Ecological and evolutional principles of arid fodder plants selection are discussed. The importance of the following fundamental principles of ecology - the concept of plant life strategical types and the concept of polytypic character of species
Rainfall interception and splash detachment with a Brussels sprouts plant: a laboratory simulation
, are determined without a plant cover and with the cover of a single Brussels sprouts plant. The detachment rate was found rather surprisingly to be inversely related to the energy of the rainfall under the plant and positively related to the number of leaves.
Two types of plants (Trifolium pratense L. and Lolium multiflorum Lamk.) were grown in pots either separately, with one or two similar plants or together with one plant of each species. The use of labelled nitrogen N gives the proportion
of assimiled and (or) fixed nitrogen. Concurrence for N-nutrition is observed in monoculture for clover as well as for ryegrass. We confirm the order of N-mobilised quantities by plant: plant alone, two mixed plants, two similar plants. In association
La conservation génétique des plantes sauvages. Pour la conservation in situ des ressources génétiques des plantes cultivées
Conservation des espèces ; Géographie physique ; Plante cultivée ; Protection de la nature ; Ressource génétique ; Ressource naturelle
Les AA. expliquent pourquoi il est important de conserver les plantes sauvages apparentées aux expèces cultivées (pomme de terre, coton, maïs, tomate, café)| comment on peut utiliser leur matériel génétique pour obtenir des espèces cultivées plus
A negative correlation is shown to exist between the frequencies of occurrence of tannins and alkaloids among the major orders and families of Dicotyledons (and other Spermatophytes as well). Tannins and alkaloids are both used by plants
to discourage consumption by animal consumers. Two phytochemical tactics can be identified: (1) the T-tactic, based on the mass use of molecules (tannins and terpenoids) which influence the palatability and digestibility of plant material, and (2) the a-tactic
, based on the use of various toxic micromolecules, often nitrogenous, present at low concentrations in plant tissues, such as alkaloids, nonproteic amino-acids, cyanogenic glycosides, glycosinolates, etc. T-tacticians are generally found among K
-strategists, i.e. plant species growing in stable and predictable environments, mostly forests. On the other hand, a-tacticians are mostly found among r-strategists, i.e. plants living in unstable and marginal environments, more particularly those
Nurse plant relationships of columnar cacti in Arizona
Patterns of association of three columnar cactus species with potential nurse plants and rocks are examined in Organ Pipe Cactus National Monument, Arizona. The results suggest that a landscape scale, population dynamics of columnar cacti are more
Soil compaction and water uptake of plants in Impact of water and external forces on soil structure. Selected papers of the 1st Workshop on soilphysics and soilmechanics, Hannover 1986.
This paper describes a method for studying the influence of soil compaction and soil structure on the water uptake of plants under controlled conditions.
Post-eruption erosion processes and plant recovery in the summit atrio of Mt. Usu, Japan
The present study is primarily concerned with rilling and gullying and their linkages with plant recovery in the atrio. Surficial slope erosion in relation to revegetation is studied on the basis of field examination and aerial photo interpretation
Ekotipy rastenij i ih znacenie dlja introdukcii pustynnyh kormovyh kul'tur (Ecotypes de plantes, leur importance pour l'introduction de cultures fourragères de région aride)
Characterization and classification of tidal marsh soils and plant communities in north-west Spain
The objective of this research is the characterization and classification of soils and plant communities in a tidal marsh in the Ria of Betanzos (43o21'N, 8o13'W) as a contribution to the knowledge of the specific properties of these soils which
The concept Common species exemplified from records of vascular plants in the Ganla valley area in Sor-Trondelag, Norway in (Mélanges en l'honneur d'Ilmari Hustich).
Effective mutualism between sequentially flowering plant species
La succession dans le temps de la floraison chez des plantes qui se partagent les mêmes pollinisateurs est due à la compétition, mais elle correspond à un mutualisme de fait en ce qu'elle est nécessaire au maintien de la population de pollinisateurs
Adaptativnaja evoljucija anatomiceskogo stroenija pustynnyh rastenij Evolution et adaptation de la structure anatomique des plantes désertiques
Adaptative peculiarities of vegetative and generative organs of 68 species from 30 genera of Chenopodiaceae are brought to light. Many of these plants are valuable food plants, dominants of desert pastures. A scheme of structural and functional
Influence of frost heaving on soil chemistry and on the distribution of plant growth forms
La végétation sur les sols gelés est influencée par deux facteurs principaux : les effets de rupture sur les parties de la plante à l'intérieur du sol gelé et une disponibilité accrue en nutriments, une augmentation du pH et de la saturation en
bases. Effets sur la répartition des formes de croissance des plantes.
Croissance des plantes en sous-bois de forêt dense humide (Makokou, Gabon)
The growth of tree saplings, juvenile lianas and understorey shrubs was studied in a rain forest of north-east Gabon from 1980 to 1985. Five hundred individual plants belonging to more than one hundred species were marked along two transects, one
located in side the undisturbed forest and the other in a recent tree gap. The mortality of these plants during the 64 months' time interval, the growth in height, the percentage occurrence of traumas and the average leaf lifespan, were measured.
subtances involved in the arms race between plant producers and animal consumers, the evolutionary mechanisms implied in coevolution, the costs and benefits of the alternative adaptive strategies adopted by insect consumers (with particular emphasis