坝竹和小篷竹景观效果及实生苗培育

实地调查了黔北坝竹和黔南小蓬竹天然林景观效果,并进行了引种及实生苗培育试验。结果表明：2个竹种在喀斯特石山地沿岩壁下垂如帘,形态飘逸,颇为美观。坝竹实生苗人工培育1年时,每株苗分蘖11个左右,苗高50 cm左右,培育15个月时苗高74 cm左右;小蓬竹实生苗人工培育1年时,每株苗分蘖7个左右,苗高72 cm左右,培育15个月时苗高77 cm左右。研究结果可为坝竹和小篷竹的边坡绿化及盆栽观赏提供参考。     

3个竹种硫含量季节变化

在福建农林大学百竹园内随机选取3个竹种:歪脚龙竹、坭竹、长叶苦竹,分别于春、夏、秋、冬4个季节对其叶片、主枝、小枝的硫含量进行测定,同时以福州市森林公园相同竹种作为参照。结果表明:竹类植物叶片硫元素含量最高,各竹种之间硫元素含量差异显著;同竹种不同季节的各部位的硫含量均有变化,秋季硫含量最高,夏季最低,较秋季平均减少54.88%;竹类植物对于硫元素的吸收作用较强,叶片硫含量均高于国标的最高值2.0 g.kg-1,且叶片硫含量对环境二氧化硫变化具有指示作用,可以考虑作为硫污染区的绿化植物。     

珍贵的竹子

正俗话说,物以稀为贵。著名中国竹类专家马乃训提出,总面积不足100公顷的、零星分布的竹种为渐危竹种,种群面积不足20公顷的为稀有竹种。按照马乃训的要求,广西的稀有濒危竹种为数不少。广西已知竹类有160余种或变种,其中特有竹种38种。除了毛竹、粉单竹、吊丝竹、麻竹等竹种种植面积较大外,其它竹种多是零星种植。目前,仅在广西零星生长、数量日渐减少的竹种有33种,如小蓬竹、大明山方竹、掌竿竹、澜沧梨藤竹、南丹唐竹、光叶箬竹、东兴黄竹、赤竹、紫孝顺竹等,有些仅发现     

毛竹竹腔富硒施肥对竹笋品质的影响

采用不同配比液态富硒肥对毛竹进行竹腔施肥试验。结果表明:富硒肥中大量元素可明显改善竹笋氨基酸含量,微量元素对改善竹笋品质效果不明显,但增加微量元素可促进竹笋对硒元素的吸收;富硒肥中亚硒酸钠浓度对提高竹笋硒含量影响显著;采用大量元素(A)3、微量元素(B)3、亚硒酸钠(C)3配比的富硒肥对提高竹笋硒含量、改善竹笋品质的效果最佳。     

天目山北部余脉竹类植物区系分析

对天目山脉北部余脉地区进行为期５年的竹类植物调查，并进行分析研究，认为该地区竹类植物区系具有以下几个特征；（１）本区竹类植物区系在“属”级和“种”级上均 热带性质；（２）种类比较丰富，共有竹类７属４０种５变各上８变型，是安徽竹类植物最丰富的地区；（３）以散生竹种为主，全生竹类很少，是刚竹属和短穗竹属的重要分化变异中心；（４）地理成分复杂，东西或南北起源的一些竹种相互渗透交汇，具一定的过渡性特征；（     

四川两种竹材理化性质及纤维形态分析

为有效利用四川的乡土竹种慈竹和绵竹,测定分析了2个竹种的理化性质和纤维形态,并与毛竹及常见的阔叶材和针叶材做了对比。结果表明：1）在化学成分上,2个竹种的抽提物含量均小于毛竹,而介于针叶材和阔叶材之间,2个竹种的综纤维素含量和纤维素含量均高于毛竹,木质素含量与毛竹接近,但灰分含量远高于毛竹、阔叶材和针叶材;2）在物理力学特性上,2个竹种竹材密度略低于毛竹,顺纹抗压强度均明显高于毛竹,且优于强度较高的阔叶材马占相思木,2个竹种的抗弯弹性模量和抗弯强度均明显高于毛竹,抗剪强度与毛竹接近,表明2个竹种力学强度均较大,可以用作结构用竹或建筑用竹;3）在纤维形态上,慈竹和绵竹的平均纤维长度分别为0.63和0.67 mm,均小于毛竹,且纤维长度多为500~1 000和1 000~1 500 μm,2个竹种的纤维长宽比均在45以下,表明慈竹和绵竹均不适于作为造纸原料。     

