RS & GIS

Abstract: The present study was carried out to decipher the groundwater potential zones in the coastal terrain of Tuticorin
using Indian remote sensing satellite IRS-1C, LlSS-III data on a 1:50,000 scale and Survey of India (SOI) toposheets.
The thematic layers such as lithology, slope, land-use, lineament, drainage, soil and rainfall were generated and integrated
to prepare the groundwater prospect and recharge map of the study area. These layers were transformed to raster data
using feature to raster converter tool in Arc GIS 9.2 software. Subjective weights are assigned to the respective thematic
layers and overlaid in GIS platform for the identification of potential groundwater zones within the area. These potential
zones were categorized as ‘high’, ‘moderate’, and ‘low’ zones with respect to the assigned weightage of different thematic
layers. The resultant map shows that 10% of the area has highest recharge potentials, this is due to the percolation of
precipitated water into the sub-surface rocks, followed by 65% of the area with moderate groundwater recharge potentiality,
and rest of the area has low recharge potential. The study highlights that the total average annual precipitated water
(877 mm) is responsible for natural recharge of the aquifers in the Tuticorin area.

Dust is an event that occurs in most sections of the world that leads to financial loss and harmful environmental impacts. Several factors are included in dust event incidence, some of them are natural and others are due to human processes and their impact on the environment. Thus, very critical situations are coming and it is expected that the majority of urban and rural populations will migrate to the rest of the country, especially from western and southwestern regions leading the way to a lot of economic damage. Studies conducted in the country showed that the western regions of the country are more exposed to dust systems due to their geographical and climatic location and the proximity to the deserts of neighboring countries such as Iraq, Syria and Saudi Arabia, especially since most of the atmospheric system of the North West, West and Southwest are imported into the country. For this purpose, investigating, studying and recognizing physical and chemical composition of dust and soil resulting from it to determine and identify harmful elements and ultimately policy-making and planning for its elimination as regional alliances in the field of policy-making and foreign cooperation vital. According to the obtained results, it was found that the dust in spring of 2015 in Zahedan city has spatial and temporal changes. The spatial and temporal changes in dust can be caused due to the low green space, especially in the direction of wind blowing, developmental activities and 120-day winds of Sistan and the difference in urban density and urban marginal topographic complications. According to zoning map in the spring of 2015, the existence of an inconsistency in the dust spatial variations in the spring indicated that spring is the source of dust in the city. Since part of this amount is due to the drying of Hamoon Lake, wind erosion control measures in these areas can be effective in reducing the loss of dust in the city of Zahedan. In Iran, the use of geographical information systems and remote sensing to monitor natural hazards is increasing. Hence, the attention of managers of various fields of natural resources and environment to the capabilities of this software and attention to the researches have done in this regard sound necessary and useful. The results of many studies in the country showed that the frequency of dusty days is increasing.