Hydrogeomorphological Units Research Articles

Dynamics and Vulnerability of Hydrogeomorphological Units to the Degradation of Climatic Conditions in the Watershed of the Birnin Lokoyo Pond (Iullemmeden Basin, Southwestern Niger)

The present study concerns the lowlands of the Birnin Lokoyo watershed located in the Matankari Rural Commune (Southwestern borders of the large Iullemmeden basin in the Niger). Dominated by the Birnin Lokoyo pond, this watershed faced with the continuous silting up of the minor bed, dissipates further upstream in the east, so that it moves downstream to the west for the benefit of the populations of Matankari city. The main objective of this work is to analyze the representative elements of the new climatic and environmental situation as well as the various factors determining the surface conditions in the watershed. The methodological approach is based on documentary research, field observations, individual surveys and interviews with targeted groups. The results show that the silting up of the lowlands is the result of the concomitant degradation of the plant cover and the soils, which, as a result, triggered the development of crusting surfaces and area erosion on the slopes. The study underlined the importance of endogenous knowledge in the choice of remedies against the silting up of lowlands. In addition, rational land management practices on plateaus and structures (within the watershed) do not seem to be in phase with topographical factors and the tectonic framework. This work is part of the vision of better management of glacis on the banks, but also of sills subject to regressive erosion upstream and in order to guide the policies of resilience of the populations.

Pendekatan Hidrogeomorfologi Dan Pendugaan Geolistrik Untuk Identifikasi Potensi Airtanah Di Jedong Malang

This study aims to identify the potential groundwater in Jedong, Malang, East Java. The hydrogeomorphological approach is a suitable approach to describe the relationship between hydrological and geomorphological processes on and below the earth's surface. The survey of geoelectricity complements the hydrogeomorphological approach. It will give a better description of the groundwater conditions below the earth's surface. Based on the research, there are 2 hydrogeomorphological units in the study area, which are: Volcanic Foot Valley Unit and Volcanic Foot Ridge Unit. The best groundwater potential is in Volcanic Foot Valley Hydrogeomorphological unit, namely Awar-awar Valley and Cokro Valley. The valleys are dominated by gully erosion and landslides. They have surface deposits up to a depth of 7 meters, and lots of outcrops of breccia, pumice, and andesite boulders. The valley’s springs discharge between 56 - 198 m3/day. The average infiltration rate in the valley is 1776 mm / hour, with sandy soil material. The best aquifer consisting of sandy material is more than 10 meters in depth, based on the geoelectrical survey. Water in the aquiclude layer, cannot be exploited because it is breccia and tuff material. The Sawah valley cannot be exploited further because the groundwater potential is very low. This can be identified by the thick water outflow seepage. In the Volcanic Foot Ridge Hydrogeomorphological unit, the groundwater potential is also very small. Hydrogeomorphically, water will flow down the slope to the valley. It will reduce the infiltration rate. In general, the ridge area is only used for settlement, while the slopes are used for dryland agriculture. The geoelectric analysis results show that the groundwater potential is at a depth of more than 45 meters. This research’s results show that the combination of the hydrogeomorphological approach and the geoelectric use will provide a better description of the potential groundwater.

Groundwater Occurrence from Hydrogeomorphological Study of Hard Rock Terrain of Part of Southwestern Nigeria

Abstract Studies of structural and hydrogeomorphological units (HGU) that are indicators of groundwater occurrence were carried out across an area extent of more than 700 km2 within the hard rock terrain of southwestern Nigeria. These studies integrated geological remote sensing techniques (RST) and geographical information system (GIS) methods to generate thematic maps that included elevation, drainage, lineaments and vegetation index for characterising the attributes of groundwater occurrence across the area. The results revealed that the lineament system is mainly rectilinear with major trends of NNW-SSE and NE-SW on the gneiss, NW-SE and NE-SW on porphyritic granite and NNE-SSW, NW-SE and E-W on migmatite. The discharge zones in the area are the lowland terrains underlain by gneiss and amphibolite. Similarly, variably directional discontinuities that are related to rock contacts are equally laden with groundwater. Conversely, the recharge areas are the high-lying terrains characterised by higher fracture density and underlain by porphyritic granite and migmatite. Additionally, there are evidences of groundwater seepage along the major river channels. Therefore, besides the rock structures, landform is another crucial factor that guides groundwater distribution in the study area.

