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| | | {{Back to Irrigate}} | | | {{Back to Irrigate}} |
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| − | | style="width: 150px; background-color: rgb(222, 226, 192);" | <span style="color:#000000;"><span style="font-size: 90%">'''[[SPIS Toolbox - Establish and Refine Maintenance Plan|►Go to the Next Chapter]]'''</span></span> | + | | {{Next Chapter}}[[SPIS Toolbox - Establish and Refine Maintenance Plan|►Go to the Next Chapter]]'''</span></span> |
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| − | === '''<span style="color:#879637;">7. Irrigation Efficiency Tips</span>''' === | + | === '''<span style="color: rgb(135, 150, 55);">7. Irrigation Efficiency Tips</span>''' === |
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| | Irrigation water is a precious resource. This not only applies directly to agricultural production, but also indirectly to the ecosystem at large. The wise use and conservation of irrigation water is hence essential. A number of best practices and tips can reduce overall water consumption, improve plant growth and lead to higher yields. | | Irrigation water is a precious resource. This not only applies directly to agricultural production, but also indirectly to the ecosystem at large. The wise use and conservation of irrigation water is hence essential. A number of best practices and tips can reduce overall water consumption, improve plant growth and lead to higher yields. |
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| − | ==== <span style="color:#879637;">Map it Out</span> ==== | + | ==== <span style="color: rgb(135, 150, 55);">Map it Out</span> ==== |
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| | Review the layout of the land and map the optimal placement of irrigation piping, with attention to reducing the number of fittings used (prone to leakages). Keep in mind that slopes would cause an uneven distribution of water and could result in run-off. Hence levelling and terracing is advised when using flood or sprinkler irrigation (drip lines should run horizontal to the slope). Sprinkler irrigation disperses water in a circle around the central nozzle. Determine the radius and place sprinklers in such a fashion that overlaps are kept to a minimum, while still ensuring that a maximum area is covered (i.e. few dry areas remain). | | Review the layout of the land and map the optimal placement of irrigation piping, with attention to reducing the number of fittings used (prone to leakages). Keep in mind that slopes would cause an uneven distribution of water and could result in run-off. Hence levelling and terracing is advised when using flood or sprinkler irrigation (drip lines should run horizontal to the slope). Sprinkler irrigation disperses water in a circle around the central nozzle. Determine the radius and place sprinklers in such a fashion that overlaps are kept to a minimum, while still ensuring that a maximum area is covered (i.e. few dry areas remain). |
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| − | ==== <span style="color:#879637;">Preserve Trees</span> ==== | + | ==== <span style="color: rgb(135, 150, 55);">Preserve Trees</span> ==== |
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| | Ideally, large trees should remain in the crop area. Not only do they provide moving shade, but certain species (e.g. acacias) support nitrogen-fixing bacteria which enhance soil fertility. | | Ideally, large trees should remain in the crop area. Not only do they provide moving shade, but certain species (e.g. acacias) support nitrogen-fixing bacteria which enhance soil fertility. |
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| − | ==== <span style="color:#879637;">Agroecological Approach</span> ==== | + | ==== <span style="color: rgb(135, 150, 55);">Agroecological Approach</span> ==== |
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| | The [http://www.fao.org/agroecology/en/ ten agro-ecological principles] outlined by the FAO highlight aspects that relate to water resources, use, reuse, governance, and rights. These principles also provide a means to look beyond the farm level intervention to impacts in the wider community and food system. | | The [http://www.fao.org/agroecology/en/ ten agro-ecological principles] outlined by the FAO highlight aspects that relate to water resources, use, reuse, governance, and rights. These principles also provide a means to look beyond the farm level intervention to impacts in the wider community and food system. |
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| − | The [[:File:IRRIGATE Impact Assessment Tool V1.0.xlsx|IRRIGATE – Impact Assessment Tool]] incorporates, to some extent, these principles. | + | The [[:file:PROMOTE & INITIATE – Impact Assessment Tool.xlsx|PROMOTE & INITIATE – Impact Assessment Tool]] incorporates, to some extent, these principles. |
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| − | ==== <span style="color:#879637;">Soil Testing</span> ==== | + | ==== <span style="color: rgb(135, 150, 55);">Soil Testing</span> ==== |
