scholarly journals Wissenschaftliche Ergebnisse der BRYOTROP-Expedition nach Zaire und Rwanda 6. Lebensformen und Adaptionen zur Wasserleitung und Wasserspeicherung in epiphytischen Moosgesellschaften im östlichen Kongobecken und den angrenzenden Gebirgsstöcken (Parc National de Kahuzi-Biega/Zaire, Forêt de Nyungwe/ Rwanda)

1995 ◽  
Vol 11 (1) ◽  
pp. 87-117 ◽  
Author(s):  
Harald Kürschner ◽  
Ulrike H. Seifert

Life forms, water conducting and water storing structures of epiphytic bryophytes are studied along an altitudinal gradient from the eastern Congo basin (tropical lowand zone) to the mountains of the East-African graben (tropical subalpine/alpine zone; BRYOTROP III-transect). Based on a phytosociological analysis, these adaptations were put in relation to the distribution pattern of the bryophyte communities, as well as to the ecological gradient. The interpretation is based on the mean percent cover of each group. The tropical lowland zone is dominated by the life form mat, which is distinctly correlated with watersacs and taxa of the Jubulaceae, Lejeuneaceae and Radulaceae. In the following perhumid montane zone a clear alteration concerning the life form and the adaptations can be observed. The physiognomy of the primary rain-forests now is dominated by fan-forming Plagiochila species which are standing off the phorophyte by its flattened shoots. They are able to condensate water vapour from the fogs as well as using the low light intensities. Within the epiphytes of the bamboo zone of the upper montane zone, similar adaptation strategies to those of the lowland zone can be observed. The communities of the anthropogeneous montane woodlands of this zone, which are rich in mosses, show an ecomorphological wide spectrum [weft and tall-turfs correlated with a central strand (hadrome), hyalocysts and rhizoids]. Within the tropical subalpine/alpine zone exposed to great diurnal variations of climate, mat, weft and cushion-forming tall-turfs dominate, indicating the more xeric conditions (drought stress) by 88 water storing structures (alar cells, central strand, hyalocysts, rhizoids). In this zone, also structures reach a high mean percent cover, which enables the condensation of water vapour from the fog and mist rising from the upper montane zone or which show a groove-like arrangement of the leaflets. This may be recognized as a mechanism enabling a permanent water supply as well as a drain off of surplus water.

1995 ◽  
Vol 11 (1) ◽  
pp. 129-149
Author(s):  
Wolfgang Frey ◽  
Harald Kürschner ◽  
Ulrike H. Seifert

Life strategies of epiphytic bryophytes are studied along an altitudinal gradient from the eastern Congo basin (tropical lowland zone) to the mountains of the East-African graben (tropical subalpine/alpine Zone; BRYOTROP III-transect). Three strategies, Colonists, Perennial shuttle species and Perennial stayers can be observed, which are further subdivided according to their reproduction tactic (high sexual reproductive effort, high asexual reproductive effort, moderately or low sexual and asexual reproductive effort). Of these, only taxa with a long life span (perennials) are of importance, indicating the unchanging and constant ecological conditions and long-lasting microsites, provided by the epiphytic habitats. The basis for the life strategy pattern analysis along the altitudinal gradient were plant sociological investigations and the determination of the mean percentage cover values for the different life strategy categories. By this, the distribution and occurrence of the different strategies within the communities and the altitudinal zones can be shown.  Typical for the epiphytes of the primary rain-forests of the tropical lowland and lower montane zone are Perennial shuttle species and Perennial stayers with moderately or low sexual and asexual reproductive effort. This strategy obviously is favoured by the well balanced, high temperature and humidity regime of these zones and typical of most of the liverworts, dominating the epiphytic communities. They are replaced in the montane rain-forests and cloudy moss forests of the upper tropical montane zone by Perennial shuttle species with high asexual reproductive effort, regenerating mainly by propagules and clonal growth. Within the secondary woodlands of this zone and the unique ericaceous woodlands and subpáramo of the African volcanos, Perennial shuttle species and Perennial stayers with high sexual reproductive effort reach a maximum, building regularly sporophytes under the already xeric and strong diurnal climatic conditions of the subalpine/alpine zone. This reproduction strategy is typical of epiphytic communities of xerophytic woodlands. The frequent change within the life strategy spectra of the different altitudinal zones indicates, that life strategies can be seen as a set of co-evolved adaptive traits, which grow and evolve within different taxa under similar ecological conditions.


