Morphometric analysis of Rasyan valley basin - A case study in the Republic of Yemen, using Remote Sensing and GIS techniques

Remote Sensing and GIS has given more importance for investigation of the geomorphological features based on the morphometric analysis duo to the diversity of data information by using digital map characters which help in moderating of data base information to get a different data like distance, area, point, line, polygon and qualitative data. This has decreased the errors which resulted by manual map sources. The main aim of this paper is the study of a morphometric analysis and characteristics of river basin area, basin shape, length, width and the ratio of length to the width, the ratio of rotation and circularity of the basin. It is also a study of relief characteristic, like slope and basin texture hypsometric curve. And also a study of drainage network characteristic like streams, stream order, length, drainage density, turn ratio, bifurcation ratio, weighted bifurcation ratio, type of drainage, and the relationship between all variables that mentioned above with rock types and structural movements of internal and external factors which are represented by relief, climate, soil, type of vegetation along with the human impact on the other hand. Results have been discussed for Rasyan valley basin in the Republic of Yemen using Landsat data.

Geo-informatics based Morphometric Analysis of a Reservoir Catchment in Shivalik Foothills of North-West India

The present study examined 35 morphometric parameters related to stream/drainage network, catchment geometry, and relief aspects for hydrological characterization of the Thana Dam catchment using geospatial tools and techniques. The dam catchment was delineated using the high-resolution Advanced Land Observing Satellite Phased Array type L-band Synthetic Aperture Radar (ALOS PALSAR) Digital Elevation Model (DEM) data in ArcGIS 10.4.1 software using the Arc Hydro tools. The catchment is comprised of 4th order stream, obtained using a stream threshold value of 100 m length. The lower values of elongation ratio (0.61), circularity ratio (0.22), and form factor (0.29) indicated higher soil erosion potential, mainly due to their inverse relationship with land erodibility. Moreover, the higher values of stream frequency (15.7), drainage density (>5.0), drainage texture (7.48 km-1), and mean bifurcation ratio (4.08-6.33) indicated higher runoff potential, which would intensify the soil erosion, mainly due to their direct relationship with erodibility. Bifurcation ratio, elongation ratio, circulatory ratio, form factor, altogether indicated an elongated shape of the catchment with a fine drainage texture. The higher values of bifurcation ratio and texture ratio of the catchment also indicated severe overland flow (low infiltration rate) with a limited scope for groundwater recharge in the area, which in turn might significantly encourage the soil erosion. Overall, it was concluded that the catchment has a huge runoff potential resulting in high soil erosion due to its fine texture, impermeable subsurface material, steep slope, low infiltration rate, limited vegetation, longer duration of overland flow, and higher surface runoff. The morphometric analysis was found to be suitable for identifying catchment shape and the factors affecting hydrologic conditions and erodibility of the catchment. Thus, Geo-informatics based morphometric analysis of a reservoir catchment can be useful to study the erosion potential in relation to hydrologic (rainfall-runoff relationship) and other related land characteristics (e.g., relief, slope, infiltration rate, etc.).

Morphometric analysis of a drainage basin using geographical information system in Gilgel Abay watershed, Lake Tana Basin, upper Blue Nile Basin, Ethiopia

GIS and remote sensing approach is an effective tool to determine the morphological characteristics of the basin. Gilgel Abay watershed is stretched between latitude 10.56° to 11.22° N and longitude 36.44° to 37.03° E which is one major contributing river of Lake Tana which is the source of Blue Nile. The present study addressed linear and areal morphometric aspect of the watershed. The study deals with emphasis on the evolution of morphometric parameters such as stream order, stream length, bifurcation ratio, drainage density, stream frequency, texture ratio, elongation ratio, circularity ratio, and form factor ratio. The morphometric analysis of the basin revealed that Gilgel Abay is firth-order drainage basin with total of 662 drainage network, of which 511 are first order, 111 are second order, 30 are third order, 9 are fourth order, and 1 is fifth-order stream. The total length of stream is longer for first order and decrease with increasing stream order. The mean bifurcation ratio is 5.16 which is greater than the standard range, and it indicates that basin is mountainous and susceptible to flooding. Low drainage density is observed which is 0.6 km−2. It indicates that basin is highly permeable and thick vegetation cover. Areal aspect of the morphometric analysis of the basin revealed that the basin is slightly potential to flooding and soil erosion, indicating that runoff generated from the upland area of the watershed is significantly infiltrated at the gentle downstream part and contributing to groundwater potential. Further studies with the help of GIS and remote sensing with high-resolution remote sensing data integrating with ground control data in the field are more effective to formulate appropriate type of natural resource management system.

