Document Type : Research Paper
Authors
1 Assistant Professor, Soil Conservation and Watershed Management Research Institute (SCWMRI), Agricultural Research, Education and Extension Organization (AREEO), Tehran, Iran
2 پژوهشکده حفاظت خاک و آبخیزداری
Abstract
One of the main challenge of water resources management in the Iran is the lack of sufficient water level and discharge data from the watersheds. This is more serious for small watersheds. Meanwhile, the use of water level data-loggers devices can significantly reduce the problems of collecting surface and groundwater resources. Several methods have been developed for this purpose, which can be divided into two main procedures: contact and non-contact (depending on the sensor in direct contact with water or out of water). The use of non-contact methods, if they have good accuracy, have the advantage of stable water conditions, especially water density, as well as longer useful life. One non-contact method of measuring distance changes is application of infrared sensors. Therefore, in this paper, the ability to measure water level changes using the Sharp infrared module model GP2Y0A21YK0F was investigated. This module is inexpensive and, compared to other non-contact sensors, uses a triangular method to detect distances, so the reflection variability of objects, ambient temperature, and reflection time have no effect on sensor performance. However, due to the need for an impenetrable light-absorbing surface, this method was combined with the old method of using floats on the water surface. The results show that the mentioned sensor estimates the water level changes in the environment with an error of 2 cm. By increasing the range of the minimum measurement range of the sensor from 20 to 30 cm, the measurement error is reduced to 1.34 cm. It should be noted that when used in flooded environments, it is associated with several problems. Therefore, it is not recommended to measure the water level inside flood canals, and to increase the capability of this device, the use of other sensors such as pressure or ultrasonic sensors should be considered.
Keywords
)