白云机场飞行区土壤综合治理与植被恢复研究

本文通过对白云机场飞行区土壤酸化情况调查、机场土壤实地改良研究，分析现有的植物种类，并针对酸性土壤改良区适宜植物种类，基于施工难度和景观效果，提出土壤改良与植被修复措施。     

Characterization of the morphological,physical, and mechanical properties of seven nonwood plant fiber bundles

The morphological, physical, and mechanical properties of the nonwood plant fiber bundles of ramie, pineapple, sansevieria, kenaf, abaca, sisal, and coconut fiber bundles were investigated. All fibers except those of coconut fiber had noncircular cross-sectional shapes. The crosssectional area of the fiber bundles was evaluated by an improved method using scanning electron microscope images. The coefficient factor defined as the ratio of the cross-sectional area determined by diameter measurement, to the cross-sectional area determined by image analysis was between 0.92 and 0.96 for all fibers. This indicated that the area determined by diameter measurement was available. The densities of the fiber bundles decreased with increasing diameters. The diameters of each fiber species had small variation of around 3.4%-9.8% within a specimen. The tensile strength and Young’s modulus of ramie, pineapple, and sansevieria fiber bundles showed excellent values in comparison with the other fibers. The tensile strength and Young’s modulus showed a decreasing trend with increasing diameter of fiber bundles.     

不同施肥措施对3年生山桂花人工林林木生长的影响

在云南省的孟连县开展营造山桂花人工林施用N、P、NP、NPK肥及其每种植穴用量为0 g、100 g、200g、300 g的不同施肥措施对3年生期间山桂花人工林林木生长影响的试验研究。试验结果表明,当3年生时山桂花人工林林木的材积不同施肥处理的比不施肥处理的高1.6~5.4倍。所施用的4种肥料相比较,施肥效果为:N>NP>NPK>P。其3年生山桂花人工林林木平均材积,施用N的比施用NP的高2.7%,施用NP的比施用NPK的高49.3%,施用NPK的比施用P的高191.8%。不同施肥量对山桂花人工林(3年生)林木生长的效应是P300 g>200 g>100 g>0 g;N和NP是200 g>300 g>100 g>0 g;NPK是300 g>100 g>200 g>0 g。受当地气候影响,山桂花人工林(3年生)的生长可分为两季,12月~次年5月处于旱季,因气温低,降水少其幼林生长慢,6~11月为雨季,气温高、降水足其幼林生长快,雨季生长量比旱季高50%以上。     

定向苗木概念

定向苗木概念在评价更新造林和恢复造林中是个相对新而有效的方式。它强调苗木质量必须在造林地进行测定,而且不存在通用型优良苗木。特别是,定向苗木概念强调成功的造林项目需要苗圃经理和客户之间良好的沟通。定向苗木概念可以看做一个循环的反馈体系,从造林地反馈的信息来明确和细化适合每个造林项目的最佳苗木类型。     

北京市城区公园植物多样性及近自然群落的应用

为了掌握北京市建成区公园植物多样性及近自然群落情况,进而为北京城市绿化提供科学基础,对北京市五环内的公园进行了抽样调查和分析.在靠近市中心的很多公园中,我们发现,应用最多的是乔木+灌木,乔木+草坪或少量乔木+少量灌木+草坪型群落结构,近自然化程度较差.本文指出在城市公园建设中应以自然植被和群落演替的基本理论为依据,选择乡土树种即当地自然植被中的主要乔、灌木种类,"模拟自然"的技术和方法通过人工营造与植被自然生长的完美结合,建造以乔木为主体,乔灌花草多种植物相结合、常绿落叶相结合的近自然群落.     

Vertical and leaf-age-related variations of nonstructural carbohydrates in two alpine timberline species, southeastern Tibetan Plateau

Spatial pattern of nonstructural carbohydrates (NSC) was analyzed in two alpine timberline species (Abies georgei and Juniperus saltuaria) growing at the timberline in Sergyemla Mountain, southeastern Tibetan Plateau. We aimed to examine the effect of canopy height and leaf age on balance between carbon uptake and consumption of timberline tree species in extremely environmental condition. The results showed that no significantly vertical variation in sugars, starch or NSC (soluble sugars plus starch) in A. georgei was found for any aged needles. Also, there were no significant differences among vertical gradients in both current and last-year leaves for J. saltuaria. However, different-aged needles/leaves showed significant differences in NSC concentrations in both A. georgei and J. saltuaria. For A. georgei, needle mean NSC across vertical canopies showed a significant increase from current-year to 2-year needles (P < 0.05), followed by a gradual decrease from 2- to 5-year needles (P < 0.05), whereas for J. saltuaria, last-year leaves had significant higher NSC except sugars compared with current-year leaves across canopies (P < 0.01). The observed trends of NSC along vertical canopy heights and leaf ages suggested that, in extreme environmental condition, not only light-induced carbon acquisition in photosynthesis but also carbohydrate export from leaves should be taken into account to explain the spatial pattern of NSC.     

贵州省平坝县斑苦竹种群结构初探

采用样方法对贵州平坝县十字乡自然生长的斑苦竹种群结构特征进行调查分析,结果表明:斑苦竹种群年龄结构中Ⅱ龄级所占比例最大,达到27.9%,其次为Ⅰ龄级和Ⅲ龄级,占调查总数的比例分别为25.1%、20.0%;胸径主要分布在31～45 mm;高度主要分布在6.0～8.9 m,占总体的57.8%。各龄级植株的径级、高度级存在一定差异。随着龄级的增加,胸径变小,说明斑苦竹种群存在衰退的趋势。     

顶果木对锰毒害的响应及解毒研究

研究顶果木苗木在锰胁迫下的生长与生理特性及锰毒害后的恢复方法。结果表明,锰胁迫对苗木地径生长影响不大;苗高生长量随锰胁迫加剧,从9.3 cm递减到7.4 cm。随着锰毒害程度增加,顶果木叶片细胞膜透性、MDA含量也增加,锰0.6%处理时分别为18.23%、22.30μmol.g-1;SOD酶活性呈先提高后降低的趋势,最高为锰0.4%处理的252.24 U.g-1.h-1,锰0.2%以下处理的SOD酶活性低于空白对照(232.49 U.g-1.h-1);叶绿素含量随着锰浓度的提高而递减,并伴随黄化、落叶现象。锰0.4%以下的胁迫处理可以通过浇施磷肥得以缓解锰毒,促进苗木生长;但锰增加到0.6%时,浇施石灰的解毒效果最好。     

不同育苗基质对团花苗木生长的影响研究

开展11种育苗基质对团花苗木生长的影响试验研究,定期对苗木高、地径,地上部分及地下部分的生物量进行测定与分析。结果表明,团花苗木在育苗基质k-2和基质k-9中生长效果最好,在苗木培育过程中,后期生长缓慢有利于苗木的充分木质化,提高造林成活率。咖啡壳作为团花的育苗基质是可行的。     

植物内生菌对柑橘溃疡病的生物防治作用及应用前景

从植物内生菌的抗病机理及生物防治病害作用方面综述了利用植物内生菌防治柑橘溃疡病的机理与优势,并对其生物防治应用前景进行了展望。