昆嵛山林区赤松赤枯病病基指数模型

【目的】构建赤松赤枯病病基指数(Disease based index,DBI)评价体系,定量评价与林分因子共同作用后,立地因子对赤松纯林中赤枯病发生程度的作用等级。【方法】在林龄相对一致(34±2)年的赤松纯林生态系统中设立临时样地,筛选影响赤松赤枯病发生的关键林分因子,建立关键林分因子与赤枯病病情指数的函数关系,选取最优模型作为主曲线;将主曲线等比值拉伸得赤枯病病基指数曲线群,其自下而上依次表示不同的病基指数,即立地对赤枯病发生程度的作用等级。【结果】1)基于森林病害发生的基本原理,提出病基指数的概念。2)确定赤松赤枯病病基指数的定量方法,它包含样地的设立、病情指数的调查、林分因子的调查、关键林分因子的筛选、基准点的确定、备选主曲线模型的建立、主曲线模型的确定和评价、主曲线的绘制及曲线群的建立共9个步骤。3)逐步回归分析表明,林分密度是影响赤松赤枯病发生的关键林分因子,依据所提定量方法建立主曲线方程:Q=65. 61/(1+e-0. 001 5 x+2. 32),决定系数R2=0. 519 8,说明拟合方程较可靠,用该模型预估赤松赤枯病的病情指数时,平均预估误差是5. 35%。4)将赤枯病病基指数主曲线等比值拉伸得曲线群,即建立定量评价体系。体系中的5条曲线自下而上分别表示为:Ⅰ为极轻病害发生,Ⅱ为轻度病害发生,Ⅲ为中度病害发生,Ⅳ为重度病害发生,Ⅴ为特重度病害发生。【结论】赤松赤枯病病基指数主曲线模型和曲线群图可以定量评价赤松林的立地因子对赤枯病的潜在发生程度的作用等级,可为赤松纯林合理、有效的管理提供理论基础,将成为森林有害生物生态控制方法的重要组成部分。     

樟子松赤枯病病原菌研究

以4个地区采集到的樟子松赤枯病标本为材料,采用单孢分离法对病原菌进行了分离、纯化,得到2株真菌为PYJ12、TYJ13,经室内致病性接种试验证明TYJ13为樟子松赤枯病的致病菌。运用病原菌形态学和分子生物学相结合的方法,对樟子松赤枯病的病原菌TYJ13进行了鉴定,其病原菌为柠檬拟盘多毛孢,并对该病害的症状和病原菌形态进行了详细描述。该菌株接种当年生的樟子松针叶没有成功,2-3年生的针叶大量感病,说明该种病原菌寄生性较弱。本文首次确定了引起樟子松赤枯病的病原真菌。     

粤北地区杉木真菌性病害种类

对粤北地区 ( 小坑林场、龙山林场、大坑山林场 ) 杉木（Cunninghamia lanceolate）真菌性病害进行全面调查,共采集 86 份标本,分离病组织获得菌株 162 份,主要归属于炭疽菌属（Colletotrichum）、拟盘多毛孢属（Pestalotiopsis）、腐皮壳属（Diaporthe）、镰刀菌属（Fusarium）、黑孢菌属（Nigrospora）、拟茎点霉属（Phomopsis）、叶点霉属（Phyllosticta）以及散斑壳属（Lophodermium）等。根据病害症状粤北地区主要杉木病害包括：杉木立枯病、杉木炭疽病、杉木溃疡病、杉木顶枯病、杉木梢枯病、杉木赤枯病、杉木球果坏死。各林场杉木林中,杉木炭疽病普遍发生、分布广;种子园中杉木球果病害危害严重,直接影响球果的产量和质量;在大坑山林场 4-5 年生的林分中,杉木顶枯病大面积发生,但在其它地区少有发生;此外,杉木溃疡病、杉木赤枯病和杉木立枯病在个别无性系或者苗圃中零星发生,但危害较轻。     

