msu-ceco/aec_v1 · Datasets at Hugging Face

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One instrument area and the hydrostat area received similar amounts of water, although less than the average for the area as a whole.
Water application at the hydrostat and instrument areas was thus measured eleven times directly, and the ratio of application depth to meter reading was obtained.
The average ratio was then used to convert the monthly water use, as read on the meter, to the depth of
water applied at the hydrostat and instrument areas.
Early morning timing reduced the effects of wind on the sprinkler distribution pattern to a minimum.
The table shows monthly irrigation applications for a full year.
It also includes rainfall and air temperature records from the Citrus Research Center Weather Station located about one mile away.
Correcting the total metered values to the amounts of water applied at the instrument area, and adding the rainfall, gives a reasonable approximation of the monthly evapotranspiration for turf.
Tensiometers with cups located at 11/2-, 3-, 6-, 12-, and 20-inch depths were read daily between 4 and 5 p.m.
The readings indicated that the major amount of root activity was in the upper 4 inches of soil.
Readings from the two shallower depths showed wide variations.
Usually these instruments would read 10 to 15 centibars on the day following an irrigation and would read values above 50 on the evening before an irrigation.
During August, there were occasional days when suction values at these depths exceeded the range measurable with tensiometers.
Since only 0.35 inch of water was applied at the instrument area per irrigation, very little day-to-day change in the readings occurred at the 12and 20-inch depths.
However, starting in July and continuing through August, values at the 12-inch depth slowly increased from 7 to about 40 centibars.
With more moderate weather conditions in September, readings at the 12-inch depth gradually decreased.
By the end of November, values at this depth were similar to those during the first six months of the year.
Some adjustment in monthly evapotranspiration values might be justified because of water storage changes in the soil profile, but the amounts added to the
MONTHLY IRRIGATION APPLICATIONS AND VALUES CORRECTED FOR NONUNIFORM DISTRIBUTION OF WATER BY SPRINKLERS, INCLUDING RAINFALL AND AIR TEMPERATURE DATA FROM THE CITRUS RESEARCH CENTER WEATHER STATION
Depth ot water from
1962 hydrostat Without meter readings, inches hydrostat With Depth of water on instrument areo, inches Rainfall, inches Evapotrans- piration, inches temperature monthly air Mean F Evaporation, inches
January 2.14 2.17 1.4 1.9 3.3 53
February 0.57 0.4 3.7 4.1* 51
March 0.78 2.71 1.8 0.8 2.6 51
April 8.64 7.76 5.2 5.2 64
May 9.34 7.45 5.0 0.3 5.3 62
June 9.16 7.35 4.9 4.9 68
July 11.35 8.61 5.7 5.7 74
August 11.96 8.36 5.5 5.5 77 8.51
September 11.63 5.90 3.9 3.9 73 6.5
October 4.52 4.03 2.7 2.7 64 4.3
November 4.78 3.01 2.0 2.0 60 2.7
December 3.71 2.63 1.7 1.7 54 2.4
Total 78.01 60.55 40.2 6.7 46.9
Rainfall probably exceeded evapotranspiration for February.
Estimated from measurements for only half of August.
July and August periods would in turn need to be subtracted from the September and October values.
The total change of water stored in the 4to 16-inch layer of soil, based on laboratory data, was estimated to be about 1/2 inch.
While flow velocity of water through the profile cannot be measured explicitly, some indication of its direction was obtained by evaluating the hydraulic gradient tending to cause flow.
Values of the hydraulic gradient between the 12and 20-inch depths were such that downward flow occurred from January through June.
Monthly means of daily values varied from 0.5 to 0.05.
Values for July indicated flow was upward and the monthly mean hydraulic gradient was 21 for the month of August.
Values indicating upward flow were 8 for September, 2 for October, and 1 for November.
During December, the hydraulic gradient showed downward flow.
Conductivity values for the decomposed granitic subsoil, estimated from laboratory measurements, indicated that total flow, between the 12and 20-inch depths for any one month, probably did not exceed 0.1 inch.
Again no attempt was made to correct the amounts of applied water for this transfer in the soil profile.
A 14-inch diameter insulated evaporation pan was installed in August with the water elevation about level with the turf.
Evaporation values for the last four months of the year are included in the table.
All of the measurements indicated were made while the irrigation program was completely under automatic control.
The automatic controller called for irrigation over 100 times during the year.
This frequent irrigation with relatively low volume applications per irrigation appears to be well adapted for making evapotranspiration measurements.