2008 ◽  
Vol 24 (2) ◽  
pp. 121-133 ◽  
Author(s):  
Satomi Shiodera ◽  
Joeni S. Rahajoe ◽  
Takashi Kohyama

Abstract:The relationship between leaf longevity and other leaf traits was compared among different life-form categories (trees, herbs, climbers and epiphytes) of 101 plant species in a tropical montane forest on Mt. Halimun, West Java, Indonesia. We applied the Cox proportional hazards regression to estimate the leaf longevity of each species from 30 mo of census data. We examined whether estimated longevity was explained by either species life-form categories, taxonomic groupings (eudicots, monocots, magnoliids and chloranthales, and ferns) or such leaf traits as leaf area, leaf mass per area (LMA), mass-based leaf nitrogen, penetrometer reading, condensed-tannin-free total phenolics and condensed tannin. There was a wide-ranged interspecific variation in leaf longevity, mostly 10–50 mo, similarly across life-form categories. LMA showed a strong positive influence on leaf longevity. We found that relationships between leaf longevity and some leaf traits were different among various life forms. Trees tended to have high LMA, while climbers tended to have low LMA at the same leaf longevity. We hypothesize that such difference among life forms reflects shoot architecture characteristics. Multi-shoot trees with branching architecture need to have self-supporting leaves, whereas semi-epiphytic climbers can maintain relatively low biomass investment to leaves hanging or relying upon the mechanical support from host plants.


2021 ◽  
Vol 2 (1) ◽  
pp. 61-80
Author(s):  
Grace Cheng-Ying Lin

In Taiwan, abortion was legalized in 1984. This paper examines the voices surrounding abortion expressed by monasteries in Humanistic Buddhism, a prominent Buddhist philosophy practiced in modern Taiwan. Humanistic Buddhism emphasizes that it is a “religion of the people.” However, in addition to the law of karma and causality, the value of all life forms is prioritized based on the ethics of “non-harming (ahimsā).” When some monasteries insist that abortion is killing, resulting in karmic retribution, some express sympathy with a woman’s decision to abort. When some monasteries promote a newly popularized ritual to appease aborted fetuses, some are keenly critical of the exploitation of women and manipulation of scriptures. Through a discursive analysis, this paper demonstrates the wide spectrum of Buddhist narratives in response to reproductive politics embedded in the conflicts between modernity and tradition, as well as locality and globality.


Author(s):  
Pavlova N.R. ◽  
Dzerkal V.M. ◽  
Ponomareva А.А.

