首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 781 毫秒
1.
GIS and Remote Sensing have proved to be an indispensible tool in morphometric analysis. The identification of morphometric properties based on a geographic information system (GIS) was carried out in two watersheds in the Thrissur district of Kerala, India. These watersheds are parts of Western Ghats, which is an ecologically sensitive area. Quantitative geomorphometric analysis was carried out for the Chimmini and Mupily watersheds independently by estimating their (a) linear aspects like stream number, stream order, stream length, mean stream length, stream length ratio, bifurcation ratio, length of overland flow, drainage pattern (b) aerial aspects like circulatory ratio, elongation ratio, drainage density and (c) relief aspects like basin relief, relief ratio, relative relief and ruggedness number. The drainage areas of Chimmini and Mupily watersheds are 140 and 122 km2 respectively and show patterns of dendritic to sub-dendritic drainage. The Chimmini watershed was classified as a sixth order drainage basin, whereas Mupily watershed was classified as a fifth order basin. The stream order of the basin was predominantly controlled by physiographic and structural conditions. The increase in the stream length ratio from lower to higher order suggests that the study area has reached a mature geomorphic stage. The development of stream segments is affected by rainfall and local lithology of the watersheds. The slope of both watersheds varied from 0° to 50° and 0° to 42° respectively and the slope variation is chiefly controlled by the local geology and erosion cycles. Moreover, these studies are useful for planning rain water harvesting and watershed management.  相似文献   

2.
A morphometric analysis was carried out to describe the topography and drainage characteristics of Papanasam and Manimuthar watersheds. These watersheds are part of Western Ghats, which is an ecologically sensitive region. The drainage areas of Papanasam and Manimuthar watersheds are 163 and 211 km2, respectively and they show patterns of dendritic to sub-dendritic drainage. The slope of both watersheds varied from 0° to 59° and 0° to 55°, respectively. Moreover, the slope variation is chiefly controlled by the local geology and erosion cycles. Each watershed was classified as a fifth-order drainage basin. The stream order of the basin was predominantly controlled by physiographic and structural conditions. The increase in stream length ratio from lower to higher order suggests that the study area has reached a mature geomorphic stage. The development of stream segments is affected by rainfall and local lithology of the watersheds.  相似文献   

3.
The study area is a one of the sub-basin of Vaigai River basin in the Theni and Madurai districts, Western Ghats of Tamil Nadu. The Vaigai sub-basin extends approximately over 849 km2 and it has been sub-divided into 48 watersheds. It lies between 09°30′00″ and 10°00′00″N latitudes and 77°15′10″ and 77°45′00″ E longitudes in the western part of Tamil Nadu, India. It originates at an altitude of 1661m in the Western Ghats of Tamil Nadu in Theni district. The drainage pattern of these watersheds are delineated using geo-coded Indian remote sensing satellite (IRS) ID, linear image self-scanning (LISS) III of geo-coded false colour composites (FCC), generated from the bands 2, 3 and 4 on 1:50,000 scale in the present study. The Survey of India (SOI) toposheets 58G/5, 58 G/6, 58G/9 and 58G/10 on a scale of 1:50,000 scale was used as a base for the delineation of watershed. In the present study, the satellite remote sensing data has been used for updation of drainages and the updated drainages have been used for morphometric analysis. The morphometric parameters were divided in three categories: basic parameters, derived parameters and shape parameters. The data in the first category includes area, perimeter, basin length, stream order, stream length, maximum and minimum heights and slope. Those of the second category are bifurcation ratio, stream length ratio, RHO coefficient, stream frequency, drainage density, and drainage texture, constant of channel maintenance, basin relief and relief ratio. The shape parameters are elongation ratio, circularity index and form factor. The morphometric parameters are computed using ESRI’s ArcGIS package. Drainage density ranges from 1.10 to 4.88 km/km2 suggesting very coarse to fine drainage texture. Drainage frequency varies from 1.45 to 14.70 which is low to very high. The bifurcation ratio ranges from 0.55 to 4.37. The low values of bifurcation ratios and very low values of drainage densities indicate that the drainage has not been affected by structural disturbances and also that the area is covered under dense vegetation cover. Elongation ratio ranges from 0.11 to 0.57. Drainage texture has the minimum of 1.63 and maximum of 11.44 suggesting that the drainage texture is coarse to fine. It is concluded that remote sensing and GIS have been proved to be efficient tools in drainage delineation and updation. In the present study these updated drainages have been used for the morphometric analysis.  相似文献   