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| − | [[File:Sedimentation Layers.png|thumb|150px|Sedimentation layers in the soil jar test (Source: K Blumenthal)]] [[File:Soil Texture Triangle.JPG|thumb|150px|The Soil Texture Triangle (Source: United States Department of Agriculture)]] Soil moisture available to plant roots is depended on soil type. The soil type can be determined in the laboratory using a particle size analysis. Sand, silt and clay have different diameters, by sieving them their distribution delivers information about the soil type. Another way to determine the soil type is the "Jar Test": | + | [[File:Sedimentation Layers.png|thumb|150px|Sedimentation layers in the soil jar test (Source: K Blumenthal)]] [[File:Soil Texture Triangle.JPG|thumb|150px|The Soil Texture Triangle (Source: United States Department of Agriculture)]] Soil moisture available to plant roots is dependent on soil type. The soil type can be determined in the laboratory using a particle size analysis. Sand, silt and clay have different diameters, by sieving them their distribution delivers information about the soil type. Another way to determine the soil type is the "Jar Test": |
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| | #Remove soil from the zone to be irrigated | | #Remove soil from the zone to be irrigated |
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| | Putting in the obtained percentages of clay, silt and sand, a soil texture triangle, as seen in the figure below, shows the type of soil present. | | Putting in the obtained percentages of clay, silt and sand, a soil texture triangle, as seen in the figure below, shows the type of soil present. |
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| − | The '''[[:file: IRRIGATE – Soil Tool V1.0.xlsx|IRRIGATE– Soil Tool]]''' describes the different soil type properties and allows for establishing a soil-based irrigation schedule according to different crops. | + | The '''[[Media:IRRIGATE - Soil Tool.xlsm|IRRIGATE– Soil Tool]]''' describes the different soil type properties and allows for establishing a soil-based irrigation schedule according to different crops. |
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| − | ==== <span style="color:#879637;">Irrigation Scheduling</span> ==== | + | ==== <span style="color: rgb(135, 150, 55);">Irrigation Scheduling</span> ==== |
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| − | Scheduling irrigation based on soil-plant or atmosphere measurements can decrease water use while improving yields. Software programs can collect weather data including local temperature, rainfall, humidity, and crop evapotranspiration to provide recommendations for optimal irrigation scheduling (see [http://www.fao.org/docrep/X0490E/X0490E00.htm FAO Irrigation and Drainage Paper 56]). The '''[[:file:IRRIGATE – Soil Tool V1.0.xlsx|IRRIGATE– Soil Tool]]''' allows for establishing a soil-based irrigation schedule according to different crops. | + | Scheduling irrigation based on soil-plant or atmosphere measurements can decrease water use while improving yields. Software programs can collect weather data including local temperature, rainfall, humidity, and crop evapotranspiration to provide recommendations for optimal irrigation scheduling (see [http://www.fao.org/docrep/X0490E/X0490E00.htm FAO Irrigation and Drainage Paper 56]). The '''[[Media:IRRIGATE - Soil Tool.xlsm|IRRIGATE – Soil Tool]]''' allows for establishing a soil-based irrigation schedule according to different crops.<br/> |
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| − | ==== <span style="color:#879637;">Mulch</span> ==== | + | ==== <span style="color: rgb(135, 150, 55);">Mulch</span> ==== |
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| − | Mulching is an effective technique to reduce evaporation of soil moisture, insulate against cold weather and gradually enhance the organic composition of soils. It helps to prevent soil compaction, acts as a soil conditioner, and encourages the presence of natural aerators, like earthworms. It adds nutrients by contributing to the availability of potassium and can add nitrogen, phosphorus, and trace elements to the soil. Furthermore it is an ideal way to make use of recycled crop waste. | + | Mulching is an effective technique to reduce evaporation of soil moisture, insulate against cold weather and gradually enhance the organic composition of soils. It helps to prevent soil compaction, acts as a soil conditioner, and encourages the presence of natural aerators, like earthworms. It adds nutrients by contributing to the availability of potassium and can add nitrogen, phosphorus, and trace elements to the soil. Furthermore, it is an ideal way to make use of recycled crop waste.<br/> |
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| | Mulching comprises the layering of organic (straw, wood bark, leaf litter, maize stalks) or inorganic (PVC sheeting) materials over the crop area, through which the crops can grow. Mulching can also be achieved through intercropping, by for instance planting ground creepers (water melon, pumpkin) between rows of maize. Important considerations regarding mulching include: | | Mulching comprises the layering of organic (straw, wood bark, leaf litter, maize stalks) or inorganic (PVC sheeting) materials over the crop area, through which the crops can grow. Mulching can also be achieved through intercropping, by for instance planting ground creepers (water melon, pumpkin) between rows of maize. Important considerations regarding mulching include: |
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| | *Before applying a new layer of mulch, rake through and mix the older mulch layer. Mulch, especially from woody materials, can compact over time and thus prevent soil aeration and water penetration. | | *Before applying a new layer of mulch, rake through and mix the older mulch layer. Mulch, especially from woody materials, can compact over time and thus prevent soil aeration and water penetration. |
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| − | ==== <span style="color:#879637;">Intercropping</span> ==== | + | ==== <span style="color: rgb(135, 150, 55);">Intercropping</span> ==== |
