Chapter – 1
INTRODUCTION
During the initial time of human civilization, different ways of irrigation were used. Well known oldest civilizations were focused on the area of irrigation. Present approach towards this topic is highly precise and qualitative.
1.1 water scarcity
The population growth and industrilisation lead to exponential growth intheper head consumption of water. At the same time unethiticic exploition of natural resources caused soil erosion and related problems, like lack of ground water changing the condamination of ground water etc. now we are facing serious water scarcity problems.
For ground water recharging natural method is best suited. Natural method mainly focus on plantation.
1.2 Water some facts & figures…show more content… Time may be expressed in hour or day or month. This is the quality of water lost from the crop suface in unit depth of water. In one hector surface area 10,000 m2 have water depth 1mm is equal to loss of water volume of 10m3. [2]
2.2.5 Factors effecting Evapo transpiration
Climate condition, type of crop and other environmental factors effect the evapo transpiration.
2.2.6 Weather parameters
Climate condition are ration, temperature, humidity and wind speed from figure 2.5 represents reference crop transpiration. It means the evapo transpiration from standard crop surface. [2]
2.2.7 crop factors crop type depend on the crop height, with stand capacity of transpiration, roots of crop and cover ground leaves which effects different type evapo transpiration levels.
2.2.8 Management & environmental conditions
Soil condition likes fertility and salidity, water logging etc will effect the evapo transpiration. Irrigation method, cultivation method, climate and crop factors also effective evapo transpiration. Wind velocity also effect. Transpiration rate will reduce the anti transparent radiation shield material covering to…show more content… It is calculated from weather data. The FAO Penman Monteith method in considered as standard method of evapo transpiration measurement. [2]
2.2.11 Evapo transpiration measurement from Pan evaporation
Vap[orisation from open pan water surface is the combined effect of radiation, temperature, humidity and wind speed. Water lost by evoportion from open pan water surface index of evapo transporation . [2]
2.2.12 Pen man – Monteith equations
In 1948, Penman derived an eqation of from energy and mass balance are considering the weather factors of temperature, humidity, wind velocity and solar radiation.
2.3 Evaportion Pan
The evaporation pan of standard class A typed consists of 54mm height and 1206mm dimeter. It is supported usually on wooden base mounted on leveled surface. It is kept on open surface without the obstacts of trees. It is measured an accuracy of 0.02mm. The amount of vaporization is the combined effect of temperature, humidity, wind speed and sunshine.[3] The temperature condition of minimum and maximum recorded with evaporation. For measuring wind speed sensor also fitted. From all sensors measured the data and processed on evaporation pan software.