The effect of natural habitat and human activities on large cat’s predation risk in a tropical landscape: including spatial and temporal scales in a two-dimensional approach

The evaluation of aquifer recharge is essential to make a quantitative evaluation of renewable groundwater resources required to implement proper water policies aimed at maintaining stream–aquifer interactions, guaranteeing water supply to human activities, and preserving groundwater-dependent ecosystems at different spatial and temporal scales and climate conditions [...]

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Effects of hydropeaking on groundwater mixing: from laboratory experiments to field scale observations

10.5194/egusphere-egu21-1533 ◽

2021 ◽

Author(s):

Mónica Basilio Hazas ◽

Francesca Ziliotto ◽

Giorgia Marcolini ◽

Massimo Rolle ◽

Gabriele Chiogna

Keyword(s):

Groundwater Flow ◽

Transport Processes ◽

Mixing Enhancement ◽

Two Dimensional ◽

Field Scale ◽

Flow Topology ◽

Temporal Scales ◽

Spatial And Temporal Scales ◽

Flow And Transport ◽

River Stage

<p>Hydropeaking, an artificial flow regime consisting on strong and frequent river stage fluctuations, is known to have important effects on groundwater-surface water interaction. It influences the transient dynamics of water flow and also of solute and energy fluxes between aquifers and rivers. In this work, we focus on the effects of hydropeaking at multiple spatial and temporal scales. We start the investigation at the laboratory scale using quasi-two-dimensional flow-through experiments in which we can characterize &#160;flow and transport mechanisms, as well as the topology of the flow field, at high spatial and temporal resolution. We measure and model the spatial moments, the dilution index and the Okubo-Weiss parameter of a transient plume, and find a correlation between changes in flow topology and mixing enhancement. We then investigate a two-dimensional field scale cross section representative of the Adige aquifer in North-East Italy, where two rivers differently affected by hydropeaking influence groundwater flow, and we investigate the system considering hourly and mean daily fluctuations in the river stage. We characterize the transient groundwater dynamics for this and for other aquifers affected by hydropeaking using the Townley number, analyzing the potentiality of such systems for chaotic advection. Finally, at regional scale we use a three-dimensional transient model to show how the Adige aquifer is differently affected by hydropeaking depending on dry and wet years. Moreover, we apply the continuous wavelet transform to identify the main temporal scales of variability detected in the groundwater fluctuations and how they change with time. Our work therefore highlights the relevance of the effect of hydropeaking on groundwater flow and transport processes, and its impact on flow topology and mixing enhancement at multiple spatial and temporal scales.</p>

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Shifting perspectives: method, media and the complex image

History and Computing ◽

10.3366/hac.1998.10.1-3.100 ◽

1998 ◽

Vol 10 (1-3) ◽

pp. 100-108 ◽

Cited By ~ 1

Author(s):

Alicia Colson ◽

Ross Parry

Keyword(s):

Image Processing ◽

Three Dimensional ◽

Geographical Location ◽

Spatial Relationship ◽

Two Dimensional ◽

Dimensional Approach ◽

Complex Image ◽

Cultural Resonance

This article argues that the analysis of a threedimensional image demanded a three-dimensional approach. The authors realise that discussions of images and image processing inveterately conceptualise representation as being flat, static, and finite. The authors recognise the need for a fresh acuteness to three-dimensionality as a meaningful – although problematic – element of visual sources. Two dramatically different examples are used to expose the shortcomings of an ingrained two-dimensional approach and to facilitate a demonstration of how modern (digital) techniques could sanction new historical/anthropological perspectives on subjects that have become all too familiar. Each example could not be more different in their temporal and geographical location, their cultural resonance, and their historiography. However, in both these visual spectacles meaning is polysemic. It is dependent upon the viewer's spatial relationship to the artifice as well as the spirito-intellectual viewer within the community. The authors postulate that the multi- faceted and multi-layered arrangement of meaning in a complex image could be assessed by working beyond the limitations of the two-dimensional methodological paradigm and by using methods and media that accommodated this type of interconnectivity and representation.

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