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Satellite Remote Sensing Technologies for Water Studies, Assir Province;Saudi ArabiaDr. AlOtaibi Eed LafiAssistant Professor of Remote Sensing & Geographical Information Systems, School of Human Sciences, Geography Dept., King Khalid University, POB 1183, Greiger compound Abha, Saudi Arabia.firstname.lastname@example.org
SummarySatellite Remote Sensing Technologies (SRSTs) for monitoring inland water bodies have been under development since 1980's. The tools used to develop these techniques have ranged from an empirically to semi-empirical techniques and analytical methods for producing quantitative water quality maps (Dekker 1997, AlOtaibi and Zaki 2008;2009). Several investigators (e.g., Dekker 1993, Gitelson, et al. 1993, Jupp et al. 1994a, Jupp et al. 1994b) have developed empirical regression formulas for the prediction of water quality parameters from spectrometer data by employing spectral ratios, typically reflectance ratios, as the independent variables. The predicted water quality parameters have included chlorophyll concentrations, suspended matter concentrations and turbidity.
Developing an approach for optimum planning and management would be helpful at harvesting water natural resources for sustainable development including flooding hazards prevention and better living.Many countries complain of water related problems and they expect the worst because of the increases of the population, urban and agricultural projects especially, fragile regions which had begun complaining of pollution problems (AlOtaibi, 2008). It is estimated that the U.S.A spends about $70 billion annually on environmental regulatory programs (Whittier and Paulsen, 1992). In particular, the quality and condition of the country’s water resources have become a prime concern over the past decades (Carpenter et al., 1998; Loague,1998). Despite of that about 80% of stream miles go unassisted with respect to the requirements for Section 305(b) of the U.S Clean Water Act (GAO, 2000).
During the last two decades Satellite Remote Sensing Technology (SRST) of earth resource satellite systems has been implemented effectively : • to understand the concepts, to monitor and map the changes of the earth resources because of the characteristics of satellite sensors; higher temporal, coverage, spectrum and spatial resolutions. Since1990s SRST imageries reflect an integration of physical and biological processes occurring in the catchment areas. This paper proposed for an approach of mapping permanent Inland water bodies and water landscape within Assir Province Saudi Arabia using SRSTs (Fig., 1). With the increasing feasibility of using SRSD, Landscape-water quality studies can now be more easily performed even at regional, multi-governorate scales water mapping in a very cost efficient way.
Traditional method of relating landuse and landcover (LULC) to water quality has been extended to include landscape patterns and other landscape vital information derived from SRSD. Three items were in focus: 1) the increasing recognition of the importance of larger-scale studies of regional water bodies mapping and quality investigations that require a landscape perspective; 2) the increasing importance of SRSD, such as of the imagery derived normalized difference vegetation index (NDVI) and vegetation phonological metrics derived from time series NDVI data; and 3) landscape pattern metrics -which explained some of the variation in water quality not explained by LULC. However, in some other studies, the NDVI metrics were even more highly correlated to certain quality parameters than either landscape pattern metrics or LULC proportions.
Recent works SRSThave demonstrated the potential: usefulness in monitoring watershed conditions across large regions. Optical indicators of water quality have the potential of enhancing the abilities of resource managers to monitor permanent water bodies. However, the degree to which optical indicators are useful may depend on their applicability to : data collected from multiple water bodies.
The water resources of Assir region -with an area of about 85000 km2 south-west S.A where the widespread climate is arid to semi-arid –maybe described as very scarce and fragile. Therefore, The proper mapping, assessment, planning and development of water resources are key elements in the overall development of the region, therefore, improper management and planning either because of lack of data or because of inadequate studies, has often resulted in quality deterioration and water supply problems under the intensive urban development and limitation and deterioration of water resources (AlOtaibi, 2008, 2009).
The researcher studies showed that: SRSTs would be the most efficient way to map and diagnose the condition of water resources under such an environment especially when assessing water quality when field measurements maybe time consuming, costly, and limited logistically. Moreover, because of the increase-ness in water quality parameters importance such as chlorophyll a, turbidity, total suspended solids (TSS), and nutrients as symptomatic of“eutrophic” conditions, it would be advantageous to be able to detect “eutrophic” conditions using multiple water sites without relying on field measurements only.