江西省9个种源方竹笋营养成分分析

方竹是世界著名的笋用竹种,具有较高的开发利用价值,零星分布于江西境内。文中对江西省内9个方竹居群竹笋的还原糖、膳食纤维、锌、硼、硒、钼等成分含量进行分析。结果显示：各种源方竹笋均含有较丰富的还原糖、黄酮和膳食纤维,是较好的健康食品。矿质元素整体上以宜春市万载种源含量较高,各种矿质元素含量水平表现为锌 > 硼 > 钼 > 硒,说明方竹笋是一种较好的高锌食材。     

含硒、锗保健笋培育试验初报

通过对立竹基部竹腔注入亚硒酸钠或锗的溶液后,该竹所生产的竹笋体内硒或锗总量有明显增加,红哺鸡竹、白哺鸡竹、黄杆乌哺鸡竹、雷竹所生产的笋含硒总量平均达到0.64×10-6,相当于陕西省紫阳富硒茶含硒量(平均值为0.65×10-6).其中,竹笋内有机硒的含量为(0.031 ～ 0.234)×10-6;试验表明,不同竹种具有不同的富集硒和锗的能力,应选择适宜的注射溶液浓度和竹子品种,以生产富硒或富锗竹笋,使之符合人体的最佳需要.     

观赏竹新品种引进与快速繁育

竹子作为一种重要的观赏植物深受人们的喜爱。竹子在造园中的应用在我国有着悠久的历史 ,从古到今 ,不乏园林用竹之典范。但长期以来 ,竹子在造园中并未得到广泛应用和重视 ,用于造园的竹 (品 )种十分单调 ,常见的只有紫竹、斑竹、慈孝竹等少数竹 (品 )种。我国竹类植物资源十分丰富 ,堪称竹子王国 ,但目前可大量提供用于园林绿化的观赏价值高的竹种不多。而日本、欧洲、美国均长期引种选育观赏竹种 ,拉丁美洲自然分布有许多观赏价值很高的竹种。引进这些竹种 ,不仅可以为造园提供丰富多彩的素材 ,具有广阔的应用前景 ,也可以大大丰富我国的…     

富硒施肥对毛竹叶片比叶重及色素含量的影响

采用含有大量元素(A)、微量元素(B)和亚硒酸钠(C)等营养元素不同配比的自制液态富硒肥对毛竹林进行竹腔施肥试验,研究富硒施肥对毛竹叶片比叶重及色素含量的影响。结果表明:富硒施肥可提高毛竹叶片比叶重、叶绿素b含量和叶绿素总含量,对叶绿素a和类胡萝卜素含量影响不明显,其中大量元素对毛竹叶片比叶重影响最大,硒元素对毛竹叶绿素b含量和叶绿素总含量影响较显著。采用A1B2C3配方的施肥效果最好。     

High diversity of ectomycorrhizal fungi associated with Arctostaphylos uva-ursi in subalpine and alpine zones: Potential inoculum for afforestation