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| | Intercropping is a multiple cropping practice involving growing two or more crops in proximity. The most common goal of intercropping is to produce a greater yield on a given piece of land by making use of resources or ecological processes that would otherwise not be utilized by a single crop (''Ouma, George; Jeruto, P (2010)''). The elements of intercropping (''Wikipedia, “Intercropping”, January 2018'') include: | | Intercropping is a multiple cropping practice involving growing two or more crops in proximity. The most common goal of intercropping is to produce a greater yield on a given piece of land by making use of resources or ecological processes that would otherwise not be utilized by a single crop (''Ouma, George; Jeruto, P (2010)''). The elements of intercropping (''Wikipedia, “Intercropping”, January 2018'') include: |
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| | Agricultural extension officers and advisors should be able to give guidance regarding intercropping and companion planting. | | Agricultural extension officers and advisors should be able to give guidance regarding intercropping and companion planting. |
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| − | ==== <span style="color:#879637;">Rainwater Catchment</span> ==== | + | ==== <span style="color: rgb(135, 150, 55);">Rainwater Catchment</span> ==== |
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| | Ensuring that rainwater does not run-off, but percolates into deeper soil layers avoids top soil erosion and can improve groundwater recharge, while improving soil moisture at depth. Strategically placed furrows can trap rainwater and divert it to crop areas (or the pump well), while roof gutters leading to water storage tanks can build up reserves for the dry season. | | Ensuring that rainwater does not run-off, but percolates into deeper soil layers avoids top soil erosion and can improve groundwater recharge, while improving soil moisture at depth. Strategically placed furrows can trap rainwater and divert it to crop areas (or the pump well), while roof gutters leading to water storage tanks can build up reserves for the dry season. |
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| − | ==== <span style="color:#879637;">Monitoring</span> ==== | + | ==== <span style="color: rgb(135, 150, 55);">Monitoring</span> ==== |
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| | Monitoring water consumption and soil moisture levels regularly, ensures a deeper understanding of the water resources necessary for healthy crops. Water flow meters and hand-held soil moisture meters are important devices through which data is collected and recorded for analysis. | | Monitoring water consumption and soil moisture levels regularly, ensures a deeper understanding of the water resources necessary for healthy crops. Water flow meters and hand-held soil moisture meters are important devices through which data is collected and recorded for analysis. |
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| − | ==== <span style="color:#879637;">Improved Furrows</span> ==== | + | ==== <span style="color: rgb(135, 150, 55);">Improved Furrows</span> ==== |
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| | Numerous techniques exist to optimize water flow through furrows. These may include covering furrows with plastic PVC sheeting or rock slabs to reduce evaporation, lining or firming main furrows to reduce water infiltration rate at the head end of the field (then additional water is available to advance further down the furrow. The result is faster advance time to the end of the field and improved water distribution) or optimizing slope angles to ensure efficient water flow. | | Numerous techniques exist to optimize water flow through furrows. These may include covering furrows with plastic PVC sheeting or rock slabs to reduce evaporation, lining or firming main furrows to reduce water infiltration rate at the head end of the field (then additional water is available to advance further down the furrow. The result is faster advance time to the end of the field and improved water distribution) or optimizing slope angles to ensure efficient water flow. |
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| − | ==== <span style="color:#879637;">Evaporation Avoidance</span> ==== | + | ==== <span style="color: rgb(135, 150, 55);">Evaporation Avoidance</span> ==== |
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| | Evaporation from uncovered water storage and water conveyance systems implies a direct loss of water resources to the atmosphere. This loss has financial implications where costs were incurred to pump the water from a well or procure it from a service provider. Stopping evaporation is a question of restricting the solar energy available to the water (to energise water molecules) and lowering its exposure to dry air. When water evaporates it forms a moist layer of air over the surface, lowering the capacity of the air to accept more water molecules from the liquid. Moving air draws water vapor away from the area over the surface of the water and replaces it with drier air, increasing evaporation. Using sealed tanks or covering open storage tanks and canals is advisable. For larger irrigation reservoirs or dams floating covers can be considered, along with wind breaks (e.g. hedges and trees) around the perimeter. The latter might also contribute towards shading the water surface, thus reducing the kinetic energy available to water molecules. | | Evaporation from