With relatively few additional modifications, this approach could be used to measure evapotranspiration for the wide range of conditions under which turf is being grown.
S.
J.
Richards is Soil Physicist and L.
V.
Weeks, Laboratory Technician, Department of Soils and Plant Nutrition, University of California, Riverside.
Funds for purchasing irrigation equipment were provided by the Water Resources Center, University of California, Los Angeles.
Moist O'Matic, Incorporated, Riverside, California, contributed to the installation of the automatic sprinkler system.
The kickoff event is always one of mixed emotions for attendees, as you have the new participants that are entering with eager anticipation to get started, but also the past competitors that are attending to learn what has changed, as well as continue to network and build the peer-to-peer relationships that TAPS prides itself on, said TAPS Program Manager Krystle Rhoades.
Selection and Management of Efficient Hand-move Solid Set and Permanent Irrigation System
Prepared by: Robert Evans, Extension Agricultural Engineering Specialist R.E.
Sneed, Extension Agricultural Engineering Specialist
Published by: North Carolina Cooperative Extension Service Publication Number: EBAE-91-152 Last Electronic Revision: June 1996
Rainfall is the principle source of water for North Carolina crops.
However, many farmers are turning to irrigation to supplement precipitation.
There are many types of irrigation systems.
But, most farmers have limited choices for their particular farm or field.
Some systems are inherently more water and energy efficient while others are designed to overcome limitations such as irregular field shapes, sloping land, or limited water supplies.
All of these factors should be considered before selecting a particular type of system.
Hand-move systems are normally used to irrigate small fields.
Solid-set and permanent sprinkler irrigation systems are used for irrigation, frost/freeze protection, evaporative cooling, and land application of nutrient-rich effluent.
Selection and management considerations for hand-move solidset and permanent sprinkler irrigation systems are discussed in this article.
Selection and management criteria for other types of irrigation systems are presented in articles EBAE 91-150: Self-Propelled Gun Traveler Irrigation Systems, EBAE 91-151: Center Pivot and Linear Move Irrigation Systems, and EBAE 91153: Low Volume Irrigation Systems.
Sprinkler irrigation systems have been available for more than 70 years.
The early systems used lightweight steel pipe and nonrotating sprinklers.
Rotary impact sprinklers were introduced in the late thirties.
However, it was not until after World War II, when aluminum pipe became available, that portable hand-move system became practical.
Most of the early rotary impact sprinklers were low capacity, medium pressure, and constructed of brass.
Some companies supplied gun sprinklers, but early models were not very satisfactory, because of the high application rate and potential for runoff.
Over the years, the trend has been toward larger sprinklers.
Several companies now supply a low capacity gun sprinkler which has reduced some of the runoff problems typically associated with gun type sprinklers.
Sprinklers are now available with plastic, brass, aluminum, and some stainless steel components.
Improvements in bearings contribute to longer life and less maintenance.
Quality control has also improved.
The major change in aluminum pipe has been a trend toward thinner wall aluminum pipe and stronger alloys.
Couplers and gaskets have been improved to reduce leaks at joints.
The number of coupler manufacturers has been reduced.
Most of these changes have occurred because of the introduction of other types of irrigation systems such as self-propelled gun travelers, center pivots, linear move, low volume, and sub-irrigation.
Sprinkler spacing's for portable irrigation systems range from 40 feet by 40 feet for small sprinklers to greater than 200 feet by 200 feet for gun sprinklers.
Spacing's may be square, rectangular, or triangular.
Spacing's are usually about 60 percent of sprinkler wetted diameter, but may need to be adjusted for wind conditions.
Singleor double-nozzle sprinklers may be used.
The doublenozzle sprinkler generally provides better uniformity, because the second nozzle provides water close to the sprinkler.
Smaller sprinklers, because they are less affected by wind, provide better uniformity than gun sprinklers.
However, the labor required for moving pipe when smaller sprinklers are used is increased considerably.
Figure 1 shows a typical layout of a portable hand-move aluminum pipe system.
Two laterals are operated at one time.
Spacing between sprinklers is 60 feet and spacing between laterals is 60 feet.
The first and last sprinklers on each lateral are 30 feet from the edge of the field.

