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1.
指出了木麻黄是我国东南沿海防护林的造林先锋树种。石狮市位于福建省东南沿海,市域三面临海,木麻黄防护林有大面积种植。基于现有参考文献和多年从事石狮市林业工作的实践与调查,总结了石狮市沿海木麻黄防护林的主要有害生物种类,并对其的综合防控措施进行了简要阐述。  相似文献   

2.
一、前言木麻黄Casuarina equistifoIia Linn。是海南岛沿海防护林的主要造林树种,现有面积100多万亩,已大片郁闭成林。龙眼蚁舟蛾Stauropus aIternus WaIker属鳞翅目舟蛾科。近年来,发现该虫在文昌县  相似文献   

3.
海南岛沿海地区木麻黄的采伐方式问题   总被引:1,自引:1,他引:0  
前言木麻黄(Casuarina spp.)是我国南方沿海沙滩造林优良的先锋树种。海南岛木麻黄种植面积达135万亩,其中大部分植于沿海沙地。近几年,对早期种植的木麻黄已逐步采伐利用。但是,用什么采伐方式尚缺乏经验,有待进一步试验研究。现根据几年来沿海地区木麻黄的采伐情况谈谈个人的粗浅看法。  相似文献   

4.
木麻黄病害研究概述   总被引:2,自引:1,他引:2  
木麻黄是我国东南沿海防护林的主要树种。文章综述了国内外木麻黄病害研究概况,着重介绍木麻黄青枯病的抗性育种、营林技术、生物和化学防治等方面的具体进展,同时也介绍了木麻黄树干疱腐病、衰退病、白粉病等的研究现状。  相似文献   

5.
中国东南沿海混交海防林建设研究进展   总被引:1,自引:0,他引:1  
综述了我国东南沿海混交海防林的现状,目前混交林型海防林主要是木麻黄与湿地松、相思类树种与桉属等树种混交形成的混交林。通过分析比较不同混交林型的生长效果、防护效能和改土效果,提出合理的混交类型。此外还提出采用乡土树种与木麻黄混交,为建设混交林型的海防林体系提供更多的混交树种选择,为我国沿海防护林的管理、低效林的改造以及提高海防林的生态功能提供参考。  相似文献   

6.
海岸带木麻黄林生态系统过程与可持续管理   总被引:2,自引:0,他引:2  
木麻黄为我国东南沿海防护林体系的主栽树种,如何维持和提高其环境调控功能成为当前沿海防护林经营的重要科学问题。文中概述了海岸带木麻黄林生态系统的物质循环、能量流动和防护功能以及育林措施对森林生态系统的影响等国内外研究成果,指出木麻黄人工林具有生产力高、光能利用率高和适应性强的特点;在探讨干扰与木麻黄林生态系统退化之间关系的基础上,提出加强木麻黄海岸防护林的恢复重建与生态系统管理等建议。  相似文献   

7.
木麻黄是我国东南沿海主要防护树种,由于经营不善造成更新困难、生长衰退、病虫害加剧,严重地影响了防护林的可持续发展。文章从分析影响木麻黄防护林持续经营因素出发,探讨了木麻黄防护林持续经营的途径。  相似文献   

8.
木麻黄害虫星天牛生活习性及防治   总被引:2,自引:0,他引:2       下载免费PDF全文
徐起 《林业科学研究》1997,10(5):551-555
木麻黄害虫星天牛生活习性及防治*徐起关键词木麻黄星天牛生活习性防治近年来,浙江省沿海防护林的主栽树种——木麻黄(CasuarinaequisetifoliaL.)受星天牛(AnoplophorachinensisForster)危害日益严重。据作者对...  相似文献   

9.
沿海木麻黄生态效益研究综述   总被引:2,自引:0,他引:2  
木麻黄是我国东南沿海防护林的主要造林树种,对其生态效益的探讨已成为沿海防护林研究的重点问题。本文选取防风固沙、调节气候、改良土壤、涵养水源等四个生态指标概述木麻黄的生态效应,针对目前木麻黄造林存在的树种结构单一、病虫害发生、二代更新困难等一系列问题,从造林技术着手,提出了沿海防护林恢复重建的对策。  相似文献   

10.
木麻黄青枯病研究概述   总被引:3,自引:0,他引:3  
木麻黄青枯病是我国东南沿海的一种毁灭性林木细菌病害.该文全面回顾了木麻黄青枯病的发生历史,系统介绍了病害的病原、症状、发生条件及流行规律,概述了青枯菌对木麻黄的致病机制、木麻黄的抗性分化和变异、抗性测定、抗病机制的研究进展,以及木麻黄青枯病的控制策略和防治措施,并对未来研究提出了展望.  相似文献   

