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1.
Riassunto Viene proposta la scheda morfopalinologica diCalocedrus decurrens (Torr.) Florin come ulteriore contributo ad un più ampio studio sui pollini di Pinophyta ornamentali. Sono stati esaminati granuli freschi ed acetolizzati provenienti da tre stazioni e non sono state rilevate significative differenze morfometriche nei campioni di diversa provenienza.  相似文献   

2.
The present paper is the Supplement 2 to the Flora of Xizang, based upon a collection in 1980 by Mr. W. L. Chen et al. from Mêdog, the south-eastern part of Xizang. In the paper 11 new species are desribed and 10 new-record species are reported. All the type specimens are kept in the Herbarium of the Institure of Botany, Academia Sinica (PE).  相似文献   

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Riassunto La scheda morfopalinologica diSequoia sempervirens (Lamb.) Endl. continua lo studio sulle Pinohyta ornamentali più frequenti in Torino. È esaminato polline fresco ed acetolizzato proveniente da due stazioni e la provenienza non determina variazioni significative dei parametri morfometrici.
Summary The morphopalynological card ofSequoia sempervirens (Lamb.) Endl. is a new contribution to the comprehensive study on pollen of ornamental Pinophyta in Turin. Fresh and acetolysed grains from two stations are examined, and for all parameters no significative differences were observed in relation to the collection site.
Parole chiave: Sequoia sempervirens(Lamb.) Endl., Flora Palinologica Italina, Sezione Aeropalinologica.  相似文献   

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《生物多样性》2021,29(4):559
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Río Tinto (Huelva, Spain) is located in one of the most important mining regions in the world. Its soils are characterized by their extreme acidity and elevated concentrations of heavy metals. Due to these characteristics, the Tinto ecosystem is considered unique and an ideal location to study biological adaptations to this type of habitat. Plant species that present these adaptations might be useful to mining and other metal pollution restoration programs. This study reports the results for the screening of Ca, Mg, Na, Mn, Fe, Ni, Cu, Zn, As, and Pb in aerial tissues of 97 plant species from the Tinto basin flora. In addition, plant–soil relationships were analyzed using the biological absorption coefficient (BAC) to detect the main plant adaptations in the Tinto flora. The species selected are representative of the biomass of the main dominant edaphophile and climatophile vegetation communities of the three river sections, forest, and subseral stages. Plant and soil elemental analyses were performed using inductively coupled plasma–mass spectrometry technique (ICP-MS). The results indicate that in general, Tinto flora shows a pattern of accumulation of the analyzed elements in aerial tissues which agrees with the nutritional requirements of vascular plants (macronutrients > micronutrients > indifferent or toxic elements). Among macronutrients, Ca seems to be an essential element in this habitat. This element accumulates in the aerial plant tissues. Basically, the Río Tinto flora is made of Fe, Cu, Zn, Ni, As, and Pb excluders, although some analyzed species of Erica, Quercus, Lavandula, Cistus, Genista, and Cytisus genera can be considered Mn accumulators. The results of this study make up a body of fundamental knowledge of the strategies used by plants to thrive in habitats with high concentrations of toxic heavy metals. This information is vital when it comes to planning a restoration program. Plants must be selected and used according to the requirements, always respecting the characteristics of the territory and facilitating the development of suitable vegetation.  相似文献   

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Ohne Zusammenfassung  相似文献   

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China, under highly varied ecological conditions resulted from wide latitudinal and altitudinal ranges and from the adequate precipitation, has developed a very rich flora of great diversity. As far as flowering plants are concerned, there are 2980 genera, 214 of which, belonging to 64 families, are endemic. Among these endemic genera, there are 9 genera of taxads and conifers, 19 genera of monocots and others of dicots. Of the approximately 129 herbaceous endemic genera in the Chinese flora as a whole, about 22 (17%) are annual and 107 (83%) are biennial or perennial. In the present paper the ecological distribution, the nature of endemic genera and the centers of endemism are discussed. 1. Three types of endemic genera are distinguished, neoendemics, palaeoendemics and active epibiotics, The endemic genera in the flora of China are, for the most part, considered to be very old ones, and most of them are of temperate nature. 2. the degree of endemism in our 22 floristic regions is shown in Figure 1. The areas richest in endemic genera in the Chinese flora as a whole are the 13, 16 and 17 regions. The poorest are the 2, 4, 9 and 10 regions, and no one in the 1 and 3 regions These results on floristic richness are of general applicability. As shown in table 1, the difference in the degree of endemism among the seven Chinese floristic subkingdoms are most pronounced. 101 endemic genera are known to occur in one subkingdom, 72 to occur in two subkingdoms, and 3 to occur in four subkingdoms, only one genus widely distributed in five subkingdoms. However, there is no genus occurring in seven subkingdoms. The difference in the degree of endemism in each subkingdom reveals that the distribution of endemic genera is not well-distributed in the Chinese flora as a whole. Analysis of the vertical distribution of the 200 endemic genera of the Chinese flora bears out that there is no evident increase in endemism as a whole with altitude. 3. Three centers of endemism are found (Fig. 2). These are as follows: a). Eastern Sichuan-western Hubei center. b). Southeastern Yunnan-western Guangxi center. c). Western Sichuan-northwestern Yunnan center. The degree of endemism andcharacters of endemic genera in each center are discussed.  相似文献   

