L’Avifaune nidificatrice d’une forêt de chênes pédoncules en bourgogne : étude de deux successions écologiques

Deux types de successions écologiques se développent cycli quement dans les massifs forestiers du Querceto Carpinetum primuletosum de Bourgogne selon l’exploitation forestière en Futaie ou en Taillis-sous-futaie. Nous avons dénombré pendant 9 ans les Passereaux, Picidés et Colombidés nichant dans les divers stades évolutifs des deux successions. Les dénombrements furent effectués par la méthode des IKA couplée avec celle des plans quadrillés, sur 185 échantillons répartis au sein de quelques grands massifs représentent une surface de 6 000 hectares de biotope homogène. 1) Les espèces nicheuses sont, pour la plupart, extrêmement sensibles à la physionomie du peuplement végétal, telle que la déterminent le mode d’exploitation et l’âge de la forêt, à tel point que peu d’entre elles se montrent capables d’habiter une succession d’un bout à l’autre de son évolution. 2) Les dénombrements spécifiques nous montrent des espèces qui ont un preferendum temporaire à un des stades évolutifs et d’autres qui augmentent progressivement jusqu’au climax. Au sein de chaque groupe phvlétique on voit comment les espèces évitent la concurrence en ayant soit des optimums différents soit des limites de tolérances différentes. 3) Beaucoup d’espèces montrent ainsi une préférence pour les jeunes stades initiaux buissonnants (phase à Sylviidés domi nants) et beaucoup d’autres pour les vieux boisements sub-clima- ciques (phase à Paridés dominants), mais très peu trouvent leur optimum dans les hauts buissons ou perchis intermédiaires. 4) Ces préférences spécifiques font que l’abondance totale de l’avifaune évolue selon une courbe à deux maximums séparés par un minimum. Ces deux maximums sont dus respectivement à une avifaune exogène , qui a pu pénétrer nos régions récemment à la suite des défrichements et qui conserve un caractère migra teur, et à Y avifaune endogène sédentaire qui a évolué sur place dans le climax des forêts étudiées. Les stades intermédiaires, créés artificiellement par l’homme, sont trops récents et éphé mères pour avoir permis l’adaptation d’une faune qui leur soit propre et ne conviennent bien à aucune des deux autres faunes. 5) Le nombre d’espèces nicheuses évolue parallèlement à l’abondance totale et il y a une corrélation positive très étroite entre ces deux caractéristiques des avifaunes. 6) La taille moyenne des oiseaux nicheurs augmente du début à la fin des successions. 7) Les avifaunes des deux successions, très différentes au début, montrent de plus en plus de points communs au cours de leur évolution jusqu’à se trouver presque identiques aux derniers stades, où elles représentent une avifaune probablement voisine de celle du climax. 8) Le facteur essentiel de l’abondance totale semble être l 'hétérogénéité du peuplement végétal ; les stades les plus riches en biomasse sont ceux où la physionomie du peuplement est la plus variée, et notamment ceux qui sont capables d’attirer des espèces appartenant aux deux avifaunes précitées. 9) Le sub-climax n’est pas le stade d’abondance ni de diver sité maximales. Par contre, c’est le stade où la taille moyenne des oiseaux est la plus forte et où l’avifaune est la plus sédentaire.Two types of ecological successions develop in semi-natural Quercus pedunculata forests in Burgundy, depending on the type of forestry management undertaken : Shelterwood system (evolving towards High forest) or Coppice-with-standards system. Counts were made over a 9 year period of Passerinæ, Picidæ and Colum- bidæ breeding in the various stages of both successions. A transect method (Kilometric Index Abundance) was used, in conjunction with mapping plots, in 185 different sample areas chosen within a total forest area of 6000 ha. 1) Most breeding species are greatly influenced by vegetation physionomy, as effected by type of exploitation and age of the plot. Few species are capable of colonizing an area throughout the entire time span of a successional sequence. 2) Some species are favoured by a particular succession stage, whilst other species increase in numbers up to the sub-climax. Within each phyletic group, competition pressure is lessened by the different times at which species numbers are at their optimum level and by different tolerance limits to particular successional stages. 3) Many species show a preference for initial low scrub stages (Sylviidæ dominant) and still others for late sub-climax stages (Paridæ dominant). Very few species reach optimum abundance in intermediate high scrub stages (Turdidæ dominant). 4) The curve of total bird numbers follows a wave like form with two peaks of abundance. The first peak is attributable to the influx of exogenous, migratory forms which quickly enter recently cleared areas. The second peak corresponds to endogenous, sedentary forms, living in climax forest areas in the region. Intermediary successional stages, between cleared areas and climax forest, lack a distinct avi-fauna. 5) The number of breeding species parallels, with a high positive correlation, the total bird number. 6) Te mean size of breeding birds increases with the age of the succession. 7) The bird populations of the two successions differ greatly at the start of the successions, but increase in similarity with stand age. In the latter stages of the successions they are practically identical. The faunas at that time closely resemble that associated with the climax. 8) Vegetation heterogeneity is the major factor influencing bird abundance. Highest bird biomasses were recorded when the physionomy of the vegetation showed its greatest variability, thus attracting species belonging to the two groups mentioned above (point 4). 9) In the sub-climax stage, the mean individual size of birds and the proportion of sedentary forms are at their maximal values. On the other hand, neither abundance nor diversity are maximal in this stage

