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Sugarcane Crop Type Discrimination and Area Mapping at Field Scale Using Sentinel Images and Machine Learning Methods

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Crop mapping and acreage estimation are the simplest yet the most critical issues in agriculture. Remote sensing technology has been extensively used in the past few decades for executing these tasks. The objective of this study is to map sugarcane fields at a catchment level and segregate the plant and ratoon fields using the freely available Sentinel-1 and Sentinel-2 data. The study is carried out at the Kisan Sahkar Chini Mill catchment in the Saharanpur district of Uttar Pradesh. The objective was achieved by a two-step process where firstly the sugarcane fields are identified using Random Forest and SVM classifiers over temporal optical and microwave images. The most accurate result is used as a crop mask to separate the plant and ratoon fields. This was achieved by attempting a phenology-based classification and spectral-based classification. The results revealed that temporal Sentinel-2 data are highly competent in classifying sugarcane at the farm level and segregating the plant and ratoon fields. The sugarcane crop mask was created with a kappa coefficient of 0.95 using the SVM classifier, and the plant and ratoon fields were discriminated using the Random Forest classifier with a kappa coefficient of 0.81. The sugarcane crop area was estimated to be approximately 535 acres of plant crop and 560 acres of the ratoon crop while the mill estimate was 520 acres and 540 acres, respectively. The results showed that Sentinel-2 has promising capabilities and is a convenient asset in delineating small-sized farms and classifying sugarcane and its crop types.
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RESEARCH ARTICLE
Sugarcane Crop Type Discrimination and Area Mapping at Field Scale
Using Sentinel Images and Machine Learning Methods
Ashmitha Nihar
1
N. R. Patel
1
Shweta Pokhariyal
1
Abhishek Danodia
1
Received: 30 September 2020 / Accepted: 12 October 2021
ÓIndian Society of Remote Sensing 2021
Abstract
Crop mapping and acreage estimation are the simplest yet the most critical issues in agriculture. Remote sensing tech-
nology has been extensively used in the past few decades for executing these tasks. The objective of this study is to map
sugarcane fields at a catchment level and segregate the plant and ratoon fields using the freely available Sentinel-1 and
Sentinel-2 data. The study is carried out at the Kisan Sahkar Chini Mill catchment in the Saharanpur district of Uttar
Pradesh. The objective was achieved by a two-step process where firstly the sugarcane fields are identified using Random
Forest and SVM classifiers over temporal optical and microwave images. The most accurate result is used as a crop mask to
separate the plant and ratoon fields. This was achieved by attempting a phenology based classification and spectral based
classification. The results revealed that temporal Sentinel-2 data are highly competent in classifying sugarcane at farm level
and segregating the plant and ratoon fields. The sugarcane crop mask was created with a kappa coefficient of 0.95 using the
SVM classifier, and the plant and ratoon fields were discriminated using the Random Forest classifier with a kappa
coefficient of 0.81. The sugarcane crop area was estimated to be approximately 535 acres of plant crop and 560 acres of the
ratoon crop while the mill estimate was 520 acres and 540 acres, respectively. The results showed that Sentinel-2 has
promising capabilities and is a convenient asset in delineating small-sized farms and classifying sugarcane and its crop
types.
Keywords Sugarcane mapping Random forest SVM Ratoon Sentinel Machine learning Farm scale
Remote sensing Object and Pixel based
Introduction
Agriculture is the chief source of social well-being in most
parts of the World. In India, agriculture’s importance is
hardly overstated, as it plays an enormous role in the
economy. The necessity and significance of timely and
reliable estimation of crop acreage and production for the
use of decision-makers, including but not limited to the
producers, processors, managers and the government is
widely acknowledged (Nihar et al., 2019). Misleading
production estimates give way to flawed policies regarding
imports, exports and stockholding of agriculture-based
commodities. It leads to problems for farmers, traders and
consumers through market distortion. Hence the colossal
risks and drawbacks of unreliable crop area and production
estimates are self-explanatory for India, a country that
caters more than 1.3 billion people.
Sugarcane (Saccharum officinarum), a perennial cash
crop of the grass family Poaceae, is one of the widely
grown crops that contribute significantly to the national
exchequer and employs over a million people in India. The
crop is one of India’s top priority commercial crops, and
yet the official estimations frequently vary widely from
those of the trade and industry. While the sugarcane crop
&Ashmitha Nihar
ashmitha.sab@gmail.com
N. R. Patel
nrpatel@iirs.gov.in
Shweta Pokhariyal
shwetapokhariyal9@gmail.com
Abhishek Danodia
abhidanodia@iirs.gov.in
1
Agriculture and Soils Department, Indian Institute of Remote
Sensing, ISRO, 4, Kalidas Road,
Dehradun 248001, Uttarakhand, India
123
Journal of the Indian Society of Remote Sensing
https://doi.org/10.1007/s12524-021-01444-0(0123456789().,-volV)(0123456789().,-volV)
acreage information at a regional scale is vital in terms of
trade decisions, insurance and policy-making, they are also
crucial at a field level to the crushing mills in terms of
budget, crop plan, commercial strategy, harvest scheduling,
field expansion or renewal.
Crop acreage estimation is cumbersome when carried
out manually because of the vast land size, which is easily
overcome by satellite imagery. Remote Sensing (RS) is a
powerful and compelling technology for crop inventory
mapping, acreage estimation, monitoring, phenology
extraction and production estimation of crops with rea-
sonable accuracy depending on sensor characteristics
(Patel et al., 2006). Applications of RS technology for the
agricultural industry has attracted research from several
scholars worldwide. It is now being normalized to use RS
to understand and answer many of the spatial queries
regarding agriculture. Classification of crops to estimate
their area and extent is among the most common applica-
tions of satellite-based RS. Crop inventory mapping rests
as the basis for other studies like yield estimation,
parameter retrieval and the crop response to the biotic and
abiotic factors in its environment. By appropriate selection
of spatial and spectral resolution and processing tech-
niques, satisfying results can be achieved by RS technology
for the use of sugarcane crop (Abdel-Rahman & Ahmed,
2008).
Several different approaches have come in to place to
map crops accurately. A plethora of studies have been
performed to evaluate different types of data such as
optical, microwave and hyperspectral data to map sugar-
cane. While the optical data provide information about the
pigments, cellular content and structure, microwave data
are more responsive to the crop’s geometry and dielectric
properties. Pandey et al. (2019) estimated the sugarcane
crop acreage using Landsat and IRS ResourceSat datasets
with the help of extensive field sampling and illustrated the
importance of the sensor’s spatial resolution map sugar-
cane at mill catchment level. Singla et al. (2018), proposed
that the temporal profile of Normalized Difference Vege-
tation Index (NDVI) can be efficiently used to discriminate
the sugarcane crop types at any given scale. High-resolu-
tion LISS – IV data is often explored to study sugarcane
mapping in India (Singh et al., 2020; Verma et al., 2017).
