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贵州野生钩藤生长环境调查研究 总被引:3,自引:0,他引:3
对贵州野生钩藤生长环境、气候状况、土壤理化特性及蕴藏量进行调查研究,结果表明:贵州野生钩藤资源分布在海拔450 ~1 250 m范围内,喜温暖、湿润的环境,大部分分布在阴坡,主要生长在林下的坡地,坡度从30~70度不等,多有岩石;伴生植物主要是高大乔木,其次是灌木,还有带刺的蔷薇科藤本植物及喜阴的草本植物;钩藤生长地土壤类型属于壤土,土壤含水量高,有机质含量较低,土壤pH属于酸性范围,碱解氮在缺乏范围,土壤有效磷比较低,土壤速效钾属于丰富水平.野生钩藤资源蕴藏量很少. 相似文献
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幼苗是植被恢复演替的基础, 在生态系统中具有非常重要的作用。为了探索黄土丘陵沟壑区坡沟立地环境下幼苗的存活特征, 在陕西省安塞县宋家沟和纸坊沟流域设置15个固定样地进行定点动态监测, 运用单因素方差分析法和系统聚类分析法对不同立地环境下的幼苗密度和幼苗存活率进行了分析。结果表明: 1)不同坡沟立地环境下, 幼苗存活特征差异明显, 整体表现为阳坡幼苗密度较小而存活率较高, 阴坡幼苗密度较大但存活率较低。2)细裂叶莲蒿(Artemisia gmelinii)、菊叶委陵菜(Potentilla tanacetifolia)、阿尔泰狗娃花(Heteropappus altaicus)等物种具有较高的幼苗存活率, 在生存竞争中幼苗是以“质”取胜; 而猪毛蒿(Artemisia scoparia)、中华苦荬菜(Ixeris chinensis)、阴行草(Siphonostegia chinensis)等物种具有较高的幼苗密度, 在生存竞争中是以“量”取胜。3)同一物种在坡沟立地环境下表现出不同的存活曲线, 不同物种在不同立地环境下也可呈现同一存活曲线; 细裂叶莲蒿、菊叶委陵菜、长芒草(Stipa bungeana)、阿尔泰狗娃花、兴安胡枝子(Lespedeza davurica)等物种, 幼苗不仅在雨季存活能力强且具有较强的越冬能力; 猪毛蒿、香青兰(Dracocephalum moldavica)、臭蒿(Artemisia hedinii)等物种在雨季前幼苗存活能力较强, 但冬季存活能力弱。4)坡面不同微环境下幼苗存活特征也存在差异, 即微环境的改变在一定程度上影响着幼苗的生长、存活和越冬。因此, 在黄土丘陵沟壑区应根据物种幼苗存活特性对幼苗进行适当的抚育管理, 这将有利于幼苗的建植和植被更新。 相似文献
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贵州苗药黑骨藤化学成分的研究 总被引:4,自引:0,他引:4
利用色谱技术从黑骨藤(Periploca forrestii Schltr)中分离得到9个化合物,通过理化性质和光谱分析,分别鉴定为:α-香树脂醇(I),α-香树脂醇乙酸酯(Ⅱ),27-羟基-α-香树脂醇(Ⅲ),β-香树脂醇(IV),β-香树脂醇乙酸酯(V),熊果酸(Ⅵ),β-谷甾醇(Ⅷ),β-胡萝卜甙(Ⅷ),大黄素(Ⅸ).化合物Ⅰ,Ⅲ,Ⅳ,Ⅴ为首次从该植物中分离得到. 相似文献
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五龙参(Panax quinquefolius Linn),也称花旗参、西洋参,是国际极其珍贵的药用植物之一,本文系统的研究了林下地形环境因子对五龙参栽培的影响,通过定位定量的不同观测点的试验数据,得出四种地形和低山丘陵北坡或东北坡的中上坡位,海拔高度330-450m的高地环境,栽培五龙参有利于获得高产。 相似文献
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福建“柘荣太子参”栽培环境的道地性研究 总被引:2,自引:0,他引:2
特定的生态环境是道地药材的天然孕床。通过对柘荣县的地理、气候、地貌、土壤等自然条件分析,表明了"柘荣太子参"生长与其它太子参主产区相同的亚热带季风气候下,其产地的高海拔昼夜温差大,促进了其太子参块根光合物质的积累;温凉的夏季延长了其生长期;充足的雨量满足了其自然生长的需求;红土为主的栽培土壤保证了其微量元素丰富和外观色泽晶黄,形成其道地性特征。 相似文献
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通过对贵州省施秉县白云岩喀斯特地区大塘下洞和岩孔洞的深入调查,共采集洞穴动物标本1541号,隶属于32科61种.其中岩孔洞共采集洞穴动物标本668号,隶属于17科30种,大塘下洞共采集洞穴动物标本873号,隶属于24科37种.经数理统计分析,在2个洞穴弱光带中,除物种优势度外,群落多样性均最大.在所有群落中,多样性最高的是群落E,优势度指数最高的是群落C.用Pearson相关系数进行环境因子、物种或群落多样性的相关性分析,结果显示群落多样性各指数之间相关性较显著,温度和群落多样性之间也存在显著相关关系,土壤中砷对物种或群落多样性也有影响.从研究的环境因子与物种或群落多样性的欧氏距离分析来看,除湿度与其他系数的欧氏距离较大外,其余系数间欧氏距离均较小,最小欧氏距离为0.22.表明洞穴动物群落与环境因子之间相关性较显著.经土壤污染评价,岩孔洞严重受到重金属汞和砷的污染,对洞穴动物群落结构产生严重影响. 相似文献