Arctostaphylos uva-ursi plant associations have long been suggested to be a suitable location for afforestations, but systematic studies on the observed beneficial effect are still missing in Alpine areas. In this study we address the question which ectomycorrhizal (ECM) fungal communities exist in Austrian alpine and subalpine Arctostaphylos habitats, and if they persist in A. uva-ursi stands even hundred of years after disappearance of trees in these areas. The diversity of fungal communities associated with A. uva-ursi was assessed in four study sites (1800–2450 m a.s.l.) in the Central European Alps of Tyrol (Austria). Three approaches were applied: (i) collecting and identifying fungal fruit bodies; (ii) studying the arbutoid mycorrhiza morphotypes of A. uva-ursi; (iii) molecular identification of the most common arbutoid morphotypes. The detected diversity of ECM fungal species was very high (99 taxa), and the occurrence of e.g. Boletus, Cantharellus, Suillus, Tricholoma, Russula spp. in sites that have been treeless for centuries is especially remarkable. Fruit bodies of 82 fungal species were found in association with A. uva-ursi, 63 of them were ECM. Seventy arbutoid morphotypes were detected on 2072 mycorrhized root tips, and 39 taxa of basidiomycete mycobionts were identified with molecular methods. Twelve Cortinarius spp. clearly dominated the mycobiont species richness, followed by nine spp. of Thelephoraceae and four spp. of Boletaceae. Most mycobionts of A. uva-ursi were generalists, but fungal taxa (e.g. Lactarius deterrimus and Suillus spp.) known to be specifically associated with other host plants were also detected. We therefore consider A. uva-ursi as a “non-selective” host, providing mycorrhizal inoculum of highly specialized and effective mycorrhizal fungi for afforestation. This explains why A. uva-ursi plant associations represent suitable locations for forest regeneration and afforestation, especially in the harsh environmental conditions of subalpine and alpine sites.     

大娄山区金佛山方竹种子营养成分与播种育苗

调查了大娄山区金佛山方竹的开花结实历程,并采集8个不同地点的金佛山方竹种子分析其营养成分,同时进行种子育苗试验。结果显示：1）大娄山区金佛山方竹在11月前后产生花枝,翌年2月初至3月中旬开花,4月中旬至5月初种子成熟;2）鲜种子千粒质量为230.9~342.5 g,种子含有丰富的蛋白质、脂肪、多糖、碳水化合物、多种氨基酸和矿质元素;3）种子成熟后不耐储藏,40 d后便失去发芽力,种子育苗应随采随播;4）人工异地播种其苗木质量优于原生林落种形成的苗木质量。     

The regeneration characteristics of Picea jezoensis and Abies sachalinensis on cut stumps in the sub-boreal forests of Hokkaido Tokyo University Forest

The regeneration characteristics of Picea jezoensis Carr. and Abies sachalinensis Masters on cut stumps in natural forest under selection cutting and natural regeneration were studied in a sub-boreal forest of the Hokkaido Tokyo University Forest. The following points were investigated: (1) what decay class of cut stumps are suitable for regeneration of the two conifer species; (2) what part, either a root collar or a cut surface, of a cut stump is suitable for regeneration; and (3) what percentages of cut stumps support conifer seedlings. The percentages of cut stumps that supported conifer seedlings increased as the decay class advanced, but slightly decreased in the latest stage of decay class, V. Both P. jezoensis and A. sachalinensis seedling densities per cut stump and per square meter of cut stumps increased as the decay class advanced. Some root collars in decay class IV supported A. sachalinensis seedlings, but few supported P. jezoensis. Densities of P. jezoensis per cut surface and per square meter of cut surface in decay class IV were higher than those of A. sachalinensis. On the other hand, densities of A. sachalinensis per root collar and per square meter of root collar in decay class IV were higher than those of P. jezoensis. Cut stumps in advanced decay classes are more suitable for regeneration of P. jezoensis and A. sachalinensis than those in early decay classes. Whereas a cut surface is more suitable for regeneration of P. jezoensis, a root collar is more suitable for regeneration of A. sachalinensis. Cut stumps are not sufficient to ensure enough conifer regeneration because not all conifer cut stumps in advanced decay classes support conifer seedlings.     