4.
Land and water resources development plans are generally adopted at watershed level. Delineation of watersheds and their prioritization within large river basins requires host of terrain parameters to be studied and analysed. Chopan watershed in Central India has been studied for sub-watershed delineation and prioritization based on drainage morphometry, land use/land cover and sediment yield index analysis using remote sensing and GIS techniques. The watershed was demarcated into five sub-watersheds on the basis of drainage flow directions, contour value, slope, elevation. Geocoded satellite data of 1989 and 2001 on 1:50 000 scale were visually interpreted to prepare land use/land cover and drainage maps which were later digitized using Arcview/ArcGIS. Linear and shape aspects of the sub-watersheds were computed and used for prioritization. The results show widespread variation in drainage characteristics, land cover changes and sediment yield rates across sub-watersheds. On the basis of morphometric, land use/land cover change and sediment yield index, sub-watersheds were grouped into low, medium and high priority. A correlation of results show that SW1 and SW5 are common sub-watersheds falling under high and low priority based on morphometric, land use change analysis and SYI. The priority list of sub-watersheds will be crucial for decision making and implementation of land and water resource conservation projects.  相似文献   

5.
In this study, a digital elevation model was used for hydrological study/watershed management, topography, geology, tectonic geomorphology, and morphometric analysis. Geographical information system provides a specialized set of tools for the analysis of topography, watersheds, and drainage networks that enables to interpret the tectonic activities of an area. The drainage system maps of Zagros Mountains in southwest Iran have been produced using multi-temporal datasets between 1950 and 2001 to establish the changes between geomorphic signatures and geomorphic aspect during time and to correlate them with recent neo-tectonics. This paper discusses the role of drainage for interpreting the scenario of the tectonic processes as one of important signatures. The study shows variation in drainage network derived from topography maps. Thus, changes in drainage pattern, stream length, stream gradient, and the number of segment drainage order from 1950 to 2001 indicate that Zagros Mountain has been subjected to recent neo-tectonic processes and emphasized to be a newly active zone.  相似文献   

6.
An attempt to carry out morphometric, statistical, and hazard analyses using ASTER data and GIS technique of Wadi El-Mathula watershed, Central Eastern Desert, Egypt. Morphometric analysis with application of GIS technique is essential to delineate drainage networks; basin geometry, drainage texture, and relief characteristics, through detect forty morphometric parameters of the study watershed and its sub-basins. Extract new drainage network map with DEM, sub-basin boundaries, stream orders, drainage networks, slope, drainage density, flow direction maps with more details is very necessary to analyze different morphometric and hydrologic applications for the study basin. Statistical analysis of morphometric parameters was done through cluster analysis, regression equations, and correlation coefficient matrix. Clusters analyses detect three independents variables which are stream number, basin area, and stream length have a very low linkage distance of 0.001 (at very high similarity of 99.95%) in a cluster with the basin width. Main channel length and basin perimeter (at very high similarity of 99.83%) are in a cluster with basin length. Using the regression equations and graphical correlation matrix indicates the mathematical relationships and helps to predict the behavior between any two variables. Hazard analysis and hazard degree assessment for each sub-basin were performed. The hazardous factors were detected and concluded that most of sub-basins are classified as moderately to highly hazardous. Finally, we recommended that the flood possibilities should be taken in consideration during future development of these areas.  相似文献   

7.
An integrated morphometric and hypsometric analysis coupled with asymmetric factor used as a proxy for the landscape evolution of the catchment of Karuvannur River. The present study area is a sixth order tropical river in the central Kerala which supplies water and sediments to the Vembanad-Kol Ramsar site. The Karuvannur River Basin (KRB) has been divided into six sub-watersheds (SW). Morphometric parameters (areal, linear, and relief) and hypsometric and asymmetric factors are measured for the delineation of morphotectonic evolution of the area. High values of drainage density, texture, ruggedness number, and hypsometric integral with relatively high volume of leftover rocks in the basin in SW-II and SW-III compared to the entire basin of KRB imply that these two sub-watersheds have been influenced by the tectonic activities. Further, detailed asymmetric data indicated that these two watersheds are tilted in opposite direction. It may be the result of reactivation of Precambrian fault/lineament in recent past. This has been supported by recent tremors and neotectonic studies in Kerala. Moreover, detailed field evidence along with google imagery revealed that the entire basin is a part of regional anticline associated with PCSZ. Geomorphic response to disturbance will produce a sensible, recognizable response; it can be well studied in rivers through detailed study of their sensitivity or behavioral changes. Rivers have an enormous capacity to absorb perturbation and these types of studies are essential for identifying/measuring tectonic activities, sediment diffusion, surface runoff in a drainage basin, and as an important tool for target oriented micro watershed management.  相似文献   