水杉赤枯病的发生及防治技术探索初报

水杉赤枯病cerospora sequciae EII．etEV．是水杉Metasequoia glyptostroboides Huetcheng树木的1种真菌性主要病害。在武汉市水杉赤枯病发生较为普遍,一般造成水杉叶片脱落,树木早衰,病情逐年有明显的加重和个别地方开始死树,严重影响景观效果,并给我市水杉林地的健康生长及林业生产造成严重威胁。近年来,在市、区林业部门的高度重视下,水杉赤枯病的发生及危害得到了一定的控制,但在局部地段仍有发生,有的地段较为严重,在我区京珠高速公路、107国道、市外环线等地的2侧和部分绿化林发病较重,病情呈上升趋势,一些公路和沟渠2侧尤为严重。     

昆嵛山赤松纯林赤枯病特征及与林分因子的关系

【目的】解析和定量评价林分因子对赤松赤枯病发生(发病率和病情指数)的影响,为昆嵛山赤松纯林的营林措施和赤枯病的预防提供理论指导。【方法】在昆嵛山区域选取林龄相对一致(约34年)的赤松纯林为研究对象,调查林分密度、郁闭度、树高、枝下高、胸径和冠幅6个林分因子及赤枯病的发病率和病情指数,采用方差分析、相关性分析和多重比较分析各项林分因子与赤松赤枯病之间的关系,并通过冗余分析得影响赤枯病发生的关键因子。【结果】赤枯病在赤松林中普遍发生,发病样地占调查样地的96.3%。整体上,高密度林( 2 956 ~4 089株·hm -2 )的发病率和病情指数显著高于低密度林(688~1 822株·hm -2 )和中密度林(1 823~2 955株·hm -2 )的发病率和病情指数;疏林(郁闭度<30%)的发病率和病情指数显著低于中疏林(郁闭度30%~70%)和密林(郁闭度> 70%)的发病率和病情指数;在不同的树高、枝下高、冠幅和胸径分组中,发病率和病情指数均随着分组值的增大而减小。相关性分析表明:林分密度对赤枯病发病率和病情指数的影响均达到极显著正相关水平( r =0.761, P < 0.01;r =0.748, P < 0.01);赤枯病的发病率和病情指数也均受到郁闭度的极显著影响( r =0.509, P < 0.01;r =0.442, P < 0.01);二者与树高均呈极显著正相关( r =-0.443, P < 0.01;r =-0.362, P < 0.01);赤枯病的发病率和病情指数均随枝下高的增大而极显著减小( r =-0.460, P < 0.01;r =-0.419, P < 0.01);二者与胸径均呈负相关关系,且相关性极显著( r =-0.425, P < 0.01;r =-0.373, P < 0.01);随着冠幅的增大,林木发病率和病情指数均极显著降低( r =-0.345, P < 0.01;r =-0.381, P < 0.01)。冗余分析证明林分密度和枝下高对赤枯病发生的贡献最大。【结论】松赤枯病在昆嵛山区域发生较普遍但不严重,其发病率和病情指数在不同林分因子分组中均有差异,且均受各林分因子极显著影响。RDA分析证明,林分密度和枝下高对松赤枯病影响最显著,建议对昆嵛山区域赤松纯林赤枯病的防治工作要以重要因子为主要调控对象,进行合理修剪和间伐。     

