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Debris flow events, generated by surface runoff, occur with great frequency in the Dolomites (Northeastern Italian Alps) during the summer season. Summer thunderstorms, which are common in the region, can quickly generate runoff at the base of rocky cliffs, which then entrains and propagates downstream the underlying unconsolidated material. In the past, the main atmospheric feature considered in evaluating the initiation of debris flow events was rainfall. Observations led to the development of rainfall intensity–duration thresholds for sediment mobilization, which compared incoming severe rainfalls with the potential for triggering debris flows. This study works toward the examination of another characteristic of the atmosphere, the atmospheric electric field. In particular, the behavior of the electric field prior to convective rainfall is investigated as an indicator of rainfall intensities capable of triggering debris flows, in a basin near Cortina d’Ampezzo (Italy). Results suggest that prior to bursts of intense rainfall, the electric field derivative frequency distribution exhibits a recurrent pattern roughly half the time. When it occurs, the amplitude of derivative frequency distribution intersects the zero axis twice before rainfall reaches maximum intensity. A regression model is designed which considers the amplitude maximum and the difference in time between the crossings of the zero axis. The validation of this model suggests a mild relationship between electric field and rainfall intensity in an alpine environment.

Les espaces souterrains suscitent des angoisses et des peurs qui sont liées à un imaginaire largement défavorable. Notre contribution vise à esquisser les grands points cardinaux de l’imaginaire de la profondeur souterraine en s’appuyant sur l’anthropologie française de l’imaginaire (Gaston Bachelard, Gilbert Durand). Celle-ci établit que l’imaginaire nourrit une relation émotionnelle et affective à l’espace, qui est structurante de l’expérience d’un monde. Les qualités de l’espace souterrain prennent dans l’imaginaire un caractère ambivalent. À partir d’une bibliographie littéraire des grands récits qui condensent les différentes composantes de l’ima­ginaire du souterrain en des ensembles d’images cohérents, nous établissons cinq points cardinaux de l’imaginaire du souterrain qui en forment les topiques. La première, la profondeur, est la plus prégnante et a donné lieu à de nombreux récits, notamment ceux consacrés aux enfers, dont l’imaginaire reste omniprésent aujourd’hui. Les autres qualités sont la clôture de l’espace, l’absence de repères, l’espace en creux, et l’espace dessous par rapport à un dessus. L’imaginaire du souterrain largement marqué par l’angoisse laisse aussi place au repos le plus profond, à la quête initiatique et l’envie de se dépasser, au plaisir de l’exploration et à la subversion créatrice. Cette ambivalence qui fait la richesse de notre expérience nous permet de nourrir des pistes pour l’aménagement des espaces souterrains urbains actuels. Celles-ci visent à ce que les espaces souterrains puissent être intégrés dans l’expérience d’un monde. Underground spaces raise anxieties and fears that are linked to a highly unfavorable imagination. Our contribution aims to establish the major cardinals points of the imaginary of the deep-underground based on the French anthropology of the imaginaire (Gaston Bachelard, Gilbert Durand). It states that the imagination nurtures a human emotional and affective relationship with space which structures the experience of a world. In the imagination, the qualities of underground spaces take on an ambivalent character. From a literary bibliography of the great stories that condense the various components of the imaginary underground into coherent sets of images, we identify five topical cardinal points of the imaginary of the underground. Firstly, depth is the most pregnant and has given rise to many stories, especially those devoted to the underworld, whose imagination still remains widespread today. Other features are the closure of space; the absence of landmarks; hollow space and the space below with respect to the space above. The imaginaire of the underground largely marked by anxiety also leaves room for other themes such as deep rest, the initiation quest, the desire to excel, fun exploration and creative subversion. The ambivalence of these qualities contributes to the richness of our experience and allows us to nurture leads towards the development of existing urban underground spaces combined in diverse strategies. The aim is to integrate underground spaces into the experience of a world.

Microbial contaminations in the culture plates are quite common in microbiological laboratory. The preparation of culture plates is an art thereby the scientific principles should be adhered strictly. While preparing the culture plates, chance of contamination is high either due to inadequate sterilization or improper handling. In general, the prepared plates should not use or store at low temperature immediately. The sterility checking is very important before impregnation the plates for microbiological procedures. This study is aimed to analyze the discarding criteria of the contaminated plates either partly or completely. Two sets of nutrient agar plates were prepared and kept for sterility checking overnight at room temperature. The type of contaminants were assessed; thereby colonies on the surface or underneath the surface. Both the sets were kept for another day for the development of contamination in the contaminant free plates recorded on the day 1. The results revealed that two types of contaminants were found in two sets. Set one have the colonies on the surface and no further contamination found on day 2 in the non-contaminated plates indicated that the contamination may occur during plating procedures. Set two have the colonies underneath the surface and contamination developed on day 2 in the non-contaminated plates due to improper sterilization of the glassware and culture media. Thus from this study, it was recommended that the set one plates which are not contaminated are used for further processing, whereas the entire set two should be discarded. The major significance of this work is to understand the importance of sterility checking before using the nutrient plates for culturing.

Armillaria root disease is found in many temperate and tropical forests throughout the world. It is responsible for on average 2-4% of mortalities in infected forests. This root disease is caused by many species of fungus from the Armillaria genus. They are commonly referred to as Honey Fungus. This fungus spreads mainly through the interaction of tree roots. The Wind River Forest Dynamics Plot shows evidence of an infection by Armillaria. However the extent of the infection has not been studied or mapped. Research Question : How much of the WFDP is infected and what are the effects of Armillaria on the plots mortality?

Theoretical models predict nurse plant facilitation enhances species richness by ameliorating stressful environmental conditions and expanding distributional ranges of stress-intolerant species into harsh environments. We studied the role of nurse facilitation on the recruitment of perennial plants along an arid scrubland–temperate rain forest boundary to test the following predictions: (1) nurse shrub canopy increases seedling abundance and species richness along the rain forest–scrubland boundary; (2) scrubland species are less dependent on facilitative interactions than temperate rain forest species, especially at the moister, upper end of the gradient.