bluuebunny/crossref_metadata_2025_split huggingface dataset:
Structure, productivité et régime hydrique de phytocénoses halophiles sous climat méditerranéen
Authors: Berger André , Corre Jean-Jacques , Heim G. 
Published: November 2022

Des recherches sur le régime hydrique de la couverture végétale (potentiel hydrique et transpiration), les variations de la biomasse végétale (matière sèche, composition chimique et valeur énergétique) et la production primaire ont été effectuées parallèlement à une étude de la composition floristique, de la salinité et de la profondeur de la nappe phréatique le long d’un transect implanté dans une végétation halophile dominée par Salicornia fruticosa et Arthrocnemum glaucum.
Les biomasses végétales se sont avérées relativement élevées dans le Salicornietum fruticosae : de l’ordre de 3 kg de matière sèche par m2, alors qu’elles n’atteignent que 0,4 kg m-2 dans l'Arthrocnemetum. L’analyse des variations saisonnières de cette biomasse a permis de situer la production primaire annuelle du Salicornietum fruticosae entre 0,5 et 1 kg de matière sèche par m2, correspondant à un équivalent énergétique de 8-16 MJ m— 2, pour un rayonnement global incident de l’ordre de 6000 MJ par an. Sans atteindre les valeurs élevées qui caractérisent les marais d’eau douce ou les cultures, elle est du même ordre de grandeur que celle d’un peuplement de Quercus ilex étudié sous le même climat.
La zone étudiée est caractérisée par la présence d’une nappe phréatique salée (10-45 g 1—1) présentant des oscillations saisonnières de niveau. A une période de submersion hivernale, au cours de laquelle il y a des risques d’asphyxie des racines, succède un assèchement, puis un abaissement de la nappe qui descend jusqu’à environ 70 cm dans le courant de l’été. Cet abaissement se manifeste par une chute du potentiel hydrique dans la vascularisation et par une régulation de la transpiration ; parallèlement on observe un ralentissement très net de la croissance, qui fait que la production primaire est réalisée, pour l’essentiel, en trois mois (mai à juillet).
La comparaison de deux zones se distinguant par la salinité de la nappe et le mode d’enracinement a montré la complexité et la nature de certaines relations entre les fluctuations de salinité et de profondeur de la nappe, l’évolution du régime hydrique de la plante et les variations de la biomasse. La répartition des racines en plusieurs strates joue un rôle important dans le maintien du potentiel hydrique de la plante. La présence d’une strate profonde lui permet, en été, de s’affranchir des horizons superficiels, où viennent s’accumuler les sels, et de garder le contact avec la frange capillaire. La présence d’une strate superficielle lui permet, au début de son cycle végétatif, d’éviter l’asphyxie lorsque la nappe est encore proche de la surface.
La nématofaune de quelques écosystèmes forestiers du Mont Ventoux
Authors: Scotto la Massèse Claude , Du Merle Paul 
Published: November 2022

Soil samples were taken in clearings, the forest edge and in the surrounding woodland ; three horizons were distinguished in each sample. Samples were analysed by centrifugal flotation. Nematodes were divided into five groups (based on their mode of feeding) : saprophages, mycophages, phytophages, predators and “others” (whose diet is unknown). 107 species were identified, distributed among 71 genera : most of the species (76) were phytophagous. The richness of the fauna varied between sites, but was independant of altitude. The richness of the phytophygous, mycophagous and predator groups was correlated with the depth of sampling. The richness of the total fauna, the phytophages and the mycophages decreased on passing from a clearing to the surrounding forest.
The saprophages occurred at the highest densities (making up 76 % of the whole collection). Density was independant of altitude. The density of the total fauna, the mycophages and the saprophages was correlated with the depth of sampling. The density of the total fauna, the saprophages and the mycophages also changed on passing from a clearing to the surrounding forest.
The areas replanted with exotic species (Cedrus atlantica and Pinus nigra) sometimes differ from those under native forest or replanted with native trees in that the richness and density of phytophages strongly decrease on passing from the clearings to the forest.
L’«Opération Éléphants » au Rwanda — 2e partie. Acclimatation et régime des jeunes éléphants introduits dans le parc national de l’Akagera
Authors: Monfort Nicole , Monfort Alain 
Published: November 2022

