Soil water potential upper limit and lower limit during irrigation

The upper limit and lower limit of soil water potential during irrigation

Modern water-saving irrigation methods such as sprinkler irrigation, drip irrigation, etc. provide the possibility to achieve accurate and timely irrigation of crops, and also put forward higher requirements for the measurement and evaluation of soil moisture status. It is a wrong theory to judge the state of soil drought by using soil moisture. Now it is generally used to determine the soil drought condition. The soil water potential can be measured using a digital tension meter.

When irrigating, pay attention to the amount of irrigation and pay attention to the appropriate lower limit and upper limit of soil moisture. Most of the terrestrial plants need water mainly from the soil. But not all the water in the soil is available to plants. The amount of water retained in the soil without being affected by gravity is called the field water holding capacity, which is the upper limit of the water normally used by plants. The soil moisture content when the plant is permanently wilting is called the wilting coefficient or percentage of permanent wilting (PWP), which is the lower limit of the available water of the plant. Usually, when the soil moisture is maintained at the field water holding rate, it is most beneficial to the growth of the plants. When the moisture in the soil is higher than the field water holding rate, it is not conducive to the roots of plants to breathe, and at the same time, the growth of plants is affected. In irrigation, if the water potential of the soil reaches the percentage of permanent wilting, irrigation is not needed. The soil moisture is not as good as possible, and it is not as good as possible. To be suitable, it is necessary to promote the growth of the plant.

The digital tension meter can be used to detect and observe the soil water potential in the field, so as to further obtain soil water parameters such as soil moisture and hydraulic conductivity. This instrument is portable and easy to carry outside to operate, and it is convenient to operate. It can automatically capture the peak water potential function, which is more convenient for us to observe and understand the change of soil water potential. When recording the soil water potential, we can record the temperature, water potential, time, and storage serial number at the same time. Let us understand the change of soil water potential in different periods. course.