Description
Return benthic density only when area is known and positive.
Aquatic sampling expands observed counts using supplied area, filtered volume or processed fractions. Net efficiency, slip and grain-class boundaries affect that accounting. A scaled count or one-point class assignment does not establish true population abundance, detection probability or a universal substrate classification.
Return benthic density only when area is known and positive.
When to use this tool
Use Benthic Count Unknown Area Flag when checking the stated aquatic sampling-volume, density or class-boundary convention.
How to use the tool and how it works
- Enter count, area, areaKnown. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read densityDefined, density. Inspect densityDefined before interpreting the associated values.
Return benthic density only when area is known and positive. Require nonnegative whole count and area >= 0; densityDefined = areaKnown and area>0, otherwise density is zero placeholder.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| count | Supplied observation count on the stated sampling basis. | Required. Safe integer; minimum 0. |
| area | Area in the common squared-length unit specified above. | Required. Finite number; minimum 0. |
| areaKnown | Area Known | Required. Boolean. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| densityDefined | Density Defined | Required. Boolean. |
| density | Count/area only when areaKnown and area>0; zero placeholder otherwise. | Required. Finite number. |
{
"input": {
"count": 20,
"area": 0,
"areaKnown": false
},
"output": {
"densityDefined": false,
"density": 0
}
}Limitations and assumptions
- A false flag with zero density is not evidence of zero organisms; area and count records are not verified.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Use verified field methods, calibrated sampling efficiency and an appropriate statistical or classification scheme for abundance and ecological assessment.
References
Similar or alternative tools
- Benthic Sample Sieved Fraction Area
Return area density after a supplied processed fraction.
- Plankton Count Volume Factor
Scale an observed plankton count to a reference volume.