Sand Dune Area Research Articles

Two centuries of forest succession, and 30 years of vegetation changes in permanent plots in an inland sand dune area, The Netherlands

Two centuries of forest succession, and 30 years of vegetation changes in permanent plots in an inland sand dune area, The Netherlands

Pollen analysis of animal coprolites recovered from vegetation mounds in El-Ga’ab paleolake: evidence for vegetation history of the desert of northern Sudan

In arid zones vegetation mounds are natural indicators for land degradation. Studying plants and animals remains in different strata of these mounds provide information about the past land use in which parts of the natural environment were modified into arable fields and pastures. They are suitable sites for preserving animal coprolites. In this study, two samples of different animal coprolites were collected from vertical trenches in vegetation mounds of Um Hilal and El-Hamra areas of El-Ga’ab depression in northern Sudan. Pollen grain analysis was conducted and eleven species that belong to eight families were identified. Five species recorded for El Hamra area and nine species were identified for Um Hilal area. Most of the pollen grains were identified as Suaeda monoica and Salsola imbricata which are halophytes indicates habitats of high soil salinity in El-Ga’ab depression. These species are still dominant in other law elevated areas of less dry sand dunes. Polygonum sp. Pollens were recorded in Um Hilal area indicating a moist habitat. Record of the comparatively large number of tree pollen grain of Acacia ehrenbergiana indicates no change in the dominant tree species. Presence of the pollen grains of Triticum sp. (wheat) and Heliotropium parciflorum is an evidence for past agricultural activities. This study recommended further intensive investigations of the old dry vegetation mounds distributed in the desert of northern Sudan to reconstruct its palaeoenvironment.

Stakeholder analysis for controlling land utilization in Parangtritis sand dunes

Land use change in coastal sand dune is a problematic issue that can arise due to inappropriate use. Stakeholders have a large role in the management of sand dune. This study aims to identify and map the role of stakeholders in relation to land utilization in Parangtritis sand dunes. Land use distribution was analyzed using ArcGIS software, while the method used for stakeholder analysis was in-depth interviews. The stakeholders in this study are the Spatial Planning Agency of Bantul Regency (DPTR), the Environmental Agency of Bantul Regency (DLH), Parangtritis Geomaritime Science Park (PGSP), Tourism Awareness Group (Pokdarwis), Save Our Sand Dune Lives (SOSDL), village government, and the local community. The result indicated that many anthropogenic activities were identified on the sand dune area, which in turn can endanger the existence of this landform. Based on the results of the analysis, it shows that the stakeholders included in the role of the main players (key players) are DPTR, DLH, PGSP, Pokdarwis, and SOSDL. Meanwhile, stakeholders included in the subject category are the village government and the local community. There is no communication forum for management, supervision, and control of the sand dune conservation area, as well as integration between stakeholders.

Reconstruction of German Coastal Defense Line in 1942-1944 and Search for Military Historical Heritage Objects. Bolshoi Tyuters Island. Data of Geophysical Methods and Excavations.

The article describes the results of full-scale geophysical 2017-2018 studies conducted with the purpose of detecting military historical heritage objects on Bolshoy Tyuters Island. Sand dunes located in the eastern part of the island were studied in a short time by detailed magnetic exploration with an observation step of about 1 m. The most interesting anomalies of the magnetic field were investigated with the georadiolocation method. The processed results provided for mapping the anomalous magnetic field and creating georadiolocation sections and a dimensional relief model which demonstrate anomalies related to German defense and are promising for further excavations. The pinpoint excavations of the identified anomalies made it possible to explain their nature and discover objects of historical value at depths of up to 5 m. Despite high "contamination" of the dunes with metal debris, the use of geophysical methods with a dense observation system made it possible to detect a large number of objects of military historical heritage and significantly reduce the volume of excavations. Linking of the German positions archival scheme at hand additionally provided for comparing the location of the objects found with symbols made on it. After systematization and generalization of all the information obtained during 4 years of research on the island, it is possible to reconstruct the system of German defense in the area of sand dunes with a high degree of reliability.