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环境解说是自然保护地实现自然保护与环境教育目标的重要手段。目前我国自然保护地对解说资源的时空分布研究不足, 且缺乏相应的实地调查方法, 限制了解说系统的发展, 难以满足公众对自然认知的需要, 达不到环境教育的目的。开展解说资源的调查与研究, 有助于更好地展示保护地的资源独特性和重要性。本文以九寨沟国家级自然保护区芦苇海解说步道为例, 总结了解说资源的6个选择标准, 并对区域的解说资源进行调查和监测, 以期为我国自然保护地体系的环境解说资源调查和解说系统构建提供方法借鉴。芦苇海解说步道共筛选得到195种解说资源, 包括植物与菌类100种、动物62种、生态系统类型5种、地质与水文7种、天象与气候2种、文化资源19种。空间上, 植物与菌类、动物和生态系统类解说资源主要分布于内侧步道, 而文化类解说资源在外侧栈道分布更多; 时间上, 夏秋季解说资源数量最多, 冬春季较少, 且动植物与菌类解说资源的数量具有明显的季节性。基于解说资源的属性、意义和分布特点, 采用主旨式解说(thematic interpretation)方法设计了8条解说主旨, 为解说内容的组织提供参考。 相似文献
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半枝莲中印黄芩甙的R-HPLC分析代雪平魏波(河南省药检所,郑州450003)(河南省人民医院药剂科,郑州450003)R┐HPLCanalysisofscutelarinfromScutelariabarbataD.DonDaiXue-Ping(H... 相似文献
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半枝莲中二萜内酯和黄酮化合物的分离和鉴定 总被引:1,自引:0,他引:1
半枝莲(Scutellaria barbata D.Don)为唇形科黄芩属植物,全草入药,具有清热解毒,化瘀利尿,消肿止痛和抗癌等功效。国内学者报道从全草中分得红花素(carthamidin)、异红花素(isocarthamidin)、印黄芩甙(scutellarein)、β-谷甾醇(β-sitosterol)、硬脂酸(stearic acid)和生物碱。台湾学者从中分离得汉黄芩素(wogonin)、5-羟基-7,8-二甲氧基黄酮(5-hydroxy-7,8-dimethoxyflavone)、半枝莲素(Rivularin)。我们从全草的乙醇提取液中分得两个化合物,经鉴定为汉黄芩素、新穿心莲内酯,该内酯在本植物中属首次发现。 相似文献
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Abstract. Experiments were carried out on Pinus radiata (D. Don) trees grown as cuttings from clonal parent stock. Some of these trees were about 0.4 m high while others were about 5 m high; all were grown in containers. The stem diameters at the tops and at the bottoms of the large trees, rates of photosynthesis, and needle water potentials were measured both when the trees were well watered and as they dehydrated after water was withheld. The water potentials of well-watered plants was highest in the small trees and lowest at the top of the large trees. When water was withheld, photosynthesis was in most cases unaffected by a small reduction in water potential, but the rate of photosynthesis fell as water potentials declined further. The stems of the large trees expanded at a constant rate when the trees were well watered and for part of the dehydration period, while subsequent stem shrinkage and the fall in photosynthesis both occurred at approximately the same time.
