Showing papers by "Jean Moulin University Lyon 3 published in 1993"

Nature, mass and preferential sites of coarse woody debris deposits in the lower ain valley (Mollon reach), France

Abstract: Coarse woody debris (CWD) has been examined in a section of the Ain, a sixth order piedmont river with an actively meandering channel and a wooded floodplain. The spatial distribution of CWD, its mass and forms of accumulation are controlled by the hydrodynamics and the retention capacity of the forest. A typology shows the relative importance of woody debris in the mosaic of patches and the essential role of the ecotonal zones. The mass of debris varies from 0001 t ha−1, to more than 200t ha−1, but is lower than those observed in certain American rivers. Most of the material is deposited in the margins and forms a narrow debris line. The restocking in woody debris is recent in Europe and tends to diversify the environment. This affects the researcher and the planner. The first considers this transit of material as a useful hydromorphodynamic and biodynamic tool which is easy to evaluate, and the second considers it as a restoring and generative vector, the ecological functions of which are recognized. Its effect is stronger today as the watershed area tends to be subjected to a decrease in agricultural activity.

Finite invariant simplices in infinite graphs

Abstract: It is shown that ifG is a graph which is contractible or dismantlable or finitely ball-Helly, and without infinite paths; or which is bounded, finitely ball-Helly and without infinite simplices then: (i) any contraction ofG stabilizes a finite simplex; and (ii)G contains a finite simplex which is invariant under any automorphism.

Le monde des morts en Gaule rurale à l'époque romaine. L'apport des textes littéraires et épigraphiques. [The world of death in rural Gaul during the roman period : the literary and epigraphic evidence ]

Abstract: Le recensement des sources litteraires et epigraphiques concernant les tombes dans le monde rural a l'epoque romaine montre de nombreuses insuffisances : beaucoup d'approximations concernant les localisations — dans le cas des sources litteraires — peu de renseignements lorsqu'il s'agit de textes epigraphiques. Ces derniers sont cependant les plus nombreux et leur apport concerne le vocabulaire de la tombe, sa localisation et l'existence ou non d'un enclos. Le droit de la tombe est l'aspect le plus souvent aborde : l'existence d'un testament etabli par le defunt (ex testamento, testamento poni iussit, iussus ab eo...) ou d'une ceremonie anniversaire. En somme, c'est principalement le souci de conservation de la memoire du mort que l'on a cherche a mettre en evidence.