PRISM-19


Monitoring Networks

Permanent Monitoring Stations

OzNet Network

Each site of the monitoring network (Smith et al., 2012) measures the soil moisture at 0-5 cm, 0-30 cm, 30-60 cm and 60-90 cm with water content reflectometers (Campbell Scientific). Reflectometers consist of a printed circuit board connected to two parallel stainless steel rods that act as wave guides. They measure the travel time of an output pulse to estimate changes in the bulk soil dielectric constant. The period is converted to volumetric water content with a calibration equation parameterised with soil type and soil temperature. Such sensors operate in a lower range of frequencies (10- 100 MHz) than Time Domain Reflectometers TDR (700- 1000 MHz).

Typical equipment at the original (2001) and new (2004) soil moisture sites in the Murrumbidgee catchment

SMAPEx Network

The 24 additional soil moisture sites were installed in late 2009 to support the Soil Moisture Active Passive Experiment (SMAPEx) project. These continuously monitor soil moisture at 0-5 cm with a Hydraprobe and soil temperature at 1, 2.5 and 5 cm depths (Unidata® 6507A/10 Sensors). The sites were installed to monitor as much of the variety of land cover conditions in the area as possible. The network is equally distributed between irrigated cropping land (occupying approximately 1/3 of the PRISM study area) and grazing dry land.

Schematic layout of the SMAPEx monitoring site and photo of site YA5.

Temporary Monitoring Stations

Permanent monitoring stations are supplemented by two identical temporary monitoring stations, one at each of the northern and southern focus areas. These short-term monitoring stations are instrumented with a rain gauge, thermal infrared sensor (Apogee), leaf wetness sensor (MEA LWS v1.1), two soil moisture sensors (Hydraprobes; 0-5 cm, 5-10 cm, 10-15cm, 15-20cm, 20-25cm and 25-30 cm) and four soil temperature sensors (MEA6507A; 2.5 cm, 5 cm, 15 cm and 40 cm depth) in order to provide time series data during the sampling period.

Schematic of the temporary monitoring station

Schematic of the temporary monitoring station

PLEASE NOTE: The following data sets should be acknowledged according to the following:

PRISM-19:

X. Wu, N. Ye, J. Walker, I.-Y. Yeo, T. Jackson, Y. Kerr, E. Kim and A. McGrath. (2019). The P-band Radiometer Inferred Soil Moisture Experiment 2019 WORKPLAN. Monash University, 121.