侧柏平衡根系无纺布容器苗与塑料袋容器苗造林对比试验

对枣庄市山亭区4个试验点的侧柏应用平衡根系无纺布容器苗造林与塑料袋容器苗造林的对比试验表明:应用平衡根系无纺布容器苗的侧柏造林成活率为98.5%,比塑料袋容器苗造林提高55.4%;与塑料袋容器苗的树高、地径、新梢生长量相比较,分别提高47.8%、39.2%和21.4%;从造林成本来说,平衡根系无纺布容器苗造林比塑料袋苗低。因此,应用平衡根系无纺布容器苗造林是荒山造林的有效技术措施。     

从红松苗木水分状况判断苗木质量的研究

本文探讨了红松苗木水分状况对造林成活率的影响。在造林前利用植物水分状况测定仪及四唑染色法对苗木根系水势和根系脱氢酶活性进行测定,结果表明,苗木造林前大量失水,使根系水分下降,直接影响造林成活率。因此,必须使红松苗的含水率在63%以上,才能保证造林成活。     

杨树插干与带蔸造林生长及根系发育比较

以江汉平原4个杨树主栽品种为试验材料,分别进行插干和带兜造林,比较两种造林方式生长和根系发育差异。结果发现:两种造林方式,生长差异显著,插干造林具有明显的生长优势。进一步对两种造林方式根系发育进行比较发现,前期根系发育差异不大,随着时间增长,插干造林的生根数量、根重、生根区间长度等特征都显著大于带兜造林。正是由于插干造林根系发达,分布均匀,吸收根和运输支撑根合理配置,更利于水分、养分的吸收运输,且不易倒伏,最终相比带兜造林表现出显著的生长优势。     

杉木苗根系打浆造林效果试验

杉木苗根系打泥浆后造林不仅能提高造林成活率,而且与当年生幼树的根系地径和树高的生长关系密切,在不同的造林时间或造林后的不同时间,其影响程度是不同的。     

樟子松沙地造林技术综述

樟子松幼树不耐风吹沙打,不能在流动和半流动沙丘或小豆茬、花生茬等撂荒地直接造林。樟子松苗木根系细弱,容易风干,保持苗木根系湿润,是提高造林成活率的关键措施。樟子松按照苗木类型,分为裸根苗造林,容器苗造林和幼树移植造林。     

沙地节水造林新技术-超深栽造林技术

为了提高沙地造林成活率和保存率,该文提出了一种节水造林新技术-沙地林木超深栽造林技术。该技术通过采用林木深根苗(垂直根系长度超过60cm的苗木)或长茎苗(具有较长主茎的苗木),造林时直接将其根系栽植到保有较多水分的下层土壤,使苗木根系能直接吸收到土壤中的水分,不仅能够大大提高造林成活率,且苗木生长亦优于常规技术造林苗木。该文对该技术所采用苗木的快速培育、超深栽造林以及栽后管护等方面进行详细阐述,以期推进林木超深栽造林技术在干旱半干旱沙地造林中的推广应用。     

腾格里沙漠东南缘沙拐枣造林成活率研究

通过对沙拐枣原生苗和扦插条的不同试剂造林处理,研究了沙拐枣造林成活率及生长情况。研究表明:在半固定沙丘采用腐殖酸+纳米液处理的扦插造林效果最好,能够将常规沙漠造林成活率提高40%以上;用腐殖酸+AM菌处理最适合原生苗造林;AM菌促进原生苗的根系和植株生长,抑制扦插条根系的萌发和生长;腐殖酸对沙拐枣的成活和生长有极大促进作用;纳米液对扦插造林的根系生成和植物生长有激发作用。     

“盐水蘸浆”在干旱阳坡造林上的应用试验

<正>盐水和泥浆蘸苗造林,具有提高泥浆的盐度,防止苗木根系水分的外渗透,保存土壤、苗木根系内水分的作用,而且操作方便,造林成本低,可广泛应用于大面积工程造林。     

华北落叶松切根换床苗与留床苗的根系生长与造林效果

对华北落叶松切根换床苗与留床苗的根系与造林效果研究表明,换床苗的根系发达,吸收土壤中水分、养分能力强,造林效果好。用换床苗造林是提高造林成活率和幼林生长的有效途径之一,在太行山绿化中值得推广。     