In order to preserve, reproduce and effectively use the natural complexes and objects of the DniproDelta as one of the most valuable natural floodplain-littoral complexes in Europe, which have special environmental, recreational, historical and cultural, scientific, educational and aesthetic value, and ensurethe conservationof «DniproDelta»wetland of theinternational importance,the National Natural Park «Lower Dnipro»was created(Decree of the President of Ukraine of November 24, 2015 No 657/2015).The flora of the higher vascular plants of the Park contains 820 species, 40 species of which (4.9% of the total number) are woody plants. Rosaceae Juss. (14 species), Salicaceae Mirb. (7 species), Aceraceae Juss. (3 types) are leading families of the dendroflora of the Park.Biomorphological characteristics of tree plant species in the flora of the Lower Dnipro National Nature Park were carried out according to the following classifications: 1) K. Raunkiersystem of plant life forms; 2) ecological and morphological classification of life forms of I. G. Serebryakov; 3) architectural models of F. Alle, R. Oldeman and P. Tomlinson; 4) classification of the life forms of plants of the temperate zone, which takes into account the vegetative propagation by O. V. Smirnova, L. B. Zaugolnova.AnalysisoftypesofbiomorphsaccordingtotheclassificationofK. Raunkiershowedthatthevastmajorityofdendrofloraspeciesbelongtophanerophytes, amongthem, dependingontheheightoftheplant, therearedifferentgroups-megaphanerophytes(e.g., Populustremula), mesophanerophytes(Salixalba), microphaneorphytes, nanophanerophytes(Amygdalusnana) andhamephytes(Ephedradistachia).According to the ecological and morphological classification of I. G. Serebryakov life forms, the flora of the Park is dominated by forest-steppe trees and forest-type trees.The trees which belong to one life form often differ in the principles of growth and formation of the crown, branching, and general habitus, which is generally considered as an architectural model of a particular species. According to the classification of architectural models by F. Alle, R. Oldeman and P. Tomlinson, in the flora of the Park, there are five models among which the species formed by the model of Tomlinson have a significant representation, and the species formed by the models of Manzheno and Champagne have a smaller representation.Key words:flora, tree, classification, life form, bush. З метою збереження, відтворення і ефективного використання природних комплексів та об’єктів дельти річки Дніпро як одного з найцінніших природних заплавно-літоральних комплексів у Європі, які мають особливу природоохоронну, оздоровчу, історико-культурну, наукову, освітню та естетичну цінність, забезпечення збереження водно-болотного угіддя міжнародного значення «Дельта р. Дніпро» створено Національний природний парк «Нижньодніпровський» (Указ президента України від 24 листопада 2015 року No 657/2015).Флора вищих судинних рослин Парку попередньо складає 820 видів, з них 40 видів (4,9% від загальної кількості) –деревні рослини.Провідні родини дендрофлори Парку –Rosaceae Juss. (14 видів), SalicaceaeMirb. (7 видів), AceraceaeJuss. (3 види). Біоморфологічну характеристику видів деревних рослин у флорі національного природнього парку «Нижньодніпровський» проведено за класифікаціями: 1) система життєвих форм рослин К. Раункієра; 2) еколого-морфологічна класифікація життєвих форм І. Г. Сєрєбрякова; 3) архітектурні моделі Ф. Аллє, Р. Ольдемана і П. Томлінсона; 4)класифікація життєвих форм рослин помірної зони, яка враховує вегетативне розмноження О. В. Смирнової, Л. Б. Заугольнової.Аналіз типів біоморф за класифікацією К. Раункієра показав, що переважна більшість видів дендрофлори належить до фанерофітів, серед них, в залежності від висоти рослини, виділяють різні групи –мегафанерофіти (наприклад, Populus tremula), мезофанерофіти (Salix alba), мікрофанерофіти (Amorpha fruticosa), нанофанерофіти (Amygdalus nana) та хамефіти (Ephedra distachia).За еколого-морфологічною класифікацією життєвих форм І. Г. Сєрєбрякова у флорі Парку домінують дерева лісостепового типу та дерева лісового типу.Дерева, які відносяться до однієї життєвої форми, часто відрізняютьсяпринципами наростання та формування крони, галуженням, загальним габітусом, що загалом розглядається як архітектурна модель конкретного виду. За класифікацією архітектурних моделей Ф.Аллє, Р. Ольдемана і П. Томлінсона у флорі Парку виділено п’ять моделей, серед яких, значне представництво мають види, що формуються за моделлю Томлінсона, менше представництво мають види, що формуються за моделями Манжено та Шампанії.Ключові слова: флора, дерево, класифікація, життєва форма, кущ.


2004 ◽  
Vol 64 (2) ◽  
pp. 201-209 ◽  
Author(s):  
M. A. Batalha ◽  
F. R. Martins

We used Raunkiaer's system to classify in life-forms the vascular plants present in 12 random 25 m² quadrats of a cerrado site. The study area is covered by cerrado sensu stricto and is located in the Valério fragment, at about 22º13'S and 47º51'W, 760 m above sea level, in the Itirapina Ecological and Experimental Station, São Paulo State, southeastern Brazil. The floristic spectrum considers the life-form of each species, while in the frequency spectrum, each species is weighted by its frequency. The vegetation spectrum does not consider the species at all, but only the individuals in each life-form class. In the floristic spectrum, the most represented life-forms were the phanerophytes and the hemicryptophytes, as in other cerrado sites. This spectrum differed significantly from Raunkiaer's normal spectrum, mainly due to under-representation of therophytes and over-representation of phanerophytes. The floristic and frequency spectra were similar, but both differed from the vegetation spectrum. We recommend the floristic spectrum when working at larger scales and a description of the phytoclimate is wanted. The vegetation spectrum is preferable when working at smaller scales and wanting a quantitative description of the physiognomy. The frequency spectrum is not recommended at all.