SRST would overcome water studies constraints by providing an alternative means of water quality monitoring (Shafique et al. 2001; AlOtaibi. 2009). SRST can also be helpful in measuring the properties of objects by: calculating the amount of radiation they absorb, emit, or reflect at various wavelengths along the electromagnetic spectrum. Optical water quality research has a broad scope for developing environmental indicators that are useful in assessing, quantifying and monitoring water quality. More fundamentally, the absorption and scatteringoflightby components provide basic information from which relationships with other water quality indicators such as water clarity readings can be derived (Jupp et al. 1994a, Dekker 1997). Although a such fairly new method, thedevelopment of spectral indices can now be even a useful and easy tool for the diagnosis of “eutrophic” conditions.
According to previous investigationsunlike SPOT-XS, the Landsat imagery tended to mask most anthropogenic disturbances and vegetation differences, leaving largely topographic information when used the following combination of bands e.g 5,7,4 and 7,4,3. It has shown that Landsat image can make a significant contribution in rock-type discrimination over other satellite imageries of the following generation such as SPOT-XS and IKONOS data when talking regional hydrological exploration. Previous studies (KACST, 1997,1998, 2001) of lineaments, particularly those aligned over significant distances with the main geo-morphologic trends in other basaltic terrains of the region, may likewise lead to sites of groundwater of different reservoirs….
SRSTs are presently being used as a good and objective sampling frame for solving problems like contamination of surface and ground resources changes in water ecological parameter and many more (AlOtaibi, 2003; 2009). SRSTs were used in this study primarily to: • map and delineate the boundaries of different water features mainly, the permanent water bodies of Assir Province S.A. However, extracting details from these satellite imagery has depended on the spectral contrast between the water objects and their surroundings. Landsat TM, TM+ imageries were used to extract drainage digital maps at a proper scale (e.g.,≤ 1:50000), showing the major water bodies of the region. Other major features such as "lineaments" were all clearly displayed visually on the Landsat-TM imagery as straight to curvilinear topographic breaks. It was found also that terrain elements were more readily distinguished on Landsat TM, TM+, and SPOT-XS data, although, almost all the same features could be detected on both types of satellite imageries of Assir Province SA.
Fig. 1: Digital mapping sequences of permanent water bodies of Assir Province S.A :mapping sources 1) digital map of Assir Province ( AlOtaibi & Quine 2007) (permanent water bodies map) 2) full digital Landsat TM sat-scenes of Assir Province-03≥ 3) full digital Landsat TM sat-scenes of Assir Province-08≥ ( (permanent water mapping :water bodies by governorate fieldwork verifications & samplings (data base building)
The major Role of Satellite Remote Sensing Technique used for this research was: easing water map updating of Assir Region The operation consists of both: • the delineation of boundries and • the determination of surfaces of individual features, such as permanent water bodies. The sequence of operations is basic: Image enhancement geometric correction, Visual interpretation, digitizing...
To access previous published papers of this study: • Al-Otaibi, E L: Quality of water sources: bacteriological assessment in Khamis Mushait, southwestern Saudi Arabia. Water resources Applications(International Journal of Health Geographics 2009, 8:16 (IJHG:21 March 2009)) : http://www.ij-healthgeographics.com/content/8/1/16 • Al-Otaibi, E L and Zaki, M.S.A: Physico-chemical quality of drinking water sources at Khamis Mushait, Assir, south-western Saudi Arabia( African Journal of Clinical and Experimental Microbiology ,Vol. 10 (2) 2009: pp. 117-127): http://ajol.info/index.php/ajcem/issue/view/945 • Al-Otaibi, E L and Zaki, M.S.A: Quality Assessment of traditional water resources in Khamis Mushait City, Abha Metropolitan, Assir Province, Saudi Arabia (accepted full paper atMagazine of the Center of Geographic & Cartographic Research, Menufia University, Issue 1, 2009, Egypt). • ب - بحوث مقدمة في مؤتمرات علمية متخصصة ومحكمة ومنشورة بأكملها في مداولات المؤتمر (كتاب المؤتمر) :- • Al-Otaibi, EL and Quine T : Satellite Remote Sensing & Geographical Information Systems for Archaeological Heritage Applications Assir Project, Saudi Arabia. (The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, 2005 .. http://www.isprs.org/commission8/workshop_urban/al-otaibi.pdf