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[en] Coastline is an environmental place with assets as recreational and productive value. Monitoring of State is necessary for management of reactions to human action, extreme storms or climate change needs indicators as instruments for measuring evolution. Indicators need to be simple, easy to gauge and to make public, so as to be used in Agendas 21 or human development sustain ability.geologic couches associated to storm high energy and rocks visible s in beaches can be used as indicators. Playa Ramirez, near the center city, shows a high energy couch e mostly linked to a great storm in August 2005 and gneiss rocks from Montevideo formation more o less covered with sand responding to storms and currents transport balance. Both can be indicators integrating storms and currents effects useful for monitoring specific systems, which are to be identified in each part of the coast. (author)
[en] In this study, Soil and Water Assessment Tool (SWAT), a widely used semi distributed model (Arnold et al. 1998; Srinivasan et al. 2010; Saraf and Regulwar 2018) is adopted for estimating streamflow in Upper Godavari (UG) basin, a sub basin of Godavari river, India. The UG basin receives less rainfall compared to other sub basins of Godavari catchment, which is a major source of water for agricultural dominant land within the basin. Availability of large storage capacity in small groups of reservoirs in the catchment, improper measurements of runoff, gaps in runoff observations gives additional challenges to model the river system. Therefore, there is a strong need to determine exact potential of the watershed up to Jayakwadi dam located at the outlet of the UG basin. Secondly, streamflow estimations in large river catchments is becoming a serious issue in recent decades due to the obstruction of natural river flow by large storage structures constructed across the rivers. Improper estimation can lead to the false results which can further take hydrologic modellers near to the non-realistic results leading to failure of water resources management (Ikhar et al. 2018). Hence, the main objective of the present study is to estimate the streamflow in UG basin using SWAT model by considering several large reservoirs located within the catchment. Further, quantification of parameter uncertainty in hydrological modeling is necessary to obtain its sensitivity information. SWAT requires a large number of input parameters, which complicates model parameterization and calibration. SWAT-CUP provides a decision-making framework that incorporates a semi-automated approach (SUFI2, ParaSol) using both manual and automated calibration and incorporating sensitivity and uncertainty analysis especially with reservoir details.
[en] Ka and Ku bands links for shore-ship communications suffer limited bandwidth and high loss. In this paper, photonics-based links are proposed and modeled. The principle of phase modulation (PM) is elaborated and analyzed. It is showed that PM can effectively suppress high-order inter-modulation distortion (IMD), reduce the insert loss and improve the reliability of the system. (paper)
[en] Sandy beach can be divided into two beach ecosystems: self-sustaining and interface, which respond in different ways to morphodynamic and climate control on biodiversity. The main factors which act upon sandy shore biodiversity are wave energy and wind action, which are responsible for the movement of sediment and the determination of beach inclination. Climactic variations, such as storms, also significantly influence the dynamic of sandy shores. Although they have a delicate ecological balance, sandy shores have not been recognized as priority areas for conservation, possibly due to the absence of exuberant vegetation cover or due to the lack of perception of their biodiversity. For the majority of people that frequent coastal areas, sandy shores appear to be poor biological systems and are valued only for scenic and recreational purposes. Intense recreational use and the unorganized use of the backshore increases the impacts on these environments, altering sediment deposition which increases the difficulty of biota movement and increases erosion processes, compromising ecosystem functionality. It is therefore, necessary to research indicators which can result in the creation of effective strategies for coastal management, preserving ecosystem balance and the maintenance of its services, including those considered essential for the human race. This revision principally aims to discuss how morphodynamic and climactic processes act upon sandy beach biodiversity and how these phenomena can influence ecosystem balance and the offering of their services. We also discuss the possible interferences of climactic alterations, unorganized occupation of coastal environments and their implications for the conservation of sandy shores. (author)
[en] Highlights: • Erosion in the first years after nourishment is due to infiltration and profile formation. • Study of the shoreline evolution using aerial images since 1956 • The erosion rates are different in beaches with similar characteristics. • The greatest erosion occurs at beaches where sediment particles are more fractured. Coastal erosion is a worldwide problem, so accurate knowledge of the factors involved in the shoreline evolution is of great importance. This study analysed three gravel beaches that were nourished with sand from the same source. However, the evolution of their shoreline was different in each case. For its analysis, different factors were studied such as the shoreline and cross-shore profile evolution, the maritime climate, sedimentology and mineralogy. From the results, it should be noted that Centro beach is the most stable with a loss of surface after the first regeneration of 12.8%, while Carrer de mar is the most instable with a loss of 20.9%. The Posidonia oceanica meadow is one of the factors that make Centro beach the most stable despite being the one that receives the most wave energy. Another factor is its mineralogy and more specifically the composition of the particles that form the sample. Thus, it is observed how the cracking or the formation of particles by different minerals with a fragile union, are factors that make the beaches behave differently against erosion. For this reason, it is concluded that in order for the shoreline to be as stable as possible over time, a previous study of the sediment to be used for nourishment is necessary, as well as its possible effect on the ecosystem, since the future shoreline evolution will depend on it.
