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1.
不同造林技术措施对马尾松幼林生长影响的研究   总被引:6,自引:1,他引:6  
在贵州省台江县革东镇设置了反映马尾松人工造林各主要技术环节的试验林体系,以研究不同造林技术措施对马尾松幼林生长的影响。经对试验林固定样地进行连续8年的定期、定位测定,以及对测定结果进行统计分析,结果表明,在马尾松人工造林的各主要技术措施中,立地选择、种源选择和造林密度是影响幼林生长的最重要因素,整地规格对马尾松幼林生长有较明显影响,幼林施肥有一定影响,而整地方式和幼林抚育则无明显影响。在研究基础上初步提出了可供试验地区应用的马尾松工业用材林定向培育的造林技术措施。  相似文献   

2.
不同造林技术措施对湿地松幼林生长影响的研究   总被引:4,自引:0,他引:4  
在湖南攸县设置了反映湿地松人工林造林各主要技术环节的试验林体系,以研究不同造林技术措施对湿地松幼林生长的影响。经对试验林固定样地进行连续7年定期、定位观测及统计分析表明:在湿地松人工造林的各项主要技术措施中,立地选择、良种选择和造林密度是影响幼林生长的最重要因素,幼林抚育对湿地松幼林生长有较明显影响,而整地方式与规格对幼林生长无明显影响。  相似文献   

3.
分析不同幼林抚育措施对10年生马尾松林分的平均胸径、平均树高、造林保存率、单株材积及样地蓄积量生长的影响,结果表明不同的幼林抚育管理措施对马尾松造林成林及林分生长具有显著的影响。高标准的幼林抚育措施能显著促进马尾松的生长,提高林地生产力。  相似文献   

4.
通过40多年火力楠造林试验与生产实践,总结出火力楠造林技术要点:采用沙床播种、移苗上袋培育营养袋苗木;选择立地类型Ⅲ类以上林地整地,初植密度2 505~2 668株·hm~(-2),使用营养袋苗木在春季造林,选择适宜伴生树种如杉木、建柏、马尾松、米老排、红椎等营造混交林,加强幼林抚育管理,并通过多次间伐以调控林分密度,促进林木生长。  相似文献   

5.
马尾松是下川东的主要造林树种之一,在长江两岸低山丘陵上广为分布.近年来,万县地区营造了约30万亩马尾松速生丰产林,其中有较大部分生长达到了速生丰产生长指标,但亦有许多马尾松幼林生长不良的三类林分,除去经营管理的差异外,立地条件选择不当是一个重要的原因.本文着重研究下川东马尾松速生丰产林的条件,以期确定其生长适宜的区域与最优的立地组合.  相似文献   

6.
马尾松(桐棉种源)造林密度试验研究初报   总被引:6,自引:2,他引:4  
通过对马尾松幼林期造林密度定位试验观测表明,马尾松桐棉种源生长快,密度效应来得也快,4年时不同造林密度幼林生长即有显著差异。  相似文献   

7.
试验结果,土壤厚度、海拔高和整地、栽植方式、造林密度、抚育方法、混交类型是影响黄山松生长的主要立地因子和技术措施。黄山松造林时,除采用全面或带状整地、大穴栽植、初植密度每公顷4500—6750株外,还要及时对幼林松土抚育或林粮间作,并在立地条件差的山坡中上部因地制宜营造混交林。  相似文献   

8.
对沙黄松人工幼林的林分特征与结构、年生长规律、幼林生长进程以及造林效果进行了调查分析。结果表明:沙黄松人工幼林与马尾松同龄林相比,具有生长快、产量高、林分生长整齐、林分结构较稳定、形质性状优良的特点,沙黄松人工造林效果较好,可以在适宜地区推广。  相似文献   

9.
马尾松(Pinus Massoniana Lamb.)是我国亚热带地区的主要代表树种之一.它具有适应性强、生长快、用途广等特点。为了把科学的马尾松营林措施与应用的生产技术付诸生产,提高马尾松林分生产力,使之增产增益,揭示马尾松造林影响林分生长变化的立地因子,应用于大面积经营管理,将具有重要的现实价值。笔者根据合川市清平林场人工马尾松林分资料,就其在该场的生长状况进行分析,供今后在营林活动中借鉴与参考。  相似文献   