Hydro-geomorphic controls on the development and distribution of acid sulfate soils in Central Java, Indonesia

Coastal planning policies and regulations in Indonesia have not adequately considered acid sulfate soils (ASS) as a constraint on development. Aquaculture is often undertaken in unsuitable areas, and fish and shrimp culture systems, in particular, fail after a short period of production because of the impacts of ASS on pond water quality and, subsequently, on fish and shrimp health. This study describes a mapping approach based on an understanding of the hydro-geomorphic controls on the formation and the distribution of ASS in Central Java, Indonesia. The underlying approach was to identify associations between ASS development and distribution within estuarine hydro-geomorphological units (HGUs). This study utilized a multi-level methodology involving multi-resolution, remotely-sensed data and GIS analysis, coupled with field and laboratory-based data, to obtain hydro-geomorphic and soil information at different mapping scales. An estuary classification scheme for Central Java identified river, tide and wave-dominated estuaries as the dominant estuary types. HGUs were identified in each estuary type to define the relationships between landform development processes and pyrite concentration in soil layers. Thirty-nine HGUs were classified based on landforms, marine and fluvial hydrology, geomorphic processes, land use, and vegetation types. Field and laboratory assessment of soil properties were undertaken to identify the horizontal distribution of ASS in the HGUS and its vertical character in soil profiles. In contrast to previous studies, the results showed that estuaries located in low-energy environments on the north coast have low (<0.1%) pyrite concentrations in 90% of their HGUs. Decades-old intensive aquaculture and dredging activities, that led to repeated oxidation and leaching, were identified as factors for low pyrite concentrations. On the south coast, the combination of a high river and marine energy environment created scattered landforms with soils that have very high (4–9%) pyrite concentrations. These ASS-bearing HGUs mostly developed in low- energy estuarine environments overlying former high river energy environments. The information generated for each HGU facilitated the development of an ASS mapping model that incorporates knowledge on the relationship between soil and landform formation in Central Java estuaries. Knowing where ASS occur is essential to minimize the risk of environment degradation. Using multi-resolution, remotely sensed data decreases cost and labour, compared to more traditional mapping approaches, especially to identify sampling sites for field surveys. The resulting maps and mapping methods will improve land capability assessment for brackishwater aquaculture and other coastal land use in Indonesia.

Mapping of groundwater potential zones in Killinochi area, Sri Lanka, using GIS and remote sensing techniques

Groundwater is a vital natural capital for the consistent and economic provision of potable water supply for both rural and urban environments. There is now a strong consensus that climate change poses a fundamental challenge to the well-being of all countries, with potential of being the harshest on countries already suffering from water scarcity. Dry zone of Killinochi basin in Northern Sri Lanka, which was devastated by civil war for last 25 years, is again being revitalized by human settlement and urbanization in last couple of years. However, the decreasing trend in the rainfall regime of the dry zones and the increase in population size (temporary inflow) and, hence, the demand for water for irrigation and other livelihood requirements, calls for a sustainable exploitation of the groundwater resources in the region. The development of a reasonable model for groundwater potential is need for the present time. This work strives to generate groundwater potential zonation map using integrated use of remote sensing and geographic information system (GIS) for Killinochi area, Northern Sri Lanka. Five different themes of information, such as geomorphology, geology, soil type (extracted from existing topo sheet); slope [generated from shuttle radar topography mission (SRTM) digital elevation model (DEM)]; and land use/land cover (extracted from digital processing of AVNIR satellite data) were integrated with weighted overlay in GIS to generate groundwater potential zonation map of the area. The final map of the area was demarcated by four different zones of groundwater prospects, viz., good (5.32 % of the area), moderate (61.90 % of the area) poor (26.61 % of the area), and very poor (6.17 % of area). The hydrogeomorphological units, such as alluvial plain, low slope area, and land occupied by forest, are prospective zones for groundwater occurrence in the study area.