Manipulation and Optical Detection of Colloidal Functional Plasmonic Nanostructures in Microfluidic Systems

The very strong optical resonances of plasmonic nanostructures can be harnessed for sensitive detection of chemical and biomolecular analytes in small volumes. Here we describe an approach towards optical biosensing in microfluidic systems using plasmonic structures (functionalized gold nanoparticles) in colloidal suspension. The plasmonic nanoparticles provide the optical signal, in the form of resonant light scattering or absorption, and the microfluidic environment provides means for selectively manipulating the nanoparticles through fluid dynamics and electric fields. In the first part we discuss recent literature on functionalized colloidal particles and the methods for handling them in microfluidic systems. Then we experimentally address aspects of nanoparticle functionalization, detection through plasmonic resonant light scattering under dark-field illumination and the electrokinetic behavior of the particles under the action of an alternating electric field

A Methodology and Tool for Rapid Prototyping of Data Warehouses using Data Mining: Application to Birds Biodiversity

International audienceData Warehouses (DWs) are large repositories of data aimed at supporting the decision-making process by enabling flexible and interactive analyses via OLAP systems. Rapid prototyping of DWs is necessary when OLAP applications are complex. Some work about the integration of Data Mining and OLAP systems has been done to enhance OLAP operators with mined indicators, and/or to define the DW schema. However, to best of our knowledge, prototyping methods for DWs do not support this kind of integration. Then, in this paper we present a new prototyping methodology for DWs, extending [3], where DM methods are used to define the DW schema. We validate our approach on a real data set concerning bird biodiversity

Gravel pits support waterbird diversity in an urban landscape

We assessed the benefit of 11 gravel pits for the settlement of waterbird communities in an urbanized area lacking natural wetlands. Gravel pits captured 57% of the regional species pool of aquatic birds. We identified 39 species, among which five were regionally rare. We used the Self Organizing Map algorithm to calculate the probabilities of presence of species, and to bring out habitat conditions that predict assemblage patterns. The age of the pits did not correlate with assemblage composition and species richness. There was a positive influence of macrophyte cover on waterbird species richness. Larger pits did not support more species, but species richness increased with connectivity. As alternative wetland habitats, gravel pits are attractive to waterbirds, when they act as stepping stones that ensure connectivity between larger natural and/or artificial wetlands separated in space

Using mid infrared to perform investigations beyond the diffraction limits of microcristalline pathologies: advantages and limitation of Optical PhotoThermal IR spectroscopy

Understanding the physico-chemistry related to cristalline pathologies constitutes a challenge in several medical specialities such as nephrology, dermatology or oncology. Regarding nephrology, the chemical diversity of concretions such as kidney stones calls for characterization techniques to determine the chemical composition of concretions. The starting point of this contribution is given by Fourier Transform InfraRed (FTIR) spectroscopy which is routinely used at the hospital to determine the chemical composition of kidney stones as well as ectopic calcifications present in kidney biopsy. For kidney stones, the quantity of sample is sufficient to perform a significant analysis through classical FTIR. For ectopic calcifications, $\mu$FTIR can be inefficient in the case of $\mu$calcification in the tissue when their size is less than 10 $\mu$m. For such samples, Optical PhotoThermal IR (OPT-IR) spectroscopy may constitute a way to overcome this experimental difficulty through the acquisition of IR spectrum with a spatial resolution close to 500 nm.To illustrate such opportunity, we first compare the IR spectrum acquired with a classical experimental set-up related to classical IR spectroscopy to IR spectrum collected with a OPT-IR one for different compounds namely calcium oxalate monohydrate, calcium oxalate dehydrate, calcium phosphate apatite and magnesium ammonium phosphate hexahydrate. Such comparison helps us to assess specificity of OPT-IR. Then, we consider several pathological calcifications associated to hyperoxaluria, adenine phosphoribosyltransferase (APRT) deficiency or the presence of Randall’s plaque. We will see that the nanometer spatial resolution constitutes a major advantage versus a micrometre one. Also, in the case of Randall’s plaque, we show that OPT-IR can determine the chemical composition of microscopic concretion without any kind of preparation. Such experimental fact is clearly a major advantage. Finally, we also extended this first investigation in nephrology by considering breast calcifications. In that case, if the number of chemical phases is quite low compared to the number of chemical phases identified in ectopic calcifications present in kidney (four instead of 24), the challenge is related to the possibility to distinguish between the different calcium phosphate namely amorphous carbonated calcium phosphate, CA and whitlockite.The complete set of data indicates the limitations and the advantages of OPT-IR spectroscopy