One instrument area and the hydrostat area received similar amounts of water, although less than the average for the area as a whole.

Water application at the hydrostat and instrument areas was thus measured eleven times directly, and the ratio of application depth to meter reading was obtained.

The average ratio was then used to convert the monthly water use, as read on the meter, to the depth of

water applied at the hydrostat and instrument areas.

Early morning timing reduced the effects of wind on the sprinkler distribution pattern to a minimum.

The table shows monthly irrigation applications for a full year.

It also includes rainfall and air temperature records from the Citrus Research Center Weather Station located about one mile away.

Correcting the total metered values to the amounts of water applied at the instrument area, and adding the rainfall, gives a reasonable approximation of the monthly evapotranspiration for turf.

Tensiometers with cups located at 11/2-, 3-, 6-, 12-, and 20-inch depths were read daily between 4 and 5 p.m.

The readings indicated that the major amount of root activity was in the upper 4 inches of soil.

Readings from the two shallower depths showed wide variations.

Usually these instruments would read 10 to 15 centibars on the day following an irrigation and would read values above 50 on the evening before an irrigation.

During August, there were occasional days when suction values at these depths exceeded the range measurable with tensiometers.

Since only 0.35 inch of water was applied at the instrument area per irrigation, very little day-to-day change in the readings occurred at the 12and 20-inch depths.

However, starting in July and continuing through August, values at the 12-inch depth slowly increased from 7 to about 40 centibars.

With more moderate weather conditions in September, readings at the 12-inch depth gradually decreased.

By the end of November, values at this depth were similar to those during the first six months of the year.

Some adjustment in monthly evapotranspiration values might be justified because of water storage changes in the soil profile, but the amounts added to the

MONTHLY IRRIGATION APPLICATIONS AND VALUES CORRECTED FOR NONUNIFORM DISTRIBUTION OF WATER BY SPRINKLERS, INCLUDING RAINFALL AND AIR TEMPERATURE DATA FROM THE CITRUS RESEARCH CENTER WEATHER STATION

Depth ot water from

1962 hydrostat Without meter readings, inches hydrostat With Depth of water on instrument areo, inches Rainfall, inches Evapotrans- piration, inches temperature monthly air Mean F Evaporation, inches

January 2.14 2.17 1.4 1.9 3.3 53

February 0.57 0.4 3.7 4.1* 51

March 0.78 2.71 1.8 0.8 2.6 51

April 8.64 7.76 5.2 5.2 64

May 9.34 7.45 5.0 0.3 5.3 62

June 9.16 7.35 4.9 4.9 68

July 11.35 8.61 5.7 5.7 74

August 11.96 8.36 5.5 5.5 77 8.51

September 11.63 5.90 3.9 3.9 73 6.5

October 4.52 4.03 2.7 2.7 64 4.3

November 4.78 3.01 2.0 2.0 60 2.7

December 3.71 2.63 1.7 1.7 54 2.4

Total 78.01 60.55 40.2 6.7 46.9

Rainfall probably exceeded evapotranspiration for February.

Estimated from measurements for only half of August.

July and August periods would in turn need to be subtracted from the September and October values.

The total change of water stored in the 4to 16-inch layer of soil, based on laboratory data, was estimated to be about 1/2 inch.

While flow velocity of water through the profile cannot be measured explicitly, some indication of its direction was obtained by evaluating the hydraulic gradient tending to cause flow.

Values of the hydraulic gradient between the 12and 20-inch depths were such that downward flow occurred from January through June.

Monthly means of daily values varied from 0.5 to 0.05.

Values for July indicated flow was upward and the monthly mean hydraulic gradient was 21 for the month of August.

Values indicating upward flow were 8 for September, 2 for October, and 1 for November.

During December, the hydraulic gradient showed downward flow.

Conductivity values for the decomposed granitic subsoil, estimated from laboratory measurements, indicated that total flow, between the 12and 20-inch depths for any one month, probably did not exceed 0.1 inch.

Again no attempt was made to correct the amounts of applied water for this transfer in the soil profile.

A 14-inch diameter insulated evaporation pan was installed in August with the water elevation about level with the turf.

Evaporation values for the last four months of the year are included in the table.

All of the measurements indicated were made while the irrigation program was completely under automatic control.

