Handbook for Irrigation of Wine Grapes in South Africa

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Chapter 8

Figure 8.23 500 m would require a second data logger and sensors. Since the instrumentation is relatively expensive, it might become too costly if soil water content needs to be measured in a large number of vineyards on bigger farms.

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FIGURE 8.23. EnviroScan ® sensors mounted on a shaft (A) before it is pushed down the PVC tube so that only the cover cap remains above-ground (B).

Installation: To obtain accurate and reliable soil water content measurements, it is essential that the access tubes for EnviroScan ® sensors make good contact with the surrounding soil. Since soil contact is so critical, it is recommended that the suppliers or other experts carry out the installation of EnviroScan ® probes, as well as setting up the loggers and necessary software. 8.4.1.5 DIVINER 2000® PROBES This instrument uses the same technology as the EnviroScan ® , and can therefore measure over the full plant available water range. However, it does not allow continuous soil water content monitoring. The Diviner 2000 ® probe consists of only one sensor mounted on the end of a shaft (Fig. 8.24). Soil water content (mm) is measured as the sensor is pushed down a PVC access tube, i.e. almost similar to neutron probe measurements. Since measurements are taken immediately at pre-set depths as the Diviner 2000 ® probe is pushed down the access tube, measurements are recorded quicker, compared to the neutron probe. Similar to the neutron probe, a single Diviner 2000 ® probe can be used to measure soil water content in an unlimited number of vineyards. Furthermore, using a Diviner 2000 ®

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