uncovered water storage and water conveyance systems implies a direct loss of water resources to the atmosphere. This loss has financial implications where costs were incurred to pump the water from a well or procure it from a service provider. Stopping evaporation is a question of restricting the solar energy available to the water (to energise water molecules) and lowering its exposure to dry air. When water evaporates it forms a moist layer of air over the surface, lowering the capacity of the air to accept more water molecules from the liquid. Moving air draws water vapor away from the area over the surface of the water and replaces it with drier air, increasing evaporation. Using sealed tanks or covering open storage tanks and canals is advisable. For larger irrigation reservoirs or dams floating covers can be considered, along with wind breaks (e.g. hedges and trees) around the perimeter. The latter might also contribute towards shading the water surface, thus reducing the kinetic energy available to water molecules. |
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| − | ==== <span style="color:#879637;">Irrigation Timing</span> ==== | + | ==== <span style="color: rgb(135, 150, 55);">Irrigation Timing</span> ==== |
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| | In principle it is best to irrigate during the morning hours starting just before sunrise. Cooler air and lower wind speeds reduce evaporation losses, while crops are assured an adequate water supply at the root zone in preparation for higher daytime temperatures. Watering in the late afternoons and evenings is not advised, as crops cannot absorb the available water and stagnant water offers a breeding ground for pests and fungi. | | In principle it is best to irrigate during the morning hours starting just before sunrise. Cooler air and lower wind speeds reduce evaporation losses, while crops are assured an adequate water supply at the root zone in preparation for higher daytime temperatures. Watering in the late afternoons and evenings is not advised, as crops cannot absorb the available water and stagnant water offers a breeding ground for pests and fungi. |
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| − | ==== '''<span style="color:#879637;">Outcome/Product</span>''' ==== | + | ==== '''<span style="color: rgb(135, 150, 55);">Outcome/Product</span>''' ==== |
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| | *Understand some practical approaches towards reducing irrigation water demand | | *Understand some practical approaches towards reducing irrigation water demand |
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| − | ==== '''<span style="color:#879637;">Data Requirements</span>''' ==== | + | ==== '''<span style="color: rgb(135, 150, 55);">Data Requirements</span>''' ==== |
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| | *Information on intercropping and companion planting | | *Information on intercropping and companion planting |
| | *Soil properties in crop areas | | *Soil properties in crop areas |
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| − | ==== '''<span style="color:#879637;">People/Stakeholders</span>''' ==== | + | ==== '''<span style="color: rgb(135, 150, 55);">People/Stakeholders</span>''' ==== |
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| | *Agricultural extension officers and advisors | | *Agricultural extension officers and advisors |
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| | *Horticulture and permaculture specialists | | *Horticulture and permaculture specialists |
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| − | ==== '''<span style="color:#879637;">Important Issues</span>''' ==== | + | ==== '''<span style="color: rgb(135, 150, 55);">Important Issues</span>''' ==== |
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| | *Irrigation efficiency can only be ensured through active and regular monitoring. Any improvement measure should be scrutinized carefully before implementation and baseline information captured (e.g. amount of water consumed, amount of fertilizer added). Comparing the baseline information with the new post-measure data, allows to assess the success or failure of the improvement. This deepens understanding. | | *Irrigation efficiency can only be ensured through active and regular monitoring. Any improvement measure should be scrutinized carefully before implementation and baseline information captured (e.g. amount of water consumed, amount of fertilizer added). Comparing the baseline information with the new post-measure data, allows to assess the success or failure of the improvement. This deepens understanding. |
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| | {{SPIS Reference}} | | {{SPIS Reference}} |
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| | | {{Back to Irrigate}} | | | {{Back to Irrigate}} |
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| − | | style="width: 150px; background-color: rgb(222, 226, 192);" | <span style="color:#000000;"><span style="font-size: 90%">'''[[SPIS Toolbox - Establish and Refine Maintenance Plan|►Go to the Next Chapter]]'''</span></span> | + | | {{Next Chapter}}[[SPIS Toolbox - Establish and Refine Maintenance Plan|►Go to the Next Chapter]]'''</span></span> |
| | |} | | |} |
Irrigation water is a precious resource. This not only applies directly to agricultural production, but also indirectly to the ecosystem at large. The wise use and conservation of irrigation water is hence essential. A number of best practices and tips can reduce overall water consumption, improve plant growth and lead to higher yields.