Trace element release patterns from three floodplain soils under simulated oxidized–reduced cycles

River-floodplain ecosystems are long-term sinks for certain contaminants. Fluctuations between flooding and drying are major drivers of spatial and temporal changing biogeochemical processes within floodplain soils. Even small changes of the frequency, magnitude, and timing of drying and rewetting can episodically turn those ecosystems into a source for matter. To understand such changes we investigated the effects on top soils of three hydro-geomorphological units that are typical for floodplains: depression, levee, and plateau. They show distinct characteristics regarding soil type, trace element (TE) pollution level and hydrology. In the laboratory we used an automated biogeochemical microcosm set up to simulate oxidized–reduced cycles to monitor the effects of strong fluctuating redox potential (EH), on pH, iron (Fe), manganese (Mn), sulfur (S), nitrate (NO3), dissolved organic carbon (DOC) and dissolved concentrations of arsenic (As), cadmium (Cd), copper (Cu), chromium (Cr), nickel (Ni), and zinc (Zn) in the soil solution. The results indicated different responses regarding the course of EH/pH and different release patterns of TEs for each hydro-geomorphological unit separately. Both could be mainly allocated to their explicit spatial characteristics; due to differences in its buffer capacities and to the interaction between pH-value and microbial activity. In particular, we could demonstrate that a combination of several biogeochemical factors may influence TE release or retention in floodplain soils by means of generalized additive models (GAMs). Using those, Fe and S were identified as most important factors that determined the dynamics of TEs in all three studied soils; concentrations of As, Cu, Cr, Ni, and Zn increased with increasing Fe-concentrations whereas Cd, Cu, Cr, Ni, and Zn seem correspondingly to be dependent on S that went along with the course of the oxidized–reduced cycle. Still, several uncertainties between environmental changes and TE release from floodplain soils may exist. Thus, the fate of dissolved TEs in river-floodplain ecosystems needs to be taken under serious consideration since the ecotoxicology threat of them is of undisputed risk.

Basin geomorphology and drainage morphometry parameters used as indicators for groundwater prospect: Insight from geographical information system (GIS) technique

Influence of structural and lithological controls of various drainage patterns and their stream orientations (for 2nd, 3rd and 4th order steams) were identified to evaluate the direction and controlling factors of drainage network. To investigate the prospect of groundwater, hydrogeomorphological features of river basin viz. Mulki-Pavanje were identified and mapped. To evaluate the characteristics of the basin, different morphometric parameters (linear, areal and relief) were computed in sub-basin wise (SB-I to -VII). The linear parameters suggest drainage network is controlled by geomorphology. The form factor (F f), elongation ratio (R e) and circularity ratio (R c) suggest that the basin is in an elongated shape. The drainage density (D d) indicates resistant/permeable strata under medium-dense vegetation with moderate relief. The areal parameters of the sub-basins (except SBI and III) indicates moderate ground-slopes associated with moderately permeable rocks, which promote moderate run-off and infiltration. Drainage texture (T) of the whole basin indicates coarse texture while the SB-I, and III showing an intermediate texture. The relief parameters namely ruggedness number (R n ) infers low basin relief and poor drainage density. To identify the most deficit/surplus zones of groundwater suitable weightages were assigned to the hydrogeomorphological units and morphometric parameters. The study reveal that the basin manifest that SB-III shall be most deficit zone of groundwater, whereas SB-VII, VI and V are found to show increase in groundwater potentiality. Groundwater prospect area in this basin is estimated to be 7% area under poor, 44% area under moderate and 49% area under good to excellent. This paper demonstrated the potential application of geographical information system (GIS) techniques to evaluate the groundwater prospect in absence of traditional groundwater monitoring data.

