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Use of Spectral Indices to Identify the Changes in the Vegetation Community Over Time After Restoring a Palustrine Wetland: a Case Study of Spencer Island Regional Park, Everett, WA

Abstract

Wetland restoration can be measured over time using community vegetation as an effectiveness indicator of restoration actions. Spencer Island Regional Park is part of the tidal freshwater wetlands along the Snohomish river basin. Those wetlands are part of a complex ecosystems, in which they are included as a salmon corridor. This research analyzes the vegetation community changes over time after restored in 1996 on Spencer Island Regional Park, Everett, Washington State, U.S. I analyzed three spectral indices using segmentation and supervised classification of land cover from 1997 to 2018. I found that in the last 21 years, the areas with emergent palustrine vegetation and forests increased, in contrast to diminishing areas of upland and scrub-shrub classes. Those finds can be interpreted that the community vegetation advanced to higher wetland successional stages as upland areas have been colonized by emergent wetland plant communities. A linear regression model predicted that by 2025, the difference between emergent and upland classes should increase. Empirical evidence is presented that support the integration of spectral indices to identify changes in community vegetation. However, it is recommended for future studies to include spectral indices and spatial information for soil and hydrology to deepen these results.

Open access
Hydraulic Characterization of a Self-Weight Compacted Coal

Abstract

Water infiltration through coal stocks exposed to weather elements represents a key issue for many old mining sites and coal-fired power plants from the environmental point of view, considering the negative impact on human health of the deriving groundwater, soil and air pollution. Within this context, the paper investigates the hydraulic behaviour of a self-weight compacted unsaturated coal mass and its impact on the numerical prediction of infiltration induced by rainfall events. In particular, the work focuses on the experimental investigation carried out at different representative scales, from the grain scale to physical modelling. The material, when starting from uncompacted conditions, seems to be characterized by metastable structure, which tends to collapse under imbibition. In addition, direct numerical predictions of the seepage regime through a partially saturated coal mass have been performed. As the compaction of the coal stock induced by dozers has not been taken into account, the numerical simulations represent a conservative approach for the assessment of chemical pollution hazard associated to water infiltration into a real stockpile under operational conditions.

Open access
Topographic surface modelling using raster grid datasets by GMT: example of the Kuril–Kamchatka Trench, Pacific Ocean

Abstract

The study area is focused on the Kuril–Kamchatka Trench, North Pacific Ocean. This region is geologically complex, notable for the lithosphere activity, tectonic plates subduction and active volcanism. The submarine geomorphology is complicated through terraces, slopes, seamounts and erosional processes. Understanding geomorphic features of such a region requires precise modelling and effective visualization of the high-resolution data sets. Therefore, current research presents a Generic Mapping Tools (GMT) based algorithm proposing a solution for effective data processing and precise mapping: iterative module-based scripting for the automated digitizing and modelling. Methodology consists of the following steps: topographic mapping of the raster grids, marine gravity and geoid; semi-automatic digitizing of the orthogonal cross-section profiles; modelling geomorphic trends of the gradient slopes; computing raster surfaces from the xyz data sets by modules nearneighbor and XYZ2grd. Several types of the cartographic projections were used: oblique Mercator, Mercator cylindrical, conic equal-area Albers, conic equidistant. The cross-section geomorphic profiles in a perpendicular direction across the two selected segments of the trench were automatically digitized. Developed algorithm of the semi-automated digitizing of the profiles enabled to visualize gradients of the slope steepness of the trench. The data were then modelled to show gradient variations in its two segments. The results of the comparative geomorphic analysis of northern and southern transects revealed variations in different parts of the trench. Presented research provided more quantitative insights into the structure and settings of the submarine landforms of the hadal trench that still remains a question for the marine geology. The research demonstrated the effectiveness of the GMT: a variety of modules, approaches and tools that can be used to produce high-quality mapping and graphics. The GMT listings are provided for repeatability.

Open access
Lamprophyric rock locations in Greece

Abstract

Twenty-four areas with lamprophyric formations have been located through a bibliographic search in Macedonia, Thrace, the islands and Attica. Most lamprophyre types have been identified including rare “alkali minette”. In most localities the dikes/sills appear to be late mantle products associated with deep faulting following extensional activity in granitoids.

Open access
The assessment of the suburbanisation degree of Warsaw Functional Area using changes of the land development structure

Abstract

The paper presents the analysis of spatial suburbanization using a multi-indicator method. Based on features related to geodetic areas (according to the directions of their use) such as built-up areas, urbanised lands, arable lands, residential, recreation and leisure areas, road transport areas as well agricultural and forest areas transformed into local land development plans - six suburbanization indicators were developed. After the standardisation of such indicators, a summary index was obtained making it possible to determine the suburbanization degree. The validation of the proposed method was made by comparing individual municipalities with the unit type determined using the Webb method. The analysis made it clear that the only four units with spatial features of the city lying in the proximity of Warsaw, for which Polish capital could be enlarged are: Piastów, Pruszków, Marki, Józefów and possibly Sulejówek.

