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Rees Catalan A.K.,CNRS Environment City Society
Environmental Development | Year: 2015

The Monarch Butterfly Biosphere Reserve is located in central Mexico at the state border of Michoacán and Mexico, is the primary wintering area for the monarch butterfly (Danaus plexippus) and an important water aquifer for Toluca and Mexico City valley. Since the reserve's expansion in 2000, several efforts have been made to integrate nature preservation and social development. Therefore, the main objective of this paper is to analyse the territorial dynamics generated by the participation mechanisms that have been implemented in this region. Mexican environmental law only allows the National Commission of Protected Areas to make final decisions, thus, true participative management, defined as effective citizen power, including in the decision-making processes between citizens and institutions, is not legally recognized in the country. However, some mechanisms exist to enhance participation. The Monarch Fund, which pays for environmental services, has helped to improve acceptance of the protected area, even though opportunity costs are not fully covered. In the process of establishing leadership, NGOs play a central role as valid intermediaries between institutional and local resident stakeholders, working for increased social participation. However, strengthening social participation is limited by the characteristics of Mexican social organizations, ejidos and comunidades, in which three social classes exist with different rights pertaining to each category. Nevertheless, micro-regional councils and the consultative council make a long-term relationship between stakeholders possible; every inhabitant, regardless of social status, can take part in the process. These elements led us to state that participation is not exemplary but is quite promising. © 2015 Elsevier B.V. Source

Canadian national parks are well-known for protecting natural areas dedicated to 'the benefit and the enjoyment of the Canadian people'. The history of national parks illustrates the evolution of a concept of nature from functional conservation, such as tourism, to an environmental conception, based on ecosystem protection and biodiversity preservation. Banff, Waterton Lakes and Wood Buffalo National Parks in Alberta, and Kootenay National Park in British Columbia (four of the fourteen parks established before 1930, the year the National Parks Act was passed) have been chosen for this study in order to understand how national parks have dealt with local communities since the beginning of the national park movement, and how these relationships have changed during the last forty years. Inclusion of local communities and collaborative management processes have been well developed in northern Canadian parks since the mid-eighties. These practices have been considered successful in this region, but the situation is very different in the southern parks, especially those that were created before 1930. However, things have changed since Aboriginal culture and rights have been recognized in judgements rendered by the Supreme Court of Canada and by the Canadian Constitution. In the four parks chosen for this study, involvement of local communities and the development of their participation have been slow. Round tables and participation in the creation of interpretation sites and exhibits of Aboriginal history can be considered a step toward further cooperation. ©/ Canadian Association of Geographers / L'Association canadienne des géographes. Source

Renard F.,CNRS Environment City Society
Theoretical and Applied Climatology | Year: 2016

The Greater Lyon area is strongly built up, grouping 58 communes and a population of 1.3 million in approximately 500 km2. The flood risk is high as the territory is crossed by two large watercourses and by streams with torrential flow. Floods may also occur in case of runoff after heavy rain or because of a rise in the groundwater level. The whole territory can therefore be affected, and it is necessary to possess in-depth knowledge of the depths, causes and consequences of rainfall to achieve better management of precipitation in urban areas and to reduce flood risk. This study is thus focused on the effects of topography and land cover on the occurrence, intensity and area of intense rainfall cells. They are identified by local radar meteorology (C-band) combined with a processing algorithm running in a geographic information system (GIS) which identified 109,979 weighted mean centres of them in a sample composed of the five most intense rainfall events from 2001 to 2005. First, analysis of spatial distribution at an overall scale is performed, completed by study at a more detailed scale. The results show that the distribution of high-intensity rainfall cells is spread in cluster form. Subsequently, comparison of intense rainfall cells with the topography shows that cell density is closely linked with land slope but that, above all, urbanised zones feature nearly twice as many rainfall cells as farm land or forest, with more intense intensity. © 2016 Springer-Verlag Wien Source

Notebaert B.,Catholic University of Leuven | Notebaert B.,Research Foundation Flanders | Piegay H.,CNRS Environment City Society
Geomorphology | Year: 2013

In this study the floodplain width (FW) was assessed for the entire RhÔne catchment river network (32,160. km long) to highlight controlling factors. The FW data, which is measured every kilometre on a digital elevation model (DTM), is aggregated into spatial homogenous segments using a Pettitt break detection test, resulting in aggregated geographical objects (AGO). Based on these AGOs, an analysis of the variability of the floodplain width was performed. The general pattern for the RhÔne network shows a downstream increase in FW related to the concept of river continuum. This general pattern explains ca. 30% of the variation in FW. Deviations from this general trend are, however, large. Values for floodplain widths are normalized for catchment scale to study deviations that do not depend on scale effects. Based on a conceptual model, the main environmental parameters influencing FW were identified. These parameters include lithology and different parameters that influence the river profile, such as base level changes and tectonics, sediment load and discharge. An analysis of catchment-wide patterns shows that the main variations on the scaling effect are caused by lithology. Superposed on this general scaling pattern, disturbed by lithological variations, are the variations in floodplain width caused by disturbances in the geomorphic system, which influence floodplain slope, sediment, and water discharge and which include inherited landscapes. Although large data sets become increasingly available and the applied methodology reduces data noise, data availability and quality still hampers studies at a larger scale. Nevertheless, such information sources are becoming crucial because they are more and more accessible and diverse, and the analysis is now easier with the increasing capacities of GIS technologies. As a result, they are becoming very complementary to field studies to understand geomorphic processes at wider spatial and longer temporal scales. In a sense, the tradition of geomorphology may evolve in the next years, with image data providing additional evidence of Earth evolution. © 2013 Elsevier B.V. Source

Salvador P.-G.,Lille University of Science and Technology | Berger J.-F.,CNRS Environment City Society
Geomorphology | Year: 2014

This paper concerns the evolution during the Holocene of the floodplain of the Rhone River in the Basses Terres basin, 70. km northeast of Lyon. Geomorphological mapping of a number of paleochannels has been carried out, using topographic maps, aerial photos, and landform surveys, and mechanical cores have been taken that enable the reconstruction of several stratigraphies in cross section. The chronology of fluvial deposits relies mainly on the radiocarbon dating of organic materials collected from the abandoned fluvial fills. Paleochannel infillings were also used to record fluvial style changes and floodplain aggradation rates. The main results show that the region has a mountainous piedmont plain controlled by local factors (inherited from glacial times) that have led to the atypical predominance of a meandering river pattern controlling the evolution of the floodplain in the Basses Terres area during the Holocene. A major avulsion of the Rhone, when it switched to its present-day northern course around 2700-2600. cal. BP, strongly influenced the evolution of the Holocene floodplain, causing a sharp decrease in the aggradation of the abandoned section. In addition, four major occurrences of strong and increased sediment discharge took place around 10,000-7500, 3000-2700, 2400/1500-1000, and 230-50. cal. BP. Two of these (ca. 3000-2700 and 230-50. cal. BP) are correlated to a braided pattern and represent temporary fluvial metamorphoses of the Rhone. The infilling rates of several paleochannels also reveal periods of strong sediment deposition around 5500-5250, 3500-3200, 1400-1200, and 600-400. cal. BP, consistent with previous regional paleohydrological phases as well as new ones. These phases are synchronous with the hydrosedimentary variations identified on a regional scale in the Rhone catchment area and the northern Alps. © 2013 Elsevier B.V. Source

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