8.
The present paper deals with morphometric analysis of Koshalya-Jhajhara (K-J) watershed, tributaries of Ghaggar in northwestern India. The area forms a rugged topography having elevation range from 399 m to 1810 m MSL. Aster DEM and SOI toposheets have been used to calculate various parameters using Geographic Information System (GIS). Linear, areal and relief aspects for morphometric analysis were calculated using GIS. Total number of streams in the watershed are 991 out of which 543 are of 1st order, 259 are of 2nd order, 124 are of 3rd order, 58 are of 4th order and only 7 are of 5th order. The order of stream determines the chances of flood in the stream. Higher the stream order more the probabilities of flood. The present paper indicates that K-J watershed is of 5th order and less elongated in shape having lower peak flows of longer duration with dendritic pattern and having fine drainage texture. Bifurcation ratio varies from 3 to 5 which indicate that geological structures don’t have dominant influence on drainage pattern. High slope is witnessed in NE part and low slope in SW part with very low gradient ratio. Variables like stream frequency and drainage density determines the volume of the water discharge and its speed of flow in the river channels. Higher the stream frequency and drainage density more will be the probability of floods. These variables also effects temporal variations in the speed at which the water flows in the stream when flood reaches its peak.  相似文献   

9.
Geographical information system and remote sensing are proven to be an efficient tool for locating water harvesting structures by prioritization of mini-watersheds through morphometric analysis. In this study, the morphometric analysis and prioritization of ten mini-watersheds of Malesari watershed, situated in Bhavnagar district of Saurashtra region of Gujarat state, India, are studied. For prioritization of mini-watersheds, morphometric analysis is utilized by using the linear parameters such as bifurcation ratio, drainage density, stream frequency, texture ratio, and length of overland flow and shape parameters such as form factor, shape factor, elongation ratio, compactness constant, and circularity ratio. The different prioritization ranks are assigned after evaluation of the compound factor. Digital elevation model from Shuttle Radar Topography Mission, digitized contour, and other thematic layers like drainage order, drainage density, and geology are created and analyzed over ArcGIS 9.1 platform. Combining all thematic layers with soil and slope map, the best feasibility of positioning check dams in mini-watershed has been proposed, after validating the sites through the field surveys.  相似文献   

10.
Assessment of erosion status of a watershed is an essential prerequisite for integrated watershed management. It not only assists in chalking out suitable soil and water conservation measures to arrest erosion and conserve water but also helps in devising best management practices to enhance biomass production in watersheds. Keeping this in view, the present study has been undertaken by involving geospatial-statistical techniques to determine the critical and priority areas for soil and water conservation in Suketi watershed of the lower Himachal Himalayan region. A novel weighted sum analysis technique was used for ranking each of hydrological unit by obtaining the weightages from various morphometric parameters. This technique offers dynamic, effective and sustainable approach over traditional prioritization methods in which significance of each parameter were considered equally. Considering this approach, sub-watersheds were delineated into low, medium and high priority zones. The results illustrate that about 52 % of sub-watersheds of Suketi watershed are in moderate to high erosion and runoff susceptible zones. Therefore, these potential areas can be considered for preferential soil and water conservation planning. The results obtained from the study will be useful for various stakeholders such as agriculturists, water resource managers, conservation measures planners and decision policy makers for better management practices and decision making. The geospatial-statistical technique can be used for effective estimation of erosion status of watersheds leading to watershed prioritization for taking up soil and water conservation measures in watershed systems. Finally, this technique can be very useful in remote, rugged and inaccessible watersheds with absence of soil erosion and runoff monitoring.  相似文献   

11.
Morphometric analysis of a watershed of South India using SRTM data and GIS   总被引：3，自引：0，他引：3  
An attempt has been made to study drainage morphometry and its influence on hydrology of Wailapalli watershed, South India. For detailed study we used Shuttle Radar Topographic Mission (SRTM) data for preparing Digital Elevation Model (DEM), aspect grid and slope maps, Geographical information system (GIS) was used in evaluation of linear, areal and relief aspects of morphometric parameters. The study reveals that the elongated shape of the basin is mainly due to the guiding effect of thrusting and faulting. The lower order streams are mostly dominating the basin. The development of stream segments in the basin area is more or less affected by rainfall. The mean Rb of the entire basin is 3.89 which indicate that the drainage pattern is not much influenced by geological structures. Relief ratio indicates that the discharge capability of these watersheds is very high and the groundwater potential is meager. These studies are very useful for planning rainwater harvesting and watershed management.  相似文献   