陕西华山松病害调查及其发生概述

本文调查了陕西华山松病害种类和发生程度，提出了病害名录，阐述了病害发生概况，并着重介绍了华山松赤枯病等7种病害的症状、病原和发生特点。     

粤北林业有害生物调查

为了解粤北地区林业有害生物发生动态以及危害状况,采用踏查和标准地调查相结合的方法,主要在粤北四县对林业有害生物的发生危害现状进行了调查,基本摸清了粤北林业有害生物常发种类、寄主植物、分布地点、发生面积、危害严重程度等,并对主要有害生物的未来发生风险进行了评估。通过普查,粤北地区常见的病虫及外来有害生物达112种,其中病害51种,昆虫57种,外来有害生物4种。其中危害范围大,程度较为严重的有15种,如松材线虫病、松墨天牛、马尾松毛虫,马尾松赤枯病、杉木枯梢病等。其中在仁化县红山镇新竹村发现毛竹枯梢病,大面积的毛竹已经完全枯死,翁源县全县毛竹枯梢病发生较严重,病害率高达90%以上。主要经济树种杉木受病虫危害较为明显,全县均表现出不同程度的受害症状。乐昌市今年首次发现松材线虫病。通过调查,为今后制定合理的粤北林业有害生物治理方案,更加有效地控制林业有害生物提供科学依据。     

永泰县世行项目造林地幼林病虫害调查

调查表明：在永泰县世行项目造林地上幼林病虫害发生面积达２０３ｈｍ２；害虫有蕉艺夜蛾、微红梢斑螟等９种，病害有松枯梢病、赤枯病等５种，以微红梢斑螟和松枯梢病为害较严重；集中成片、速生快长的单纯针叶林是造林地幼林病虫害发生严重的主要因素。     

杉木苗期赤枯病的发生规律与防治

杉木幼苗期赤枯病（Pestalotia sp．,Robillarda sp．）又名尖枯病,是杉木苗培育中重要病害之一。该病在有利发病条件下,病情蔓延极速,2d之内即暴发成灾,严重侵害的杉木苗很快出现成片或成块坏死,感病植株呈赤褐色或紫褐色,形同火烧水烫一般。泾县白华林场近年来因赤枯病的严重发生而使杉木苗木生产遭受到较大损失。     

云南松赤枯病、落针病的防治试验

1958年以来,在西昌、凉山地区飞播造林90万亩,现已成林50万亩。但病虫害普遍发生、尤其是针叶病害,严重影响云南松林木生长。为了确保飞播成果,促进幼林成长,在我场杉木工区,对云南松赤枯病、落针病进行防治试验。杉木工区地处凉山昭觉县,海拔2200—3400米高,林分组成为云南松、高山     

Seasonal changes in shoot water relations of Picea rubens at two high elevation sites in the Smoky Mountains

Seasonal changes in water relations of current-year shoots of red spruce (Picea rubens Sarg.) were examined in relation to climatic conditions in trees growing at elevations of 1720 and 1935 m on Clingman's Dome, Tennessee, USA, where increment core data have shown that red spruce decline increases with elevation. Relative height growth of trees at 1720 m was 68% greater than in trees at 1935 m. Following two weeks in July with only traces of precipitation, trees at both sites showed decreased saturated osmotic potentials. The magnitude of the reduction was greater in trees at the high elevation site than in trees at the low elevation site. However, during August and September, shoot water relations of trees at both sites were similar. Precipitation patterns and water relations measurements suggested that, at both sites, trees experienced water stress only briefly during the growing season and to a degree that could not account for the lower growth rates of trees at the high elevation site. During the period of cold hardening in October and November, trees at the low elevation site exhibited saturated osmotic potentials that were lower by 0.2 MPa and solute accumulation (osmol kg(dw) (-1)) that was 48% greater than in trees at the high elevation site.     

枣疯病的研究现状

枣疯病是枣树的毁灭性病害,在我省陕北、关中等枣区有日趋严重之势。该病症状为萎黄丛生及花、叶畸形,其病原为类茵原体(MLO)。除可通过嫁接传病外,中华拟菱纹叶蝉、凹缘菱纹叶蝉和红闪小叶蝉是三种重要的传病媒介昆虫。枣疯病的发生还与枣树的品种、枣园的土壤、海拔、坡向等有关。枣疯病的防治途径有药物治疗、砍疯枝、铲病株、热处理脱毒等,但以培育抗病品种、选育无病苗木和加强栽培管理、增强树势为其根本的防治措施。     