Identification of Groundwater Potential Zones of a Tropical River Basin (Kerala, India) Using Remote Sensing and GIS Techniques

The present work accentuated the expediency of remote sensing and geographic information system (GIS) applications in groundwater studies, especially in the identification of groundwater potential zones in Ithikkara River Basin (IRB), Kerala, India. The information on geology, geomorphology, lineaments, slope and land use/land cover was gathered from Landsat ETM + data and Survey of India (SOI) toposheets of scale 1:50,000 in addition, GIS platform was used for the integration of various themes. The composite map generated was further classified according to the spatial variation of the groundwater potential. Four categories of groundwater potential zones namely poor, moderate, good and very good were identified and delineated. The hydrogeomorphological units like valley fills and alluvial plain and are potential zones for groundwater exploration and development and valley fills associated with lineaments is highly promising area for groundwater extraction. The spatial variation of the potential indicates that groundwater occurrence is controlled by geology, structures, slope and landforms.

Groundwater prospects evaluation-based on hydrogeomorphological mapping: A case study in Kancheepuram district, Tamil Nadu

Water is the most important natural resource which forms the core of the ecological system. The advent of remote sensing has opened up new vistas in groundwater prospect evaluation, exploration and management. The role of hydrogeomorphological units in tile storage of groundwater from the Kancheepuram distict has been investigated using IRS P6 LISS-III data. The Kancheepuram district exhibits diverse hydrogeomorphological conditions where the groundwater regime is controlled mainly by topography and geology. The extent of various water prospectus zones in terms of percentage includes, maximum area, particularly the north-western, and central part which is characterized by good potential occupying about 43% of total area. The moderate potential is marked by only 35%, and is scattered along the northern and southern side of the study area, the remaining 12% is of poor prospectus, which is falling in the coastal region of the study area.

Identification of groundwater prospective zones using irs-id liss iii and pump test methods

The role of hydrogeomorphological units and lineaments in the storage of groundwater from the Muvattupuzha river basin has been investigated using IRS ID LISS III data. Other than the usual water bodies such as river course, reservoirs and ponds, the major hydrogeomorphological units identified in this basin in the descending order of their groundwater potential are: valley fills, moderately dissected plateau, pediments, residual mounts, residual mount complex, linear ridges, residual hills and structural hills. Majority of the lineaments trends in NW-SE and WNW-ESE directions. Even though the eastern part of the basin is characterised by moderate to high lineament density, the above area is found to be poor to moderate groundwater prospect zone because of high gradient and structural hills. The pump test analyses of dug wells from different hydrogeomorphic units also confirm that valley fills are the most promising unit for groundwater prospecting than the rest.

Influence of rock types and structures in the development of drainage network in hard rock area

Remote sensing techniques has proved to be an extremely useful tool in morphometric analysis and groundwater studies. Remote sensing techniques with an emphasis on lineament identifications can play a great role in groundwater prospecting in semi-arid hard rock areas of Purulia district. In the present study, morphometric analysis using remote sensing technique has been carried out in parts of Baghmundi block, Purulia district, West Bengal. The parameters worked out include Bifurcation ratio (Rb), Stream length (Lu), Form factor (Rc), Circulatory ratio (Rc), and Drainage density (D). The morphometric analysis suggests that fractured, resistant, permeable rocks cover the area, the drainage network not so affected by tectonic disturbances. Using satellite imageries of two dates of IRS, different hydrogeomorphological units have been delineated. Among different hydrogeomorphic units (i) very shallow weathered pediment and (ii) Structural hills/ residual hills/inselbergs have very poor ground water prospects, while moderately weathered pediplains and valley fills are good prospective zones for groundwater exploration.

Mapping of hydrogeomorphological features in varaha river basin using IRS data

Hydrogeomorphological mapping in Varaha River Basin (VRB) was carried out to develop relationship between groundwater condition and geomophology of the area. The VRB is located in the north coastal region of Andhra Pradesh is characterised by variability in precipitation, temperature, vegetation, infiltration and run-off. Realising the significance of remote sensing in natural resource management and development, IRS 1A data was used in the study. It is inferred that various hydrogeomorphological units identified in the study area, are the outcome of different geomorphic processes that have been operating in the area and reveal which close relationship between groundwater condition and geology and geomorphol-ogy of the area. Areas covered by buried channels have shallow aquifers of good quality wa-ter with excellent yield. Lineaments and fractures may prove to be potential zones for ground-water development.