The synergistic use of optical and microwave datasets to
map sugarcane is also being explored recently (Jiang et al.,
2019; Wang et al., 2020).
Several studies have reported satisfying results for the
application of satellite imagery in mapping sugarcane.
However, minimal research has been extended into map-
ping the types of sugarcane, namely the plant and the
ratoon. Ratooning is the practice of regrowing sugarcane
from the existing roots of the crop after harvesting. While
the planted crop grows over twelve months, the ratoon crop
generally takes only nine to ten months. The ratoon crops
grow faster as they already have a well-established root
system. The plant crops provide higher sugar recovery rates
and have a higher number of tillers. The classification of
sugarcane and these crop types is performed in this study
using the two major algorithms Support Vector Machine
(SVM) and Random Forest (RF).
Recently, the advanced classifiers SVM and RF have
drawn much attention from the scientific community due to
their high accuracy (Mather and Tso, 2009). SVM stands
robust and consistent regardless of high data dimension-
ality, data imbalance and limited training data (Sheykh-
mousa et al., 2019; Ustuner et al., 2016), while RF is more
common due to its easy implementation, speed and
insensitivity to overfitting (Belgiu & Dra
˘gu, 2016; Moun-
trakis et al., 2011). It is also reported that in the case of
lower resolution images, RF performs consistently better
than SVM. However, SVM outperforms RF while classi-
fying data containing a higher number of features
(Sheykhmousa et al., 2020).
With the help of the two competent classifiers, mapping
of sugarcane crop types at a farm level is performed over
the freely available high-resolution Sentinel-1 and Sen-
tinel-2 data. This study is an attempt to comparatively
assess the viability and efficiency of the two characteris-
tically different datasets to map sugarcane at field level and
discriminate the crop type in a study area with an average
field size of around 0.4 acres.
Materials and Methods
Study Area
The Kisan Sahkari Chini Mill (KSCM) Catchment located
in the town of Nanauta in the district of Saharanpur, Uttar
Pradesh was chosen as the area of interest for this study.
The districts of Uttarakhand, namely Dehradun and
Haridwar neighbour Saharanpur by the North and the West,
respectively; the Karnal and Ambala districts of Haryana
border Saharanpur by the East and the District of Muzaf-
farnagar of Uttar Pradesh on the South. The catchment area
extends between 29.62 °N and 29.83 °N latitude, and
between 77.20 °E and 77.54 °E longitude. The mill
catchment contains sugarcane fields from around 165 vil-
lages covering a total area of over 460 square kilometres
with an average sugarcane field size being 0.4 acres. The
KSC Mill currently has a cane crushing capacity of 5000
tons per day, with an average sugarcane yield of 833
quintals/hectare and average sugar return of 8.45%.
The heart of the economy of this district is agriculture
with sugarcane as the principal commercial crop. Rice,
wheat, mustard, potato and tomato are among the other
Journal of the Indian Society of Remote Sensing
123
crops grown in the area. Mango orchards and Poplar
plantations are also commonly found here. The Saharanpur
district experiences a humid subtropical climate with
annual precipitation ranging from 750 to 1200 mm and
temperature ranging from 4 °C in winters up to 40 °Cin
summers. Figure 1shows a false colour composite image
of the KSCM catchment.
Data Used
The European Union’s Radar imaging Sentinel-1A (C-
Band) datasets and the optical Earth observation datasets of
the twin satellites Sentinel-2A and Sentinel-2B were used
in this study for mapping sugarcane in the catchment area.
The Sentinel-2 mission provides optical images at a tem-
poral resolution of 5 days with high resolution up to 10 m
offering an extensive range of crop monitoring applica-
tions. The bottom of atmosphere reflectance (Level 2A)
products (available globally since 2018) were collected for
the period January 2019 to January 2020 (77 images) to
monitor and extract the field parcel’s phenology in the
study area. The study area lies on the junction of two image
tiles, and hence, all the images had to be mosaicked. Out of
this dataset, one cloud-free image each from April, May,
October and November was chosen for the spectral
classification. Table 1shows a list of all the satellite ima-
gery used in this study.
Four Sentinel-1A SAR images from April, June, August
and October were collected for this study to map sugarcane
field parcels. These images were downloaded as Level -1
Ground Range Detected (GRD) products obtained by
Interferometric Wide (IW) swath mode. The four images
were pre-processed to obtain the VV and VH polarized
backscatter images and stacked.
Around 250 Ground Truth (GT) Points were collected in
the last week of September 2019. The sugarcane crop type
and approximate dates of sowing and harvest were also
collected along with other land-use information. These GT
points were used to train and validate the classifiers in an
80:20 split, respectively.
Methodology
This study aims to map the sugarcane field parcels in the
KSCM catchment and classify the sugarcane plant and
ratoon crops using machine learning methods and estimate
their area. This is achieved by using a two-step process
where the sugarcane crop field parcels are separated from
the other land-use classes first, and the fields are then
segregated as plant or ratoon. Temporal microwave and
optical data were used for this purpose. Both object-based
Fig. 1 False Colour Composite of Study Area
Journal of the Indian Society of Remote Sensing
123
and pixel-based approaches were performed to map the
field parcels. The overall flow-chart and steps involved in
discrimination of sugarcane crop types in the mill catch-
ment area and for one specific village (Gudamb) are pre-
sented in Fig. 2.
Sugarcane Field Mapping
Mapping of the sugarcane crop fields was performed by
object-based and pixel-based classifications using the SVM
and RF classifiers. Image segmentation was done on a
cloud-free optical image of October 2019, resulting in
several objects or segments. The image objects layer was
used to support the object-based classification for both
optical and SAR images. Temporal Image Composites
were prepared from the four SAR images and four optical
images using the data listed in Table 1. The classification
was carried out to separate the major classes such as set-
tlement, water-body, sugarcane, paddy, vegetables, mango
and poplar plantations. The different types of classification
carried out were: (1) object-based classification on single
date optical image (2) object-based classification on the
temporal optical image, (3) object-based classification on
temporal SAR image and (4) pixel-based classification
Table 1 Optical and SAR
imagery used in this study Classification methods Sensor Dates
SAR temporal Sentinel-1 28-04-2019; 03-06-2019; 14-08-2019; 17-10-2019
Phenology retrieval Sentinel-2 January 2019 – January 2020 (77 images)
Optical temporal Sentinel-2 25-04-2019; 30-05-2019; 17-10-2019; 16-11-2019
Optical single date Sentinel-2 17-10-2019
Image Segmentation Sentinel-2 17-10-2019
Fig. 2 Flow-Chart Methodology for field-scale sugarcane crop type discrimination and area mapping
Journal of the Indian Society of Remote Sensing
123
over the temporal optical image. The points from the GT
campaign were used as training points for the classifiers.