[en] The way in which sediment relocation and tilling (or aeration) treatment techniques accelerate the removal of oil from beaches was discussed. Examples of applications of the techniques on recent spills were reviewed. Both techniques basically accelerate the two natural cleaning processes of physical abrasion and oil fines interaction. The issue of where and when the techniques should be used or avoided was also discussed. The techniques can be applied to oiled sediments in or above the tidal zone. They can also be used on oil that has penetrated into subsurface sediments or has been buried. The problem is that these in situ techniques are underused, hence their application is limited because of the lack of experience or knowledge and understanding on the part of the decision makers. The rate of accelerated cleaning is a function of the amount and type of oil spilled and of the naturally occurring rates of abrasion and oil-fines interaction on the beach. 33 refs., 3 tabs., 2 figs
[en] Restinga formations grow on sandy spits of coastal plains, an environment whose conditions limit the growth and development of vegetal species. Studies on restinga gradients are good examples of how plants acclimate to restrictive environments. This work compares three woody species co-occurring in four vegetations of a restinga from Southern Brazil. It pinpoints morpho-anatomical attributes that favor the survival of species faced with spatial variability of soil and light conditions. Results indicate that they respond differently to environmental variables on different scales. The plastic response of morphological attributes is more marked than that of anatomical ones. Varronia curassavica and Dodonaea viscosa showed more xeromorphic features on the more stressful restinga formations while Symphyopappus casarettoi varied between xerophyte to mesophyte forms along the gradient. Individual height, fresh and dry leaf masses, leaf area, specific leaf mass and area, leaf density, and water content are particularly noteworthy. These responses are strategies allowing the studied species to survive in restinga environment with highly variable soil nutrient, water availability, and light conditions. The environmental conditions are important features that modulate de plant morphology along the gradient.
[en] Highlights: • Urban carbon sinks were assessed in the Pearl River Delta region. • Influence of spatial positions of city features on carbon sinks was detected. • The carbon sink per unit area increased with distance from the city centers. • Carbon sinks decreased with increases in road grades. • The locations of rivers also influenced the carbon sinks. Locations of city features, e.g., city centers, roads, railways, and rivers, may impact urban carbon sinks. Therefore, the effects of city features on spatial variations of urban carbon sinks were investigated using geographic proximity data. The main results were as follows. (1) Carbon sink function varied in a complex manner with distance from the city center and with city size. The carbon sink per unit area increased with distance from the prefecture-level city center (0–30 km), with the dominant influence occurring within a 9 km radius. The lowest carbon sink per unit area was observed at a distance of 12 km from the city center of the provincial capital city (Guangzhou) and special economic zone (Shenzhen), which may be suburban industrial zones. (2) Carbon sinks decreased with increases in road grades as a result of the different functions and traffic flow, and carbon sinks were lowest near city express ways. For highways, carbon sinks were lower near highway entrances and exits. Carbon sinks around ordinary railways were higher than those around subways and light rail, but carbon sink characteristics grew more complex with increasing distances from subways and light rail. (3) Rivers were closely related to the urban layout. Grade I (i.e., larger) rivers were associated with lower carbon sinks, and carbon sink characteristics became increasingly complex around larger rivers. Within a 0–1000 m distance of all rivers, the carbon sink per unit area increased rapidly, but carbon sink characteristics differed slightly for grade I rivers. This study implies that it is important to take urbanization spatial position effects into account while assessing regional carbon sinks during urbanization and development.
[en] This study is conducted on the usage of remote sensing images from several different years in order to analyze the changes of shoreline and land cover of the area. Remote sensing images used in this study are the data captured by the Landsat satellite. The images are projecting the land surface in 30 by 30 meter resolution and it is processed by the ENVI software. ENVI is able to change each digital number of the pixels on the images into specific value according to the applied model for classification in which could be used as an approach in calculating the area different classes based from the images itself. Therefore, using this method, the changes on the coastal area are possible to be determined. Analysis of the shoreline and land reclamation around the coastal area is integrated with the land use changes to determine its impact. The study shows that Batu Pahat area might have undergone land reclamation whereas in Pasir Gudang is experiencing substantial amount of erosion. Besides, the changes of land use in both areas were considered to be rapid and due to the results obtained from this study, the issues may be brought about for the local authority awareness action. (paper)