Elevation patterns of woody taxa richness in the evergreen Afromontane vegetation of Ethiopia

Plant species distributions show patterns along elevation gradients. Regardless of the diverse Afromontane vegetation in Ethiopia(AFE), studies of elevation patterns of woody plants are limited and they are restricted to small areas or single/few Mountains. Moreover, there is no general consensus on the patterns of woody taxa distribution by elevation. The objectives of this study were to examine the elevation patterns of woody taxa richness and their relationship with elevation in the AFE. Data were collected and compiled from the Flora of Ethiopia and Eritrea(Vols. 1–7). About 5918 plant species of 243 families were examined and their elevational distributions were recorded. The distributional ranges of woody taxa were aggregated at 19 points(sites) at 100 m intervals starting from 1500 to 3400 m a.s.l. Single-factor analysis of variance(one-way ANOVA) was used to test the hypothesis that mean species richness of woody taxa decreases from the lower to the upper limit of AFE. Simple linear correlation and regression were used to show the relationships of woody taxa richness with elevation. We documented the presence of 505 woody taxa(441 species,31 subspecies and 33 varieties) representing 267 genera and 90 families in the AFE. In terms of habit, 279 taxa are shrubs, 178 are trees and 48 are lianas. The distribution of woody taxa(trees, shrubs and lianas) showed a slight increase at the lower portion and a monotonic decline with increasing elevation. Species richness of trees, shrubs and lianas was negatively and significantly correlated with elevation(r =-0.985,-0.984,-0.981, respectively; all p 0.001). Our hypothesis was accepted because mean richness significantly decreased from the lower to the upper limit of AFE(p 0.001). Generally, monotonic patterns of decline in richness were observed for trees, shrubs and lianas. The contribution of shrubs to total richness increased with increasing elevation whereas that of trees and lianas decreased.     

天宝岩天然猴头杜鹃种群立木级结构特征研究

在对天宝岩国家级自然保护区不同海拔天然猴头杜鹃林乔木种群全面调查基础上,对猴头杜鹃林进行立木分级,采用动态可比性林木分级法研究了猴头杜鹃林种群结构。研究结果表明：不同海拔天然猴头杜鹃林均以Ⅳ级木占绝对优势,该级林木株数远远大于其他级林木数量。此外,各海拔天然猴头杜鹃林Ⅳ级木数量呈现高〉低〉中,而其在相应海拔所占比例却与海拔呈正相关;低海拔天然猴头杜鹃种群处在A型种群的前中期,中海拔种群处在A型种群的后期,高海拔天然猴头杜鹃种群则处在A型种群的中后期。     

影响湿地松粉蚧种群密度因子的初步研究

影响湿地松粉蚧种群密度因子的初步研究＊顾茂彬陈佩珍关键词湿地松粉蚧、种群密度、环境因子湿地松粉蚧（ＯｒａｃｅｌａａｃｕｔａＦｅｒｉｓ）［１］于１９８８年由美国传入广东省台山市红岭种子园后，迅速繁殖并向四周扩散，目前此虫已分布到开平、新会、恩平、鹤山、...     

阿坝州花椒蛀干害虫调查研究

对阿坝州花椒人工林蛀干害虫进行了较全面的调查.结果表明：阿坝州椒树受蛀干害虫危害严重,平均危害率85.2％,全州椒树平均寿命不超过8年.蛀干害虫种类复杂,主要有嫩枝天牛、虎斑天牛、台湾狭天牛、椒树长足象鼻虫等.随着海拔的不同,蛀干害虫的分布有较大差异.低海拔区以嫩枝天牛、椒树长足象鼻虫为主,高海拔区则以虎斑天牛、台湾狭天牛为主.     