11.
This study was carried out to assess the relationship of the status of nodulation (i.e., the number of nodules, their shape and size) in root and biomass production of plant growth parameters (i.e., number of leaves, root and shoot lengths, root biomass and shoot biomass) in Albizia saman and Leucaena leucocephala. The assessment started 60 days after seeding. The study revealed that nodulation response and biomass production in both species showed significant dif- ferences over time (p 〈 0.05) in all variables except in the root-shoot ratio (oven-dry) of L. leucocephala. The study also showed significant differences (p 〈 0.05) in nodule formation and biomass production at the end of the study period be- tween the two species except in the number of nodules and leaves and the green root-shoot ratio. There were strong pos- itive correlations between nodule formation and biomass production, i.e., the number of nodules and the age of plants, the number of nodules and leaves, as well as the number of nodules and biomass (root biomass and shoot biomass) in both species. The results obtained using principal component analysis (PCA) and correlation coefficients of the different characteristics of nodulation and biomass production were similar in both species. The PCA showed that shoot biomass (shoot green weight and shoot oven-dry weight) is positively correlated with PC1 (with an eigenvalue of 7.50) and root length is positively correlated with PC2 (with an eigenvalue of 0.19) in the case of A. saman. In the case of L. leucocephala, the PCA revealed that root biomass (root green weight and root oven-dry weight), shoot biomass and shoot length are also positively correlated with PC1, while nodule formation and the number of leaves are positively correlated with PC2 (with an eigenvalue PC1 of 6.92 and PC2 of 0.49).  相似文献   

12.
采用成层掺壤土(T  相似文献   

13.
We excavated soil to study root distribution in Haloxylon ammodendron seedlings grown with different amounts of irrigation (35, 24.5 and 14 kg water for each plant each time) in the hinterland of the Taklimakan Desert. The results indicated that: 1) With decreasing irrigation amounts, the root biomass tended to be distributed in deeper soil layers. Underground biomass had a significantly negative logarithmic relationship with soil depth under different irrigation amounts. 2) Maximum horizontal spread of roots was twice that of vertical root spread, and horizontal distribution of root biomass was similar under all irrigation amounts. 3) Vertical distribution of fine roots was nearly consistent with vertical changes in soil moisture, and all had a unimodal curve; but peak values of fine root biomass in different soil layers varied with different irrigation amounts. The smaller the amount of irrigation, the deeper were the fine roots concentrated in soil layers. 4) Root length, root surface area and root volume all exhibited a unimodal curve under different irrigation amounts; the less the irrigation amount, the deeper the peak values appeared in soil layers. 5) Rootshoot ratio and ratio of vertical root depth to plant height both increased as irrigation amounts decreased. __________ Translated from Journal of Plant Ecology (Chinese Version), 2007, 31 (5): 769–776 [译自: 植物生态学报]  相似文献   

14.
【目的】探明广西不同栽培区江南油杉细根生物量的空间分布共性及其对土壤水分的响应机制。【方法】以广西3个栽培区江南油杉人工幼林为研究对象,采用根系全株分层挖掘和根系形态结构分析法,定量分析江南油杉幼树不同径级细根生物量密度、根长密度和表面积密度的空间分布特征。【结果】1)江南油杉幼林期细根生物量在垂直方向上主要分布在0~90 cm土层中,且0~60 cm范围内的细根生物量占总量的81.83%,细根生物量随土层深度的增加呈升高—降低—再升高的趋势。细根生物量在水平方向上主要分布在距树干0~100 cm范围内,其中0~50 cm细根生物量占总量的87.40%。综合不同径级根长密度和根表面积密度分析结果表明,d <5 mm径级细根是江南油杉幼树占主导地位的吸收根系,其中0.5 mm≤d <2 mm径级细根在不同样地以及不同土层中的根长密度值最大,是决定江南油杉幼树根长密度分布特征的主要根系。2)江南油杉细根总生物量、根系长度、根表面积与土壤水分含量呈显著的相关性,表明江南油杉细根分布对土壤水分含量的响应敏感。【结论】江南油杉细根生物量垂直分布的"双峰"特征有利于根系对表层土壤水分在下渗过程中的二次吸收利用。0~60 cm土层是江南油杉幼树根系发挥生理功能的主要土层,可作为该树种水肥管理的重要区域。  相似文献   

15.
Spatial statistical analyses were performed to describe root distribution and changes in soil strength in a mature clonal plantation of Eucalyptus spp. in the Congo. The objective was to analyze spatial variability in root distribution. Relationships between root distribution, soil strength and the water and nutrient uptake by the stand were also investigated. We studied three, 2.35-m-wide, vertical soil profiles perpendicular to the planting row and at various distances from a representative tree. The soil profiles were divided into 25-cm2 grid cells and the number of roots in each of three diameter classes counted in each grid cell. Two profiles were 2-m deep and the third profile was 5-m deep. There was both vertical and horizontal anisotropy in the distribution of fine roots in the three profiles, with root density decreasing sharply with depth and increasing with distance from the stump. Roots were present in areas with high soil strength values (> 6,000 kPa). There was a close relationship between soil water content and soil strength in this sandy soil. Soil strength increased during the dry season mainly because of water uptake by fine roots. There were large areas with low root density, even in the topsoil. Below a depth of 3 m, fine roots were spatially concentrated and most of the soil volume was not explored by roots. This suggests the presence of drainage channels, resulting from the severe hydrophobicity of the upper soil.  相似文献   