Characterizing the cultural ecosystem services of coastal sand dunes

Coastal sand dunes provide an array of important benefits that are supported by coastal geomorphic processes and location-specific ecosystems, including direct and indirect economic benefits to humans. Coastal sand dune ecosystems are ecologically important, but their specific values and uses are little studied, poorly understood, and underappreciated. Michigan, USA, is home to the largest land area of freshwater coastal sand dunes in the world. This study used an online survey that allowed participants to record the types of activities in which they engaged during visits and respond to questions about the importance of the cultural ecosystem services of coastal sand dunes. The survey captured the responses of 3610 individuals, a majority of whom rated scenic beauty, protection for future generations, protection of a unique ecosystem, and outdoor recreation as extremely important or very important. The survey results provide some preliminary insights into the role of cultural ecosystem services of coastal sand dunes in providing and sustaining benefits for humans and how these benefits and values are perceived by the public. These insights have important implications for policy makers responsible for coastal zone management in the Great Lakes region and in other areas characterized by coastal sand dunes ecosystems.

Introducing an intelligent algorithm for extraction of sand dunes from Landsat satellite imagery in terrestrial and coastal environments

In this study, an intelligent algorithm for the extraction of sand dune maps from Landsat satellite images in terrestrial and coastal environments was presented by a case study of the sand dunes in northeastern Iran and one example on the coast of the Oman Sea in southeastern Iran. First, to find the best sand dune detection algorithm, the land cover map is created by aerial photography and field observation in ILWIS software. Next, a binary image is created in which the sand dunes are considered as white pixels and other parts as black pixels. In the next step, the pixels of each land cover map class are divided into 50 equal parts, one part of them is used to train different smart grids and the rest of them are used for evaluation. Then the classification is done using all 50 parts in turn, and the Correct Classification Rate (CCR) index is calculated. This action is performed for the K-Nearest Neighbor, Decision Tree, AdaBoost, RUSBoost, and SVM algorithms. Furthermore, to see the effect of the PCA and LDA statistical methods, the classifier algorithms are implemented by applying these techniques. Finally, the proposed method was tested in a coastal area as an example. The findings show that the CCR of the proposed method is around 84% using 2% of the ground truth of the area for training and the other 98% of them for testing. In the case study, the detection results show that around 9.98% of the area is covered by sand dunes. To have a practical detection of the sand dunes area, the proposed machine learning method is applied to some experimentally verified points. Based on the results, ensemble classification methods, especially RUSBoost, have the best detection accuracy. Also, the result of its test on the coastal sand dunes showed its ability to identify, map, and monitor the sand dunes in coastal areas.

Evolution of groundwater recharge as a result of forest development on the east coast of the province of Buenos Aires, Argentina

Changes in groundwater recharge associated with variations in land use were analysed with a focus on the role of afforestation on the east coast of Buenos Aires, Argentina. The growth of the population related to such changes was considered, linking water consumption to variations in recharge. A multi-temporal analysis was carried out using aerial photographs for the years 1957, 1975, 1981 and 2016, differentiating three types of cover: bare soil, forested soil and grassland. Water balances for each type of land use and groundwater recharge were estimated. In the forested soil, a reduction in recharge over time can be observed and it can be appreciated that forest expansion occurs at the expense of the sand-dune area, which offers the greatest possibilities for infiltration. At present, the water consumption, which depends solely on the groundwater reserves, is lower than the recharge, but this relationship is reversed during the tourist season. According to the estimated projections, the drinking water supply would be compromised in the coming decades, reaching a critical point or level of collapse as from 2070. This proves that it is essential for the policies and projects aiming at afforestation for different purposes to take into consideration the role of this change in land use when assessing the sustainability of the associated water resources.