10.
皿目 林木栽培祯楠人工栽培技术试验研究池杉幼苗移栽试验与应用洞庭湖区刚竹生长调查与栽培试验关于杨树发展中的经营技术措施赤按种源苗期生长调查及适应性研究马尾松造林基地建设的几个技术问题墨西哥柏容器育苗试验球柏的特性与扦播繁殖油茶林低产原因及改造途径马尾松人工直播造林技术探讨提高马尾松造林成活率的几个主要环节杉木早期速生技术组装试验报告光皮桦的经济性状及栽培技术国外松无性苗与实生苗造林对比试验初报不同经营措施对竹林结构的影响 遗传育种杉木速生优良无性系选育6年研究报告从珠山红花油茶中选育优良无性系的研…  相似文献   

11.
Changes in biomass and soil carbon with nitrogen fertilization were simulated for a 25-year loblolly pine (Pinus taeda) plantation and for three consecutive 7-year short-rotation cottonwood (Populus deltoides) stands. Simulations were conducted for 17 locations in the southeastern United States with mean annual temperatures ranging from 13.1 to 19.4 °C. The LINKAGES stand growth model, modified to include the “RothC” soil C and soil N model, simulated tree growth and soil C status. Nitrogen fertilization significantly increased cumulative cottonwood aboveground biomass in the three rotations from a site average of 106 to 272 Mg/ha in 21 years. The equivalent site averages for loblolly pine showed a significant increase from 176 and 184 Mg/ha in 25 years with fertilization. Location results, compared on the annual sum of daily mean air temperatures above 5.5 °C (growing-degree-days), showed contrasts. Loblolly pine biomass increased whereas cottonwood decreased with increasing growing-degree-days, particularly in cottonwood stands receiving N fertilization. The increment of biomass due to N addition per unit of control biomass (relative response) declined in both plantations with increase in growing-degree-days. Average soil C in loblolly pine stands increased from 24.3 to 40.4 Mg/ha in 25 years and in cottonwood soil C decreased from 14.7 to 13.7 Mg/ha after three 7-year rotations. Soil C did not decrease with increasing growing-degree-days in either plantation type suggesting that global warming may not initially affect soil C. Nitrogen fertilizer increased soil C slightly in cottonwood plantations and had no significant effect on the soil C of loblolly stands.  相似文献   

12.
Foliage dynamics research is helpful for better understanding the process of forest production and improving silvicultural practice. However, the difficulty of measuring foliage amount has slowed down the research progress. Since leaf area of an individual tree can be reliably predicted from its diameter, growth and yield models that provide detailed information for each diameter class can be used to benefit foliage dynamics research. Simulation results from a growth and yield system for unthinned loblolly pine plantations indicated that foliage area increased with stand age, peaked between ages 36 and 51, and decreased after that. Volume growth increased with leaf area for young stands and decreased for older stands, whereas foliage efficiency consistently decreased with age. Better sites supported higher levels of leaf area index, volume growth, and foliage efficiency. Higher planting densities led to higher maximum leaf area indices and shorter time to reach that level. Initial density had no effect on foliage efficiency through time.  相似文献   

13.
Growth and yield of 12-year-old loblolly pine (Pinus taeda L.) plantations were compared among five subsoil textures, seven site preparation methods, with and without phosphorus fertilizer. Phosphorus broadcast before planting increased the mean size of the loblolly pine trees. However, soil differences significantly influenced stand survival, and the method of site preparation significantly affected total stand yield. Therefore, the influence of phosphorus on total stand yield depended on soil type and site preparation method. The site preparation-fertilizer combinations yielding the most volume per soil type were: on the Lucy, Ruston, and Wagram soils, shear-windrow site preparation with phosphorus; on the Kirvin and Shubuta soils, chop-burn-harrow site preparation without phosphorus; on the Calloway and Henry soils, double chopping without phosphorus; on the Sawyer soil, chopburn-harrow site preparation with phosphorus; and on the Boswell, Cadeville, Gore, and Susquehanna soils, shear-windrow-harrow site preparation without phosphorus. Soil differences and phosphorus fertilization influenced the incidence of fusiform rust in 12-year-old stands of loblolly pine.  相似文献   