9.
《化石》2018,(4)
正如前所述,正是随同"贝格尔号"巡洋舰环球考察其间目击到的一些事实,尤其是加拉帕戈斯群岛上的鸟类及其他生物显示出来的性状差异,使达尔文"深受感动"。达尔文当时就思索:"显然可知,只有依据一种推测,就是物种在逐渐地发生变异,才可以去解释这一事实以及其他很多事实。""可是,同样也显明可知,不论是周围环境的作用,或者是生物的意志(特别是就植物而言),都不能够解释各类生物极其良好地适  相似文献   

10.
Riassunto Nell'ambito del progetto «Flora Palinologica Italiana» e proseguendo lo studio delle Corylaceae, è qui presentata la scheda diCarpinus betulus L., con alcune osservazioni sul numero/posizione delle aperture e sulle principali differenze tra polline «fresco» e polline acetolizzato.
Summary According to the program «Palynological Italian Flora», and continuing the study of the Italian Corylaceae, the palynological card ofCarpinus betulus L. is shown. The study is carried out on pollen coming from three different localities and regards both «fresh» and acetolyzed pollen. For each sample, measurements are carried out on 30 «fresh» pollen grains in glicerol jelly and on 30 acetolyzed pollen grains in water/glicerol 1/1; general observations regard 500 «fresh» and 500 acetolyzed pollen grain/sample. Some morphological observations on the aperture number/position and differencies between «fresh» and acetolized pollen are pointed out.
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(S)-(?)-Vertinolide 1 was synthesized via the tetronic acid derivative 6 from (S)-(?)-tetrahydro-2-methyl-5-oxo-2-furancarboxylic acid 3. (±)-Vertinolide was also synthesized from (±)-3.  相似文献   

13.
A list of 244 bryophytes (67 hepatics and 177 mosses) from Sierra de Peña Sagra (Cantabria) is given; Ctenidium molluscum var. sylvaticum is new record from the Iberian Peninsula and 27 taxa are new records for this province. We remark the presence of Cephaloziella hampeana, Lejeunea lamacerina, Kurzia pauciflora, Sphagnum brevifolium, S. girgensohnii, Hypnum hamulosum, Orthotrichum consimile, Ulota bruchii, Mnium lycopodioides, Plagiomnium medium subsp. medium, Grimmia anomala and Tortella densa.  相似文献   

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A list including 114 selected subspecies names from the bookSchübler andMartens, Flora von Würtemberg, 1834 is given. Twenty of them are very important for the present taxonomic classification.  相似文献   

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The bryophyte flora and vegetation have been studied in aquatic and wet environments of Valencia County (eastern Spain). A catalogue of 74 taxa is given, 3 species are new for eastern Spain and 6 for provinces of Valencia County (Valencia = 4, Castellón = 2). Aquatic communities have been studied according to the Braun-Blanquet (1952) method. Nine associations belonging to the classes Adiantetea, Montio-Cardaminetea and Platyhypnidio-Fontinalietea have been recognized. One association has been described as new, Fontinaletum hypnoidis ass. nova, which always grows submerged in calcareous, unpolluted and flowing water. Ecological and syntaxonomical data on problematical communities in the Mediterranean region (EucladioAdiantetum, Eucladietum and Eucladio-Didymodonetum) are given, as well as information on the dynamics of the communities.  相似文献   

19.
根据当年亲身经历及考察日记,真实记录了我国科考队动物组于1958年第1次攀登并考察珠穆朗玛峰情况,介绍了所发现的我国鸟类和哺乳动物新纪录和新亚种,以及首次证实并确认的卡玛河谷等地在世界动物地理区划上的具体区界。  相似文献   

20.
根据当年亲身经历及考察日记,真实记录了我国科考队动物组于1958年第1次攀登并考察珠穆朗玛峰情况,介绍了所发现的我国鸟类和哺乳动物新纪录和新亚种,以及首次证实并确认的卡玛河谷等地在世界动物地理区划上的具体区界。  相似文献   

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