Name	Notation	Description	Types	Status
Gravimetric moisture determination	126	Measurement of the amount of water in soil by weighing a samp...	Concept	stable
Soil heat flux plate	128		Concept	stable
Neutron probe	159	Measurement of the moisture content and hence the porosity of...	Concept	stable
Electrical resistance blocks (Porous blocks)	187	Determination of electrical resistance between two electrodes...	Concept	stable
Soil thermometer	194		Concept	stable
Tensiometer	200	Measurement of soil capillary tension by means of a porous cu...	Concept	stable
Time domain reflectometry (TDR)	203	Estimation of water content in unsaturated materials based on...	Concept	stable
Ultrasonic ranging	260	Transmission of an ultrasonic pulse towards the target and li...	Concept	stable
Graduated device	261	Manual measurement or observation made with a graduated fixed...	Concept	stable
Snow pillows and snow scales	262	Weighing of snow-cover mass per unit area.	Concept	stable
Laser ranging	344	Emission of a modulated beam of light in the visible spectrum...	Concept	stable
Echo sounding	345	Evaluation of the return time of acoustic waves emitted into ...	Concept	stable
Frequency domain reflectometry	346	Measurement of soil capacitance by means of radio frequency w...	Concept	stable
Gamma-ray attenuation	347	Determination of gamma-ray attenuation at given depth of soil...	Concept	stable
Non-recording gauge	348	Determination of water stage by means of a non-recording gaug...	Concept	stable
Staff gauge	349	Determination of water stage by means of a graduated vertical...	Concept	stable
Inclined gauge	350	Determination of water stage by means of a non-vertical scale...	Concept	stable
Wire-weight gauge	351	Determination of water stage by means of a fine cable or wire...	Concept	stable
Point gauge	352	Level measurement gauge, the essential element of which is a ...	Concept	stable
Maximum-stage gauge	353	Determination of the elevation of the flood crest by the adhe...	Concept	stable
Recording gauge	354	Determination of water stage by means of a recording gauge, f...	Concept	stable
Wire-float recording gauge (hydrograph)	355	Determination of water stage by means of a gauge consisting o...	Concept	stable
Pressure-actuated recording gauge	356	Recording gauge operating on the principle that static pressu...	Concept	stable
Velocity-area method	357	Method of determining the discharge of a stream by measuring ...	Concept	stable
Float gauging	358	Measurement of the velocity of a stream by means of timing th...	Concept	stable
Dilution gauging	359	Determination of the discharge of a stream by measuring the d...	Concept	stable
Slope-area method	360	Determination of the discharge in a reach which is based on t...	Concept	stable
Measuring weir	361	Determination of the discharge of a stream by means of a devi...	Concept	stable
Flume	362	Determination of the discharge of a stream by means of a man-...	Concept	stable
Stage-discharge relation	363	Determination of the discharge of a stream by means of a rela...	Concept	stable
Water current meter	364	Determination of water velocity by means of a current meter, ...	Concept	stable
Cup-type current meter	365	Determination of water velocity by means of a current meter w...	Concept	stable
Propeller-type current meter	366	Determination of water velocity by means of a current meter i...	Concept	stable
Acoustic (ultrasonic) velocity meter	367	Measurement of the difference in travel time of acoustic (ult...	Concept	stable
Acoustic doppler current profiler (ADCP)	368	An instrument that uses an acoustic doppler transducer to mea...	Concept	stable
Acoustic doppler current meter	369	Determination of stream velocity by means of an acoustic Dopp...	Concept	stable
Optical or nuclear suspended-sediment gauge	370	Determination of the decrease of intensity of a visible light...	Concept	stable
Gravimetric sediment measurement	371	Estimation of the total sediment in a water sample by allowin...	Concept	stable
Displacement method of sediments	372	Determination of sediment concentration by the measurement of...	Concept	stable
Water discharge-sediment discharge rating curve	373	An empirical relationship relating sediment discharge and str...	Concept	stable
Water discharge-bed material rating curve	374	An empirical relationship relating bed-material discharge and...	Concept	stable
Volumetric method	375	A process for measuring the discharge of a well, spring, or s...	Concept	stable
Electromagnetic current meter	376	Determination of water velocity based on the principle that a...	Concept	stable
Stream index-velocity rating	377	Computation of stream discharge based on a relation between s...	Concept	stable
Acoustic doppler velocity meter (ADVM)	378	Determination of water velocity by using the Doppler principl...	Concept	stable
inapplicable	inapplicable	None of the codes in the table are applicable in the context ...	Concept	stable
unknown	unknown	The measurement/observing method is unknown.	Concept	stable