马尾松在干旱紫色土地区根系处理造林试验

马尾松根系处理造林，可有效地促进根系早发，扩大根系吸收面积，对提高干旱紫色土地区马尾松造林成活率有显著作用，能够有效地促进林木生长。     

Root parameters of forest trees as sensitive indicators of acidifying pollutants: a review of research of Japanese forest trees

The root parameters of forest trees can be indicators of a changing environment. We summarize the results of root studies with regard to the effects of acidifying pollutants, especially soil acidification and aluminum toxicity, on various root parameters of Japanese forest trees under experimentally controlled conditions. All root parameters such as biomass, morphology, nutritional status, and physiology can be regarded as indicators, because, under laboratory conditions, root responses occur prior to the responses in the aboveground parts. However, considering the conditions of forest sites, the nutritional status and physiological changes are better indicators of soil acidification and Al stress than the biomass and morphological response. The currently available data suggest that the most important indicator is the Ca/Al molar ratio in roots of Japanese tree species. In order to predict and detect the initial effects of soil acidification, we postulate that the specific root response to the Ca/Al molar ratio of tree roots should be considered as a parameter for use in long-term forest monitoring sites.     

农田防风林的胁地现象及补救措施

调查分析了挖断根沟前后距林带近和和远处农作物的产量。结果表明：在山西省北部半干旱风沙区，存在着林带胁地的现象，挖断根沟是一项较好的克服胁地影响的措施，能够大幅度地减少因胁地而带来的减产。     

Biomass and carbon pools of disturbed riparian forests

Quantification of carbon pools as affected by forest age/development can facilitate riparian restoration and increase awareness of the potential for forests to sequester global carbon. Riparian forest biomass and carbon pools were quantified for four riparian forests representing different seral stages in the South Carolina Upper Coastal Plain. Three of the riparian forests were recovering from disturbance (thermal pollution), whereas the fourth represents a mature, relatively undisturbed riparian forest. Above and belowground carbon pools were determined from linear transects established perpendicular to the main stream channels and spanning the width of the riparian area. The objective of this study was to quantify the biomass and carbon pools in severely disturbed, early successional bottomland hardwood riparian forests and to compare these values to those of a less disturbed, mature riparian forest.

Aboveground biomass in all four riparian forests increased during the 2.5-year investigation period. The total carbon pool in these South Carolina Coastal Plain riparian forests increased with forest age/development due to greater tree and soil carbon pools. The mature riparian forest stored approximately four times more carbon than the younger stands. The importance of the herbaceous biomass layer and carbon pool declined relative to total aboveground biomass with increasing forest age. As stands grew older fine root biomass increased, but an inverse relationship existed between percentages of fine root biomass to total biomass. The root carbon pool increased with forest age/development due to a combination of greater fine root biomass and higher root percent carbon.

Aboveground net primary production (NPP) in young riparian forests rapidly approached and exceeded NPP of the more mature riparian forest. As a woody overstory became established (after 8–10 years) annual litterfall rate as a function of NPP was independent of forest age and litterfall amount in the young riparian forests was comparable to mature riparian forests. Biomass in the riparian forest floor and carbon pool declined with increasing riparian forest development. Woody debris in these riparian forests comprised a relatively small carbon pool. An understanding of bottomland hardwood riparian forest carbon pools at different stages of succession allows us to assess how time since disturbance influences these pools, leading to a better understanding of the recovery processes.     