In 1975, twenty-six calves and immature elephants were captured in southern Rwanda and relocated in the Akagera National Park in northeastern Rwanda, where no elephants had been sighted for some decades. This paper is a preliminary report on the adaptation of these elephants to their new environment. The young elephants belonged to different family units but, in their new habitat, they formed stable social herds. During the study period, they remained on a 1200 ha home range on a peninsula in the large swampy depression of the Akagera River.
Food habits were studied by direct and indirect observations. Eighty plant species were found to be eaten, and 3071 recorded observations were analysed. There were marked seasonal changes in the diet. The elephants did not seem to be affected by undernutrition in the dry seasons. Creepers, trees, shrubs, and swampy herbs and grasses were abundant and dominant in the diet. Grazing increased at the beginning of wet seasons when food plants were richest in nutritive value. Most of the grasses were avoided at the end of the rains and in dry seasons. The impact of browsing and grazing was most marked in the riverine vegetation utilized intensively all the year round, where some plants, such as Sesbania sesban, were heavily damaged. In the savanna woodland, the vegetation was only lightly damaged. The impact of browsing on the vegetation, was usually compensated by plant growth, but browsing nevertheless affected the stature of some plants.
Ecological succession in the Akagera Park seems to evolve towards a natural reforestation and the clearings made by a small population of elephants might be beneficial for most grazing animals. The possibilities of local competition between elephant and buffalo for some swampy and riverine pastures during drought periods are evoked.
Conséquences comportementales de perturbations sociales répétées sur une troupe de Mones de Lowe Cercopithecus campbelli lowei de Côte-d’Ivoire.
Authors: Galat-Luong Anh , Galat Gérard 
Published: November 2022

New observations have been made on the troop of Mona monkeys previously studied at Adiopodoumé, Ivory Coast, by Bourlière et al. (1969-70) and Hunkeler et al. (1972).
Following repeated poaching episodes, a young male leader took over the control of the residual troop in 1977. During this take over, the new male leader became very aggressive at the time the females gave birth (August and September). All of them were seriously hurt, together with their young infants which subsequently died. Such a behaviour suggest deliberate infanticide.
A depressive syndrome has also been observed in a peripheral isolated subadult male, including auto-aggression.
Socio-écologie du Skua antarctique à Pointe Géologie
Authors: Jouventin Pierre , Guillotin Michel 
Published: November 2022

Le statut taxonomique du Skua est discuté. La distribution géographique circum-antarctique de l’espèce, sa taille plus petite que celle des autres Skuas, sa coloration plus claire, sa voix beaucoup plus aiguë et la quasi-absence d’hybridation nous paraissent bien confirmer une place à part.
Les données de terrain et celles obtenues à partir du fichier de baguage, qui couvre aujourd’hui 15 années, permettent de préciser certains aspects de la biologie de cette espèce : migration, dimorphisme sexuel, longévité, fidélité au nid et au partenaire, ainsi que leur valeur de survie.
Les Skuas sont des oiseaux opportunistes par exellence puisqu’ils sont à la fois pêcheurs, rapaces et charognards. C’est ce dernier aspect qui est à l’origine de l’expérience naturelle qui a été réalisée involontairement sur la population de Pointe Géologie. Au cours des vingt dernières années, les déchets de la base française de Terre Adélie ont constitué un apport de nourriture qui a provoqué un essor de la population de Skuas de l’archipel. La population globale a quadruplé (80 en 1964 à 320 en 1977), le nombre de couples reproducteurs a presque doublé de l’été austral 1964/1965 à celui de 1976/1977. En conséquence, la distance entre les nids est tombée de 110 mètres en 1965 à 65 mètres en 1976.
La fécondité est passée de 44 œufs pondus en 1965/1966 à 63 en 1976/1977. Par contre, la mortalité au stade des œufs a augmenté de 18 % en 12 ans. Cette relation entre densité et mortalité explique que le nombre de poussins à l’envol s’est maintenu de 1964/1965 à 1976/1977.
La ponte qui est de deux œufs a toujours étonné les auteurs antérieurs qui se demandaient pourquoi un seul poussin par nid arrive généralement à s’envoler. Or, en pleine période d’expansion de la population (1965/1966) les deux poussins achevaient généralement leur croissance (9 sur 10) alors qu’actuellement et à nouveau, seul un poussin survit par nid. De plus les Skuas qui, il y a 10 ans, étaient constamment vus en train d’attaquer les poussins de Manchots Adélie ne le font plus qu’exceptionnellement aujourd’hui.
Il semble que lors de l’installation de la base, la population de Skuas de Pointe Géologie ait été en équilibre avec les ressources naturelles. L’apport de la décharge a permis un accroissement rapide de la population et a mis en évidence la signification biologique de l’existence d’un deuxième poussin qui n’arrivait pas à survivre.
La population reproductrice suivit avec quelque retard la population globale par suite du facteur limitant qu’a dû devenir la surface des îlots rocheux. La source principale d’alimentation n’étant plus le Manchot Adélie, le cycle reproducteur du Skua s’est complètement désynchronisé de celui-ci (des pontes de remplacement apparaissent maintenant un mois et demi après les dernières observées il y a une dizaine d’années). Aujourd’hui, la population de Skuas semble à nouveau en équilibre avec les ressources alimentaires, aussi bien naturelles qu’artificielles, aussi est-il rare de voir survivre le deuxième poussin.
Chapitre premier. Édification de la Camargue et histoire holocène de sa végétation
Authors: Pons Armand , Toni Claude , Triat Hélène 
Published: November 2022

