Tarah Balden, scientist, Yurok Tribe looking at data logger

A soil moisture data logger buried in the ground is a specialized instrument designed to measure and record the moisture content of soil over time. Here's how it generally functions:

1. Measurement: The data logger uses sensors, often referred to as soil moisture sensors or probes, which are inserted into the soil. These sensors can use various technologies, such as capacitance, impedance, or time-domain reflectometry, to assess the amount of water present in the soil. The principle behind these technologies involves detecting changes in the electrical properties of the soil that correlate with moisture levels.
2. Data Recording: The data logger is equipped with a memory component to store the moisture data at set intervals. This could range from every few minutes to hourly, depending on the settings configured by the user or the requirements of the research.
3. Protection from Environmental Factors: Being buried underground, particularly at a depth that is less affected by surface conditions such as fires, helps protect the logger from extreme temperatures, fire damage, and other environmental influences. The burial depth is chosen based on factors like the soil type, the depth of interest for moisture measurement, and potential environmental threats.
4. Data Retrieval and Analysis: The collected data can be retrieved manually by excavating the logger or, in more advanced systems, transmitted wirelessly to a nearby receiver or directly to a satellite. This data is then analyzed to understand soil moisture dynamics, which can be crucial for agricultural planning, irrigation management, and studying ecological and hydrological processes.
5. Long-Term Monitoring: These devices are typically designed for long-term deployment, allowing continuous monitoring over seasons or years to gather long-term data trends, which is valuable for research on climate change impacts, land management, and water resource management.

This buried setup not only ensures consistent functioning during regular conditions but also provides resilience against extreme events like wildfires, maintaining the integrity of the data collected during such events.