Plants need water to transport nutrients through the plant, for cell development and temperature control. Available moisture moves from the root hairs to the leaves. As soil moisture levels drop the plants ability to draw moisture declines. If inadequate moisture is available or evaporation from the leaf surface exceeds the rate at which water can be moved upward then the plant goes into water related stress. Plants differ in their ability to respond to stress conditions.
How we take care for water management:
1. Calculates water quality.
2. Predicts irrigation water EC.
4. Residual Alkalinity.
5. Predicts irrigation water pH.
6. Calculates TDS.
7. Calculates SAR.
8. Predicts EC based on water analysis.
Evapotranspiration (ET) is the amount of water lost from the soil or leaf surface by evaporation and water used by the plants through transpiration.
The use of a landscape coefficient (KL) is a relatively new concept. The advantage of using KL for landscapes instead of the traditional "crop coefficient" (Kc) is that the KL value can be adjusted for the microclimate (Kmc) and planting density (Kd) impacts upon the plant water requirement as well as for the specific species(Ks). However, KL cannot be used if its Ks factor is unknown.
KL is a dimensionless landscape coefficient that takes into account the specific water requirement of a landscape plant species and also the environment where the plant is growing. Environmental conditions include microclimate, such as shade or sun exposure, and density of planting.
KL is calculated from:
KL = Ks x Kmc x Kd
KL= Site-specific landscape coefficient.
Ks = Adjustment factor representing characteristics for a particular plant species.
Kmc = Adjustment factor for microclimate influences on the plant.
Kd = Adjustment factor for plant density.
How we take care for water management:
The plant water requirement can be calculated based on Reference ET and a crop or landscape coefficient for a specific period of time.
ETc = ETo x Kc or KL
ETc = Plant Water Requirement
ETo = Reference Evapotranspiration
Kc = Crop Coefficient
KL = Landscape Coefficient
This is the amount of water lost from the landscape resulting in soil moisture depletion. Plants draw water from the soil reservoir. Once the soil reservoir level drops to an allowable level it must be replenished with either rain or irrigation.
The soil is a habitat for soil organisms and plant roots. It functions as a storehouse for nutrients and a water reservoir. It contains and supplies water oxygen nutrients and mechanical support for plant growth. The amount of water the soil can hold is determined by soil properties. This amount determines how long a plant can be sustained before the soil moisture is replenished by irrigation or rain. Soil properties are important to proper operation and management of irrigation systems. These properties include soil texture, intake characteristics, water holding capacities and capillary movement.
Soil texture refers to the proportion of sand, silt, and clay found in the soil profile. It defines the fineness or coarseness of a soil. Fine textured soils generally hold more water than coarse textured soils. Medium textured soils actually have more available water for plant use than some clay soils. The size and shape of individual soil particles such as sand, silt, or clay describes the soil texture. Soil texture largely determines the amount of water that can be stored in a soil, as well as soil infiltration rate and soil permeability. Soil infiltration rate is the rate at which water enters the soil. Permeability is the rate at which water moves through the soil.
The irrigation requirement is based on the plant water requirement minus effective rainfall. Soil moisture depletes over time because of evapotranspiration. Rain also occurs over time. The need to irrigate is based on a combination of accumulated ETc minus effective rainfall. The industry refers to this as the soil moisture balance or the Checkbook method of irrigation management. Four factors affect the soil moisture balance.
1. Moisture loss by evapotranspiration.
2. Drainage below the root-zone.
3. Effective rain.
Irrigation should occur only when the plants truly need it and cannot readily get it from the root zone. To maintain healthy plants soil moisture should be depleted to a manageable level before irrigating. If watering always occurred daily, based on the irrigation requirement, deep root systems are not developed. Less frequent and deeper watering encourages healthy roots, which improves stress tolerance in the summer.
IR = ET ER
IR = Irrigation Requirement
ETc = Crop specific ET
ER = Effective Rain
The irrigation requirement is accumulated as a balance of depleted soil moisture
rrigation control systems are not to be set and forgotten. An irrigation system is complex combination of sprinkler heads, piping systems, valves and electronics that is designed installed and managed to meet the plant water requirement. There are too many things that can go wrong. When the system fails to maintain a healthy landscape the entire system needs to be evaluated to determine the cause and then take whatever action is need to correct the problem.
HRole of Israel Agro Consult in Water Management:
We invite papers describing interactions involving agricultural water management and the environment. Examples of topics within this category include flooding, soil erosion, nutrient loss and depletion, nonpoint source pollution, water quality, and desertification. In all cases, manuscripts must address implications and provide insight regarding agricultural water management.
Note: Our system resulted into increase by 50% to 90% in harvest in all major fruits and 2 to 3 times more in assorted vegetables.