Aboveground net primary productivity of a beech (Fagus moesiaca) forest: a case study of Naousa forest, northern Greece

Based on allometric relationships and information provided in forest management plans, we determined aboveground net primary productivity (ANPP) for a 10-year period in a Mediterranean beech forest (Fagus moesiaca Cz.) extending across an elevation gradient. The ANPP ranged from 1.87 to 15.71 Mg ha(-1) year(-1), and leaf area index (L*) ranged from 2.3 to 3.6. Although small trees (diameter at breast height < 10 cm) were not sampled, it was unlikely that this accounted for the low L* because there were very few small trees on a per-hectare basis. A weak positive relationship was found between ANPP and L*, and only ANPP was negatively related to elevation. Although L* did not vary with elevation, biomass growth efficiency (ANPP/L*) declined strongly with elevation. Leaf carbon isotope composition, leaf nitrogen content per unit area and specific leaf area of leaves collected from nine trees across an elevation gradient all varied significantly with elevation and were significantly related to one other, suggesting that water limitations at higher elevations may have driven the reduced growth efficiency at the stand level. Strong winds may also have negatively affected ANPP at higher elevations by altering belowground allocation. Further research is needed to test these hypotheses and to determine the belowground dynamics of phytomass in this ecosystem.     

Fungal root pathogen (<Emphasis Type="Italic">Heterobasidion parviporum</Emphasis>) increases drought stress in Norway spruce stand at low elevation in the Alps

Tree-ring patterns of Picea abies (L.) Karst. both unaffected and affected by Heterobasidion parviporum were analysed in three mature stands located at different elevations in the Eastern Alps. The main objectives were (1) to clarify the role of climatic conditions on infected trees; (2) to estimate indirect volume losses due to the prolonged presence of the fungus within the wood. The low elevation site showed the highest growth decline in the last decade, whereas all infected trees at medium and high elevation showed a slow growth decline over many decades. We hypothesise that infection could be dated over 80 years at the highest site. Fungal attack made P. abies more susceptible to drought stress at low elevation site. Both infected and healthy P. abies at medium and high elevation showed similar climate–growth relationships, suggesting that the same driving environmental factors influence their growth. At low elevation, H. parviporum was seemingly more aggressive, causing a more rapid decline, decreasing the ability of host trees to cope with drought and, in some cases, inducing cambial activity to stop. P. abies at higher elevation, however, exhibited a very slow decline and no sign of increasing water stress since the influence of climate on tree growth was the same for both infected and healthy trees.     

Beobachtungen über das Auftreten vonThaumetopoea wilkinsoni Tams. (Lep. Notodontidae) auf Zypern

Summary The processionary caterpillar occurs all over lyprus up to an elevation of about 4500 ft. The flight season is in the summer (July, August). The eggs are usually laid of pine neddles, but occasionally they are laid under the bark. The eggs hatch sometime in the autumn (Sept. Oct.), depending on weather conditions. The young larvae begin weaving their characteristic nests on the branches and needles. After emergence by the end of March, or the beginning of April, the mature Caterpillar goes to the soil for pupation, where they remain until the end of June or the beginning of July. They attack most pines but in particularPinus brutia. The control measure, is the cutting away of the nests, burning them or spraying the effected trees with 50% DDT.     

Forest structure, diversity and regeneration in unburnt and burnt Anogeissus latifolia forests in Garhwal Himalayas

The present study was carried out at two different gradients of unburnt and burnt Anogeissus latifolia forest sites in the Garhwal region, India. At each gradient, the unburnt and burnt forest sites were further categorized into three different elevations, i.e., lower (700 m), middle (850 m) and upper (1000 m). At each elevation, the density of trees, saplings and seedlings was higher at the unburnt sites except for trees at the upper elevation which was higher at the burnt sites. The total basal area of each layer of forest was also higher at the unburnt sites. The study revealed that the lower number of saplings and seedlings at the burnt forest sites might be due to the effect of fire. Most trees in the lower dbh classes were affected by forest fire at the burnt sites which reduced the total density and total basal area of the trees compared to the unburnt sites. The diversity of trees increased with increasing elevation. However, the diversity of saplings and seedlings reduced with increasing elevation.