North Platte River-South Platte River Confluence Area Drainage System History as Determined by Topographic Map Interpretation: Western Nebraska, USA

Detailed topographic maps of the western Nebraska North Platte River-South Platte River confluence area show a low relief and gently sloping southeast-oriented upland surface, asymmetrical drainage divides, nearly adjacent and parallel east-oriented North and South Platte River valley segments, barbed tributaries, and shallow divide crossings (low points along drainage divides) in a region south of the Nebraska Sand Hills and at the Nebraska loess region’s western margin. Published interpretations of North and South Platte River confluence area landforms (referred to as the accepted paradigm) do not explain most drainage features and are compared with a new paradigm’s interpretations to determine which of the two paradigms explains the regional drainage history and related surface features in a simple and consistent manner. New paradigm interpretations require large sheets of slowly-moving southeast-oriented water to have flowed toward what was probably an actively eroding Republican River valley and to have shaped the upland surface while the Platte and North and South Platte River valleys eroded headward into and across the region so as to create the asymmetric drainage divides, barbed tributaries, and shallow divide crossings. These new paradigm interpretations are consistent with each other and with recently published new paradigm interpretations of upstream North and South Platte River drainage system history. New paradigm interpretations also suggest the adjacent Nebraska Sand Hills developed on a large flood deposited delta (typical of sand dune areas on former glacial lake deltas further to the north) and the slowly-moving sheets of water may have been responsible for some or all of Nebraska’s loess deposits, although the new paradigm leads to a fundamentally different middle and late Cenozoic regional geologic and glacial history than what workers using the accepted paradigm have described.

Wave-equation dispersion spectrum inversion for near-surface characterization using fibre-optics acquisition

SUMMARY Distributed acoustic sensing (DAS) acquisition is becoming more and more popular for its dense sampling at a lower cost than seismometers. However, data processing for DAS data is challenging, especially for surface-deployedfibers, in which only the horizontal component of strain variation is effectively recorded. Also, the coupling between the fiber and the Earth is usually poor and the recorded single-component data are noisy. Thus, we introduce data processing strategies dedicated to enhancing the ambient-noise and active-source seismic data recorded by a horizontally deployed tactical fiber-optics cable buried in a sand dune area in Saudi Arabia. We propose a similarity-weighted stacking of randomly selected short-time duration windows to generate virtual common shot gathers (CSG) from the recorded ambient noise. The similarity-weighted stacking only counts the primary contributions of coherent events, while a short-time correlation can suppress the crosstalk usually present in late arrivals. The stacking fold is preserved or even can be increased by generating plenty of random time segments compared to stacking the full recording time. For the recorded active-source data, we skip the interferometric step, but use the envelope of the CSG. The envelope is needed to mitigate the complexity of waveforms, while preserving the slopes of arrivals. Then, we use the wave-equation-based Rayleigh-wave dispersion spectrum inversion, which utilizes all the dispersion modes available and does not require picking the dispersion curve, in estimating the shallow S-wave velocities. The local cross-correlation objective function allows for additional freedom in matching the modelled and observed data, and thus, helps us avoid falling into a local minimum when starting with kinematically poor velocity models.

Assessment of Biological Spectrum and Phenological Behaviours of Coastal Vegetation in East Midnapore District, Eastern India

The open coastlines of the world are dominated by sand dunes and salt marshes. They are the primary areas for human recreation and provide a wide range of frequently overlooked ecosystem services. Their intrinsic ecological significance lies in having unique biological assemblies and supporting a range of ecological processes, such as water filtration and nutrient cycling. In addition, in the coastal zone, these areas link marine and terrestrial systems. The objective of this paper is to check the psammophytic species diversity, conservation status and threat; and also prepare a biological spectrum m in the Costal East Midnapore (CEM) district's sand dune and salt marsh areas. A part of floristic inventories in the CEM, various field trips in different season were carried out, quadrate method is done to examine the ecological impact and richness. Specimens were collected, prepared voucher specimen and enlisted according APG IV classification system to prepare biological spectrum. CEM vegetation was diverse and composed of 162 species of 132 genera distributed among 52 families of 28 orders according to APG IV classification, of which 37 species were exotics. Fabales (19.14%) and Fabaceae (19.14%) were the dominant order and family. Biological spectrum shows the study area was classified as “thero-chamaephytic” type of phytoclimate. Mesophyll (24.07%) and lanceolate as well as oblong (19.14%) were found to be high in the leaf size spectrum and lamina. The area of study was highly ecotonal potential and fairly undisturbed. This study is useful in comparing and contrasting the adjacent natural vegetation along the gradients of the environment; and recommends effective long-term conservation and better management of the coastal area.

