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Mapping of flooded areas in the Nemunas river delta using remote sensing methods.
No full textFlooded areas in the Nemunas River delta are dynamic and ever-changing environments, depending on weather, hydrology, and other conditions, such as topography, soil, and land cover. Most common factors of flooded areas formation in the Nemunas River delta are human activities, such as the installation of embankments or polders. Areas that are flooded for a long time can affect vegetation communities and types. Flooded areas can cause significant changes in physical processes, such as water flow and water evaporation in a river basin. In extreme situations, emission of methane gas (CH4) can occur from flooded areas, which are more potent greenhouse gas than CO2. Due to these environmental traits, it is important to determine hotspots of flooded areas to assess the problem and find the solution for improvement of ecology in these type of areas, such as the installation of embankments and polders. In this study 3 drone flights were completed in two areas in the Nemunas River delta (near Kintai village and Sakūčiai forest) during the period between 2019-2021. Images taken from drones were mosaicked using photogrammetry and used for the validation of flooded areas retrieval results from Synthetic Aperture Radar (SAR) images and supervised classification training. Flooded areas in the Nemunas River delta in Lithuania and Russia were investigated using SAR Sentinel-1 during the period 2015-2019. SAR image preparation and classification was done using Google Earth Engine, which is a powerful web platform for cloud-based processing of remote sensing data on large scale. For flooded areas, the mapping was done using two different methods: Random Forest Classification and change detection. With the Random Forest Classification method, it was possible to detect land, open water, and temporally flooded vegetation, while with the change detection method only open water could be delineated from the land. Eventually, using change detection method, hotspots were compared with soil type, land cover, and topographical wetness index (TWI) data. Validation of method classification showed that the Random Forest Classification method (92,9 ± 2,2 %) yielded a better result than the change detection method (84,7 ± 11,2 %). Even though the Random Forest Classification method yielded better results, it is considered to be a much complicated method to use in practice, as for training this method requires the collection of classification points during the field, while the change detection method approach only requires meteorological and hydrological information for selecting the right dry period for comparison. Hotspots analysis showed that most often flooded areas were found on the right bank of the Nemunas River, which is part of the Lithuania. The most common flooded areas were spotted around the Sakūčiai forest, around the Žalgiriai forest, and around the Bundalai forest. The analysis of hotspots and TWI of most potential places of flooded areas showed only 7 % of correspondence. While the most important factors for flooding are high precipitation and river water level, this was not the case with flooded areas, as comparison between flooded areas and these factors have not showed correlation. Results showed that flooded areas can be affected by other factors, such as land cover, soil, and topography
The structure of benthic communities on the edge of the retreating glaciers in western Svalbard, Arctic.
No full textFor the last decades' temperatures in the Arctic, fjords increased dramatically. Due to the warming climate, glaciers in Svalbard are not forming fast enough during winter, which leads to a winter ice area loss trend close to 10 percent per decade since 1979 (Onarheim et al., 2014). Increased melting and retreat of glaciers on Svalbard leads to the release of coastal marine habitats in the upper sublittoral for colonization by benthic macroorganisms where ice scouring was a limiting factor (Węsławski et al. 2011). Benthic communities near retreating glaciers are also being affected by sediment stability, larger inorganic particle concentration, sedimentation rate, and amount of organic matter in sediments (Wlodarska-Kowalczuk, Pearson, 2004). The study of the benthic structure under these pressures is important for understanding the processes occurring in the Arctic. The majority of benthic studies in the Arctic, including Svalbard, were done in deeper depths (100-1000m), with the main focus on easily accessible large fjords and bays using large ships and traditional sampling techniques. However, complex bottom topography and the presence of floating ice significantly complicates the use of traditional sampling methods, forcing us to look for alternative approaches. One such technique is underwater visual technology, which has grown in popularity in