Morphometric and Sinuosity Analysis of Tlawng River Basin: A Geographic Information System Approach

Channel plan-form patterns of river Tlawng has been studied which shows that there is variation in the sinuosity index. This variation is a sign of changing characteristics and behavior of the river. The average sinuosity of the river is 1.41. The sinuosity index is higher in the lower course of the river as it flows through alluvial plain. GIS techniques have been used for studying morphometric parameters. There are 6736 streams in the Tlawng river basin which shows that the topography is still undergoing erosion as the number of stream is high (Zaidi, 2011). The river has low bifurcation ratio which indicates less possibilities of flooding. The drainage density indicates the higher permeable subsoil and moderate to thick vegetative cover. The stream frequency value of the Tlawng river basin is 1.30 streams / km2 which shows a positive relation with drainage density.

Quantitative Analysis of a River Basin - A GIS-based Approach

The river basin plays a fundamental role in planning the management of natural resources. The hydrological behavior of the basin depends on the geomorphological parameters of the hydrographic basin. In the present study, a morphometric analysis was performed to determine the linear, areal and relief parameters of the Panzara River, the main tributary of the Tapi River, using the Geographic Information System tool. The river basin is of seventh order, showing a dendritic pattern of drainage that indicates the homogeneity in the texture of the basin. The drainage density in the area is 2.56 and the mean bifurcation ratio 5.065 indicates the less impact of structural deformations on the basin. The stream frequency of the basin is 3.20 showing low relief and high permeability. The present study reveals that the applications of GIS techniques are reliable, take less time and are competent to manage large databases for management of river basins.

Quantitative Analysis of Geomorphologic Characteristics for Surface Runoff Determination in Amala River Catchment in Kenya

Hydrological response of a catchment is a function of rainfall as influenced by catchment characteristics comprising geomorphology, land cover, and management practices. In this study, the analysis mainly focused on how geomorphological characteristics influence the catchment hydrological response. Geomorphological analyses of catchment geometry, stream patterns, relief, and slope can be used to characterize the catchment features that affect the drainage network. These characteristics are catchment specific and therefore unique to provide an insight into its hydrologic response. The objective of this research was to quantitatively analyze geomorphologic characteristics; linear, areal, drainage pattern, and relief aspect, of Amala River catchment, using ArcGIS tools and infer its hydrological behavior. The morphometry of the catchment was derived from the DEM within the ArcMap environment. These parameters as well as mathematical map equations were used to derive geomorphological characteristics such as bifurcation ratio, rho coefficient, drainage density, infiltration number, form factor among others. The results show that the Amala River catchment is elongated with uniform lithology and a higher probability of delayed peak hydrographs due to longer lag time and time of concentration. The catchment exhibits a dendritic drainage pattern with an average bifurcation ratio of 4.26 which is closer to the upper bound value of 5. This indicates a reduction in peak flows and a delayed time to peak. The surface runoff yield efficiency was low and non-uniform with an average drainage density of 1.073 km/km2. The catchment was characterized by higher infiltration characteristics as compared to surface flows, this varied spatially, with sub-basins far North of the outlet having high infiltration than those near the outlet. The catchment relief was characterized as steep and therefore high stream velocity was inferred. The investigation and findings of this study on catchment geomorphology and inferred hydrologic behavior will be of great importance in catchment management, water resource planning within the catchment, and water harvesting at a spatial scale. Thus, the outcomes provide a baseline for informed water pan and water harvesting structures site.