Water potentials increased little in the 24 h after rewatering, and significant rates of photosynthesis were not measured until 2 or 3 d later while renewed stem expansion was not measured until 2 d after rewatering.
Water deficits reduced the lumen diameter of newly matured stem tracheids, but increased the thickness of their walls. After 1 month of water potentials of about −2.4 MPa, tracheid lumen diameter and wall thickness were both much reduced, and this reduction continued in tracheids maturing shortly after rewatering. 相似文献
Water potentials increased little in the 24 h after rewatering, and significant rates of photosynthesis were not measured until 2 or 3 d later while renewed stem expansion was not measured until 2 d after rewatering.
Water deficits reduced the lumen diameter of newly matured stem tracheids, but increased the thickness of their walls. After 1 month of water potentials of about −2.4 MPa, tracheid lumen diameter and wall thickness were both much reduced, and this reduction continued in tracheids maturing shortly after rewatering. 相似文献
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Summary YoungPinus radiata D. Don were fertilized with copper oxychloride and copper sulfate on a random block basis with four replicates. Roots, needles,
stems and shoot apices were analyzed separately for Cu, Fe, Mn and Zn contents at different times from fertilization.
The results showed a rapid plant copper absorption, no effects being found on the Fe, Mn and Zn content.
The dynamic internal distribution of copper among different plant parts is shown.
The treatments applied did not cause any phenotypical alteration nor phytotoxicity in the plants, and no significant effect
of the fertilizer chemicals on each other. 相似文献
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Nitrogen allocation and carbon isotope fractionation in relation to intercepted radiation and position in a young Pinus radiata D. Don tree 总被引:1,自引:2,他引:1
N. J. Livingston D. Whitehead F. M. Kelliher Y.-P. Wang J. C. Grace A. S. Walcroft J. N. Byers T. M. Mcseveny & P. Millard 《Plant, cell & environment》1998,21(8):795-803
The three dimensional distribution of intercepted radiation, intercellular CO2 concentration (Ci) and late summer needle nitrogen (N) concentration were determined at the tips of all 54 branches in a 6·2-m-tall Pinus radiata D. Don tree growing in a New Zealand plantation. Measurements included above- and below-canopy irradiance, leaf stable carbon isotopic composition (δ13C) and tree canopy architecture. The radiation absorption component of the model, MAESTRO, was tested on site and then used to determine the branch tip distribution of intercepted radiation. We hypothesized that in branch tip needles: (i) the allocation of nitrogen and other nutrients would be closely associated with the distribution of intercepted radiation, reflecting carbon gain optimization theory, and (ii) Ci would predominantly reflect changes in photosynthetic rate (A) rather than stomatal conductance (gs), indicating that the increase in A for a given increase in N concentration was larger than the corresponding increase in gs. Needle nitrogen concentration was poorly related to intercepted radiation, regardless of the period over which the latter was calculated. At a given height, there was a large azimuthal variation in intercepted radiation but N concentration was remarkably uniform around the tree canopy. There was, however, a linear and positive correspondence between N concentration and δ13C and needle height above ground (r2 = 0·73 and 0·68, respectively). The very strong linear correspondence between N concentration and Ci (r2 = 0·71) was interpreted, using gas exchange measurements, as supporting our second hypothesis. Recognizing the strong apical control in P. radiata and possible effects of leaf nitrogen storage in an evergreen species, we propose that the tree leader must have constituted a very strong carbon sink throughout the growing season, and that the proximity of branch tip needles to the leader affected their photosynthetic capacity and nutrient concentration, independent of intercepted radiation. This implies an integrated internal determination of resource allocation within the tree and challenges the current convention that resources are optimally distributed according to the profile of intercepted radiation. 相似文献
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D. WHITEHEAD N. J. LIVINGSTON P.M. KELLIHER K. P. HOGAN S. PEPIN T.M. MCSEVENY J.N. BYERS 《Plant, cell & environment》1996,19(8):949-957