The GT points were split into 80% and 20% for training
and evaluation, respectively. The sugarcane crop mask is
obtained from the best performing classifier and dataset
combination after eliminating the other land-use classes.
Sugarcane Plant Versus Ratoon Discrimination
After separation of the sugarcane field parcels from the
other pixels, they are categorized into plant and ratoon
crops using the SVM and RF classifiers. The plant versus
ratoon segregation was performed using (1) the temporal
optical image and (2) an image stack of vegetation phe-
nology parameters. Vegetation phenology refers to sea-
sonal changes or life events in a crop’s growing period.
Phenology metrics for the sugarcane crop were derived
from the TIMESAT software using temporal NDVI data
computed from Sentinel-2 images for the period January
2019 to January 2020. The TIMESAT program generates
smooth functions to extract phenological parameters. The
curve fitting processes are based on least-square fit where
the local functions are fused to form Global functions that
describe NDVI over the full seasonal cycle. This software
provides an interface to fit a time series of Vegetation
Indices data into nonlinear mathematical functions (Ek-
lundh & Jo
¨nsson, 2017). For this study, the Asymmetric
Gaussian model was fit into a time series of NDVI images.
The temporal resolution was reduced from 5 to 15 days by
taking a maximum NDVI pixel composite to avoid cloud
interference in the optical data. The phenological metrics
namely Start of Season (SOS), End of Season (EOS),
Length of the growing period or season (LOS), Maximum
NDVI value during the growing period, Time of occur-
rence of Maximum value, Value of NDVI at SOS and EOS
and Amplitude were extracted from the NDVI data. The
eight parameters extracted from TIMESAT were written
into images, and a composite image was made for the
sugarcane crop mask created earlier. The SOS and EOS
extracted from the software showed a difference of up to
two weeks compared to GT. The phenology metrics images
extracted and the optical temporal image used earlier were
classified to label the fields as plant or ratoon using the GT
points. The GT points were again split into 80% and 20%
for training and testing, respectively. Ultimately, the sug-
arcane fields were mapped and classified into the plant or
ratoon crops, and their acreage was estimated. The acreage
was compared with the sugarcane crop area dataset avail-
able from the mill.
Results and Discussion
The present study was undertaken to classify sugarcane
crop fields in the KSCM mill catchment area in Uttar
Pradesh. The discrimination of the plant and ratoon crop
using satellite data was also achieved in a two-step process.
First, the sugarcane pixels are identified, and secondly, they
are classified as ratoon or plant. Table 2shows a compar-
ison of the accuracies of the different classifiers over dif-
ferent datasets and the best outcome is highlighted in bold.
It is seen that the optical datasets offered better results than
the SAR data regardless of the classifier used. The SVM
classifier on the optical multi-temporal dataset gave the
highest accuracy of 95.9% and a Kappa coefficient of 0.95.
Figure 3shows the results for the extraction of sugarcane
crop mask using the SVM classifier over temporal optical
data.
It is also seen that contrary to many other studies that
claim object-based classification is better than the pixel-
based classification (Makinde et al., 2016; Whiteside et al.,
2011), the pixel-based classification performed better in
classifying the small sugarcane fields. This is because of
the scale of objects being mapped and the resolution of the
data used. Since the field parcels in this region are rela-
tively small and the marginal pixels are influenced by the
neighbouring land-use classes, only a few pure pixels in
the farm’s interior represent the actual spectral characters
of the sugarcane crop. While the pixel-based classification
is spot on solely based on every individual pixel’s spectral
characters, the object-based classification takes the average
spectral response of a group of pixels considered an object
based on their visual qualities as shape, size and colour. .
As explained by Cai and Liu (2013), the most meaningful
objects might have fewer pixels. Thus the accuracy of the
classifiers based on objects is compromised. The Sentinel-2
dataset still stands competent in pixel-based classification
for mapping small farms. The results are also comparable
to the sugarcane mapping using Sentinel-2 data carried out
by Wang et al. (2019). With higher resolution datasets, the
object-based classification may work better to delineate the
small farms. The sugarcane crop mask was extracted from
the SVM classifier results, and the mask was used to further
classify the fields as plant or ratoon.
Table 3shows that the RF classifier’s performance over
the temporal optical images gave the best results (high-
lighted in bold) for segregation of plant and ratoon fields. It
was noticed that the phenology-based classification did not
provide expected results in terms of classifying plant and
ratoon crops.
Figure 4shows that the Random Forest classifier over
the optical dataset shows a very satisfying classification
with significantly less noisy pixels. The field boundaries
Journal of the Indian Society of Remote Sensing
123
Table 2 Comparison of classification accuracies of sugarcane in Nanauta mill catchment
Image input Type of
classification
Classifier Producer accuracy
(%)
User’s accuracy
(%)
Overall accuracy
(%)
Kappa
coefficient
Sentinel-1 Multi-
temporal
Object-based RF 86.21 75.76 70.89 0.66
SVM 82.76 80.00 71.42 0.66
Sentinel-2 Single date RF 72.41 70.00 79.89 0.76
SVM 65.52 67.86 76.71 0.73
Sentinel-2 Multi-
temporal
RF 86.21 75.76 86.77 0.84
SVM 89.66 78.79 87.30 0.85
Sentinel-2 Multi-
temporal
Pixel-based RF 94.89 91.69 93.44 0.92
SVM 97.53 93.55 95.91 0.95
Fig. 3 Optical Temporal Classification using SVM classifier
Table 3 Comparison of classification accuracies to discriminate sugarcane plant and ratoon crop type
Image input Classifier Average producer accuracy
(%)
Average user’s accuracy
(%)
Overall accuracy
(%)
Kappa
coefficient
Phenology parameters RF 75.52 75.29 76.63 0.50
SVM 77.19 77.75 78.84 0.54
Sentinel-2 multi-
temporal
RF 90.55 90.71 90.75 0.81
SVM 84.38 83.54 83.47 0.73
Journal of the Indian Society of Remote Sensing
123
are also prominently visible. The phenology-based classi-
fication’s lower accuracy stems from the staggered SOS
and EOS dates in the catchment area. Phenology is cal-
culated from images spanning over the entire year, pro-
viding a wide range for SOS and EOS dates. This extensive
range of SOS and EOS could overlap for the plant and
ratoon crops, thus confusing the classifier. Meanwhile, the
ratoon crops having a much voluminous canopy and better
vigour are spectrally distinguishable from the plant crops
using the optical satellite images. Another factor that plays
Fig. 4 Plant and Ratoon discrimination using RF and SVM classifiers over optical data and phenology parameters
Fig. 5 A comparison of Plant vs Ratoon classification against the GPS survey in the Gudamb village, KSCM catchment
Journal of the Indian Society of Remote Sensing
123
an important role is the inevitability of clouds in optical
data. Unlike spectral image-based classification, the cloud
cannot be eliminated entirely from the time series of
optical images while extracting phenology. The spectral
image-based classification thus shows higher accuracy. The
SVM and RF demonstrated outstanding performance in
classifying the sugarcane crop types as discussed by
Everingham et al., (2007). Figure 5compares the two
classifiers over the Gudamb village in the mill catchment
area against the GPS based field survey data.
