l l trig'ation,‘ place the inStruments near enough to
othat the water will be certain to reach them—.3
vprolgl 11-_lo¢atio_ns where one Wants-special knowledge of g
- soil’WaknThe'se locations may be difﬁcult to wet, may d1 '
Mutuura, Felix Gitonga Nthiga
Dedan Kimathi University of Technology, Nyeri, Kenya
School of Engineering
Department Civil Engineering
WATER BALANCE OF A CROPPED SOIL
BASIC SOIL- WATER RELATIONS
Soil can be regarded as a porous material in which solid, liquid, gaseous materials are present.
In mineral soil the solid material comprises 50-60% with organic matter content of less than
3%. The soil of an are
P LANT-WATER RELATIONS
Water in plants
Almost every active part of a plant contains water, often some 80-90% of the total fresh
weight. Water in the plant mostly is present in the liquid phase, although some water
vapour is present in the intercellu
Irrigation is the artificial application of water to arid areas for growing crops.
NEED FOR IRRIGATION
1) Deficient amount of rainfall- less than 100cm
2) Non uniformity of rainfall- Applies where there is sufficient rainfall but not uniformly
The methods for calculating evapotranspiration from meteorological data require various
climatological and physical parameters. Some of the data are measured directly in weather
stations. Other parameters are
Introduction to crop
This chapter outlines the crop coefficient approach for calculating the crop evapotranspiration
under standard conditions (ETc). The standard conditions refer to crops grown in large
CROP WATER REQUIREMENTS
Knowledge of water use by crops in addition to the water retention of the soils is
fundamental in the design and operation of irrigation systems. The pattern of crop water
use, allowing for rainfall, operation lo
Determination of ETo
This chapter demonstrates how the crop reference evapotranspiration (ETo) is determined either
from meteorological data or from pan evaporation.
The FAO Penman-Monteith method is maintained as the sole stand
REVIEW OF IRRIGATION METHODS
Irrigation of agricultural lands is the main consumer of water for human use.
Irrigation significantly increases agricultural yields and farmers incomes, particularly
in arid and semi arid lands (ASAL).
FAO Penman-Monteith equation
This chapter introduces the user to the need to standardize one method to compute reference
evapotranspiration (ETo) from meteorological data. The FAO Penman-Monteith method is
recommended as the sol
The Matrix Stiness Method for 2D Trusses
CEE 421L. Matrix Structural Analysis
Department of Civil and Environmental Engineering
Henri P. Gavin
1. Number all of the nodes and all of the elements.
2. Identify the Displaceme