1st lecture, week-1 intoduction to irrigation and drainage and basic concept

8/12/2019 1st Lecture, Week-1 Intoduction to Irrigation and Drainage and Basic Concept

1/17


2/17

() () () (The Noble Quran, 21:30)


3/17


4/17

Course Title: Irrigation and Drainage Practices

Course No.: ID-102Credit hrs.: 2(1-1)

Sikandar Ali

Lecturer,

Department of Irrigation and drainage,

University of Agriculture, Faisalabad.


5/17

ContentsTheory

Irrigation Water Resources: Irrigation, importance of irrigation, sources of irrigation

water, Indus Basin Irrigation System, components of irrigation system, irrigation

system management, warabandi, hill torrents.

Measurement of Irrigation Waters: Importance, units, methods.

Irrigation Methods: Surface, subsurface, sprinkler, drip, selection of irrigation

method.

Irrigation Scheduling: Components, soil water plant relationship, water requirements

of crops, efficiencies.

Irrigation Pumping Systems: Definition, types of pumps -Reciprocating, centrifugal,deep well turbine, jet pump-Power requirements for pumping, efficiency, pump

characteristics, tubewell components

Drainage of Agricultural Lands: Concept, type and purpose of drainage, sources of

excess water, classification of drainage systems.


6/17

Contents

Practical

Flow measurement by velocity area method.

Flow measurement by Volumetric method

Flow measurement by weighing method

Flow measurement by Current meter method

Flow measurement using a weir.

Flow measurement using a cutthroat Flume.

Field exercise on soil moisture determination.

Practical exercises on irrigation scheduling.

Practical exercises on pumping systems


7/17

Basic Terminologies and Concepts

Irrigation

Artificial application of water to the soil through manually or mechanically

managed system for the purpose to

Supply moisture essential for plant growth

Encourage plant root development

Cool the soil and atmosphere

Create favorable condition for plant growth

Transport nutrients from soil to plant


8/17

Necessity of Irrigation

In areas with unreliable rainfall, watering of crops is essential.Irrigation is necessary where rainfall amount is not sufficient to meet

crop water requirement.

In Pakistan

Average Annual Rainfall 10-14 inch

Potential demand of water for Agriculture is about 70 inch


9/17

Drainage

Drainage is the natural or artificial removal of surface and

subsurface water from an area.

An agricultural drainage system is a system by which the waterlevel on or in the soil is controlled to enhance agricultural crop

production.


10/17

Precipitation

In meteorology,precipitation is any product of the condensation

of atmospheric water vapour that falls under gravity.

Generally, any form of moisture received on earth is called as

precipitation.

It includes,

Rain (liquid form of precipitation)

Snow (Crystalline water ice form)

Hail (Irregular lumps of ice called hailstone)

Sleet (Rain and partially melted Snow)


11/17

Arial distribution of rainfall zones in Pakistan

Sr. No. Rainfall Zone Percent area Average annual

rainfall

1 Arid 67 30 inch


12/17

Rainfall and Effective Rainfall in Agriculture

Total amount of water received on earth from atmosphere is called

as rainfall.

Effective rainfall is that portion of rainfall which is utilizable by

crop.

Losses may be due to evapotranspiration, infiltration and surface

runoff.

ER=TR-losses


13/17

Infiltration

Entrance of water into the soil surface from

atmosphere is called as infiltration

Percolation

Movement of water through porous medium

due to gravity and capillary forces.

When water after infiltration seeps down

called as percolation.

Deep percolation

Downward movement of infiltrated water

below the root zone and mixing in the

groundwater


14/17

Evapotranspiration (ET)

Evaporation

Loss of water from soil surface to

the atmosphere is called as evaporation

TranspirationLoss of water from plant surface to

atmosphere is called as transpiration.

Evapotranspiration

Combine loss of water from soiland plant surface to atmosphere is called as

evapotranspiration.


15/17

Consumptive Use (CU) and ET

CU= Et + water used by plant in

1. Metabolic process

2. Structural growth of the plant

3. Tissue building process of the plant


16/17


17/17

GCA and CCA of Pakistan

Total Area = 196 million acre (ma)

Cultivated area= 26% of Total Area

196 ma * 0.26 = 51.8 ma or 21 mha ( million hactare)

Irrigated area = 77 % of Cultivated area

Irrigated area = 0.77 * 51.8 ma = 40 ma OR 16.2 mha

1st lecture, week-1 intoduction to irrigation and drainage and basic concept

Documents