Sudden but transient changes in the fraction or illuminated foliage area in a well-watered 7-year-old Pinus radiata D. Don tree were imposed by completely covering either the upper 22% or the lower 78% of the foliage for periods of up to 36 h. Measurements of transpiration flux density (E), tree conductance (gt), stomatal conductance (gs) and net photosynthesis (A) were made to test the hypothesis that compensatory responses would occur in the remaining illuminated foliage when the cover was installed. When the lower foliage was covered there was an immediate decrease in gt. However, when tree conductance was normalized with respect to the illuminated leaf area (gt'), it increased between 50 and 75%, depending on the value of air saturation deficit (D). The effect was also apparent from concurrent measurements of increases in gs and A up to 59 and 24%, respectively, for needles in the top third of (he crown. When the cover was removed these effects were reversed. The changes in the lower foliage when the upper foliage was covered were much smaller. Changes in bulk needle water potential were small. It is suggested that the observed responses occurred because of a perturbation to the hydraulic pathway in the xylem that could have triggered the action of a chemical signal to regulate stomatal conductance and photosynthesis. 相似文献
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Fritillaria cirrhosa D. Don is a renowned traditional Chinese medicine plant that is mainly distributed in the southeastern margin of the Qinghai–Tibet Plateau. The overexploitation in the recent years has led to a sharp decline of this undomesticated resource. Analyzing the impact of climate change on the geographic distribution of F. cirrhosa is meaningful for its conservation and domestication. In this study, the maximum entropy model (Maxent) was used to simulate the distribution of F. cirrhosa in relation to the current and future climatic conditions. The maximum temperature of the warmest month (Bio 5) and the precipitation of the warmest quarter (Bio 18) were the two most important bioclimatic variables determining the distribution of F. cirrhosa. Based on the predicted level of climatic warming, a further reduction of the geographic distribution of F. cirrhosa is to be expected. This study demonstrated the necessity and urgency of establishing more effective ways to protect the natural F. cirrhosa resources and developing artificial cultivation methodology. 相似文献
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D. C. MORGAN D. A. ROOK† I. J. WARRINGTON H. L. TURNBULL 《Plant, cell & environment》1983,6(9):691-701
Abstract. Plants of Pinus radiata of two physiological ages, juvenile (seedlings and micropropagated plantlets) and adult (rooted cuttings from mature trees), were grown under lighting fromthree combinations of metal halide (MH) and tungsten halogen (TH) lamps for up to 10 months in controlled environment rooms. The three lamp combinations, MH alone, 50: 50 MH: TH and 25:75 MH: TH by wattage, produced red: farred ratios of 4.59, 1.51, and 1.15, respectively. Photosynthetic photon flux density was 700 μmol m−2 s−1 . An increase in proportion of TH lamps markedly increased shoot elongation and internode length, decreased numbers of fascicles per unit stem length and increased the proportion of stem weight in both juvenile and adult material. In addition, in adult material, it increased the number of fascicle initials and expanded fascicles per growth flush, reduced the duration of the 'rest' phase between growth flushes, accelerated the rate of elongation growth during each flush, and increased apical dominance. Tracheid length, but not diameter or wall thickness, was significantly affected by light quality and found to be associated with longer internodes. Any treatment effects on needle weight or length, stem diameter or root weight were non-significant or very small. Different clones from either the juvenile micro-propagated material or the mature rooted cuttings each showed similar patterns of response, although they often differed in the degree of response to light quality. The main response could be related solely to the red: far-red ratio and the calculated phytochrome photoequilibrium. This is the first report of phytochrome-controlled photomorphogenesis in older specimens of a woody perennial. Recommendations for artificial light sources for growing P. radiata and some ecological implications of the results are presented. 相似文献