From the final classified image using the optical images,
the plant and ratoon fields’ area in the catchment area were
computed. According to the data collected from the KSC
mill’s GPS survey, the catchment area had around 520
acres and 540 acres of plant and ratoon crops, respectively.
The classification results showed a slightly higher estima-
tion of approximately 535 acres of sugarcane plant crop
and 560 acres of the ratoon crop.
Conclusions
Sentinel-2 images showed promising capabilities for field-
level classification as well as discrimination between sug-
arcane plant and ratoon crops in the mill catchments with
the help of ground truth points. It is desirable to use pixel-
based classification to delineate the small field parcels
using Sentinel data. The sugarcane fields were isolated
from other land cover classes with an overall accuracy of
95.91% and 0.95 kappa coefficient using the SVM classi-
fier. The plants and ratoon fields were separated with an
accuracy of 90.75% and 0.81 kappa coefficient using the
Random Forest classifier. The sugarcane plant and ratoon
crops were estimated to cover around 520 acres and 540
acres, respectively, of the catchment area. Sentinel-2 data
delivered convincing results with SVM and RF classifiers
to delineate small-sized farms and map the different crop
types. Outcomes of this study suggest that the Sentinel-2
datasets can be exploited conveniently in crop mapping and
monitoring at the farm scale.
Acknowledgements Authors sincerely express their gratitude to
General Manager, Kisan Sahkari Chini Mills Ltd (KSCM) and Mr.
Varshney, IT cell, KSCM for providing necessary information and
GPS based field survey of sugarcane crop besides other logistic
support. We are also thankful to Director, IIRS for providing neces-
sary facilities and encouragement to carry out research for farmer-
centric applications.
Declarations
Conflict of interest The authors declare no conflict of interest.
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... Subsequent studies (Miglani et al. 2008;Dheeravath et al. 2010;Vikesh et al. 2010;Misra et al. 2012;Singla et al. 2018aSingla et al. , 2018bDubey et al. 2018;Murugan and Singh 2018;Mandal et al. 2019;Sharma et al. 2019;Pandey et al. 2019;Kumar et al. 2022;Tripathy et al. 2023) have utilized RS data for various applications in sugarcane, including classification, mapping, yield, and acreage estimation. However, these studies reported relatively lower accuracy compared to AI-powered RS studies (Pandit et al. 2006;Yedage et al. 2013;Misra et al. 2014;Verma et al. 2016Verma et al. , 2017Kumar et al. 2017;Singh et al. 2020;Singla et al. 2018cSingla et al. , 2020Virnodkar et al. 2021aVirnodkar et al. , 2022Kritika et al. 2021;Bhosle and Musande 2022;Nihar et al. 2022;Mishra et al. 2023). As evident from the literature, AI-based RS applications have notably enhanced sugarcane agriculture, optimizing crop management and productivity (Virnodkar et al. 2020a;. ...
... SVM, applied to various satellite datasets {sentinel-1 synthetic aperture radar (SAR), LANDSAT-8 OLI, LISS-IV, sentinel-2}, showed overall accuracies ranging from 81.86-93.50% (Mishra et al. 2023;Verma et al. 2016;Kumar et al. 2017;Virnodkar et al. 2021a;Nihar et al. 2022). Interestingly, the integration of a 2D CNN model with SVM on Sentinel-2 data slightly increased accuracy to 87.70% (Virnodkar et al. 2022). ...
... In a recent study, Random Forest (RF) showed superior performance with 97% accuracy in discriminating between types of sugarcane using spectral data, highlighting the efficacy of ML in handling binary classification tasks based on remotely sensed data (Singla et al. 2021). The RF technique demonstrated impressive results (93.77% OA) on Sentinel-1 SAR data (Mishra et al. 2023) and Sentinel-2 multi-temporal data with 93.44% OA (Nihar et al. 2022) for sugarcane classification. However, the accuracy for discriminating sugarcane plant and ratoon plant was slightly lower at 90.75% (Nihar et al. 2022). ...
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Sugarcane holds a critical position in global agriculture, serving as a basis for the sugar and bioenergy sectors. The integration of remote sensing technologies and sophisticated machine learning approaches and related models has revolutionized sugarcane research. These tools offer efficient, noninvasive, and large-scale assessment methods. This review highlights the utilization of satellite imagery and sensor data, encompassing RGB, multispectral, hyperspectral, and unmanned aerial vehicles (UAVs) in sugarcane agriculture. It addresses crop identification, pest and disease management, yield and acreage estimation, modeling, phenotypic measurement, and their impact on empowering farmers with insights for optimal irrigation, fertilizer application, and overall crop management. These advancements significantly increase productivity and foster environmental sustainability. The review had dual aims: (1) consolidate RS data applications in India’s sugarcane research and development, and (2) examine the pros and cons of RS and AI methods in sugarcane farming. The review employed prominent bibliographic databases—google scholar, scopus, researchgate, and web of science—along with pertinent research articles on RS and AI applications in sugarcane, and comprehensive data on sensors and UAVs retrieved from these databases. The study concludes that AI-driven crop RS stands as an effective method for monitoring and managing sugarcane, contributing significantly to improving yield and quality, while simultaneously offering substantial benefits in social, economic, and environmental realms. However, challenges in the sugar industry, such as adapting technology, high initial costs, climate impact, communication, policy, and regulation, must be addressed.