12.
A geomorphic unit Usri drainage basin (latitude: 24° 04′00″ N to 24° 34′00″ N and longitude 86°05′00″E to 86°25′00″E) lies in north-eastern parts of Chhotanagpur Plateau, India, has been selected for morphometric analysis. Digital elevation model (DEM) has been generated by Cartosat stereo pair data at 10-m resolution. The morphometric parameters considered for the analysis includes the linear, areal, and relief aspects of the basin. Morphometric analysis of the river network and the basin revealed that the Usri Basin has sixth-order river network with a dendritic drainage pattern. The dendritic drainage pattern indicates that the basin has homogeneous lithology, gentle regional slope, and lack of structural control. The bifurcation ratio between different successive orders varies but the mean ratio is low that suggests the higher permeability and lesser structural control. The low drainage density, poor stream frequency, and moderately coarse drainage texture values of the basin indicate that the terrain has gentle slope, is made up of loose material, and hence has good permeability of sub-surface material and significant recharge of ground water. The shape parameters indicate that the basin is elongated in shape with low relief, high infiltration capacity, and less water flow for shorter duration in basin. The 50 % of the basin has altitude below 300 m and gently sloping towards the southeast direction. All the morphometric parameters and existing erosional landforms indicated mature to early old stage topography.  相似文献   

13.
Hydrogeological mapping and drainage analysis can form an important tool for groundwater development. Assessment of drainage and their relative parameters have been quantitatively carried out for the Morar River Basin, which has made positive scientific contribution for the local people of area for the sustainable water resource development and management. Geographical Information System has been used for the calculation and delineation of the morphometric characteristics of the basin. The dendritic type drainage network of the basin exhibits the homogeneity in texture and lack of structural control. The stream order ranges from first to sixth order. The drainage density in the area has been found to be low which indicates that the area possesses highly permeable soils and low relief. The bifurcation ratio varies from 2.00 to 5.50 and the elongation ratio (0.327) reveals that the basin belongs to the elongated shaped basin category. The results of this analysis would be useful in determining the effect of catchment characteristics such as size, shape, slope of the catchment and distribution of stream net work within the catchment.  相似文献   

14.
Sediment discharge due to soil and rock erosion within the watersheds is the major cause of siltation in water reservoirs. Siltation in reservoirs reduces the capacity for power production, irrigation water supply, and other domestic purposes. Hypsometric analysis has widely been used to identifying the geomorphic development stages (stabilized, equilibrium, and un-stable) to assess the erosion proneness of watersheds. In this study, watershed of Kurram Tangi Dam and its four sub-watersheds (SWs) were considered to determine their sediment discharge capacity through hypsometric analysis. The boundaries of watershed and sub-watersheds were delineated from Digital Elevation Model (DEM). The hypsometric parameters i.e., hypsometric integral (HI) and curves were generated using Geographic Information System (GIS) techniques. The HI values of SW-1 (0.41) and SW-2 (0.36) indicated that these two SWs were relatively more prone to erosion and contributed higher sediment discharge in Dam siltation. The results were validated through sampling the main drainage channel (Kurram River) to determine the sediment concentration at 12 sites during summer, winter, and spring seasons. Comparison of HI and sediment concentration of SWs presented high correlation (R2?=?0.87). The results emphasized the effective watershed management, extensive afforestation, and construction of silt-control structures at appropriate locations in sub-watersheds. This will ultimately maintain the water and power generation capacity as well as extending the life span of the Dam.  相似文献   

15.
A morphometric analysis was done to determine the drainage characteristics of Lules River basin using land-sat imageries and topographical maps. This catchment was divided into seven sub-basins for the analysis: Liquimayo, Hoyada, Ciénaga, De Las Tablas, Siambón, Potrerillo and San Javier. Yungas ecoregion covers almost all the watershed. The drainage patterns of the sub-basins are dendritic and parallel. The basin includes seventh order stream and lower streams order mostly dominate the basin. The development of stream segments is affected by slope and local relief. The mean bifurcation ratio indicates that the drainage pattern is not much influenced by geological structures. The shape parameters also reveal the elongation of the basin and sub-basins.  相似文献   