Groundwater assessment through hydrogeomorphological and geophysical survey — A case study in Godavari sub-watershed, Giridih, Bihar

Groundwater assessment has been carried out through hydrogeomorphological and geophysical survey. Remotely sensed data has been used to delineate the hydrogeomorphological units. Each hydrogeomorphological unit has been further sub-divided based on the tone, texture and pattern. These units its have been categorised based on depth of weathering, local geomorphological association, recharge characteristics etc. The top layer resistivity of hydrogeomorphological units has been analysed by electrical resistivity method. Correlation between different sub-units of same hydrogeomorphic unit and top soil resistivity has been attempted. The correlation and integration of resistivity map with geomorphological map were carried out through. ‘GRAM’ Geographic information System, This has helped in better understanding the surface resistivity pattern.

Hydrogeomorphological mapping of Jaisalmer and Bikaner districts (Rajasthan) at 1 : 50,000 scale using satellite data

Jaisalmer and Bikaner districts of Rajasthan, in the Thar Desert, experience perpetual shortage of water due to scarce and erratic rainfall and high evapotranspiration. Aeolian topography not only renders some stretches of these districts inaccessible but also conceals geological formations (thick sand cover) making it difficult to infer groundwater prospects of the region. However, by preparing hydrogeomorphological maps using remote sensing data, delineation of promising groundwater prospective zones can be carried out. Such mapping using IRS LISS II and SPOT imagery was carried out at 1:50,000 scale for the two districts of Jaisalmer (80 maps) and Bikaner (61 maps). The mapping improved classification as well as locational accuracy of various hydrogeomorphological units as compared to earlier maps prepared on 1:250,000 scale. In Jaisalmer and Bikaner districts 21 and 18 hydrogeomorphological units, respectively, were delineated. Significant hydrogeomorphological units, their distribution and groundwater prospects are discussed in this paper.

Evaluation of ground water potential in the environs of Jhansi city, Uttar Pradesh using hydrogeomorphological assessment by satellite remote sensing technique

An attempt has been made to delineate different hydrogeomorphological units in and around the immediate environs of Jhansi city with a view to attempt a correlation between the well yields and hydrogeomorphic units using satellite remote sensing technique. In general, a positive correlation is observed between the geomorphic units and the borewell yields with overlapping yields at the margin. The pediment residual hill complex is observed to provide wells with discharges ranging from 100 gallons per hour (gph) to 5000 gph, while the wells drilled in shallow weathered, buried pediplain has yields in the range of 2000 to 10000 gph moderately weathered, buried pediplain has discharges in the range of 8000 to 12000 gph, and deeply weathered, buried pediplain has discharges in excess of 12000 gph.

Visual interpretation of F.C.C. satellite data for channel migration and water logging conditions along Ghaghra and Terhi rivers in part of district Gonda and Bahraich, U.P.

The conventional visual interpretation of landsat Imagery is potentially the most useful remote sensing tool for the study of channel migration & water logging conditions at different time spans; which were earlier not easy due to non availability of suitable evidences. The present study brings out, in exact terms & the extent of the utility of the false colour and black and white landsat data. The application of the false colour scanning method is also useful remote sensing tool for the study of direct & indirect hydrogeological regime by visual interpretation technique. The spectrum are favourable for detection of surface phenomenon, which is associated with the subsurface ground water environment. An area of about 3,500 Sq.Km. of U.P. along left bank of Ghaghra river and right bank of Terhi rivers have been taken for the study. The paper was designed to evaluate the fluvial action and ground water environments with the help of repetitive landsat data in ten years. The fluvial action of Ghaghra and Terhi rivers have been mainly contributing to the development of hydrogeomorphological units which have given exact references regarding fluctuation in hydrogeomorphological units and water logging with hydrological response of the ground water environment, by using landsat data of 1975 & 1984. Further the direct relationship between remote sensing measurement and physical properties of hydrogeological environments is brought out in the maps.