Geoarcheomorphosites under Strong Urbanization Pressure at the Tineh Plain, NE of the Nile Delta, Egypt

Most geologic and geomorphologic features emerged on a deltaic plain resulted from the interplay of marine, land and river, of which are some have the potential to be a geoheritage site, this is called a geomorphosite. Over time, human impact due to settlements on the geomorphosite, reshaped and transformed the site to geoarcheomorphosite. The Great Pelusium, or Tell El-Farama, which is located along the Tineh Plain at the NE extreme of the Nile Delta between the third and fifth c. AD, is classified as a geoarcheomorphosite. The location includes several geomorphosites, such as the accreted coastal ridges, which record Late Holocene sea level changes. It also includes traces of the flash flood on the Pelusiac branch during the eighth c. AD, with the fluvial flood plain, natural levee, and crevasse splays, on which the Great Pelusium, Tell El-Luli, Tell El-Fadah, and Tell El-Makhzan were constructed. Recently, the area subjected to a hub development project, which may represent anthropogenic hazards that threaten the Great Pelusium. This study aims to quantify the potential anthropogenic hazards. The change detection shows that in 1984 the area of the geoarcheomorphosites was 424.8 km2, representing approximately 67.1% of the Tineh Plain, in addition to the sand dune area of 75 km2, representing 11.8%. In 2018, the area saw agricultural activities, fish farms, and an urban expansion that covered approximately 244.2 km2, representing 38% of the Tineh Plain. The construction of a new hub in the Suez Canal corridor and the addition of a new community of one million people in an area of 164 km2, representing 30.3% of the plain, will add more pressure on the geodiversity. A conservation plan is recommended in the form of sustainable development to save an important area of geoheritage in Egypt and convert the area into a tourism destination.

Long-term spatial distribution of vegetation and sand movement following the commencement of landscape conservation activities to curb grassland encroachment at the Tottori Sand Dunes natural monument

ABSTRACTSan’in Kaigan Geopark is recognized as a United Nations Educational Scientific and Cultural Organization (UNESCO) Global Geopark, and the Tottori Sand Dunes in the park are designated as a Natural Monument of Japan. In 1900, the area that constitutes the Tottori Sand Dunes was part of a vast coastal sand dune system. However, the encroachment of grasslands (grasslandisation) became a significant threat to the area and by 1991 about 42% of the surfaces of the sand dunes were covered with vegetation. This prompted the initiation of landscape conservation activities, primarily weeding, in 1994. We analysed the spatial distribution of sand movement based on aerial land survey data captured intermittently since 1964, and propose a method for evaluation of the vegetation cover ratio per 30 × 30-m cell (pixel polygons; PPs), based on unmanned aerial vehicle (UAV) photographs and satellite data. Our analysis showed that the inland slope of the second row of sand dunes has shifted landward by around 30 m due to extremely high deposition rates. The third row of sand dunes has also moved inland. Thus, the Oigo-suribachi Basin has gradually been buried along the coast due to significant sand sedimentation along the inland slope of the third row of sand dunes. We analysed the spatial distribution of the vegetation cover ratio on 9 May 1990, when the area of the encroaching grasslands was largest. A vegetated area with a vegetation cover ratio exceeding 0.40 extended from the first row of sand dunes to the west of the windbreaks located in the sand dune area. In the area in close proximity to the first row of sand dunes, the vegetation cover ratio was 0.51 in 1990 and reached 0.56 in 1995. However, it decreased rapidly to 0.14 by 1996, and since 2000 it has fluctuated within the range of 0.01–0.13.