16.
Hypsometric analysis of watershed (area-elevation analysis) has generally been used to reveal the stages of geomorphic development (stabilized, mature and young). The geologic stages of development and proneness of the watersheds for erosion are quantified by hypsometric integral. The estimation of hypsometric integral is carried out from the graphical plot of the measured contour elevation and encompassed area by using empirical formulae. In this study, efforts were made to estimate the hypsometric integral values of Shakkar river watershed which is a tributary of Narmada river located in Madhya Pradesh. The watershed was delineated into eight sub-watersheds and hypsometric analysis was carried out for all of them using digital contour maps, which was generated using Arc/Info GIS. The hypsometric integral values for all the sub-watersheds of Shakkar river ranges between 0.47 and 0.51. In the study area, only mature stage of erosion cycle is identified.  相似文献   

17.
Watershed development and management plans are more important for harnessing surface water and groundwater resources in arid and semi-arid regions. To prepare a comprehensive watershed development plan, it becomes necessary to understand the topography, erosion status and drainage patterns of the region. This study was undertaken to determine the drainage characteristics of Pageru River basin using topographical maps on a scale of 1:50,000. The total area of the Pageru River basin is 480 km2. It was divided into X sub-basins for analysis. The drainage patterns of the basin are dendritic and include a sixth order stream. The quantitative analysis of various aspects of a river basin drainage network characteristics reveals complex morphometric attributes. The streams of lower orders mostly dominate the basin. The development of stream segments in the basin area is more or less affected by rainfall. The elongated shape of the basin is mainly due to the guiding effect of thrusting and faulting. The erosional processes of fluvial origin have been predominately influenced by the subsurface lithology of the basin.  相似文献   

18.
Remote Sensing and GIS techniques have been proved to be efficient tools in the delineation, updating and morphometric analysis of drainage basin. The present study incorporates a morphometric analysis of three sub-basins of Fatehabad area of Agra district using remote sensing and GIS techniques. The morphometric parameters of the sub-basins are classified under linear, areal and relief aspects. The drainage pattern exhibited by the main river Yamuna and its tributaries shows a dendritic pattern indicating homogenously underlain material while the mean bifurcation ratio values suggest that the geological structures are not disturbing the drainage pattern. The form factor value of sub-basins suggests that the main basin is more or less elongated. Circularity ratio values of the three sub-basins fall within range of elongated basin and low discharge. The area has low density indicating that the region has high permeable sub-soil material and dense vegetation. The values of drainage texture, drainage density and infiltration number indicate that sub-basin-III has the highest infiltration rate and low runoff, hence contributing most to the underground water resources. This study also indicates porous and permeable sub-soil condition in sub-basin-III. The values of sub-basin-I indicate low permeable subsoil material owning to high infiltration number value, hence low infiltration and high runoff.  相似文献   

19.
Jaggar watershed is a constituent of the Gambhir river basin, in eastern Rajasthan and covers an area of 352.82 km2, representing arid climate. The drainage network is dendritic to sub-dendritic pattern however parallel to sub-parallel has also developed locally. The Jaggar watershed has been divided into fourteen sub-watersheds, designated as SW1 to SW14, for prioritization purpose. The prioritization of the sub-watersheds has been done on the basis of morphometric analysis and land use/land cover categories. Various morphometric parameters (linear and shape) have been determined for each sub-watershed and assigned rank on the basis of value/relationship with erodibility so as to arrive at a compound value for final ranking of the sub-watersheds. Land use/land cover mapping has been carried out using IRS LISS III data of 1998. Based on morphometric and land use/land cover analysis and their ranks, the subwatersheds have been classified into four categories as very high, high, medium and low in terms of priority for conservation and management of natural resources. The prioritization results based on morphometry reveal that only SW7 and SW10 fall under very high priority, whereas SW6, SW11 and SW13 fall under very high priority on the basis of land use/land cover analysis. However on the integration of morphometry and land use/land cover only SW14 show common priority whereas rest have little or no correlation.  相似文献   

20.
Spatial pattern of geomorphometric parameters of two sub-watersheds in the Attapady valley, Kerala, is evaluated using the Geographical Information System. Both the aspatial and spatial morphometric and hypsometric measurements of the sub-watershed are compared. The analysis of geomorphometric parameters coupled with DEM and GIS suggests that the two sub-watersheds are structurally complex with high relief and the denuded hills are undergoing severe soil erosion. Terrain analysis enables evaluation of landform changes in the two sub-watersheds which indicate differences in the denudational history of adjoining watersheds. It is demonstrated that the domainal variations in the lithology and structural complexity are reflected in differences in the denudational history which in turn is manifested in the geomorphic parameters. The study also helps in developing functional relationships between geomorphometric parameters and hydrological variables.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号