Abstract
Several of the projects in the AgRISTARS program require crop phenology information, including classification, acreage and yield estimation, and detection of episodal events. This study evaluates several crop calendar estimation techniques for their potential use in the program. The techniques, although generic in approach, were developed and tested on spring wheat data collected in 1978. There are three basic approaches to crop stage estimation: historical averages for an area (normal crop calendars), agrometeorological modeling of known crop-weather relationships agrometeorological (agromet) crop calendars, and interpretation of spectral signatures (spectral crop calendars). In all, 10 combinations of planting and biostage estimation models were evaluated. Dates of stage occurrence are estimated with biases between -4 and +4 days while root mean square errors range from 10 to 15 days. Results are inconclusive as to the superiority of any of the models and further evaluation of the models with the 1979 data set is recommended.
Abstract from the paper’s OpenAlex record, shown for indexing and research. Copyright remains with the authors or the publisher.
The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.
Claims 4
Claim · model-written summary
Crop stage dates were estimated with biases between -4 and +4 days.
- Taxon
- spring wheat
Triticum aestivume1 - Outcome
- biasese0
- Value
- between -4 and +4 dayse0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Dates of stage occurrence are estimated with biases between -4 and +4 days”
e1“developed and tested on spring wheat data collected in 1978”
Claim · model-written summary
Root mean square errors ranged from 10 to 15 days.
- Taxon
- spring wheatTriticum aestivume1
- Outcome
- root mean square errorse0
- Value
- 10 to 15 dayse0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“root mean square errors range from 10 to 15 days”
e1“developed and tested on spring wheat data collected in 1978”
Claim · model-written summary
Results were inconclusive about superiority among the crop stage models.
- Taxon
- spring wheatTriticum aestivume1
- Outcome
- superioritye0
- Qualifier
- inconclusivee0
- Comparator
- modelse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Results are inconclusive as to the superiority of any of the models”
e1“developed and tested on spring wheat data collected in 1978”
Claim · model-written summary
The authors recommend further model evaluation using the 1979 data set.
- Taxon
- spring wheatTriticum aestivume1
- Outcome
- further evaluation of the models with the 1979 data sete0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“further evaluation of the models with the 1979 data set is recommended”
e1“developed and tested on spring wheat data collected in 1978”