Characteristics of Aeolian Dune, Wind Regime and Sand Transport in Hobq Desert, China

A systematic study of the wind regime characteristics in a region can not only accurately grasp the dynamic factors of the development of aeolian geomorphology, but also provide a scientific basis for the prevention and treatment of regional sand disasters. Taking the Hobq Desert as the study area, the basic characteristics of dune are analyzed by using remote sensing images. Based on the annual meteorological data of six meteorological stations from 2009 to 2018, the spatial and temporal distribution characteristics of wind speed were obtained. With the daily wind data of three stations from 2009 to 2018, we have figured out the wind regime and sand transport characteristics of the Hobq Desert. The results show that the sand dune height of the Hobq Desert ranges large, the highest height is 5010 m and the lowest is 10 m. It decreases gradually from the west to the east. The height of dune mainly distributed below 1500 m, followed by 1500–2000 m. Migratory sand dunes in Hobq Desert accounts for 51.8% and is mainly distributed in the west of the desert. The distribution area of fixation sand dunes in Hobq Desert is the least, accounting for 8.3%. The migratory dune pattern is trellis dune, semimigrated dune and semifixed dune patterns include honeycomb dune, parabolic duneand brush dune, and fixation dune pattern is grass dune. Annual wind speed was greatest in the southeast and decreased moving to the northwest. The dominant wind direction was W and SW from 2009 to 2018 in the Hobq Desert, the average wind speed of the prevailing winds mainly distributed at 4–8 m/s. The frequency of wind speed exceeding 10 m/s is very low, with a maximum value of 10% or below. There is a low energy wind environment in the Hobq Desert, with intermediate annual directional variability and obtuse or acute bimodal wind regime. The resultant drift direction (RDD)at Dongsheng station was relatively constant from 2009 to 2018, it was about 350°. RDD differed significantly at Baotou and Linhestations were 181 ± 169° and 231 ± 121°, respectively.The relationship between drift potential (DP) and the average and maximum wind speed was expressed as a power function. DP was strongly correlated with them. There is no significant correlated between the temporal changes in DPandprecipitation and temperature from 2009 to 2018 in the Hobq Desert.

Influence of submarine topography and associated sedimentary processes on the distribution of live and dead rhodoliths near Udo Island, Korea

The distribution of rhodoliths growing near the Udo islands in the Republic of Korea was identified and the controlling factors influencing their growth and distribution were investigated. Their mineralogical and textural features of growth patterns and the physical oceanographic properties that influence the rhodolith distribution were also examined. The study area is relatively shallow with a water depth of less than 20 m and thus is influenced by seasonal typhoons and winter storms as well as wind-driven waves and strong tidal currents. The study site was divided into four areas based on the distribution of the rhodoliths and the associated physical and biological factors. The bedrock-exposed area partially covered with live rhodoliths (area I) at depths of up to 10 m provides an environment characterized by high wave energy and irregular seabed topography, which precludes continuous rhodolith growth and accumulation. Living rhodoliths were rarely observed and the sediments continuously migrate to adjacent beaches and shallow waters. The depth range of 10–15 m can be divided into the northern (the active growth area of live rhodoliths, area II) and southern (the sand dune area with dead rhodoliths, area III) areas. The southern part, where underwater sand dunes appear, is predominantly distributed with sandy sediments and ripple marks, which makes it an adverse environment for continuous growth of rhodoliths. In contrast, the northern part has a bowl-shaped seabed with gentle slopes, providing a stable condition for the constant and active growth of rhodoliths. In areas deeper than 15 m (the seagrass-covered area with live rhodoliths, area IV), an irregular seabed topography is present and the wave energy is reduced. Consequently, various sizes of rhodoliths with bumpy surfaces are distributed throughout this area. Therefore, it is suggested that the distribution of the rhodoliths is affected by the bottom topography and the associated physical energy, in conjunction with different types of surface sediments. The results of this study will increase the understanding of rhodoliths elsewhere in the world.

