The Impacts on Agriculture
Production from Irrigating with Saline
Water and Ways to Efficiently
Manage the Impacts
By: Kimberly McLeod
GEO 361
Objectives
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•
•
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Understand salinity’s impact on agriculture lands
Understand the impacts of saline on crops
Determine how much saline is toxic to crops
Find solutions for farmers to deal with salinity
Introduction about the impact
Earth’s water budget:
Reservoirs
Glaciers (F)
Rivers (F)
Oceans
Groundwater (F)
Lakes (F)
Atmosphere
Earth's P ercent Water Budget
1.76 %
0.00015 %
96.5%
1.7%
0.013%
0.0009%
Residence Time
11,990yrs
0.05 yrs
2,652 yrs
19,677yrs
34.58 yrs
0.026 yrs
• Food production will need to increase by 38% by
2025
• Stress to farmers to secure good irrigation water for
their crops.
BUT some farmers have to use saline water because
there are limited supplies of good quality of water or
use shallow ground water that has high amounts of
What is salinization?
A complex process: movement between salts (primarily
NaCl) and water in the soil during seasonal cycles and its
interactions with groundwater.
– Sources of the salt: rainfall, aeolian deposits, mineral
weathering, and stored salts
– According to the USGS- there are 3 categories for
saline water
• Slightly saline: 1,000 to 3,000 ppm
• Moderately saline: 3,000 ppm to 10,000 ppm
• Highly saline: 10,000 to 35,000 ppm (ie Seawater =
35,000 ppm)
How saline water reaches the crops:
In general:
• In 2003, it was reported that 15% of total land area of
the world has been degraded by soil erosion, physical
and chemical degradation (including soil salinization)
• More than 100 countries are affected by salinity
Results for irrigated lands:
• Estimated that 20% of irrigated lands in the world are
affects by salinity
• Every year 0.2%-0.4% of total irrigated land is being
retired because of high amount of salt.
• Losing money: US spend $12 billon per year on impacts
of salinity related to agriculture.
Impact of saline water on crops
Each plant needs to be addressed separately.
Two large groups: Halophytes (ie Date Palms) and
Glycophytes (ie Faba beans, Tomatoes)
Generally, when a plant comes in contact with saline
water there are physiological changes in the cell between
the water and ionic status.
–High amounts of Na+ and Cl- causes an imbalance.
Results in reduction of K+, Ca2+, Mn2+
–This mineral reduction impacts the plant’s growth
from germination to harvest
Halophytes: Date Palms
Found in the Middle East and California because they can
withstand long, dry summers and mild winters
Journal by Alhammadi et al:
• 8,000 ppm - 20,000 ppm of
NaCl = no affects on growth
• 20,000 ppm + various salts =
drastic decrease on growth
• Decrease in K+, Mg2+, Ca2+
• Conclusion: Don’t grow date
palms with more than 20,000
ppm of NaCl
Glycophyte: Faba Beans
In the legume family that is native to North
Africa.
Experiment by El Fouly et al:
1. Control- No NaCl
3. 1,000 ppm NaCl -reduction in
growth
Decrease in ability to take up water
and injury to cells in leaves
Conclusion: With 1,000 ppm NaCl
inhibits the growth of the crop. Do not
use more than 1,000 ppm of NaCl.
So what can be done to
increase the growth of the
crops when farmers have to
use saline water?
Solution: Micronutrient Foliar Spray
Made of: Fe, Mn, Zn
1. Control
2. Control + Micro
3. 1,000 ppm NaCl
4. 1,000 ppm + Micro
Solution: Better Irrigation Techniques
Bad: Furrow
Good: Drip
To conclude:
• Earth has a shortage of fresh water to meet everyone’s
needs
• Farmers are under pressure to produce more food but
some are forced to use saline water
• Salinity affects every climatic zone but primarily arid and
semi-arid climates because of high evapotranspiration
rates
• Using saline water has detrimental effects on land such
as retirement and the decrease in crop yields
• How much salt in the water determines if the plant
survives or dies
• Two solutions include Micronutrient Foliar Spray and
better irrigation techniques
Questions?