Waterwijzer Overlay

The waterwijzer overlay provides the yield loss of crops based on several input parameters. The yield loss is currently calculated by the Waterwijzer Landbouw module, which is described here.

Usage

The Waterwijzer Overlay results can be used to:

Calculate the yield loss based on existing crops for currently known highest and lowest groundwater levels.
Calculate the yield loss for crops when using different groundwater level management strategies simulated by a Groundwater Overlay or a Subsidence Overlay.
Determine the best type of crop per parcel given the highest and lowest groundwater levels and type of soil.

Considerations

The Waterwijzer Overlay calculates yield loss for agriculture crops based on:

A climate scenario;
A weather station;
Type of soil;
Type of crop;
Highest and lowest (averaged) groundwater levels;
The irrigation parameter, which in the Waterwijzer tool is active for a number of the crop types, is currently not taken into account.
The version of the Waterwijzer tool, for which we currently always use 2.0.0.

Result types

The overlay offers multiple result types. Each result type expresses the yield loss due to specific circumstances as a percentage.

Result type	Unit	Description
DAMAGE_DRY	% yield loss	The loss of agricultural yield due to low groundwater levels.
DAMAGE_WET	% yield loss	The loss of agricultural yield due to high groundwater levels.
DAMAGE_INDIRECT	% yield loss	The loss of agricultural yield due to indirect causes.
DAMAGE_SALT	% yield loss	The loss of agricultural yield due to salt water irrigation or ground bottom flow with salt water.
DAMAGE_TOTAL	% yield loss	The total loss of agricultural yield for a particular crop.

How-to's

Module

A Waterwijzer Overlay can be configured by opening the Waterwijzer Overlay Wizard. More in-depth information can be found under each of the categories below.