Fruit infestation of Acacia tortilis (Forsk) hyne by Bruchidius andrewesi Pic. (Coleoptera: Bruchidae) in the Thar desert

Bruchidius andrewesi Pic. has been recorded as a serious pest of pods and seeds of Acacia tortilis in the Thar desert of India. Pest infestation on developing pods and its relationship with morphological traits is reported. Pod infestation varied from 5 to 19% with 5–29% infestation of seeds. Infestation of pods is directly related to infestation of seed (r = 0.72^**), and both pod and seed infestation are also directly correlated with loss in seed biomass (r = 0.79^** and R = 0.88^**). The infestation of pods starts in November and increases steady until harvest. Seeds kept in the laboratory for further studies were found to be 100% infested with B. andrewesi, as the insect multiplied faster under these conditions. The heavy infestation is damaging not only to A. tortilis but also to other leguminous trees of the desert. Bruchidius andrewesi has also been found on pods and seeds of Prosopis cineraria, an important indigenous tree of the region.     

Survival and growth responses of Populus nigra, Salix elaeagnos and Alnus incana cuttings to varying levels of hydric stress

The Salicaceae and Betulaceae are important plant families within riparian ecosystems throughout the Northern hemisphere, and cuttings of species within these families are often used in riparian restoration projects due to their capacity for vegetative (asexual) propagation and rapid growth. Riparian zones can experience a wide range of hydrological conditions and establishing cuttings may be subjected to substantially varying levels of hydric stress from inundation and drought. Tolerance to such stress can vary notably between species, and the absence of knowledge of species-specific responses to inundation and drought has resulted in high mortality in many riparian restoration projects. In this paper, the survival and growth responses of Salix elaeagnos (Salicaceae), Populus nigra (Salicaceae) and Alnus incana (Betulaceae) cuttings in relation to varying rates of water table decline and periods of inundation were investigated using rhizopods during a 69-day greenhouse experiment, in substrates of contrasting sediments (sand versus gravel).

Each species responded differently to the experimental treatments. S. elaeagnos demonstrated an ability to establish in stable, declining and inundated conditions by the production of relatively substantial root and shoot biomass in all treatments, along with elongated roots when experiencing water table decline. P. nigra showed high mortality and poor root and shoot production in inundation treatments, suggesting that this species is intolerant to reduced oxygen conditions. A. incana displayed complete mortality in all gravel-based treatments and high mortality or poor growth in the sand-based inundation treatments. All species showed preferences for stable conditions without inundation, along with slow water table decline for S. elaeagnos. Fast rates of water table decline were detrimental to all species. Overall, sand was a much more effective substrate than gravel for supporting cutting establishment. These results suggest that riparian restoration schemes utilizing S. elaeagnos cuttings may experience greater success than those using the other species investigated. P. nigra cuttings may establish more easily if situated where inundation does not occur often or for prolonged periods, and A. incana cuttings should be planted only where very stable conditions dominate. The study highlights the inter-species variability in the survival and growth response of riparian trees to differing hydrological conditions.     

Growth potential of twelve Acacia species on acid soils in Hawaii

Reforestation of degraded tropical sites is often hampered by soils of high acidity, high aluminum saturation, and low fertility. To evaluate the possibility of cultivating Acacia species on such soils, a study was conducted at Waiawa, HI, to test growth under conditions of (1) high acidity (primarily aluminum) and nutrient stress, and (2) no acidity stress and high nutrient availability. Twelve Acacia species, including the important native Hawaiian species Acacia koa, were established on a Ustic Kanhaplohumult soil. The experimental design was a split plot with two fertility treatments as the main plots and the 12 Acacia species as subplots. The treatments were: low fertility (F₀; 143 kg ha⁻¹ 14-14-14 plus micronutrients) and high fertility (F₁; 8 Mg ha⁻¹ lime, 143 kg ha⁻¹ 14-14-14 plus micronutrients, 200 kg P ha⁻¹, and 77 kg K ha⁻¹). Acacia angustissima, Acacia aulacocarpa, Acacia auriculiformis, Acacia cincinnata, Acacia crassicarpa, Acacia implexa, Acacia koa, and Acacia mangium grew significantly faster under the high fertility treatment. Three species, A. cincinnata, A. crassicarpa, and A. mangium, are recommended for planting on infertile acid soils. The volume of A. koa was increased ten-fold by the high fertility treatment. Additional study on koa's nutritional requirements is suggested in order to identify the nutrients contributing to this increased growth.     

