GEE-Based monitoring method of key management nodes in cotton production

Figures & data

Table 1. Data Sources for each section.

Section	Methods	Use	Data Source	Date Range
Cotton Classification	CART	Train	Manually surveyed and labeled	2019
	SVM	Test	Sentinel-1 and Sentinel-2
	RF	Predict	Sentinel-1 and Sentinel-2	2019, 2020
Cultivation process	CART	Train	Manually surveyed and labeled	2021
	SVM	Test	Sentinel-1 and Sentinel-2
	RF	Predict	Sentinel-1 and Sentinel-2	2020, 2021
Abandoned cropland detection	Otsu	Detect	Sentinel-2	2019, 2020

Figure 1. Technical route (the model classifier train is a reused part.).

Figure 2. Overview of the study area and distribution of some samples.

Figure 3. Data set area distribution.

Figure 4. Example of the image covered by plastic film on May 6, 2021.

Figure 5 Prediction result combination diagrams.

Figure 6. Monthly changes in different categories.

Table 2. Model verification results for classification.

	Overall Accuracy	User's Accuracy			Producer's Accuracy			kappa
		Cotton	Water	Other	Cotton	Water	Other
SVM	91.92%	89.93%	93.09%	93.02%	98.25%	94.25%	83.25%	0.879
CART	93.92%	94.46%	96.70%	90.71%	93.75%	95.25%	92.75%	0.908
Random Forest	96.50%	95.86%	96.09%	97.63%	98.50%	98.25%	92.75%	0.947

Figure 7. Detailed display of classification results.

Table 3. Model verification results for the cultivation process.

	Overall Accuracy	User's Accuracy		Producer's Accuracy		kappa
		Without	With	Without	With
SVM	82.76%	84.55%	81.15%	80.17%	85.34%	0.655
CART	87.07%	85.83%	88.39%	88.79%	85.34%	0.741
Random Forest	86.64%	87.61%	85.71%	85.34%	87.93%	0.733

Figure 8. Cultivation progress at different times based on different models.

Table 4. Cultivation progress monitored by different models.

Date Range	1-Apr: 10-Apr		11-Apr: 20-Apr		21-Apr: 30-Apr		1-May: 10-May
Model	2020	2021	2020	2021	2020	2021	2020	2021
SVM	10.89%	7.92%	63.59%	44.81%	63.59%	64.19%	69.36%	70.51%
CART	5.56%	1.64%	52.79%	25.15%	52.79%	45.36%	62.39%	69.67%
Random Forest	2.57%	0.48%	50.84%	20.93%	50.84%	40.41%	56.43%	64.60%

Figure 9. Statistics of cultivation progress monitored by each model.

Figure 10. Changes in the detection results of abandoned cropland.

Figure 11. Statistics of abandoned cropland detection results.

Data availability

Data available on request from the authors.