Morphological species and discordant mtDNA: A genomic analysis of Phrynocephalus lizard lineages on the Qinghai-Tibetan Plateau

Many species have been established on the basis of morphology, with markers such as mtDNA used to confirm the existence of independent historical lineages. Discordance between morphology and gene trees makes this less straightforward. Genotyping by sequencing (GBS) was used to analyse general genomic divergence across two recognized high altitude lizard species found in the eastern Qinghai-Tibetan Plateau. One of the species (Phyrnocephalus guinanensis) is found on a large area of sand dune habitat and distinguished from the other (P. putjatia) by morphology. We found that the primary pattern of genomic divergence is discordant with these morphological species: northern P. putjatia populations from around the large saline Qinghai lake are genomically distinct from P. putjatia and P. guinanensis populations located south of the Qinghai South and Riyue Mountains. Two competing historical scenarios were assessed using approximate Bayesian computation which unequivocally favoured a split between populations separated by the Qinghai South and Riyue mountains over a split between morphological species. The findings indicate that historical vicariance due to geographical features underpins the phylogenetic split rather than ecology-mediated divergence between sand dune and non-sand areas which i) is predicted by the mtDNA tree (showing the utility of this marker in species delimitation) and ii) demonstrates the unsuitability of the morphology-based taxonomy (indicating that large morphological differences do not always reflect historical lineages). In addition, we found a clear signal of isolation-by-distance around the periphery of Qinghai lake which suggests: i) a high level of resolution by GBS for detecting local divergence and ii) restricted gene flow over relatively short geographic distances. Overall, we show how morphological variation can mislead taxonomic conclusions and the utility of GBS for resolving these issues.

Quantification of Recharge and Runoff from Rainfall Using New GIS Tool: Example of the Gaza Strip Aquifer

The Gaza Strip forms a transition zone between the semi-humid coastal zone in the north, the semi-arid zone in the east, and the Sinai desert in the south. Groundwater is the only water source for 1.94 million inhabitants, where the only fresh replenishment water for the aquifer comes from rainfall. This study focuses on testing a newly developed GIS tool to estimate the spatial and temporal distribution of runoff and recharge from rainfall. The estimation of surface runoff was made using the Soil Conservation Services Curve Number Method, while groundwater recharge was estimated using Thornthwaite and Mather’s Soil Moisture Balance approach. The new tool was applied to the Gaza aquifer for the year 1935 and for the period from 1973 to 2016. A comparison was made between the results obtained with the developed GIS tool and the frequently used Thiessen polygon method for rainfall distribution. Runoff and recharge were estimated for the year 1935 (prior to development) to compare with the current developed conditions. It was found that the built-up and sand dune areas stand in an inverse relationship, where the former is replacing the latter (built-up area expanded from 30.1 km2 in 1982 to 92.1 km2 in 2010). Recharge takes place in the sand dune area, whereas runoff increases in the built-up area. Due to development, runoff almost tripled from 9 million m3 in 1982 to 22.9 million m3 in 2010, while groundwater recharge was reduced from 27.3 million m3 in 1982 to 23 million m3 in 2010, even though the rainfall increased between 1982 and 2010 by 11%. Comparison between the newly developed GIS tool and the Thiessen polygon-based estimation shows that the former leads to higher values of runoff and recharge for dry years.

Evolution of runoff and groundwater recharge in the Gaza Strip over the last four decades

Gaza Strip is experiencing a severe water crisis caused mainly by overexploitation of the groundwater source. Rainfall is the only source of freshwater replenishment for the Gaza coastal aquifer. Groundwater level has dropped to more than 10 m below mean sea level as a result of aquifer exploitation and imbalance between recharge and abstraction in the past decades, which exposes the groundwater to seawater intrusion. As the only fresh water source recharging the aquifer is from rainfall, it is essential to estimate the annual recharge volume from rainfall. This paper is focusing on recharge estimation based on historical daily rainfall data for the past 41 years (1973–2014). An estimation of surface runoff was made using soil conservation services curve number method. An estimation of groundwater recharge has been calculated using two different methods: Thornthwaite and Mather soil moisture balance approach and chloride mass balance. Four land use maps and data have been used for the entire calculation period, three of them based on actual surveys carried out in 1994, 2004 and 2010, while the fourth map was developed based on the population expansion trend to cover the period before 1993. It was found that the proportion of built-up area has expanded from 8.25% in 1982 to 25.23% in 2010, while the sand dune area has shrunk from 31.46% in 1982 to 8.64% in 2010. Runoff has doubled from 6.9 million m3 in 1982 to 13.7 million m3 in 2010, while groundwater recharge was reduced from 24.4 million m3 in 1982 to 18.1 million m3 in 2010.

