Checking and Planning in Water Yield
There might be a concept problem in my study that is "what the water yield means in fact?". For example I calculated the water yield in an area and i want to check whether it is right in. Some people compared it with total water resources in this area including underground water and surface water, and others compared it with surface water only. And sometimes we can only compared with the volume of runoff. what data can we use to calibrate the water yield and took it as the standard?