recent decades based on its effectiveness in hard-to-reach places. In this work, it will be demonstrated that the use of an underwater video mosaic based on video filming along transects in the upper sublittoral can be a reliable method for identifying communities of visible macro-fauna. This work aimed to assess the structure of benthic communities on the West coast of Svalbard in melting ice and ice-free zones and to determine the regularities of the structure of these communities or functional groups in terms of the melting glacier and geographical location. Underwater video filming was carried out in July-August 2018-2019 in the upper sublittoral (2 –65 m) of Hornsund and Isfjord areas (western Svalbard), representing two ice-free (Gipsvika, Adriabukta) and two glaciated sites (Borebukta, Burgerbukta). Almost 3 hours of video materials were obtained using an ROV and "drop-down" video cameras. Video footage was transformed into 148 video mosaics, from which 33 biological features (morphospecies) were identified to the lowest possible taxonomic level, which were further ascribed to benthic functional groups (feeding type and mobility mode), and those were used for further analysis of benthic communities. The study showed that benthic communities in Borebukta which is located near retreating glaciers are largely dominated by mobile fauna (79,8 %) and scavengers (78,5 %), while communities in ice-free sites - Gipsvika (98,8 %), Adriabukta (64,2 %), and in one of the retreating glacier sites - Burgerbukta (90,4 %) are dominated by discretely mobile individuals. Suspension feeders were dominating in Gipsvika (63,5 %), Adriabukta (98,1 %) and Burgerbukta (91,0 %). In the West Svalbard study area 8 morphospecies was dominating: tube-dwelling anemone Ceriantharia, bivalves, feather duster worms Sabellidae, brittle stars, bioturbating polychaetes, shrimps, bryozoa Alcyonidium sp. and unidentified Bryozoa undet. individuals. In Burgerbukta (54 ± 84 ind. trans-1), Adriabukta (49 ± 68 ind. trans-1), and Gipsvika (25 ± 34 ind. trans-1) bays feather duster worms Sabellidae were the most dominant one, forming up to 50 % of total relative individual abundance, in Borebukta bay Ophiurida (76 ± 169 ind. trans-1) comprised 78,4 % of total relative individual abundance. Morphospecies richness, Shannon-Wiener diversity, and Pielou evenness indices did not show any significant differences between ice-free and glaciated sites. Nevertheless, the Hulbert index showed significant differences between Adriabukta (5,33 ± 1,52) and Gipsvika (1,6 ± 0,89) sites. MDS and ANOSIM analysis showed that benthic communities were statistically different in all bays (Global ANOSIM R: 0,758; p = 0,001) also that bays geographical allocation determined larger similarities between bays (Global ANOSIM R: 0,398; p = 0,001) than presence of melting ice (Global ANOSIM R: 0,501; p = 0,001). Finally, 4 benthic communities were distinguished. Sabellidea community which was most dominant in retreating glacier site Burgerbukta, and in Gipsvika which is affected by riverine discharge; bioturbating polychaetes (a most likely feature of sandworm Arenicola marina) which was most dominant in shallow riverine bay transects of Gipsvika; brittle stars community dominated in Borebukta and Bryozoans together with bivalves that were dominant in ice-free site Adriabukta. After these results, it is evident that melting ice is impacting the distribution of the sublittoral macrozoobenthic community structure in the study area
Evaluation of the energy consumption of container diesel trucks in a container terminal: a case study at Klaipeda port /
No full textIntroduction: In the paper, we examine the energy consumption efficiency of specialized container diesel trucks engaged in container transportation at a seaport terminal. Objectives: Using the container terminal at Klaip_eda in Lithuania as the background for the research, we produced an improved energy consumption model for measuring the theoretical energy consumption and regeneration of diesel trucks at the terminal and provide a comparative analysis. Methods: We created a mathematical model which describes the instantaneous energy consumption of the diesel trucks, taking into account their dynamic properties and the overall geometry of their routes—‘‘Ship-Truck-Stack-Ship’’—using the superposition principle. We investigated other critical parameters relevant to the model and provide a statistical evaluation of the transportation process using data from a case study of Klaip _eda port, where we collected measurements of container transportation parameters using georeferenced movement detection and logs from wireless equipment positioned on the diesel-powered container trucks. Results: The modeling results showed that an instantaneous evaluation of energy consumption can reveal areas in the container transportation process which have the highest energy loss and require the introduction of new management and process control initiatives to address the regulations which are designed to decrease harmful industrial emissions and encourage novel technologies and thereby increase the eco-friendliness of existing systems