Review the layout of the land and map the optimal placement of irrigation piping, with attention to reducing the number of fittings used (prone to leakages). Keep in mind that slopes would cause an uneven distribution of water and could result in run-off. Hence levelling and terracing is advised when using flood or sprinkler irrigation (drip lines should run horizontal to the slope). Sprinkler irrigation disperses water in a circle around the central nozzle. Determine the radius and place sprinklers in such a fashion that overlaps are kept to a minimum, while still ensuring that a maximum area is covered (i.e. few dry areas remain).
Ideally, large trees should remain in the crop area. Not only do they provide moving shade, but certain species (e.g. acacias) support nitrogen-fixing bacteria which enhance soil fertility.
Soil moisture available to plant roots is dependent on soil type. The soil type can be determined in the laboratory using a particle size analysis. Sand, silt and clay have different diameters, by sieving them their distribution delivers information about the soil type. Another way to determine the soil type is the "Jar Test":
Putting in the obtained percentages of clay, silt and sand, a soil texture triangle, as seen in the figure below, shows the type of soil present.
Scheduling irrigation based on soil-plant or atmosphere measurements can decrease water use while improving yields. Software programs can collect weather data including local temperature, rainfall, humidity, and crop evapotranspiration to provide recommendations for optimal irrigation scheduling (see FAO Irrigation and Drainage Paper 56). The IRRIGATE – Soil Tool allows for establishing a soil-based irrigation schedule according to different crops.
Mulching is an effective technique to reduce evaporation of soil moisture, insulate against cold weather and gradually enhance the organic composition of soils. It helps to prevent soil compaction, acts as a soil conditioner, and encourages the presence of natural aerators, like earthworms. It adds nutrients by contributing to the availability of potassium and can add nitrogen, phosphorus, and trace elements to the soil. Furthermore, it is an ideal way to make use of recycled crop waste.
Mulching comprises the layering of organic (straw, wood bark, leaf litter, maize stalks) or inorganic (PVC sheeting) materials over the crop area, through which the crops can grow. Mulching can also be achieved through intercropping, by for instance planting ground creepers (water melon, pumpkin) between rows of maize. Important considerations regarding mulching include:
Intercropping is a multiple cropping practice involving growing two or more crops in proximity. The most common goal of intercropping is to produce a greater yield on a given piece of land by making use of resources or ecological processes that would otherwise not be utilized by a single crop (Ouma, George; Jeruto, P (2010)). The elements of intercropping (Wikipedia, “Intercropping”, January 2018) include:
Agricultural extension officers and advisors should be able to give guidance regarding intercropping and companion planting.
Ensuring that rainwater does not run-off, but percolates into deeper soil layers avoids top soil erosion and can improve groundwater recharge, while improving soil moisture at depth. Strategically placed furrows can trap rainwater and divert it to crop areas (or the pump well), while roof gutters leading to water storage tanks can build up reserves for the dry season.
Monitoring water consumption and soil moisture levels regularly, ensures a deeper understanding of the water resources necessary for healthy crops. Water flow meters and hand-held soil moisture meters are important devices through which data is collected and recorded for analysis.
Numerous techniques exist to optimize water flow through furrows. These may include covering furrows with plastic PVC sheeting or rock slabs to reduce evaporation, lining or firming main furrows to reduce water infiltration rate at the head end of the field (then additional water is available to advance further down the furrow. The result is faster advance time to the end of the field and improved water distribution) or optimizing slope angles to ensure efficient water flow.
Evaporation from uncovered water storage and water conveyance systems implies a direct loss of water resources to the atmosphere. This loss has financial implications where costs were incurred to pump the water from a well or procure it from a service provider. Stopping evaporation is a question of restricting the solar energy available to the water (to energise water molecules) and lowering its exposure to dry air. When water evaporates it forms a moist layer of air over the surface, lowering the capacity of the air to accept more water molecules from the liquid. Moving air draws water vapor away from the area over the surface of the water and replaces it with drier air, increasing evaporation. Using sealed tanks or covering open storage tanks and canals is advisable. For larger irrigation reservoirs or dams floating covers can be considered, along with wind breaks (e.g. hedges and trees) around the perimeter. The latter might also contribute towards shading the water surface, thus reducing the kinetic energy available to water molecules.
In principle it is best to irrigate during the morning hours starting just before sunrise. Cooler air and lower wind speeds reduce evaporation losses, while crops are assured an adequate water supply at the root zone in preparation for higher daytime temperatures. Watering in the late afternoons and evenings is not advised, as crops cannot absorb the available water and stagnant water offers a breeding ground for pests and fungi.