... Unlike traditional yield estimation methods, GPS-based yield mapping provides an objective measurement of the yield, reducing the potential for human error and inconsistencies. This leads to more accurate yield estimates, which can be used to optimize the potato harvesting process and improve overall productivity [129]. In addition to improving the efficiency of the potato harvesting process, GPS-based yield mapping can also be used to monitor crop performance over time. ...
... Collecting and managing large amounts of yield data can be challenging, especially for farmers with limited technical expertise. The cost of GPS-based yield mapping systems can be prohibitive for some farmers, particularly small-scale farmers [129]. ...
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... Nihar et al. [43] combined Sentinel-1 and Sentinel-2 either to classify the sugarcane based on random forest and SVM classifiers. The 0.95 kappa coefficient of sugarcane classification was claimed from the SVM classifier. ...
... Out of the total studies included in the sub-category of crop classification (Table 7), maximum studies were based on optical dataset [40][41][42][43][44][45][46][47][48][49][50], while six studies [51][52][53][54][55][56] utilized the capability of both optical and microwave remote sensing to classify crops, particularly during Kharif season. Refs. ...
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In India, agriculture serves as the backbone of the economy, and is a primary source of employment. Despite the setbacks caused by the COVID-19 pandemic, the agriculture and allied sectors in India exhibited resilience, registered a growth of 3.4% during 2020–2121, even as the overall economic growth declined by 7.2% during the same period. The improvement of the agriculture sector holds paramount importance in sustaining the increasing population and safeguarding food security. Consequently, researchers worldwide have been concentrating on digitally transforming agriculture by leveraging advanced technologies to establish smart, sustainable, and lucrative farming systems. The advancement in remote sensing (RS) and machine learning (ML) has proven beneficial for farmers and policymakers in minimizing crop losses and optimizing resource utilization through valuable crop insights. In this paper, we present a comprehensive review of studies dedicated to the application of RS and ML in addressing agriculture-related challenges in India. We conducted a systematic literature review following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines and evaluated research articles published from 2015 to 2022. The objective of this study is to shed light on the application of both RS and ML technique across key agricultural domains, encompassing “crop management”, “soil management”, and “water management, ultimately leading to their improvement. This study primarily focuses on assessing the current status of using intelligent geospatial data analytics in Indian agriculture. Majority of the studies were carried out in the crop management category, where the deployment of various RS sensors led yielded substantial improvements in agricultural monitoring. The integration of remote sensing technology and machine learning techniques can enable an intelligent approach to agricultural monitoring, thereby providing valuable recommendations and insights for effective agricultural management.
... In the field of crop mapping, data fusion includes the fusion of multi-sensor images from the same temporal window da Silva Junior et al. 2020), multi-sensor spatial overlap for large-scale mapping needs, the fusion of optical and radar sensor data often with spectral indices Tian2019, Jin2019, (Tian et al. 2019;Zhenong et al. 2019;Amani et al. 2020;Qiu et al. 2022;Nihar et al. 2022;Chabalala, Adam, and Adem Ali 2022;Diem et al. 2022), and to some extent the combination of multi-sensor optical Paludo et al. 2020;Htitiou et al. 2021b;Yan et al. 2021Rehman et al. 2023, or SAR data only Mandal et al. 2018. Recently, Qiu et al. (2022 developed a robust algorithm that uses multi-sensor time-series data fusion for mapping cultivated fields at a 20 resolution at the national scale in China. ...
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The ever-increasing global population presents a looming threat to food production. To meet growing food demands while minimizing negative impacts on water and soil, agricultural practices must be altered. To make informed decisions, decision-makers require timely, accurate, and efficient crop maps. Remote sensing-based crop mapping faces numerous challenges. However, recent years have seen substantial advances in crop mapping through the use of big data, multi-sensor imagery, the democratization of remote sensing data, and the success of deep learning algorithms. This systematic literature review provides an overview of the history and evolution of crop mapping using remote sensing techniques. It also discusses the latest scientific advances in the field of crop mapping, which involve the use of machine and deep learning models. The review protocol involved the analysis of 386 peer-reviewed publications. The results of the analysis show that areas such as crop rotation mapping, double cropping, and early crop mapping require further exploration. The use of LiDAR as a tool for crop mapping also needs more attention, and hierarchical crop mapping is recommended. This review provides a comprehensive framework for future researchers interested in accurate large-scale crop mapping from multi-source image data and machine and deep learning techniques.
... We can train an ML algorithm on a heterogenous and "messy" dataset to learn meaningful and non-duplicative patterns to solve a task automatically, accurately, and unbiasedly. Some applications of ML for sugarcane research and development available from earlier independent studies include predicting or forecasting chlorophyll content (Narmilan et al., 2022), standard morphophysiological variables , production of biomass , and classify cultivation (Nihar et al., 2022). We developed a new pathway by mapping spectral features to°B rix and Purity; hence we can fulfill a gap in analyzing qualitative yield while improving the addressability of a UAV for scalable aerial remote sensing. ...
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Predicting sugarcane yield by quality allows stakeholders from research centers to industries to decide on the precise time and place to harvest a product on the field; hence, it can streamline workflow while leveling up the cost-effectiveness of full-scale production. °Brix and Purity can offer significant and reliable indicators of high-quality raw material for industrial processing for food and fuel. However, their analysis in a relevant laboratory can be costly, time-consuming, and not scalable. We, therefore, analyzed whether merging multispectral images and machine learning (ML) algorithms can develop a non-invasive, predictive framework to map canopy reflectance to °Brix and Purity. We acquired multispectral images data of a sugarcane-producing area via unmanned aerial vehicle (UAV) while determining °Brix and analytical Purity from juice in a routine laboratory. We then tested a suite of ML algorithms, namely multiple linear regression (MLR), random forest (RF), decision tree (DT), and support vector machine (SVM) for adequacy and complexity in predicting °Brix and Purity upon single spectral bands, vegetation indices (VIs), and growing degree days (GDD). We obtained evidence for biophysical functions accurately predicting °Brix and Purity. Those can bring at least 80% of adequacy to the modeling. Therefore, our study represents progress in assessing and monitoring sugarcane on an industrial scale. Our insights can offer stakeholders possibilities to develop prescriptive harvesting and resource-effective, high-performance manufacturing lines for by-products.