The history and past vegetation of the Camargue during the last 11,000 years have been reconstructed on the basis of the pollen analysis of cores from two bore holes, one 42 m deep in the southern part of the delta, and another 13 m deep in northern Camargue.
The holocene history of the delta is well in agreement with that of the surrounding areas. The edaphic vegetation has never completely covered what now constitutes the Camargue. The pollen analysis indicates that from 5300 BP, the present alluvial flat landscape was almost completely settled by man. It also shows that salt production and agriculture were practiced simul¬ taneously in the most recent phases of the history of the delta. The sequence of onlaps and offlaps since the Flandrian epoch is shown on a series of maps and diagrams.
Chapitre 9. Recherche sur l’évolution du comportement alimentaire et de la structure sociale d’un groupe de chevaux camarguais
Authors: Sereni J.L. 
Published: November 2022

The social organisation and feeding habits of a small group of Camargue horses (one stallion and seven mares) have been studied in the “sansouire”.
With respect to feeding behaviour, it was found that some plants were eaten over long periods of time, e.g. Scirpus maritimus, Phragmites communis, Juncus maritimus, Juncus subulatus and grasses. Other species were used only during one season, Aeluropus littoralis in summer and Obione portulacoides in autumn. The same plant could be taken from various plant communities. Within the same community one species can be eaten during one season and another species during another season.
In summer, resting and feeding areas were segregated. This did not occur during the rainy season, when the “sansouire” was flooded.
During the first period of the study, the development and stabilisation of dominance-subordination relationships, and of affinity bonds, were examined. A linear dominance hierarchy rapidly developped.
Within this small group, the social roles of different individuals were established. The dominant mare was not the leader. Usually the stallion dominated all the mares. When the group was on the move, the stallion was typically last, following the females.
Le Hérisson (Erinaceus europaeus L.) et la route
Authors: Berthoud Guy 
Published: November 2022

Between 1964 and 1978, 3452 hedgehogs were killed by traffic on motorways and on some roads in the french speaking part of Switzerland.
Observations of these animals have allowed the determination of the periods, weather conditions and places most favourable to their movements.
The following points have been established :
1. In the spring, the majority of hedgehogs move between their winter and summer quarters.
2. The males frequently travel between March and July, their rutting period.
3. The females often travel just before giving birth.
4. Subadults disperse massively in early spring.
5. A number of the young hedgehogs disperse during autumn.
6. The majority of these movements occur when weather conditions change, at the end of a period of high pressure and north wind. 7. Urban areas are more densely populated by hedgehogs than forest or agricultural areas.
8. The outskirts of towns, as well as forest borders, rivers and hedges play an important role in the selection of their routes.
We have concluded that hedgehogs can be protected along roads by creating and maintaining favorable conditions which enable them to move freely. When planning a road, an area, or a farm land redistribution scheme, the conservation or replanting of hedges, for example, would play an essential role in protecting hedgehog populations.
Estimation des dégâts causés par les oiseaux aux céréales en Algérie
Authors: Metzmacher Maxime , Dubois Daniel 
Published: November 2022