Using mid infrared to perform investigations beyond the diffraction limits of microcristalline pathologies: advantages and limitation of Optical PhotoThermal IR spectroscopy

Understanding the physico-chemistry related to cristalline pathologies constitutes a challenge in several medical specialities such as nephrology, dermatology or oncology. Regarding nephrology, the chemical diversity of concretions such as kidney stones calls for characterization techniques to determine the chemical composition of concretions. The starting point of this contribution is given by Fourier Transform InfraRed (FTIR) spectroscopy which is routinely used at the hospital to determine the chemical composition of kidney stones as well as ectopic calcifications present in kidney biopsy. For kidney stones, the quantity of sample is sufficient to perform a significant analysis through classical FTIR. For ectopic calcifications, $\mu$FTIR can be inefficient in the case of $\mu$calcification in the tissue when their size is less than 10 $\mu$m. For such samples, Optical PhotoThermal IR (OPT-IR) spectroscopy may constitute a way to overcome this experimental difficulty through the acquisition of IR spectrum with a spatial resolution close to 500 nm.To illustrate such opportunity, we first compare the IR spectrum acquired with a classical experimental set-up related to classical IR spectroscopy to IR spectrum collected with a OPT-IR one for different compounds namely calcium oxalate monohydrate, calcium oxalate dehydrate, calcium phosphate apatite and magnesium ammonium phosphate hexahydrate. Such comparison helps us to assess specificity of OPT-IR. Then, we consider several pathological calcifications associated to hyperoxaluria, adenine phosphoribosyltransferase (APRT) deficiency or the presence of Randall’s plaque. We will see that the nanometer spatial resolution constitutes a major advantage versus a micrometre one. Also, in the case of Randall’s plaque, we show that OPT-IR can determine the chemical composition of microscopic concretion without any kind of preparation. Such experimental fact is clearly a major advantage. Finally, we also extended this first investigation in nephrology by considering breast calcifications. In that case, if the number of chemical phases is quite low compared to the number of chemical phases identified in ectopic calcifications present in kidney (four instead of 24), the challenge is related to the possibility to distinguish between the different calcium phosphate namely amorphous carbonated calcium phosphate, CA and whitlockite.The complete set of data indicates the limitations and the advantages of OPT-IR spectroscopy

L’avifaune nidificatrice d’une forêt de chênes pédonculés en Bourgogne : étude de deux successions écologiques

Ferry C., Frochot Bernard. L’avifaune nidificatrice d’une forêt de chênes pédonculés en Bourgogne : étude de deux successions écologiques . In: La Terre et La Vie, Revue d'Histoire naturelle, tome 24, n°2, 1970. pp. 153-250

Une méthode pour dénombrer les oiseaux nicheurs

En deux premières saisons (1956 et 1957) d’étude, où nous avons fait 66 dénombrements en 43 sorties, nous avons utilisé pour dénombrer les Oiseaux nicheurs com parativement dans les différents stades du taillis sous futaie, une méthode linéaire qui s’efforce de compter tous les couples nicheurs grâce à une sévère standardisa tion des conditions d’observation. Nous aboutissons à un Indice kilométrique d’ Abondance, qui représente, pour chaque espèce, le nombre de couples nicheurs dans un espace de 1 Km. de long et une largeur égale à la dis tance où l’espèce considérée se fait remarquer de l’obser vateur. Cet indice, qui est proportionnel à la densité, permet d’étudier l’influence des conditions écologiques sur cha que espèce étudiée. Pour apprécier les variations de l’avifaune globale, il faudra multiplier les I.K.A. par un facteur de conver sion, à calculer pour chaque espèce, qui donne la densité réelle