... Sugarcane mills have used different techniques to estimate sugarcane crop yield since the establishment of the commercial cultivation of sugarcane. A few sugar mills have begun the process of computing the acreage through manual surveys of the field perimeters using GPS technology for their mill catchment, promoting field-based studies for sugarcane discrimination (Nihar et al., 2022;Singh et al., 2020). The yield estimates are still based on the traditional, destructive crop-cutting experiments and manual scouting. ...
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Sugarcane (Saccharum officinarum) is a major cash crop in India that needs to be monitored cautiously as it contributes significantly to the national exchequer and provides employment to over a million people mainly through sugar and renewable bioenergy production. The objective of this study is to predict the regional sugarcane crop yield for the Uttar Pradesh (UP) province using analysis-ready moderate-resolution satellite images. The four machine learning regression algorithms, namely support vector regression (SVR), gradient boosting regression (GBR), eXtreme gradient boosting regression (XGB), and random forest regression (RF), were used to train and predict the district-wise sugarcane yield in UP. Standard MODIS data products such as leaf area index (LAI), fraction of photosynthetically active radiation (FPAR), normalized difference vegetation index (NDVI), enhanced vegetation index (EVI), evapotranspiration (ET), potential evapotranspiration (PET), latent heat flux (LE), and gross primary product (GPP) were obtained for a period of eighteen years, and their monthly average was extracted and used as features in the model. The models were trained using eighty percent of the observations with the annual district-wise sugarcane yield as the response variable. Iterative feature selection was done based on correlation factor and feature importance to reduce the dimensionality of the data from around a hundred features to twenty-four. The R 2 metric was used as the evaluation metric to choose the best predictive model. The study showed results with moderate accuracy and was used to estimate the sugarcane crop yield for the year 2019. The highest R 2 of 0.66 and an RMSE value of 7.15 t/ha were obtained using the GBR algorithm by using seven variables and 24 features. The model was very closely followed by the XGB model with an R 2 of 0.65 and an RMSE value of 7.20 t/ha. The FPAR-based features contributed the most to the model followed by the LAI and NDVI features. The simple methodology used in the study uses ready-to-use satellite products and has operationalization potential. The model can be improved by incorporating more satellite-derived parameters and an accurate crop mask to avoid spectral interference from other cropland.
Chapter
The traditional machine learning algorithms are giving way to approaches for deep learning in computer vision, which refers to a computer's capacity to infer meaning from digital images and videos. Sugarcane categorization is important for agricultural management and monitoring. Traditional crop categorization methods based on manual inspection or restricted ground-based data gathering are time-consuming and frequently inaccurate. As a result, an automated and efficient strategy is suggested that requires the use of remote sensing data and the capabilities of deep learning algorithms. A dataset made from multispectral Sentinel imagery is used for the classification of sugarcane. This approach seeks to separate sugarcane-growing regions from other regions in Sentinel-2 images using VGG19, MobileNetV2, and CNN as feature extractors. These findings illustrate the feature extraction utilizing deep learning models with an SVM classifier for sugarcane. By considering variables such as distinct spectral bands, temporal fluctuations, and potential difficulties in separating sugarcane from other land cover types, the objective is to construct and check working of deep learning models for categorizing sugarcane locations using Sentinel-2 data. The sugarcane classification can further be used to find dense and sparse vegetation after the classification is done with deep learning models. The outcomes of this study will help to improve sugarcane categorization techniques and will help farmers, researchers, and agricultural stakeholders make better crop management, yield estimation, and resource optimization decisions in sugarcane farming.
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Sugarcane is a major cash crop grown in India. Several empirical, semi-empirical and mechanistic models have been used to compute and predict sugarcane yield using satellite data. Reliable data predictions are necessary for important decision-making situations. This study attempted a semi-empirical Light Use Efficiency (LUE) model to compute the field-level sugarcane yield for a mill catchment in Uttar Pradesh, India. The phenology parameters, Start of Season and End of Season, for each field were derived by fitting the Sentinel-1 VH backscatter data using the Savitzky-Golay filter. Later these fields were grouped into four classes based on their key phenology parameters. Photosynthetically Active Radiation (PAR) was computed from INSAT-3D data and calibrated based on the ground information. The fraction of absorbed PAR was computed using Sentinel-2 images and ground truth Leaf Area Index observations. The model was limited to using temperature and water stress factors. Water stress was computed using the Land Surface Water Index from Sentinel-2. ERA5's 2 m temperature data were used to compute the stress caused by temperature. LUE and Harvest index were used as constants. The study yielded very satisfying results. The observed and predicted data had an agreement index of 0.91 and a Root Mean Square Error of 46.6 q/ha. The results improved substantially after the calibration of the INSAT-3D insolation. This study overcomes the limitation of varying planting and harvesting dates which are usually not accounted for in LUE-based yield estimation.
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Crop typing at cadastral level is considered as an important input for precision farming, farm management, crop water requirement, crop yield assessment, and crop insurance settlement among others. Advances in satellite remote sensing, Geographic Information System (GIS), classification algorithms, and computational infrastructure provided us the opportunity to classify and map crop types at cadastral level. However, it remains a question that, which particular method of classification is best for a given site? especially when it comes to map the crops at cadastral level using satellite data. The current work is an attempt to answer this question using a combination of five data types (including, optical, SAR, merged optical and SAR, time series optical, and time series SAR), and four popular classification algorithms (including Unsupervised k-mean, supervised Maximum likelihood (MXL), Support vector machine (SVM), and Random Forest (RF)). Results reveal that the time series of optical and microwave data performs better with random forest classifiers (over all accuracy ranging between 67 to 73% and Kappa coefficient ranging from 0.54 to 0.60) as compared to other combinations and classifiers, when a 100% accuracy check approach (new approach) was used. The most of the errors occur at the margin pixels due to mixing. The current finding is applicable for a large part of the nation corresponding to heterogeneous cropping, especially during monsoon season.
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Several machine-learning algorithms have been proposed for remote sensing image classification during the past two decades. Among these machine learning algorithms, Random Forest (RF) and Support Vector Machines (SVM) have drawn attention to image classification in several remote sensing applications. This paper reviews RF and SVM concepts relevant to remote sensing image classification and applies a meta-analysis of 251 peer-reviewed journal papers. A database with more than 40 quantitative and qualitative fields was constructed from these reviewed papers. The meta-analysis mainly focuses on: (1) the analysis regarding the general characteristics of the studies, such as geographical distribution, frequency of the papers considering time, journals, application domains, and remote sensing software packages used in the case studies, and (2) a comparative analysis regarding the performances of RF and SVM classification against various parameters, such as data type, RS applications, spatial resolution, and the number of extracted features in the feature engineering step. The challenges, recommendations, and potential directions for future research are also discussed in detail. Moreover, a summary of the results is provided to aid researchers to customize their efforts in order to achieve the most accurate results based on their thematic applications.