Potential analysis of low economic value fish in Lamongan Regency, East Java, Indonesia /
No full textThe purpose of this study was to determine the potential of low commercial value fish species in Lamongan Regency, East Java, Indonesia. The processed data included primary and secondary data. Data were processed using the LQ method and analyzed descriptively by way of compiling data into tables. The survey results showed that there are ten types of low commercial value fish in Lamongan Regency, East Java, Indonesia, namely Sardinella fimbriata (Tembang fish), Leiognathus bindus (Peperek fish), Harpadon nehereus (Puso fish), Sardinella lemuru, (Lemuru fish), Saurida tumbil (Beloso fish), Gerres abbreviatus (Kapasan fish), Anodontostoma chacunda (Juwi fish), and Cynoglossus lingua (Lidah fish). The results of the LQ method showe that there are three types of fish that have the potential to be made of high economic value products, namely L. bindus (11.36), A. chacunda (2.35), and S. fimbriata (2.32). Fish Auction (TPI) that has the potential in terms of fish productivity to be developed is TPI Weru, Lamongan, East Java, Indonesia. The typology of fishermen in TPI Weru has less experience working as a fisherman than other TPI but the level of education is higher and the age of fishermen is younger so that it affects the productivity of fish catches
Phytoplankton of the Curonian Lagoon as a new interesting source for bioactive natural products. Special impact on cyanobacterial metabolites /
No full textThe bioprospecting of marine and brackish water systems has increased during the last decades. In this respect, microalgae, including cyanobacteria, and their metabolites are one of the most widely explored resources. Most of the bioactive compounds are isolated from ex situ cultures of microorganisms; however, analysis of field samples could also supply valuable information about the metabolic and biotechnological potential of microalgae communities. In this work, the activity of phytoplankton samples from the Curonian Lagoon was studied. The samples were active against antibiotic resistant clinical and environmental bacterial strains as well as against serine proteases and T47D human breast adenocarcinoma cells. No significant effect was found on Daphnia magna. In addition, using LC-MS/MS, we documented the diversity of metabolites present in field samples. A list of 117 detected cyanopeptides was presented. Cyanopeptolins constituted the largest class of cyanopeptides. As complex bloom samples were analyzed, no link between the observed activity and a specific sample component can be established. However, the results of the study showed a biotechnological potential of natural products from the Curonian Lagoon
Investigation of ground anchors in the reconstruction project quay No. 137A and consideration of alternatives by using GEO5 software.
No full textIn Chapter I of this Master's Thesis (hereinafter referred to as BD) the retrospective of ground anchors, currently the most commonly used types of anchors, installation technology, exploitation and monitoring are analyzed. The main design provisions, requirements and recommendations are examined. The application possibilities of Geo5 software and the variety of its subroutines for solving various geotechnical tasks are also described in this work. In this section the investigation of the Reconstruction Project of Klaipeda port quay No. 137A (hereinafter referred to as the Project) is presented. The designed conditions and tasks of the Project are presented in Chapter II. While using GEO5 software the solution of the Project was modeled, as well as 17 different alternatives with three different anchor tilt angles (26,5°; 35,0°; 45,0°), three different anchor lengths (27,5 m; 30,5 m; 33,5 m) and two different anchor root lengths (12,5 m; 15,0 m). This chapter examines the solution envisaged in the Project and its alternatives, presents the calculation schemes of the models and the calculation results. In Chapter III the calculation results are compared and graphs are presented. Possible alternatives are identified and described, also the results of their calculation are presented. The possible alternatives of the Project solution examined in BD are presented in the Conclusions and Recommendations chapter and the possible factors that influenced such calculation results are discussed. Suggestions for improving GEO5 software are provided. Valancius L. Investigation of Ground Anchors in the Reconstruction Project Quay No. 137A and Consideration of Alternatives by Using GEO5 Software. Port structures study programs final master’s thesis. Supervisor prof. dr. J. Rutė, Klaipeda University: Klaipeda, 2021. 75 p. and Annexes 9