En 1977 une méthode d’échantillonnage a été expérimentée pour estimer les dégâts d’oiseaux aux céréales (orge, blé dur) du nord-ouest de l’Algérie.
La distribution des dommages a été analysée en fonction de la présence de colonies de Moineaux espagnols. Les informations recueillies indiquent que les oiseaux préfèrent certains champs et, à l’intérieur de ceux-ci, certains épis à d’autres. Les raisons en sont discutées.
Les résultats apportent aussi un moyen de simplifier la méthode de sondage.
Poids des nouveau-nés et stratégies reproductrices des vipères européennes
Authors: Saint Girons H. , Naulleau G. 
Published: November 2022

The reproductive strategies of six species and two subspecies of European vipers are compared. Eighty eight clutches were examined.
The reproductive effort, defined as the ratio of total litter weight over body weight of the female just after parturition, varies widely among individuals. This individual variation is in part due to the variable amount of fat accumulated by pregnant females during vitellogenesis, and therefore is associated with their nutrition during the gestation period. However, a genetic polymorphism cannot be ruled out in certain populations. The average reproductive effort of the various species studied is 0.476 ; it does not significantly differ between the species concerned.
Among the taxa studied, the average female body weight, just after parturition, ranges from 12.1 to 139.0 g, whereas that of the neonates ranges from 2.74 to 7.4 g, and their number from 2.0 to 8.9 per litter. Therefore the variation in neonatal body weight is smaller than that of the number of newborn per litter. Broadly speaking, small viper species bear fewer offsprings than larger ones, but these offspring are proportionately bigger.
The distribution of the reproductive effort not only varies with the body size of the individual adult female ; it also depends on the species concerned, more particularly on the feeding habits and feeding opportunities of the newborn. Those which feed on invertebrates and, to a lesser extent, on small lizards, can afford to be small and numerous. This is not the case for the species whose young feed mostly on small mammals.
Within a given taxon, the size of a litter generally increases with the body weight of the mother, whereas there is no correlation between the individual body weight of the newborn and that of their mother. The mortality rate of the young vipers during their first ten months of life varies greatly within the species concerned, at least in captivity. However, within a given species, the larger the newborn, the lower the mortality rate.
In conclusion, the individual body weight of the newborn, and the variability of the reproductive effort among the various species of European vipers studied, depend on a number of different factors : female body size, feeding habits of the newborn, availability of prey, and mortality rates of the young in the postnatal period. The values observed under natural conditions obviously result from a compromise between different and often conflicting selective pressures.
Influence de l’environnement sur les composantes du groupe social chez le Daim Cervus (Dama) dama L.
Authors: Schaal A. 
Published: November 2022

The patterns of social grouping of free ranging fallow deer, Cervus (Dama) dama, have been studied outside the breeding season for two consecutive years, in Alsace (N.E. France).
Comparisons are made between animals living in a forest environment (HF animals) and others living in a more open habitat (HO animals), as well as with fallow deer inhabiting an intermediate, semi-closed environment (HI animals). Group characteristics are compared : occurence of the various grouping patterns (including solitary individuals), group size and composition, stability of social groups, and intra-group spacing.
The composition of social groups varies greatly within a given population, depending upon the environmental conditions. All female groups are the most frequently observed in both forest and open habitats, whereas heterosexual groups rank a close second in open areas. Solitary animals are more frequently seen in forest environments than in open ones (Table I). The average overall group size is larger in open habitats (Table II). Group composition is also less stable, and group splitting more frequent, in open environments (Table III). Inter-individual distances between females are greater in forest habitats.
Survie en milieu insulaire : quelle stratégie? Le cas des mésanges en Corse
Authors: Michelland Dominique 
Published: November 2022