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Sugarcane crop identification and crop distribution information provides an important basis for crop acreage and yield estimation. In this study three methods i.e. object-based classification, multi-date supervised classification and knowledge-based classification methods were used for the analysis of multi-temporal LISS-III and single date LISS-IV image of Resourcesat-2A satellite. The comparison of classification results showed that planted sugarcane area overlapping was ranging from 79.30% to 91.66% and ratoon sugarcane area overlapping was ranging from 61.17% to 79.44%. Further, the classification results for planted and ratoon sugarcane at pixel levels were integrated to increase the reliability of results using the decision tree method. The integration of all the three classification results increased the overall accuracy that was 86.15% with kappa coefficient of 0.73. The use of remote sensing techniques to extract the sugarcane field information is an economically effective method that can be further used for modelling crop production in the region, forecast crop production and management of resources.
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The objective of this research work aims at crop acreage estimation at mill catchment level, derivation of sugarcane phenology and yield estimation at field level. The study was carried out in Kisan Sahkari Chini Mill catchment, Nanauta, Saharanpur, Uttar Pradesh. Extensive and systematic field sampling was carried out for ground-truth observations, biophysical measurements (LAI and above/below canopy PAR) and mill-able cane yield through crop cutting experiments. Major emphasis were laid on sugarcane crop discrimination, biophysical parameter estimation, generation of phenological metrics and yield model development for sugarcane crop at mill catchment level. Sugarcane crop discrimination and its acreage estimation was done using multi-sensor satellite data. The sugarcane classification accuracies were > 92% for LISS-IV, > 86% for Landsat-8 and > 83% for LISS-III classified image. The sugarcane phenological matrices at field level derived using time-series of NDVI for a period of 2015–2016 through TIMESAT software. To retrieve the biophysical parameters particularly leaf area index, best predictive function developed with vegetation indices (EVI, NDVI, SAVI) through correlation and regression analysis along this cane yield estimation attempted with multi-date (eight-day) NDVI from Landsat OLI. Yield models developed for ratoon cane and planted cane explained variance in yield significantly with coefficient of determination (R²) values equal to 0.83 and 0.69, respectively. Similar predictive functions were also established with monthly composite dataset for village-level yield estimates with step wise regression (R² = 0.83) (P = 0.00001), Multi linear regression (MLR) (R² = 0.792) (P = 0.00081) and Random forest regression (R² = 0.466) (P = 0.038).
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Crop classification is a key issue for agricultural monitoring using remote sensing techniques. Synthetic Aperture Radar (SAR) data has an advantage in crop classification because of its all-weather imaging capabilities. The objective of this study was to investigate the capability of SAR data for estimation of cotton and maize area in Perambalur district of Tamil Nadu. The multi-temporal Sentinel-1 SAR data was acquired from 2nd September, 2017 to 24th January, 2018. Both the Vertical-Vertical (VV) and Vertical-Horizontal (VH) polarized data was used. Ground truth data collection was performed for cotton and maize during the vegetative, flowering and harvesting stages. Sixty per cent of the ground truth data were used for training and remaining forty per cent were utilized for validation. The temporal backscattering coefficient (σ0) for cotton and maize were extracted using the training datasets.. The mean backscattering values for cotton crop during the entire cropping period had a range from −11.729 dB to −8.827 dB and from −19.167 dB to −14.186 dB for VV and VH polarization respectively. For maize crop it ranged from −11.248 dB to −8.878 dB and from −19.043 dB to −14.753 dB for VV and VH polarized data respectively. The Spectral Angle Mapper (SAM) and Decision Tree classifier (DT) methods were adopted for cotton and maize area estimation. SAM classified 73259 and 51489 hectares (ha) as cotton and maize respectively in VV polarization. DT classified the area of 61501 and 64530 ha for cotton and maize respectively in VH polarization. The accuracy measures, such as overall accuracy, producer’s accuracy and user’s accuracy and kappa coefficient were estimated. SAM classifier exhibits the overall accuracy of 73.3% for VV Decision tree classifier reported the overall accuracy of 75.0% for VH. It is evident from the present study, that the multi-temporal Sentinel-1 SAR sensor can be well used for the discrimination of cotton and maize crops because of its high temporal resolution which captures the complete phenology of the crops during the cropping period.
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Post-disaster recovery (PDR) is a complex, long-lasting, resource intensive, and poorly understood process. PDR goes beyond physical reconstruction (physical recovery) and includes relevant processes such as economic and social (functional recovery) processes. Knowing the size and location of the places that positively or negatively recovered is important to effectively support policymakers to help readjust planning and resource allocation to rebuild better. Disasters and the subsequent recovery are mainly expressed through unique land cover and land use changes (LCLUCs). Although LCLUCs have been widely studied in remote sensing, their value for recovery assessment has not yet been explored, which is the focus of this paper. An RS-based methodology was created for PDR assessment based on multi-temporal, very high-resolution satellite images. Different trajectories of change were analyzed and evaluated, i.e., transition patterns (TPs) that signal positive or negative recovery. Experimental analysis was carried out on three WorldView-2 images acquired over Tacloban city, Philippines, which was heavily affected by Typhoon Haiyan in 2013. Support vector machine, a robust machine learning algorithm, was employed with texture features extracted from the grey level co-occurrence matrix and local binary patterns. Although classification results for the images before and four years after the typhoon show high accuracy, substantial uncertainties mark the results for the immediate post-event image. All land cover (LC) and land use (LU) classified maps were stacked, and only changes related to TPs were extracted. The final products are LC and LU recovery maps that quantify the PDR process at the pixel level. It was found that physical and functional recovery can be mainly explained through LCLUC information. In addition, LC and LU-based recovery maps support a general and a detailed recovery understanding, respectively. It is therefore suggested to use the LC and LU-based recovery maps to monitor and support the short and the long-term recovery, respectively.
