Natural landscape | EPFL Graph Search

A natural landscape is the original landscape that exists before it is acted upon by human culture. The natural landscape and the cultural landscape are separate parts of the landscape. However, in the 21st century, landscapes that are totally untouched by human activity no longer exist, so that reference is sometimes now made to degrees of naturalness within a landscape. In Silent Spring (1962) Rachel Carson describes a roadside verge as it used to look: "Along the roads, laurel, viburnum and alder, great ferns and wildflowers delighted the traveler’s eye through much of the year" and then how it looks now following the use of herbicides: "The roadsides, once so attractive, were now lined with browned and withered vegetation as though swept by fire". Even though the landscape before it is sprayed is biologically degraded, and may well contains alien species, the concept of what might constitute a natural landscape can still be deduced from the context. The phrase "natural landscape

Inception of Regular Valley Spacing in Fluvial Landscapes: A Linear Stability Analysis

Shashank Kumar Anand

Incipient valley formation in mountainous landscapes is often associated with their presence at a regular spacing under diverse hydroclimatic forcings. Here we provide a formal linear stability theory for a landscape evolution model (LEM) representing the action of tectonic uplift, diffusive soil creep, and detachment-limited fluvial erosion. For configurations dominated by only one horizontal length scale, a single dimensionless quantity characterizes the overall system dynamics based on model parameters and boundary conditions. The stability analysis is conducted for smooth and symmetric hillslopes along a long mountain ridge to study the impact of the erosion law form on regular first-order valley formation. The results provide the critical condition when smooth landscapes become unstable and give rise to a characteristic length scale for incipient valleys, which is related to the scaling exponents that couple fluvial erosion to the specific drainage area and the local slope. The valley spacing at first instability is uniquely related to the ratio of the scaling exponents and expands logarithmically with an increase in this ratio. We find compelling evidence of sediment transport by diffusive creep and fluvial erosion coupled with the specific drainage area equation as a sufficient mechanism for first-order valley formation. We finally show that the predictions of the linear stability analysis conform with the results of numerical simulations for different degrees of nonlinearity in the erosion law and agree well with topographic data from a natural landscape.

2022

Perception and use of landscape concepts in the procedure of Environmental Impact Assessment: Case study-Switzerland and Romania

Alexandre Buttler, Andreea Nita

The European Landscape Convention (ELC) defines landscape as "an area, as perceived by people, whose character is the result of the action and interaction of natural and/or human factors". Because all aspects linked to landscape are evaluated during the Environmental Impact Assessments (EIAs) procedure, we assessed the Swiss and Romanian experts' perception and EIA reports regarding the landscape concept. Therefore, we analysed Swiss and Romanian experts' perception of landscape, we evaluated concepts and methods used in environmental impact reports to assess landscape characteristics and functions, and how the ELC's aim and objectives are reflected by the EIA reports. The Canonical Correspondence Analysis performed to evaluate the experts' perception of landscape integration in the EIA procedure showed a significant relationship among pattern of answers and experts' professional background. Moreover, there is a significant difference between Swiss and Romanian expert's perception. Longer experience in the field and a higher level of education indicates higher awareness of landscape characteristics and properties, which demonstrates that alongside with the initial training, there is a need for developing a coherent long-life learning systems having landscape analysis as a focus. The ELC is familiar to nearly 86% of the Romanian Environmental Impact Assessment actors and nearly 29% of the Swiss experts. By contrast, most of the Romanian EIA reports analysed do not employ many concepts of the ELC, while most of the Swiss environmental reports incorporate objectives of landscape protection consistent with the Convention. Our study relies on the comparative investigation of representative case studies of Environmental Impact Assessment reports for industry, local infrastructures, tourism facilities, and wind farm projects, as well on tracking how the European Landscape Convention is reflected by the EIA reports. We found that EIA reports from both countries evaluate the visual landscape, thus, achieving subjective assessment of landscape aesthetics without focusing on social and ecological sub-systems. Quantitative elements of landscape analysis are mostly absent and it is challenging to evaluate whether environmental assessments are consistent among European Landscape Convention countries. To overcome the abstract way of evaluation of project's impact on landscape through EIA procedure, an improved landscape analysis procedure is needed and we propose developing technical guidelines, under the European Landscape Convention umbrella, in order to enhance landscape management. (C) 2014 Elsevier Ltd. All rights reserved.

Elsevier Sci Ltd2015

Perception and use of landscape concepts in the procedure of Environmental Impact Assessment: Case study-Switzerland and Romania

Alexandre Buttler, Andreea Nita

Elsevier Sci Ltd2015