The breeding biology and demography of Blue tit (Parus caeruleus) and Coal tit (Parus ater) populations of southern France and Corsica were compared from 1976 to 1980. The following differences between the mainland and the island populations were found :
1. — The onset of the breeding season is delayed in Corsica, egg-laying beginning three to four weeks later than on the mainland.
2. — The clutch-size is smaller on the island, the clutch averaging three more eggs on the mainland. 3. — The mortality of the nestlings is also much higher in Corsica than in southern France, due to heavy parasitism by Trypocalliphora sp. and food shortage which cause heavy mortality.
4. — However, the survival rate of adult tits is higher in Corsica than on the mainland.
5. — Contrary to what is the rule in southern France, Corsican tits do not apparently breed at the time of maximum food abundance.
The demographic strategies of the Corsican populations of Blue and Coal tits are apparently K-selected.
Etude du comportement de prédation du Martin-pêcheur Alcedo atthis (L.) : taille préférentielle de capture du Chabot Cottus gobio (L.) et de la Truite Salmo trutta L.
Authors: Hallet-Libois C. 
Published: November 2022

Prey size selection by the European kingfisher Alcedo atthis has been studied from 1975 to 1977 in a breeding population along the Lesse River, Relgium.
The size of the fish taken changes with age of the nestlings. During the first ten days of the rearing period fish of a small size are caught more frequently than large ones. On the other hand, larger fish are caught and brought back to the nest as soon as the fledglings are able to ingest them.
The portion of the fish population preyed upon by kingfishers has also been identified. Fry is caught as soon as it reaches 1.5 to 2.0 cm in length ; larger fry (up to 4 cm long) is only actively saught during the rearing period of young nestlings. Fish 4 to 7 cm long are the most frequently preyed upon, the largest ones measuring 10 cm long.
Structure d’une communauté de Carnivores dans la Cordillère Cantabrique occidentale
Authors: Guitian Rivera José , Callejo Rey Antonio 
Published: November 2022

L’étude analyse des aspects déterminés de la structure d’une communauté de mammifères Carnivores dans la Cordillère Cantabrique Occidentale (Galice Orientale, Espagne), à partir de données provenant de l’analyse d’excréments et de contenus stomacaux. La communauté étudiée se compose de 8 espèces : le Loup (Canis lupus), le Renard (Vulpes vulpes), le Blaireau (Meles meles), la Loutre (Lutra lutra), la Belette (Mustela nivalis), la Martre (Martes martes), la Genette (Genetta genetta) et le Chat sauvage (Felis sylvestris).
Au moyen du calcul des valeurs de largeur et de chevauchement de la niche trophique, on constate que le fonctionnement de la communauté est facilité par une nette spécialisation des espèces. Les différences de taille sont également responsables des préférences montrées par chaque prédateur pour la taille de ses proies habituelles. Une analyse en composantes principales fait apparaître, à partir d’une série d’indices qui résument l’information fournie par les régimes alimentaires, les facteurs les plus importants facilitant la coexistence entre les Carnivores de la communauté. Les variables les plus déterminantes sont : l’utilisation de l’habitat, le choix des proies et parfois la tactique de chasse. La figure 2 situe chacune des espèces par rapport aux trois axes principaux (75,7 % de la variance totale).
Pour terminer, les particularités structurelles de la communauté pouvant résulter du caractère saisonnier du milieu et donc de ses ressources, comme de l’hétérogénéité de la région et de ses particularités faunistiques, sont discutées.
Les fruits et les graines des espèces végétales pionnières de Guyane Française
Authors: Prévost M.F. 
Published: November 2022

Quantitative data are provided on the fruits and seeds of 90 pioneer species of plants characteristic of the young secondary forests in French Guyana : size of the fruits, number of seeds per fruit, size of the seeds. The dispersal mechanisms of the species are described.
Most pioneer species produce berries (51/90), drupes (15/90) or capsules (13/90). The greatest diameter of most (72 %) of the fruits is less than 2 cm ; 60 per cent of the fruits contain more than 50 seeds each, and the greatest diameter of 84 per cent of the seeds is smaller than 5 mm. The seeds of most species (93 %) are dispersed by animals.
The variation of the number of seeds per fruit was studied in 11 species of Solanum and two Passiflora ; the number can vary by a factor of two to four.
The production of seeds per individual plant was estimated in the short-lived pioneer Solarium rugosum ; it can reach 2.3 millions of seeds per individual plant during its average life-span of 4 years.