Canopy tree development and undergrowth bamboo dynamics in old-growth Abies–Betula forests in southwestern China: a 12-year study

Interactions between forest canopy characteristics and plants in the forest understory are important determinants of forest community structure and dynamics. In the highlands of southwestern, China the dwarf bamboo Bashania fangiana Yi is an understory dominant beneath a mixed canopy of the evergreen Abies faxoniana (Rheder & Wilson) and the deciduous Betula utilis (D. Don). The goal of this study was to better understand the role of bamboo dominance, canopy characteristics, and periodic bamboo dieback on forest development. To achieve this goal, we measured tree seedling, tree saplings, and trees, forest canopy characteristics, and bamboo cover in permanent forest (n = 4) and gap plots (n = 31) in a mixed A. faxoniana and B. utilis forest in Sichuan, China. Dwarf bamboos died off in 1983 in the gap plots, and in three of the four forest plots. Forest development was assessed for the period 1984–1996. The seedling bank in forest and gap plots increased after bamboo die-off. A. faxoniana seedlings increased more than B. utilis in forest plots; the opposite pattern characterized gap plots. The proportion of seedlings on raised micro-sites on the forest floor also changed and new seedling were more abundant on the forest floor. By 1996, bamboo seedling cover and biomass had recovered to ca. 45% or their pre-flowering values. Rates of bamboo seedling recovery were faster beneath canopy gaps and deciduous trees than beneath forest or evergreen trees. Tree mortality exceeded recruitment in plots with dense bamboo; the opposite pattern was found in the plot with little bamboo. The mortality rate for B. utilis trees (2.4% year⁻¹) was higher than that for A. faxoniana (0.8% year⁻¹) and forests with dense bamboos became more open over the census period. Tree mortality was size-dependent and intermediate sized trees had the lowest rates of mortality. Stand basal area increased mainly due to greater basal area gain than loss for A. faxoniana. Interactions between tree species life history, canopy type, and bamboo life-cycles create heterogeneous conditions that influence tree and bamboo regeneration and contribute to the coexistence of A. faxoniana and B. utilis in old-growth forests in southwestern China.     

地形因子对黄甜竹引种栽培的影响

研究了不同坡位、不同海拔等地形因子对黄甜竹(Acidosasa edulis)引种栽培的影响。结果表明:1)坡位对黄甜竹的造林成活率、发笋数及平均胸径均有显著影响,造林第2年发笋数和竹高生长显著增加;2)生长在下坡位的黄甜竹,竹林平均胸径和平均高最高,而生长在中坡位和上坡位的竹林各项生长指标相对较低;3)坡位对黄甜竹生物量分布的影响较大,黄甜竹各构件生物量分配大小排序为秆 > 枝 > 叶;4)随着海拔高度的上升造林成活率、当年新发笋数、第2年新发笋数呈减小的趋势,平均胸径、平均竹高、单株生物量呈增加趋势。试验结果可为西南地区黄甜竹营林和推广提供理论参考。     

赤霉素浸种对白藤种子萌发特性的影响

白藤是中国热带、南亚热带森林中重要的伴生藤本和非木质森林资源。为探究白藤种子萌发的最佳处理,采用赤霉素（GA₃）浸种对白藤种子发芽特性进行研究。结果表明：发芽率以50 mg/L的GA₃溶液浸种处理最高（91.82%）,该处理能提高白藤种子发芽率;发芽势和发芽指数均以400 mg/L GA₃溶液浸种处理最高（83.18%,16.67）,20 mg/L GA₃溶液浸种处理最低（50.65%,11.50）。建议采用GA₃溶液浸种与催芽技术相结合,以提高白藤种子发芽率、发芽势和发芽指数。