Open access
Borders on the old maps of Jizera Mountain

Abstract

Old maps, mainly from the period between 1890 and 1940, have been collected in the framework of the project “Old Maps of the Jizera Mountains”. These maps provide us with a complex picture, mainly of tourism, in this currently Czech–Polish territory.

The territory of the Jizera Mountains was inhabited mainly by a German-speaking population on both sides of the border until 1945. Yet it is interesting to examine how the border between the two states – in those times Czechoslovakia and Germany, now Czechia and Poland – was illustrated on these old maps. This article argues that the border was not perceived as a barrier as such until later on, mainly due to the ethnic change in the borderlands. It also reveals that the borders on the maps are of manifold nature and cannot be simply limited to the national borders.

Open access
Disappointment or unexpected gain? A survey-based study of the motives and outcomes of inter-municipal cooperation in Poland

Abstract

Based on a survey of inter-municipal unions (IMUs) and inter-municipal companies (IMComs) in Poland, this article identifies the most common motives for launching inter-municipal cooperation and the most frequently reported outcomes. The declared motives are compared with the perceived outcomes, with a particular focus on mismatch situations: disappointments (when the expected gain was not realised) and unexpected outcomes (when the reported outcomes exceeded initial expectations). The research shows that the latter are reported more frequently than the former. The most frequently indicated motives for cooperation were related to financial benefits and included cost reduction and applying for additional funding. The “defensive” motive of IMC – cooperation to maintain the status quo – is practically absent. The data also suggests that cooperation can be perceived as “a value in its own right”.

Open access
Evaluating map specifications for automated generalization of settlements and road networks in small-scale maps

Abstract

The presented research concerns the methodology for selecting settlements and road networks from 1:250 000 to 1:500 000 and 1:1 000 000 scales. The developed methodology is based on the provisions of the Regulation of the Ministry of Interior from 17 November 2011. The correctness of the generalization principles contained in the Regulation has not yet been verified. Thus this paper aims to fulfil this gap by evaluating map specifications concerning settlement and road network generalizations.

The goal was to automate the selection process by using formalized cartographic knowledge. The selection operators and their parameters were developed and implemented in the form of a generalization model. The input data was the General Geographic Object Database (GGOD), whose detail level corresponds to 1:250 000 scale. The presented research is in line with works on the automation of GGOD generalization performed by the National Mapping Agency (NMA) in Poland (GUGiK). The paper makes the following contributions. First, the selection methodology contained in the Regulation was formalised and presented in the form of a knowledge base. Second, the models for the generalization process were developed. The developed methodology was evaluated by generalizing the settlements and roads in the test area. The results of the settlement and road network generalization for both 1:500 000 and 1:1 000 000 detail levels were compared with the maps designed manually by experienced cartographers.

Open access
Mapping India since 1767: transformation from colonial to postcolonial image

Abstract

Indian civilization has over 2500 years of mapping tradition. With the establishment of the Survey of India in 1767, British rulers initiated the mapping of colonial India with high precision and accuracy. They started mapping to establish British power and supremacy in the Indian subcontinent that portrayed a British image of India. Following independence in 1947, the Survey of India and other national agencies started mapping India for planning and development. Hence, questions have been raised that, how far British image of India have been transformed into an Indian image. In this context, in this paper an attempt has been made to analyse the mapping of India from the perspectives of transforming a colonial into a postcolonial image. The transformation occurred mainly in terms of purpose i.e. maps as a tool for the expansion of territory to planning, development and governance, from analogue to digital in method and in strategy from restricted to liberal access.

Open access
Modelling Of Rock Joints Interface Under Cyclic Loading

Abstract

The problem of numerical simulation of the material interface response under monotonic and cyclic loading is of fundamental scientific and engineering importance. In fact, such interfaces occur in most engineering and geotechnical structures. The present work is devoted to the deformational response analysis of contact interfaces under monotonic and cyclic loads. The class of materials includes rock and structural joints, soil structure interfaces, masonry and cementitious joints, localized shear bands and so on.

The aim of the proposed model is to simulate the cyclic shear test under constant normal load. The associated dilatancy effect is associated with the configurational effects of asperity interaction or dilatancy of wear debris layer. The large primary asperities are assumed as responsible for interfacial dilation and small size asperities as governing frictional sliding and hysteresis response. The elliptic loading yield function is assumed to translate and rotate during progressive or reverse loading events. The model formulation is discussed and confronted with experimental data.

Open access