14.
Tree diversity is an important component of biodiversity. Management intensification is hypothesized to affect tree diversity. However, evidence to support the relationship between management intensity and tree diversity in northern forests is lacking. This study examined the effects of fertilization, site preparation, and brush control on tree species diversity, shade tolerance diversity and size diversity of jack pine (Pinus banksiana Lamb.), black spruce (Picea mariana [Mill.] B.S.P.), white pine (Pinus strobus L.) and white spruce (Picea glauca [Moench] Voss) plantations, 15 years after planting in Ontario, Canada. Species diversity and shade tolerance diversity were highly correlated, so were diameter size diversity and height size diversity. Fertilization did not affect the tree diversity indices of any plantations. Species diversity and shade tolerance diversity was interactively influenced by site preparation and brush control in the black spruce, white pine, and white spruce plantations, showing that the highest diversity occurred on sites with intensive site preparation without brush control, whereas on sites with brush control, diversity was higher with least intensity of site preparation. However, in the jack pine plantation, neither species diversity nor shade tolerance diversity differed with management intensification, and is attributed to the fast capture of site resources by the planted crop trees of jack pine which minimized establishment of non-crop species. Tree size diversity increased with site preparation intensity in the jack pine and black spruce plantations, while it decreased with brush control in the white pine and white spruce plantations. We concluded that (1) the effects of management intensification on diversity of northern plantations differ with growth habit of planted crop tree species and (2) species diversity and tree size diversity tend to be highest at intermediate levels of silvicultural intensification during the stand establishment phase, supporting the intermediate disturbance hypothesis.  相似文献   

15.
目的 探讨不同良种和初植密度对杉木幼龄期断面积生长的影响及其互作效应,以揭示在这两个控制因子下杉木林断面积生长发育规律。 方法 以2012年春在福建省邵武卫闽国有林场营造的杉木良种和初植密度互作试验林为研究对象,根据8年的逐年定位观测资料,分析2个杉木种子园良种(第1代种子园良种和第3代种子园良种)和4种初植密度(1 667、3 333、5 000、6 667株·hm−2)控制下的林分断面积生长动态效应。 结果 初植密度对林分断面积生长具有极显著影响,同一林龄下,初植密度越高,林分断面积生长愈大。林分断面积生长的良种效应差异不显著,但低初植密度下(1 667和3 333株·hm−2),第3世代良种的断面积生长要高于第1世代良种,且随林龄增长这种现象愈明显。方差分析结果表明良种和初植密度间交互效应不显著,多重比较结果表明:低初植密度下,良种对断面积生长的正效应和密度对断面积生长的正效应具有叠加效应,且随林龄增长这种叠加效应愈明显,而高初植密度下(5 000和6 667株·hm−2),不同良种和密度组合下的断面积生长差异不显著。 结论 低初植密度下,杉木幼龄林分断面积生长的良种和密度效应具有叠加效应,第3世代良种初植密度为3 333株·hm−2的断面积生长显著高于第1世代良种初植密度为1 667株·hm−2,随初植密度增大,良种对林分断面积生长的影响程度逐渐减弱。  相似文献   

