A multi-scale method to assess pesticide contamination risks in agricultural watersheds

The protection of water is now a major priority for environmental managers, especially around drinkingpumping stations. In view of the new challenges facing water agencies, we developed a method designedto support their public policy decision-making, at a variety of different spatial scales. In this paper, wepresent this new spatial method, using remote sensing and a GIS, designed to determine the contami-nation risk due to agricultural inputs, such as pesticides. The originality of this method lies in the useof a very detailed spatial object, the RSO (Reference Spatial Object), which can be aggregated to manyworking and managing scales. This has been achieved thanks to the pixel size of the remote sensing, witha grid resolution of 30 m × 30 m in our application.The method – called PHYTOPIXAL – is based on a combination of indicators relating to the environmen-tal vulnerability of the surface water environment (slope, soil type and distance to the stream) and theagricultural pressure (land use and practices of the farmers). The combination of these indicators for eachpixel provides the contamination risk. The scoring of variables was implemented according knowledgein literature and of experts.This method is used to target specific agricultural input transfer risks. The risk values are first calculatedfor each pixel. After this initial calculation, the data are then aggregated for decision makers, accordingto the most suitable levels of organisation. These data are based on an average value for the watershedareas.In this paper we detail an application of the method to an area in the hills of Southwest France. Weshow the pesticide contamination risk by in areas with different sized watersheds, ranging from 2 km2to 7000 km2, in which stream water is collected for consumption by humans and animals. The resultswere recently used by the regional water agency to determine the protection zoning for a large pumpingstation. Measures were then proposed to farmers with a view to improving their practices.The method can be extrapolated to different other areas to preserve or restore the surface water

Human Simulation and Sustainability : Ontological, Epistemological, and Ethical Reflections

publishedVersio

Human Simulation and Sustainability: Ontological, Epistemological, and Ethical Reflections

publishedVersio

【研究分野別】シーズ集 [英語版]

[英語版

Saliency Map for Visual Perception

Human and other primates move their eyes to select visual information from the scene, psycho-visual experiments (Constantinidis, 2005) suggest that attention is directed to visually salient locations in the image. This allows human beings to bring the fovea onto the relevant parts of the image, to interpret complex scenes in real time. In visual perception, an important result was the discovery of a limited set of visual properties (called pre attentive), detected in the first 200-300 milliseconds of observation of a scene, by the low-level visual system. In last decades many progresses have been made into research of visual perception by analyzing both bottom up (stimulus driven) and top down (task dependent) processes involved in human attention. Visual Saliency deals with identifying fixation points that a human viewer would focus on the first seconds of the observation of a scene

Insular Interconnectivity in the Viking Age: A Geospatial View from Norse Jarlshof

During the Viking Age, settlements and trading centers were often located near lakes, seas, waterways, and sailing routes. As such, access to other locations was facilitated, whether for the purpose of settlement, trade, resource acquisition, or conflict, by some form of seafaring vessel or watercraft. Over the course of the Scandinavian Diaspora, a level of cultural and economic interconnectedness was maintained between mainland Scandinavia and the settlements in the North Atlantic region. This shared link with Scandinavia contributed to the development of local connections between insular and coastal sites within the broader diasporic network. This thesis considers the archaeological evidence for insular interconnectivity during the Viking Age ca. 790-1066 CE in the British Isles and North Atlantic, as well as the potential for using a GIS-based joint visibility and mobility model that depicts the experiential use of, and interaction between, past landscapes and seascapes while maintaining a quantitative approach. This is considered through the evaluation of intervisibility between a mobile sailing ship entering the mouth of Grutness Voe and the occupants of the Norse farmstead at the Jarlshof archaeological site, Mainland, Shetland over the course of its occupation ca.850-1200 CE. The results of this research support the argument that the investigation of the diasporic maritime communities of the Viking Age can benefit from the use geospatial technology to evaluate insular interconnectivity and to better conceptualize broader patterns within those extensive maritime networks. Broadly speaking, these findings can also inform our understanding of coastal and insular populations in the past, and the way that they have engaged with their environment, both aqueous and terrestrial. Advisor: Heather Richards-Rissett