16.
沙地柏对毛乌素沙地3种生境中养分资源的反应   总被引:22,自引:3,他引:22  
为了揭示沙地柏对毛乌素沙地不同生境中养分资源的适应性反应 ,分析了固定沙地、流动沙地和滩地中土壤养分状况、生物量和养分在植株不同结构中的分配以及植株对不同养分的利用和重吸收效率。结果表明 :(1) 3种生境中的氮、磷、钾、钙和镁含量存在不同程度差异 ;(2 )生物量、氮和磷在叶片中分配比率随氮和磷含量的降低而增大 ,而在根中的分配恰好相反 ;(3)氮和磷重吸收效率、钾利用效率和重吸收效率、钙和镁利用效率随相应养分含量的降低而增大 ,氮和磷利用效率随氮和磷可利用性的降低而降低 ;(4)叶片和根系对养分内循环的贡献恰好相反 ;(5 )根分布对不同养分异质性的影响存在差异。  相似文献   

17.
黄泛沙地毛白杨不同整地规格造林试验   总被引:1,自引:0,他引:1  
在黄泛沙地上进行毛白杨不同整地规格造林试验。结果表明:带状、穴状2种整地方式,8种不同整地规格,毛白杨幼林的胸径、树高生长量无明显差异,大规格整地对土壤容重和土壤含水率也无明显影响。但大规格整地显著增加造林成本,以挖60~80cm见方的植树穴为宜。  相似文献   

18.
Acetylene reduction activity by root nodules of the legumeErythrina poeppigiana, growing as shade tree in a Costa Rican coffee plantation, was estimated. The mean activity found was 15.7 nmole C2H4 · mg (dry weight)–1 · h–1. Root nodules collected at different distances from theErythrina stem showed the same activity per dry weight unit. However, as the biomass of the nodules was highest near the stem, was the acetylene reduction activity (expressed per soil volume) maximal near theErythrina stem and declined with distance.  相似文献   

19.
【目的】揭示呼伦贝尔沙区4种生境土壤真菌群落结构与多样性及其影响因素,探究不同生境对土壤真菌的影响。【方法】选择裸沙地、草地、樟子松人工林和樟子松天然林4种生境土壤真菌为研究对象,采用野外调查、ITS高通量测序结合RDA分析,比较分析不同生境土壤真菌种群特征。【结果】呼伦贝尔沙区土壤共检测到真菌5门22纲73目28科257属。其中,裸沙地和草地土壤优势真菌门为子囊菌门,樟子松人工林和天然林中优势真菌门为担子菌门。优势属共31属,裸沙地、樟子松人工林的优势属分别是被孢霉属和丝膜菌属,草地和天然林土壤中的优势属分别为被孢霉属和Archaeorhizomyces、红菇属和Geminibasidium。其中裸沙地和草地、樟子松人工林和天然林的土壤真菌进化分支更为接近。草地土壤真菌物种丰富度和个体数最高,分布最为均匀;裸沙地其次;樟子松天然林和人工林物种丰富度、个体数和多样性指数较低,分布也较为集中。土壤真菌群落分布的主要影响因子是土壤含水量,优势真菌属分布受多种环境因子影响,土壤孔隙度、含水量、有机质分别是被孢霉属、Archaeorhizomyces、丝膜属的主导影响因子,全磷则是红菇属和Geminibasidium的主导影响因子。【结论】呼伦贝尔沙区4种生境土壤真菌主要由子囊菌门和担子菌门组成,其中裸沙地和草地、樟子松人工林和天然林土壤真菌群落结构相似度较高。多类型草本植物使真菌种类增多且分布更为均匀,樟子松在一定程度上降低真菌数量和种类,并使其分布更为集中。不同生境的不同植被可以改变土壤性质,而土壤水分、营养元素及孔隙结构等土壤环境因素会直接影响4种生境土壤优势真菌属的代谢过程和功能特征,因此4种不同生境真菌群落结构及多样性呈显著差异。  相似文献   

20.
马尾松细根与土壤养分含量研究   总被引:3,自引:0,他引:3  
应用根钻法研究黔中12年生马尾松(Pinus massoniana)林下不同层次土壤(0~20 cm和20~40 cm)细根的分布情况及土壤养分含量的分布,并做了相关性分析.结果表明,马尾松细根单位面积生物量、根长密度及比根长在0~20 cm土层明显高于20~40 cm土层,在0~20 cm土层中单位面积根量是20~40 cm土层的3~6倍;土壤中养分含量也随着土壤深度的增加逐渐减少;马尾松根系生物量、根长密度及比根长与土壤中有效性养分存在显著正相关关系;细根生物量、根长密度与马尾松胸径呈显著正相关关系;养分含量对生物量、根长密度的综合影响存在显著线性相关性(R~2=0.903、0.917),土壤养分(0~20 cm、20~40 cm)对马尾松胸径存在显著或极显著线性相关关系(R~2=0.878、0.934),与树高线形相关性不明显.  相似文献   

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