2021 ◽  
Author(s):  
Genda Singh ◽  
Bilas Singh

Abstract Background: Plants adapt to adverse environmental conditions accumulate varying concentrations of carbon (C), nitrogen (N) and sulfur (S) compounds to cope up with adverse climatic conditions. Carbon, N and S concentrations were determined in roots, stem and leaves of 33 species of trees/shrubs with objectives to observe the effects of life-form and plants functional traits, and select species with high concentration of these elements for their utilization in afforestation and medicinal uses. Results: Concentrations of C, N, and S and C: N and N: S ratio varied (P<0.05) between species, organs, life-forms and functional traits (legume vs non-legume). These variables were higher (except C in roots and stem) in trees than shrubs, and in leguminous than non-leguminous species. Non-leguminous species showed high S content and low N: S ratio. Antagonistic and synergistic relations were observed between C and N, and N and S concentration respectively. Species showed varying potential in assimilating carbon by regulating uptake and accumulation of these elements in different organs making them adapt to the habitats affected by drought and salinity. We observed strong plant size/life-form effects on C and N content and C: N and N: S ratios and of function on S content. Conclusions: Life-form/size and varying functions of the species determined C: nutrient ratio and elemental composition and helped adapting varying environmental stresses. This study assist in selecting species of high carbon, nitrogen and S content to utilize them in afforesting the areas affected by water and salt stresses, increased carbon storage and species with high S/N content in medicinal uses.


IAWA Journal ◽  
2006 ◽  
Vol 27 (4) ◽  
pp. 419-442 ◽  
Author(s):  
Fritz Hans Schweingruber

The xylem and phloem of Brassicaceae (116 and 82 species respectively) and the xylem of Resedaceae (8 species) from arid, subtropical and temperate regions in Western Europe and North America is described and analysed, compared with taxonomic classifications, and assigned to their ecological range. The xylem of different life forms (herbaceous plants, dwarf shrubs and shrubs) of both families consists of libriform fibres and short, narrow vessels that are 20–50 μm in diameter and have alternate vestured pits and simple perforations. The axial parenchyma is paratracheal and, in most species, the ray cells are exclusively upright or square. Very few Brassicaceae species have helical thickening on the vessel walls, and crystals in fibres. The xylem anatomy of Resedaceae is in general very similar to that of the Brassicaceae. Vestured pits occur only in one species of Resedaceae.Brassicaceae show clear ecological trends: annual rings are usually distinct, except in arid and subtropical lowland zones; semi-ring-porosity decreases from the alpine zone to the hill zone at lower altitude. Plants with numerous narrow vessels are mainly found in the alpine zone. Xylem without rays is mainly present in plants growing in the Alps, both at low and high altitudes. The reaction wood of the Brassicaceae consists primarily of thick-walled fibres, whereas that of the Resedaceae contains gelatinous fibres. The frequency of sclereids in Brassicaceae bark is an indicator of ecological differences: sclereids are rare in plants from the alpine zone and frequent in plants from all other ecotones.


2018 ◽  
Vol 96 (1) ◽  
pp. 138 ◽  
Author(s):  
Tatiana Lobato-de Magalhães ◽  
Mahinda Martínez

