**1.2. Importance of irrigation**

Irrigation is undertaken to provide insurance against droughts, cooling of the soil and atmosphere and provide more favorable environment for plant growth. It can also wash out or dilute salts in the soil, reduce the hazards of piping, and soften tillage pans [8]. Generally, the goal is to supply the entire field uniformly with water, so that each plant has the amount of water it needs. In arid and semi-arid areas where there are less rainfall, irrigation is often used to grow cash crops, develop landscapes and vegetate disturbed soils. This is expected of the increase in world population and the need to expand agricultural land under the threat of climate change. It has contributed immensely in the production of food in industries.

### **1.3. Impact of irrigation on vegetation and soil**

from increased level of soil salinity and rise in water table. Soil salinity affects soil chemical, physical, and biological characteristics of the soil, fertility, and sustainable productivity unless it is properly monitored. Geo-informatics involves a combination of special techniques, technologies and tools for the acquisition, processing, management, analysis, and presentation of geospatial data [2]. It is a combined method to GIS and remote sensing. Remote sensing and GIS are well established information tools, since they give reasonable pictures of the entire process in spatial and temporal terms. They both provide a cost effective and adequate understanding of landscape dynamics, detect, identify, map, and monitor differences in land use and land cover pattern over long period of time [3]. The application of Satellite Remote Sensing (SRS) and GIS has been proved useful and successful in many fields such as natural resources management, agriculture, and environmental issues and water resources. Remote sensing approaches are very effective for detecting, monitoring and control of soil salinity. Remotely sensed data are used to assess soil salinity either on bare soils with salt crust or

through biophysical properties of vegetation as these are affected by salinity [4].

Replace environmental land degradation has recently become a global, urgent issue, and is now being considered with high priority, especially in the developing countries in order to meet the food and fiber demands of accelerated population pressure with limited available resources. One of the goals of irrigation is to boost food production in a sustainable technique so that a fast growing global population could be fed. Sustainable irrigation scheme can only be achieved effectively by taking into consideration the environmental effectiveness and availability of funds to maintain the implemented project. The function of irrigation is to apply water to maintain crop evapotranspiration, the total amount of available water essential for economy, health, and welfare of a very large part of the world [5]. Analyses of information from Asia have also shown that yields per area, for most crops have increased between 100 and 400% because of irrigation [6]. Based on the management system of irrigation scheme, it can provide both positive as well as negative effects on vegetation cover. Well-planned irrigation scheme have good natural vegetation conservation and management plans. Several factors could influence the salinity levels of irrigated land. One of the factors is the irrigation

Irrigation is undertaken to provide insurance against droughts, cooling of the soil and atmosphere and provide more favorable environment for plant growth. It can also wash out or dilute salts in the soil, reduce the hazards of piping, and soften tillage pans [8]. Generally, the goal is to supply the entire field uniformly with water, so that each plant has the amount of water it needs. In arid and semi-arid areas where there are less rainfall, irrigation is often used to grow cash crops, develop landscapes and vegetate disturbed soils. This is expected of the increase in world population and the need to expand agricultural land under the threat of

climate change. It has contributed immensely in the production of food in industries.

**1.1. General background**

66 Multi-purposeful Application of Geospatial Data

method [7].

**1.2. Importance of irrigation**

The practice of irrigation sometimes has an adverse effect on environmental condition otherwise properly monitored, planned and managed. Past record claims that human activities have a strong effect on the natural environment and becoming the main cause of environmental degradation [9]. The expansion of irrigation project has many advantages. However, largescale irrigation projects changes natural ecosystem. To undertake large irrigation projects, vegetation cover needs to be cleared and different construction activities needs to be done. Natural vegetation is an eminent parts of the ecosystem negatively affected with large-scale irrigation projects [10]. Soil being a vital natural resources, it has been assisting the increasing number of life on earth. As regards to increase in population, food demand also increased. This in turn put-size pressure on land/soil resource, areas of land that are formerly considered as marginal are now being cultivated [11].