The Impact of Urbanization Expansion on the Geomorphology of the Southern Coastal Sabkhas from Ras Al-Jailiaha to Al-Khiran, South Kuwait

Kuwait is considered one of the desert regions of the Arabian Peninsula, that subjected to geomorphological processes forming the earth’s surface features. The anthropogenic activities through urbanization affected the earth geomorphology in the southern coastal sabkhas of Kuwait such as (Al-Jailiaha, Az-Zor and Al-Khiran). This study aims to monitor the geomorphological changes on the southern coastal sabkhas due to the urbanization expansion. Geographic information systems (GIS) and remote sensing (RS) techniques were used to study these changes, determine the areas of the coastal sabkhas in the southern part of Kuwait, following the developments, and identifying land cover in the area and its coastal strip including tourist resorts, sand dunes, and smooth sand sheets. The satellite images used in this study based on the data of Landsat-5 (TM) 1985, and Landsat-5 (TM) 1990, Landsat-7 (ETM+) 2001, visuals Landsat-8 (OLI) 2016 covering the years of (1985, 1990, 2001, 2016), in order to detect changes in the sabkhas and the extension of urbanization in the region. Digital Maps were made to show how extent the study area was affected by urbanization. Urbanization mostly expanded to the south in the study area on the account of the coastal sabkhas, where the area of the coastal sabkhas in 1985 was about 103.1 km2 and in 1990 it was about 84.1 km2. This led to the shrinking of the sabkhas area and extension of the resort area within the areas of sabkhas and sand dunes, particularly in Al-Khiran coastal area exposing it to the problem of sand drift and sand encroachment, which resulted in changes of the characteristics of the sabkhas, shrinkage of their area, and adverse impacts on their geomorphology.

Recommendation of Knockdown Building Design at Yogyakarta Sand Dunes (Restricted and Heritage Areas)

Sand dunes located in Special Region of Yogyakarta Indonesia is a restricted caused by the heritage and there only four spread in hemisphere one of them in Yogyakara, Indonesia. To build in sand dunes area building could not be built arbitrarily. Portable and knockdown is the character of the building that could be adjust to the conditions in Sand dunes. By the observation results compact building design with cold formed steel material for the main building material is the recommendation of this case. The design is then consulted with sub-contractors who are expert in their expertise as the validation stage, it is feasible to be transformed into a real building for the specific needs. Output of this research is recommendation of portable building model in modular form, where the design recommendation has been adjusted with building requirement in heritage and restricted area, which is also an area prone to tsunamis and wind disasters, therefore the recommended building are; easy to remove, easy to disassemble (knockdown), forward tsunami load, efficient cost and time (using cold formed steel material and prefabricated GRC), eco friendly (zero waste), does not require many workers (less man power).

Sand transport characterization on the foredune area of Parangtritis, Indonesia

The aim of the research are to determine the characteristics of sand deflation on Parangtritis foredune area. The development of tourism activity on surrounding area could be has a big impact to the sand transport process. Data required in this research are wind direction and its speed, the sand mass collected from sand sampler, sand grain size, roundness and sphericity, and interview from tourists. Sand that transported by wind collected by sand sampler with dimension of 0.76 cm height and 1 cm width. Sand transport rate or deflation calculated by Bagnold’s formula. The results showed that the deflation process is bigger at daytime observation that at night, it is average 2.42 g.m-1s-1during day and 0.03 g.m-1s-1during night. Each samples location have different deflation characteristics of material that transported. Grain diameters ranging from 0.318 mm to 0.395 mm with dominance texture is medium sand. Sphericity and roundness of sediment material was on a scale of 0.5 and 0.7. This natural process that occurred on the research area didn’t knowing well either by local communities or tourists. Therefore need some proper management for support the continuity of deflation process for supplying material to the main sand dune area of Parangtritis.