基于高分二号的旺业甸林场蓄积量估测模型研究

【目的】为了探究国产高分二号(GF-2)影像在林分蓄积量估测中的潜力,并找到最佳的蓄积量估测模型。【方法】本次实验以内蒙古旺业甸林场为研究区,以高分二号卫星影像为信息源,结合2017年10月份调查的75块样地以及同时期的GF-2影像数据,提取波段特征、植被指数和纹理特征等43个遥感因子作为候选变量,利用Pearson相关系数选择出与蓄积量显著相关的6个变量,采用多元线性回归模型(MLR)、BP-神经网络模型(BP-ANN)、随机森林模型(RF)、支持向量机模型(SVM)和K邻近模型(KNN)进行蓄积量的估测。以决定系数(R^2)、均方根误差(RMSE)、相对均方根误差(RRMSE%)作为5种模型的评价指标,选择出旺业甸林场的最佳蓄积量估测模型,并绘制了研究区的森林蓄积量分布图。【结果】4种机器学习模型的结果明显优于传统的线性模型,其中随机森林(RF)模型和K邻近模型(KNN)均得到了较高的精度,其中RF模型的R^2为0.66,均方根误差为55.2 m^3/hm^2,相对均方根误差为28.1%,KNN模型的R^2为0.64,均方根误差为57.6 m^3/hm^2相对均方根误差为29.3%。【结论】在利用高分二号数据进行旺业甸林场蓄积量估测时,RF和KNN模型在估测针叶林蓄积量时相比于其他模型可以取得更好的结果。     

林分根系分布及其对土壤抗冲性的影响

对各林分根系的分布及对其土壤抗冲性进行了分析,得出各林分根系对土壤抗冲性的增强值随降雨强度的增大而减小,各林分根系对土壤抗冲性的增强值随土层深度的增加而减小,对土壤抗冲性的增强效应依次为毛竹林＞柑桔林＞杉木-南酸枣-木荷混交林＞杉木林.     

台湾西南部优势竹类箣竹根力之研究

箣竹为台湾西南部泥岩地区早期主要造林树种,约占该地区绿蔽率之80%,形成极优势之植物。近年来因竹材价格低落,竹林之经营管理减少,其更新造林及其对坡面之保育功能之评价渐受重视。因此本研究为针对箣竹其根力特性,特进行根系与根域范围调查、根段拉力与植株引拔试验等,推估其坡面保育功效。研究结果为箣竹之根段拉力强度(Y)与其直径(X)成指数正相关,而箣竹之引拔抗力(F)与其胸高直径(D)成指数正相关。     

林木根系分泌物与根际微生物研究进展

对林木根际微域环境的根系分泌物和根际微生物的研究动态进行了综述，重点介绍了根系分泌物与根际微生物的相互作用、根系分泌物与根际效应、根际微生物与林地土壤质量等方面的研究现状。此外，对当前在林木根际微域环境研究中存在的问题进行了简析与展望，并探讨了未来的发展趋势。     

广东沙质海岸防护林前缘植草研究

利用营养坯，以扦插方式在苗圃先行育苗，待形成根系及恢复生长后，再移植至海滩，是营造沙质海岸防护林植草带的有效方法，可以获得９０％以上的成活率。单叶蔓荆子、蔓茎栓果菊和卤地菊是适于南方沙质海滩迎风方向种植的草种。它们具生长快，易生出不定根和萌生新单株，耐淹埋等沙生植物特性。移植１ａ后的盖度分别达到１００％、５３％和４３％（种植规格为１ｍ×１ｍ）。４～８月为生长最迅速时期，平均相对生长速率分别为０．６３５，０．５３５和０．３５７ｇ／（ｇ月）。因此，３～４月是最适移植的季节。     

我国杨树溃疡病研究进展

杨树溃疡病主要由真菌侵染所致,该真菌是一类世界性分布的真菌,寄主范围十分广泛,可危害多种林木和果树的树干及果实,引起枯枝、溃疡、流胶和果腐等。另外,还可以引起根腐,导致整株树的枯死。发生病害的林木,用材林材性降低,经济林产量降低,造成严重危害和经济损失。文中对其病害分布、致病机理、抗病机制以及抗病育种等进行了综述。     

红脂大小蠹生物生态学特性及防治的研究

红脂大小蠹是国内新纪录种，为害油松的主干和主侧根，可导致健康油松在短期内大量死亡。该虫主要以成虫和老熟幼虫越冬，一般1年1代，在较寒冷地区．深层主侧根部位发育速率较慢，3年2代或2年1代，世代重叠。在纯林、生长衰弱、郁闭度小的林分中为害较重。营造混交林、加强林木管理、控制虫源、引进并保护和利用天敌是控制红脂大小蠹的有效措施。