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高海拔地区不同海拔对菊花植株生长与品质的影响   总被引:1,自引:0,他引:1  
通过田间测定引种栽培于四川省宝兴县不同海拔高度菊花植株的株高、地径、分枝数等营养生长指标及花数量、花重量、花直径、花厚度等生殖生长指标,采用高效液相色谱法测定菊花样品的绿原酸含量、木犀草苷含量、异绿原酸A含量等主要品质指标,并对测得数据进行方差分析和相关性分析,研究比较了高海拔地区不同海拔高度对菊花植株生长与品质的影响。结果表明:海拔梯度对菊花株高、花数、花重量、花直径、花厚度、木犀草苷含量和异绿原酸A含量均有显著影响(P0.05),对地径、分枝数和绿原酸含量无显著影响(P0.05),其中株高、花数和花直径与海拔梯度相关性显著(P0.05)。除分枝数和地径外,高海拔地区不同海拔高度对菊花植株的生长影响较大,在一定海拔范围内(2051~2 405m),海拔高度对菊花品质形成的影响较小,据2010版《药典净对菊花有效成分最低限量标准,海拔2051~2598 m所产的菊花均符合药用条件,以海拔2 329 m左右所产的菊花品质较佳。研究结果可为高海拔地区引种栽培菊花提供理论依据。  相似文献   

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The nutritional status of plants from high altitudes   总被引:28,自引:0,他引:28  
Ch. Körner 《Oecologia》1989,81(3):379-391
Summary Are plants at high altitudes short in nutrients? In order to answer this question the mineral nutrient content of leaves from over 150 plant species from 9 different mountain areas of all major climatic zones were analyzed (Kjeldahl nitrogen in all, phosphate in half of the samples, K, Mg, Mn, Ca in the Alps only). The majority of data are from herbaceous perennials, but shrubs and trees were studied as well. N-partitioning was studied in 45 herbaceous species from contrasting altitudes in the Alps. The survey falls into three categories: (1) comparisons of whole communities of species from contrasting altitudes, (2) analysis of altitudinal gradients, and (3) additional collections from high altitude sites alone. Unlike the other mineral nutrients, nitrogen content follows consistent altitudinal and latitudinal trends. The higher altitude sample always had higher N content per unit leaf area, irrespective of life form, wherever comparable plants (the same or related species) were investigated at contrasting altitudes. N content per unit dry weight (%) increased with altitude in herbaceous plants (in some species >4%), but was remarkably stable in evergreen woody plants (around 1%). The mean fraction of total plant N allocated to leaves of herbaceous plants in the Alps was the same at low and high altitude (1/3 of total). Leaf N (%) from the regional upper limits of higher plant life reveals a latitudinal decrease from subarctic to equatorial mountains, which may be related to the duration of annual leaf activity. Since mean N content per leaf area hardly differs between the uppermost sites, life span expectation (sink-duration) seems to control carbon investments rather than N input per leaf area. The growth of leaves at high altitude seems to be controlled in a way that leads to comparatively high nutrient contents, which in turn support high metabolic activity. Inherent developmental growth constraints inhibit nutrient dilution in the plant body and thus defy the application of classical concepts of plant-nutrient versus soil-nutrient relations developed for lowlands and in particular for cultivated plants. The results re-emphasize the global significance of links between nitrogen content, leaf sclerophylly, leaf longevity and photosynthetic capacity.Dedicated to Prof. Walter Larcher on the occasion of his 60th birthday, with thanks for leading me to comparative plant ecology  相似文献   

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Observations (mid-July) were made, at high altitudes (3,080 m to 4,267 m, White Mountains, California), of the radiative physical and physiological parameters of importance to man. The data was used to show how man was actually coupled to the climatological events and processes going on at the physical-horizontal interface. Such observations were then used to test theoreticalempirical models predicting such interactions between man and the environment. High correlations were found between hypothesis and observations during the investigational period. Subsequently, an all-year simulation was conducted which attempted to predict the annual march of net radiation on the human and its causal components for high elevations in arid regions.
Zusammenfassung In der Höhe von 3.080 bis 4.267 m (White Mountain, California) wurden Mitte Juli Strahlungsmessungen vorgenommen. Die Messungen sollten die enge Kopplung der menschlichen Funktionen mit den klimatischen Bedingungen aufzeigen. Die Beobachtungen wurden weiter zur Prüfung theoretischempirischer Modelle zur Voraussage von Mensch-Umwelt Beziehungen verwendet. Während der Untersuchungsperiode wurden signifikante Korrelationen zwischen Hypothese und Beobachtung gefunden. Deshalb wurde die Beziehung simuliert für alle Monate berechnet, um den Jahresgang der Strahlungsbilanz auf den Menschen und ihre Komponenten für grosse Erhöhungen in ariden Gebieten vorauszusagen.

Resume A la mi-juillet, on a effectuê des mesures du rayonnement entre 3.080 et 4.267 m d'altitude dans les White Montain de Californie. Ces mesures avaient pour but d'établir une relation étroite entre les fonctions humaines et les conditions climatiques ambiantes. Ces observations ont en outre été utilisées pour vérifier des modèles théoriques et empiriques, modèles permettant un pronostic des réactions de l'homme selon le milieu. On a obtenu de hautes corrélations entres les hypothèses émises et les observations faites durant la période d'investigations. Par conséquent, on a calculé pour chaque mois la relation trouvée afin de prévoir les réactions humaines à haute altitude et en climat aride sur la base de l'évolution annuelle de la radiation nette.
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高寒生态系统微生物群落研究进展   总被引:4,自引:1,他引:4  
高寒生态系统分布在高纬度或高海拔、气候寒冷的地区,包括北极苔原、高山苔原、青藏高原等.高寒生态系统对气候变化非常敏感,其土壤中储存大量的有机碳,对全球的碳平衡起关键作用.微生物是生物地球化学循环的主要驱动者,微生物群落对气候变化的响应和反馈影响生态系统的功能与稳定性.本文回顾了高寒生态系统微生物群落组成、多样性与空间分布,以及微生物群落对气候变化(增温、氮沉降、火干扰)的响应,为拓展我国高寒生态系统微生物研究提供基础.  相似文献   