The Study of the Linear Morphometry of Suktel River Basin, Odhisha

In the present study, an attempt is made to study the linear morphometry of Suktel River, a tributary of Tel River and its sub basins, that flows through Bolangir District of Odisha. Freely available SRTM Dem (30-meter resolution) has been processed to delineate the streams and the watershed. Its various linear parameters have been delineated using Arc GIS 10.3. The results show that Suktel basin is a sixth-order normal basin having a dendritic drainage pattern. It confirms to Horton's Law of stream number and lacks structural control as implied by its bifurcation ratio that ranges between 3 and 5. It is in the stage of late maturity with the high volume of surface discharge.

Morphometric Analysis of a Drainage Basin: A Study of Ghatganga River, Bajhang District, Nepal

This study attempts to study the morphometric characteristics of the Ghatganga basin by using Geographical information system (GIS). This analysis has shown that the relation of stream order (U) and stream number (Nu) which gives a negative linear pattern that order increases with a decreasing number of stream segment of a particular order. Different morphometric parameters such as stream length (Lu), bifurcation ratio (Rb), drainage density (D), stream frequency (Fs), texture ratio (T), elongation ratio (Re), circularity ratio (Rc), form factor ratio (Rf), relief ratio (Rh) and river profile have revealed the basin has a dendritic pattern of drainage, indicating high relief and steep ground slope with less elongated young and mature landforms in which geological structures don’t have a dominant influence on the basin.

MODELS TO PREDICT SLOPE LENGTH FROM OTHER WATERSHED ATTRIBUTES

Soil erosion by water is an extensive and increasing problem worldwide. Albeit, this problem has been recognized as a significant hazard in Iraq, yet the number of studies on this topic is very limited. Most of the models used for estimating soil erosion contain parameters for slope length factor (LS). A major constraint is the difficulty in extracting the LS factor. Accordingly, the current study was initiated with the main objective of deriving models to predict the slope length from relatively easy to measure basin characteristics with a reasonable accuracy. To achieve the above objective, standard methodologies were employed to describe 30 main basins with the upper part of Iraq in terms linear, areal and relief morphometric parameters. The majority of the delineated watersheds were characterized by having high slope lengths indicating lower drainage density and higher erosion rate. Linear and non-linear least squares techniques were applied to predict the slope length from other basin characteristics. Different indicators were used to test the performance of the proposed models and the approach was validated using K-fold procedure at independent basins. The results indicated that the 4-parameter regression model outperformed the remaining models of watershed slope length. The regressors of this model are bifurcation ratio, perimeter, and basin length and slope gradient.

Morphometric Analysis of Ken River Basin through Remote Sensing and GIS Techniques

Management of water resources required assessment of morphometric parameters in order to enhance the capability of understanding the factor which may help to render the impact caused due to high flood due to inadequate water disposal management. In the present study computation of linear, aerial and relief aspects viz., bifurcation ratio, mean bifurcation ratio (Rbm), mean stream length (Lum), stream length ratio (Rl), form factor (Ff), circularity ratio (Rc), stream frequency (Fs), drainage density (Dd), dissection index (Di), ruggedness index (Ri) has been carried out in order evaluate watershed characteristics for soil conservation and watershed management. The basin poses a high flood potential risk due to inadequate drainage and less channel development. The Ken river basin is elongated in shape as indicated by the computation of form factor with comparatively less value. Due to inadequate drainage patterns for safe disposal of surplus water, the vulnerability to water erosion can be considered as a major cause of concern in the Ken river basin. Evaluation of relief aspects suggested the existence of intense flood characteristics within the basin during period of heavy rainfall. Assessment using remote sensing and GIS approach can prove as an effective tool for analyzing properties of basin and for sustainable management of available water resources with exercise of suitable sites selection for development of structure to control runoff and adaptation of conventional methods for water conservation, thus increasing infiltration rate with decreased surface runoff and erosion.