The automatic controller called for irrigation over 100 times during the year.

This frequent irrigation with relatively low volume applications per irrigation appears to be well adapted for making evapotranspiration measurements.

With relatively few additional modifications, this approach could be used to measure evapotranspiration for the wide range of conditions under which turf is being grown.

S.

J.

Richards is Soil Physicist and L.

V.

Weeks, Laboratory Technician, Department of Soils and Plant Nutrition, University of California, Riverside.

Funds for purchasing irrigation equipment were provided by the Water Resources Center, University of California, Los Angeles.

Moist O'Matic, Incorporated, Riverside, California, contributed to the installation of the automatic sprinkler system.

The kickoff event is always one of mixed emotions for attendees, as you have the new participants that are entering with eager anticipation to get started, but also the past competitors that are attending to learn what has changed, as well as continue to network and build the peer-to-peer relationships that TAPS prides itself on, said TAPS Program Manager Krystle Rhoades.

Selection and Management of Efficient Hand-move Solid Set and Permanent Irrigation System

Prepared by: Robert Evans, Extension Agricultural Engineering Specialist R.E.

Sneed, Extension Agricultural Engineering Specialist

Published by: North Carolina Cooperative Extension Service Publication Number: EBAE-91-152 Last Electronic Revision: June 1996

Rainfall is the principle source of water for North Carolina crops.

However, many farmers are turning to irrigation to supplement precipitation.

There are many types of irrigation systems.

But, most farmers have limited choices for their particular farm or field.

Some systems are inherently more water and energy efficient while others are designed to overcome limitations such as irregular field shapes, sloping land, or limited water supplies.

All of these factors should be considered before selecting a particular type of system.

Hand-move systems are normally used to irrigate small fields.

Solid-set and permanent sprinkler irrigation systems are used for irrigation, frost/freeze protection, evaporative cooling, and land application of nutrient-rich effluent.

Selection and management considerations for hand-move solidset and permanent sprinkler irrigation systems are discussed in this article.

Selection and management criteria for other types of irrigation systems are presented in articles EBAE 91-150: Self-Propelled Gun Traveler Irrigation Systems, EBAE 91-151: Center Pivot and Linear Move Irrigation Systems, and EBAE 91153: Low Volume Irrigation Systems.

Sprinkler irrigation systems have been available for more than 70 years.

The early systems used lightweight steel pipe and nonrotating sprinklers.

Rotary impact sprinklers were introduced in the late thirties.

However, it was not until after World War II, when aluminum pipe became available, that portable hand-move system became practical.

Most of the early rotary impact sprinklers were low capacity, medium pressure, and constructed of brass.

Some companies supplied gun sprinklers, but early models were not very satisfactory, because of the high application rate and potential for runoff.

Over the years, the trend has been toward larger sprinklers.

Several companies now supply a low capacity gun sprinkler which has reduced some of the runoff problems typically associated with gun type sprinklers.

Sprinklers are now available with plastic, brass, aluminum, and some stainless steel components.

Improvements in bearings contribute to longer life and less maintenance.

Quality control has also improved.

The major change in aluminum pipe has been a trend toward thinner wall aluminum pipe and stronger alloys.

Couplers and gaskets have been improved to reduce leaks at joints.

The number of coupler manufacturers has been reduced.

Most of these changes have occurred because of the introduction of other types of irrigation systems such as self-propelled gun travelers, center pivots, linear move, low volume, and sub-irrigation.

Sprinkler spacing's for portable irrigation systems range from 40 feet by 40 feet for small sprinklers to greater than 200 feet by 200 feet for gun sprinklers.

Spacing's may be square, rectangular, or triangular.

Spacing's are usually about 60 percent of sprinkler wetted diameter, but may need to be adjusted for wind conditions.

Singleor double-nozzle sprinklers may be used.

The doublenozzle sprinkler generally provides better uniformity, because the second nozzle provides water close to the sprinkler.

Smaller sprinklers, because they are less affected by wind, provide better uniformity than gun sprinklers.

However, the labor required for moving pipe when smaller sprinklers are used is increased considerably.

Figure 1 shows a typical layout of a portable hand-move aluminum pipe system.

Two laterals are operated at one time.

Spacing between sprinklers is 60 feet and spacing between laterals is 60 feet.

The first and last sprinklers on each lateral are 30 feet from the edge of the field.