<p><strong>Background: </strong>Mexico has a high diversity of aquatic and subaquatic plants that occur between 1,000 and 2,500 m of elevation, although a larger proportion of aquatic plants is concentrated at lower altitudes. Temporary wetlands harbor close to 73 % of the aquatic species in Mexico. These systems are under a strong anthropogenic pressure and suffer constant degradation.</p><p><strong>Questions:</strong> i) How many species grow in highland temporary wetlands? ii) Are they floristically similar? iii) Is there a latitudinal pattern of species richness?</p><p><strong>Studied groups: </strong>Charophyta, Pteridophyta, Angiosperms.</p><p><strong>Study site and years of study:</strong> Central Mexico (39 wetlands) from 2015 to 2016.<strong></strong></p><p><strong>Methods: </strong>We collected in 39 temporary wetlands for two years. We made a presence/absence list of species per locality, and calculated floristic similarities and correlations between wetlands. We include data characterizing life form, plant use, and conservation status.</p><p><strong>Results:</strong> We found 126 species belonging to 80 genera and 38 families. The richest families were Cyperaceae, Asteraceae, and Poaceae. As to genera, <em>Eleocharis</em>, <em>Cyperus</em>, and <em>Juncus </em>had more species. Species with the widest distributions were <em>Persicaria mexicana</em>, <em>Marsilea mollis</em>, <em>Luziola fluitans</em>, <em>Heteranthera peduncularis</em>, and <em>Nymphoides fallax</em>.  We found five different life forms – all herbaceous, including 27 threatened species, 24 species with economic use, 48 endemic species, and 19 cosmopolitan species. In addition, we found 20 species recorded for the first time in some states included in our study, and two species of <em>Eleocharis</em> that might represent undescribed species. The richest wetland harbors 40 species, the poorest has only five. Wetlands were comparable to each other in species composition, and species richness increases towards the south.</p><p><strong>Conclusions:</strong> Temporary wetlands harbor a high floristic diversity and are similar to each other. Lower latitudes host higher numbers of species.</p>


We argue that there is a factor of at least 10 264 to somehow be accommodated to explain how it is possible that our universe produced a life-form with our advanced level of intelligence. The factor arises from an analytical development of the theme that very intelligent life-forms would give physical expression to a highly distinguished mathematical truth in a canonical way. This structure, which serves to flag the occurrence of a life-form possessing an advanced intelligence, is termed the canonical artefact (TCA). Using TCA we show that if the laws governing the universe’s evolution to the present are indifferent to the emergence of a life-form with advanced intelligence, then the chance of emergence is less than one part in 10 264 , and, if instead, the laws make the emergence a virtual certainty, then the emergence is greater than a 264 orders of magnitude effect. In the first case, emergence of a life-form with advanced intelligence is exceedingly unlikely, and, in the second case, where such a life-form is inevitable, physics faces the problem of giving even a semblance of a quantitative explanation for a 264 orders of magnitude effect. In either case physics is left with a puzzle: explain why our universe contains a life-form with advanced intelligence.


2008 ◽  
Vol 21 (4) ◽  
pp. 301 ◽  
Author(s):  
Núria Garcia-Jacas ◽  
Mercè Galbany-Casals ◽  
Kostyantyn Romashchenko ◽  
Alfonso Susanna

The limits of the genera that compose the Onopordum group of the Cardueae–Carduinae are difficult to establish. There are two main life forms; one is exemplified in the genus Onopordum, which includes only biennial colonisers in the Mediterranean region and temperate Eurasia; the second life form is exemplified in the group of perennial herbs of the genera Alfredia, Ancathia, Lamyropappus, Olgaea, Synurus, Syreitschikovia and Xanthopappus, all of them growing in the mountains of central Asia. We explored relationships among the genera of the complex by using Bayesian and parsimony analyses of a combined dataset of nuclear and plastid DNA sequences. Our results confirmed that the group is natural and the two life forms correspond to well defined entities. Generic limits within the eight central Asian genera are, however, very difficult to establish. Our results suggested that the present genus circumscription is artificial, especially for the largest genus, Olgaea, which appears paraphyletic. Some solutions are suggested. The most preferable might be lumping all small genera together in a broadly redefined genus Alfredia, and assigning sectional rank to the natural groups that result from correlating morphology with our molecular results. However, none of the possible solutions is free of problems because morphological characters and molecular phylogeny are not fully congruent. Some considerations on the origin and peculiar adaptations for becoming a successful coloniser shown by Onopordum are also offered, finding parallels to these adaptations in other examples of biennial colonisers within subtribe Carduinae.


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