16.
马尾松优良种植材料现实遗传增益验证   总被引:5,自引:1,他引:4       下载免费PDF全文
利用设置在福建省武平县的马尾松遗传增益测定林材料,以验证优良种源、母树林及种子园混系的现实遗传增益。种源中试林和示范林测定结果都显示,选用优良种源具有显著的增产效果。在较好立地上,8年生时广西宁明和广东信宜种源的高径生长分别增益17%~47%和12%~25%。通过福建武平、江西吉安、广东信宜和广西宁明4处母树林子代5年生测定林材料,未发现预期显著的改良效果,有些母树林子代生长甚至低于相应试验对照。广西藤县和贵州黄平种子园混系在不同地理和立地环境上的生长表现验证了种子园混系较高的遗传增益,但这种增益估算值与测试点立地条件和种子园无性系构成有关。广西藤县种子园混系只有在较好立地上增产显著,而在较差立地上则难显其增益效果。贵州黄平种子园混系因速生和遗传稳定性高,在不同立地上都具有较高的遗传增益。  相似文献   

17.
桉树大径材培育技术研究概述   总被引:2,自引:0,他引:2  
培育大径材用于实木加工是桉树人工林发展的趋势,但桉树人工林大径级原木的培育尚缺乏经验。本文综述了国内外在桉树大径材树种选择、初植密度控制、间伐、修枝和施肥管理方面的现状及其对大径材生长和材性的影响,以期为桉树资源高效利用及大径材人工林的可持续发展提供借鉴和依据。  相似文献   

18.
Plantations cover a substantial amount of Earth's terrestrial surface and this area is expected to increase dramatically in the coming decades. Pinus plantations make up approximately 32% of the global plantation estate. They are primarily managed for wood production, but have some capacity to support native fauna. This capacity likely varies with plantation management. We examined changes in the richness and frequency of occurrence of bird species at 32 plots within a Pinus radiata plantation (a management unit comprising multiple Pinus stands) in south-eastern Australia. Plots were stratified by distance to native forest, stand age class and thinning regime. We also assessed the landscape context of each plot to determine relationships between bird assemblages and stand and landscape-level factors. Bird species richness was significantly higher at plots ≥300 m from native forest and in mature (∼20 years since planting) and old (∼27 years since planting) thinned pine stands. We were able to separate the often confounding effects of stand age and thinning regime by including old stands that had never been thinned. These stands had significantly fewer species than thinned stands suggesting thinning regime, not age is a key factor to improving the capacity of pine plantations to support native species (although an age × thinning interaction may influence this result). At the landscape level, species richness increased in pine stands when they were closer to native riparian vegetation. There were no significant differences in species composition across plots. Our study indicates the importance of stand thinning and retention of native riparian vegetation in improving the value of pine plantations for the conservation of native fauna.  相似文献   

19.
陈俊松  赵尘  石迪 《森林工程》2010,26(5):83-86
为比较人工林的不同林分在不同林龄下的经济效益,依据与当地林业生产企业的资料和数据,采用净现值法、内部收益率法等经济分析方法,分别对不同龄级的杉木、马尾松和桉树人工林的动态收益进行分析,并对工资水平、成本、税费、木材产量和价格进行敏感性分析。研究结果表明:各种林分和龄级人工林的净现值均大于零;桉树林的内部收益率最高,木材产量和价格对经济效益的影响最为明显。  相似文献   

20.
A stand dynamic model was developed to predict the growth response in even-aged forest plantations of different initial planting densities. The model is based on the integration of three subcomponents: height growth, self-thinning, and diameter increment. The integrated model uses the height of dominant trees to simulate stand response to site quality and internal growth potential. An extended self-thinning submodel is used to simulate mortality in stands due to crowding and inter-tree competition. A diameter increment submodel is used to link the height growth and self-thinning submodels. The height growth submodel is based on an application of the “Pipe Model” theory. The three-parameter self-thinning submodel is developed from an extended self-thinning law that captures self-thinning in stands before they attain full stocking. The diameter increment model is based on the assumption that diameter increment is related to height growth and available growing space described by stand density. The integrated model is applied to data collected from a 45-year-old red pine (Pinus resinosa Ait.) plantation subsectioned with different initial planting densities. For the data used, only two parameters were required to capture 99% of measured variation in height growth. Additional data from sites with different planting intensities are required to formulate a more generalized height growth model. The slope of the linear self-thinning limit for red pine is approximately −1.5. Model predictions are consistent with field measurements.  相似文献   

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