Acacia mangium in different ratios. It showed that reasonable mixed forest of Eucalyptus urophylla and Acacia mangium can effectively improve soil physical and chemical properties, soil nutrients and plant diversity.(1) In the same density, for he pure forests of Eucalyptus urophylla and mixed forests of Eucalyptus urophylla and Acacia mangium, the latter’s DBH, height, volume were better the former’s; For the above indexes and diameter-height ratio, the significant differences lied in different treatments in mixed forests. In this study, the mixed ratio 1:1.6 of Eucalyptus urophylla and Acacia mangium showed the best mixed model when 676 plnats/hm~2 in Eucalyptus urophylla and 1051 plnats/hm~2 in Acacia mangium.(2) Soil bulk density in the mixed forests of Eucalyptus urophylla and Acacia mangium was lower than that of Eucalyptus urophylla, but aerating degree, capillary porosity, non-capillary porosity and the maximum water holding capacity of mixed forests was higher in the mixed forest than those of Eucalyptus urophylla; soil organic matter, total N, total P, total K, exchangeable Ca and Mg of mixed forests were higher than those of Eucalyptus urophylla, which proved the mixed forests can effectively raise soil nutrients(3) For Eucalyptus urophylla and mixed forests of Eucalyptus urophylla and Acacia mangium in the mixed ratio of 2:1, the latter’s diversity index, evenness index and richness index were higher than the former’s. However, when the ratio of Eucalyptus urophylla: Acacia mangium was 1:1.6, the mixed forest’s diversity index, evenness index and richness index were higher than the pure forest’s. Not all mixed forests in different mixed ratios can effectively improve plant diversity. To form suitable illumination factors for promoting plant growth and development under forests, suitable mixed ratio was the key to maintain normal plant growth and plant diversity.(4) In the same density, stand biomass of Eucalyptus urophylla was lower than that of mixed forests of Eucalyptus urophylla and Acacia mangium. It showed that the mixed forests with niche difference can fully utilize forest land and improve productivity.4、 The relationships plant diversity of Eucalyptus industrial plantation between soil physical and chemical properties, as well as biomass, were revealed by grey incidence analysis and trend surface analysis for the first time.(1) By grey incidence analysis, diversity index, evenness index, richness index of Eucalyptus industrial plantation in different regenerations had the same relativity to soil physical properties, namely the most relationship lay in between diversity index or richness index and aerating degree, and the least relationship lay in between those and soil bulk density, but the most relationship lay in between those and evenness index. The most relationship lay in between richness index, Shannon-wiener index, evenness index and soil trace elements, followed by soil available nutrients, organic matter and pH, but the least relationship lay in between richness index, shannon-wiener index, evenness index and exchangeable Ca and Mg.(2) The results of trend-surface analysis showed that improvement of plant diversity in different continuous planting rotations of E. urophylla × E. grandis was improved had significant effects on root system biomass in forest land and vegetation biomass under forests, but insignificant effects on stand biomass, stock biomass, bark biomass, branch biomass and leaf biomass.5、 Density effect law of Eucalyptus urophylla industrial plantation was revealed and that model was proposed. Suitable planting densities in different site index were proposed by productive elasticity analysis and marginal analysis.(1) In the same density, short-rotation E. urophylla × E. grandis industrial plantations, the different row spacing had no significant effects on DBH, height, individual volume and volume per unit. In different densities, the stand average DBH increased with the decreasing density, which appeared negative effects. Within certain density ranges, volume per hectare increased with the increasing density, which appeared positive effects. As the density increased to a certain degree, the density had negative effects on volume per hectare.(2) The average DBH of large-diameter E. urophylla × E. grandis decreased with the increasing stand density, which appeared negative effects, but density had no similar effects on height, height-diameter ratio and individual volume.(3) The parabola improved model of the density effect of short-rotation E. urophylla × E. grandis industrial plantations was raised. By productive elasticity analysis, the density effect of E. urophylla × E. grandis was in negative stage. When the density decreased by 1%, the average individual volume increased by 0.4520%; When the other conditions are the same, by marginal analysis, one tree per hectare increased and the average individual volume decreased by 0.000032m~3; when dominant trees height increased by 1.0m, the average individual volume increased by 0.001 m~3; when stand age amounted to the baseline age(6a)calculated by site index, optimum densities per hectare of E. urophylla × E. grandis industrial plantations in 15-20 site index was 1237, 1492, 1779, 2100, 2458 and 2853 respectively.6、 By analysis of limitations of mature types of traditional forest, volume largest harvest period, technology best harvest period and economic benefits as new concepts were proposed for Eucalyptus industrial plantation management time decision. Three kinds of harvest periods were used as a whole to be proposed for the concept of comprehensive harvesting period, which afforded traditional forest mature to a new meaning, enriched and developed the relative concepts and basic theories of forest management time decision.7、 It was the first time for sustainable management evaluation index system of E. urophylla ×E. grandis industrial plantations at stand level to be raised to constructed the theory, practice, guidance ideology and principles of sustainable management evaluation index system. A set of sustainable management evaluation index system at stand level, including five layers and 23 indexes, such as resources, economy, ecology, productivity and comprehensive growth potential, was constructed in order to provide theory and method references for future researches.8、 Two classes management aim system including economic and ecology were raised about E. urophylla × E. grandis industrial plantations at stand level for the first time. The industrialized forest management theory included management conditions and rules, adjustment theories, evaluation theories and so on. The above achievements enriched and developed the basic theories on forest management.9、 The forest management models and technology in E. urophylla × E. grandis industrial plantations at stand level were raised for the first time, including continuous cropping model, sprouting refreshment model, mixing model and big-diameter timber cultivating model.更多还原