This is the water (from the Medium Pores) that is available to the plant. It is the difference between Saturation and Field Capacity. This is the water that drains (from the Large Pores) from the Saturated soil until the soil is at Field Capacity. This level is different for different species of plants. The plant will wilt (lose turgidity) and not recover (die). The water tightly adheres to the soil particles. This is the Soil Moisture level at which the plant cannot extract any water from the soil. Typically this is by Evaporation from the ground's surface and Transpiration by the Plants ( Evapotranspiration). The water in the Medium Pores ( Plant Available Water) has gone. Water remains in the soil and is available to the plants. The water in the soil does not drain (in practical terms) when the Soil Moisture is at or below Field Capacity. The water remaining has sufficiently bonded (adhered) to the soil that it no longer drains. This is the Soil Moisture level that is left after draining by gravity (say 30 minutes to 24 hours depending on the soil). Water is held in the Medium and Small Pores. The water held in the Large Pores ( Gravitational Water) has drained away. Water movement can be relatively quick in saturated soils (normally downward by gravity unless constrained). This is the maximum water holding capacity of the soil. Water fills all the pore space (Large, Medium and Small Pores) When discussing Soil Moisture, we often refer to the following three defined levels of Soil Moisture: Saturated These pores can be filled with air or water. Soil consists of solid particles and pores (voids). Without knowing these terms, it is difficult to communicate. These terms and an intuitive understanding of them are fundamental to learning about Soil Moisture. The main references used to create this article.
#Volumetrix soil moisture how to
This explains how to get started by using a simple, portable Soil Moisture Probe and how to progress from there. Then we introduce the concepts of Water Retention and Release Curves.Ī brief explanation of the role of salt decreasing the plant's ability to draw water from the ground.
#Volumetrix soil moisture series
We explain the concept with a series of graphics and an animated graphic showing water flow through a perched water table. The concept of a Perched Water Table is generally not properly understood.
![volumetrix soil moisture volumetrix soil moisture](https://www.researchgate.net/profile/Natalia-Restrepo-Coupe/publication/251428381/figure/fig2/AS:670033239879714@1536759781879/Soil-moisture-conditions-a-Volumetric-water-content-VWC-from-monthly-in-situ.png)
The 4 fundamental potentials (forces) that move water are explained. Also why Soil Moisture is making the inroads into irrigation so strongly now. We explain why weather stations, though fundamentally flawed, have been used for so long. It also looks at different irrigation strategies and the importance of rootzone depth in determining this. It also explains the concepts behind irrigation scheduling, the timing and the application (volume). This includes the different classifications of soil, the typical walter holding capacities of soils and infliltration rates.Ī series of animated slides shows the movement of water through the root zone in a typical irrigation cycle compared to over-irrigation and leaching cycles. Also how it relates to Field Capacity, Saturated Soils and the Equivalent Depth of Water.Ī description of soil properties as related to Soil Moisture. The measurement of Soil Moisture Content by Volumetric Water Content (%) is explained. These are the terms you need to understand to learn about Soil Moisture. I acknowledge the time and effort that Laszlo Vranyak has put in producing most of the great graphics for this article. Misconceptions result in failed projects and wasted effort ($$$). Understanding Soil Moisture Concepts allows us to irrigate efficiently and have effective drainage systems with healthy turf/plants. However, its impact is seen on the surface with poor quality plants and water-logged soils. Soil Moisture is poorly understood since it occurs underground, away from our eyes. This basic knowledge of Soil Moisture Concepts is essential to managing the water in the soil, achieving irrigation efficiency, having effective drainage and good plant condition. Others may call this Soil-Water-Plant Relationships.
![volumetrix soil moisture volumetrix soil moisture](https://www.sensoterra.com/uploads/images/Content/Soil_Moisture_Interpretation_Volumetric_1.png)
Welcome to Hydrogold's Soil Moisture Concepts page. HYDROGOLD - An Introduction to Soil Moisture Concepts