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The effects of light on the growth and development of giant kelp   总被引:1,自引:1,他引:0  
Xiugeng  Fei  Neushul  M. 《Hydrobiologia》1984,116(1):456-462
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发育时期对紫茎泽兰化感作用的影响   总被引:23,自引:0,他引:23  
韩利红  冯玉龙 《生态学报》2007,27(3):1185-1191
为探讨紫茎泽兰化感作用与其入侵性的关系,利用生物检测法研究了不同发育时期紫茎泽兰叶片水提液对4种本地草本植物种子萌发和幼苗生长的影响。结果表明,高浓度时紫茎泽兰叶片水提液能显著抑制4种本地植物种子发芽率、发芽速度,但低浓度时有时抑制作用不显著,甚至有促进作用;除狗肝菜胚轴生长外,不同浓度下紫茎泽兰叶水提液均能抑制4种本地植物胚轴和胚根生长,但有时对胚轴生长的抑制作用不显著,甚至有促进作用。不同植物和同种植物的不同参数对紫茎泽兰化感作用的敏感程度不同,拔毒散和狗肝菜的种子萌发参数较敏感,莎草砖子苗的生长参数较敏感,种子发芽速度和胚根生长较敏感。总的看,随发育时间的增加,紫茎泽兰抑制本地植物种子萌发和幼苗生长的最低叶片提取液浓度减小,相同浓度下叶片水提液对本地植物的抑制作用增强,表明紫茎泽兰化感作用增强。化感作用在紫茎泽兰入侵的不同阶段所起的作用可能不同。  相似文献   

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The lowered partial pressure of oxygen at high altitude is one of the severest and most pervasive environmental stresses affecting human populations. Virtually all organ systems and physiological functions are affected by hypoxia, and only elaborate modern technology can temporarily ameliorate the hypoxic stress of altitude exposure. The biological and behavioral responses of newcomers, sojourners, and native residents at higher elevations could provide a paradigm of the study of man's adaptation to the physical environment. Cardiorespiratory characteristics are closely related to altitude exposure, and certain alterations in these characteristics constitute the principal adaptive responses of the organism to hypoxia. However, not all altitude-related characteristics are beneficial to the organism; some peculiar characteristics occurring at high altitude may be without benefits, or may even be pathological and maladaptive. The roles of age, sex, race, physical condition, nutrition, and intensity and frequency of exposure during growth and development of altitude-related characteristics are not entirely understood. Moreover the influence of even large circulatory and respiratory alterations, on tissue oxygen tension may be small, and their adaptive significance difficult to evaluate. An equivalent level of functional adaptation might be achieved through differing combinations of structural, functional, and behavioral characteristics. It is concluded that more rigorous evaluations of adaptation to the environment are needed.  相似文献   

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水分胁迫效应对冬小麦生长发育影响的试验研究   总被引:17,自引:0,他引:17  
利用大型水分试验场遮雨棚遮档自然降水,采用人工定量补水进水进行冬小麦土壤占田间持量40%-50%、45%-50%、50%-55%、50%-60%、55%-60%、60%-70%持续时间分别为5、10、15d水分胁迫处理的控制试验。试验结果表明:控制结束复水后,50%-60%、55%-70%水分胁迫处理诱发冬小麦根、茎、叶、总生物量显著增长或明显减缓其衰老速率。土壤含水量占田间持水量50%-60%处理,具有明显的增产、节水效率,确定土壤含水量占田间持水量55%为冬小麦拔期水分胁迫应增产节水的水分临界指标。  相似文献   

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Human nutrition in cold and high terrestrial altitudes   总被引:1,自引:0,他引:1  
The calorie and nutritional requirements for a man working in an alien hostile environment of cold regions and high altitude are described and compared to those of normal requirements. Carbohydrates, fats and vitamins fulfilling the caloric and nutritional requirements are generally available in adequate amounts except under conditions of appetite loss. However, the proteins and amino acids should be provided in such a way as to meet the altered behavioral and metabolic requirements. Work in extreme cold requires fulfilling enhanced calorie needs. In high mountainous regions, cold combined with hypoxia produced loss of appetite and necessitated designing of special foods.  相似文献   

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为进一步探讨自然环境因素对生长发育的影响,本文收集了14个省会城市1996年以来7-18岁107986(男56300,女51686)儿童青少年的身高、体重、胸围资料及体质测量当年的海拔、年降水量、年均气温和年日照时数资料,做海拔等自然环境因素与发育指标的Z-分数和发育分相关与回归分析。结果表明,从低海拔组到中海拔组、高海拔组,儿童青少年的生长发育指标逐步下降,其中体重与BMI有统计学意义(P0.05),低海拔组发育指标明显好于高海拔组;生长发育水平与海拔的相关系数大于年均气温和日照时数,与年降水量不相关;回归分析表明海拔每增加1000m,身高、体重、胸围和BMI分别减少0.112,0.101,0.043和0.118个Z-分数。在四项自然环境因素中,海拔对生长发育的影响最大,对身高、体重、胸围和BMI的贡献率分别是28.0%,26.8%,12.0%,16.8%。  相似文献   

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