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More than 90% of the sugar production in China comes from sugarcane, which is widely grown in South China. Optical image time series have proven to be efficient for sugarcane mapping. There are, however, two limitations associated with previous research: one is that the critical observations during the sugarcane growing season are limited due to frequent cloudy weather in South China; the other is that the classification method requires imagery time series covering the entire growing season, which reduces the time efficiency. The Sentinel-1A (S1A) synthetic aperture radar (SAR) data featuring relatively high spatial-temporal resolution provides an ideal data source for all-weather observations. In this study, we attempted to develop a method for the early season mapping of sugarcane. First, we proposed a framework consisting of two procedures: initial sugarcane mapping using the S1A SAR imagery time series, followed by non-vegetation removal using Sentinel-2 optical imagery. Second, we tested the framework using an incremental classification strategy based on S1A imagery covering the entire 2017–2018 sugarcane season. The study area was in Suixi and Leizhou counties of Zhanjiang city, China. Results indicated that an acceptable accuracy, in terms of Kappa coefficient, can be achieved to a level above 0.902 using time series three months before sugarcane harvest. In general, sugarcane mapping utilizing the combination of VH + VV as well as VH polarization alone outperformed mapping using VV alone. Although the XGBoost classifier with VH + VV polarization achieved a maximum accuracy that was slightly lower than the random forest (RF) classifier, the XGBoost shows promising performance in that it was more robust to overfitting with noisy VV time series and the computation speed was 7.7 times faster than RF classifier. The total sugarcane areas in Suixi and Leizhou for the 2017–2018 harvest year estimated by this study were approximately 598.95 km2 and 497.65 km2, respectively. The relative accuracy of the total sugarcane mapping area was approximately 86.3%.
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Sugarcane is a major crop for sugar and ethanol production and its area has increased substantially in tropical and subtropical regions in recent decades. Updated and accurate sugarcane maps are critical for monitoring sugarcane area and production and assessing its impacts on the society, economy and the environment. To date, no sugarcane mapping tools are available to generate annual maps of sugarcane at the field scale over large regions. In this study, we developed a pixel- and phenology-based mapping tool to produce an annual map of sugarcane at 10-m spatial resolution by analyzing time-series Landsat-7/8, Sentinel-2 and Sentinel-1 images (LC/S2/S1) during August 31, 2017 - July 1, 2019 in Guangxi province, China, which accounts for 65% of sugarcane production of China. First, we generated annual maps of croplands and other land cover types in 2018. Second, we delineated the cropping intensity (single, double and triple cropping in a year) for all cropland pixels in 2018. Third, we identified sugarcane fields in 2018 based on its phenological characteristics. The resultant 2018 sugarcane map has producer, user and overall accuracies of 88%, 96% and 96%, respectively. According to the annual sugarcane map in 2018, there was a total of 8940 km² sugarcane in Guangxi, which was ~1% higher than the estimate from the Guangxi Agricultural Statistics Report. Finally, we identified green-up dates of those sugarcane fields in 2019, which could be used to support the sugarcane planting and management activities. Our study demonstrates the potential of the pixel- and phenology-based sugarcane mapping tool (both the algorithms and the LC/S2/S1 time series images) in identifying croplands, cropping intensity and sugarcane fields in the complex landscapes with diverse crop types, fragmented crop fields and frequent cloudy weather. The resultant annual maps from this study could be used to assist farms and sugarcane mills for sustainable sugarcane production and environment.
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Sugarcane is an important type of cash crop and plays a crucial role in global sugar production. Clarifying the magnitude of sugarcane planting will likely provide very evident supports for local land use management and policy-making. However, sugarcane growth environment in complex landscapes with frequent rainy weather conditions poses many challenges for its rapid mapping. This study thus tried and used 10-m Sentinel-2 images as well as crop phenology information to map sugarcane in Longzhou county of China in 2018. To minimize the influences of cloudy and rainy conditions, this study firstly fused all available images in each phenology stage to obtain cloud-free remote sensing images of three phenology stage (seedling, elongation and harvest) with the help of Google Earth Engine platform. Then, the study used the fused images to compute the normalized difference vegetation index (NDVI) of each stage. A three-band NDVI dataset along with 4000 training samples and 2000 random validation samples was finally used for sugarcane mapping. To assess the robustness of the three-band NDVI dataset with phenological characteristics for sugarcane mapping, this study employed five classifiers based on machine learning algorithms, including two support vector machine classifiers (Polynomial-SVM and RBF-SVM), a random forest classifier (RF), an artificial neural network classifier (ANN) and a decision tree classifier (CART-DT). Results showed that except for ANN classifier, Polynomial-SVM, RBF-SVM, RF and CART-DT classifiers displayed high accuracy sugarcane resultant maps with producer's and user's accuracies of greater than 91%. The ANN classifier tended to overestimate area of sugarcane and underestimate area of forests. Overall performances of five classifiers suggest Polynomial-SVM has the best potential to improve sugarcane mapping at the regional scale. Also, this study observed that most sugarcane (more than 75% of entire study area) tends to grow in flat regions with slope of less than 10°. This study emphasizes the importance of considering phenology in rapid sugarcane mapping, and suggests the potential of fine-resolution Sentinel-2 images and machine learning approaches in high-accuracy land use management and decision-making.
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Pre harvest prediction of sugarcane and sugar production is essential for obtaining the objectives of the national food security mission. Traditional field experimentation results are not reliable and are biased. Improvement in the accuracy and timeliness of crop yield estimation by blending of ancillary data and remotely sensed data in the temporal domain is indispensable. Ratoon sugarcane and planted sugarcane are the two prevalent agricultural practices in India. Ratoon sugarcane crop is suitable both from economic and production consideration. Identification of ratoon sugarcane and monitoring of its growth has been poorly studied. The objective of this study is to extract the information related to the ratoon sugarcane using remote sensing data. The present study proposed NDVIT, an index based on temporal values of NDVI data of Landsat 8 for monitoring and discrimination of ratoon sugarcane. This index has been found to provide 91% accuracy when tested on the ground in the Himalayan foothills region of Uttarakhand. Study indicated that the best period for discrimination of ratoon sugarcane crop is during the first week of April and last week of August to the end of September. This matches with the start of tillering stage and during the period of grand growth stage of the sugarcane.
Article
Image classification is one of the crucial techniques in detecting the crops from remotely sensed data. Crop identification and discrimination provide an important basis for many agricultural applications with various purposes, such as cropping pattern analysis, acreage estimation, and yield estimation. Accurate and faster estimation of crop area is very essential for projecting yearly agriculture production for deciding agriculture policies. Remote sensing is a technique that allows mapping of large areas in a fast and economical way. In many applications of remote sensing, a user is often interested in identifying the specific crop only while other classes may be of no interest. Indian Remote Sensing Satellite (IRS-P6) LISS IV sensor image of spatial resolution 5.8 m has been used to identify the sugarcane crop for the Chhapar village of Muzaffarnagar District, India. Classification of satellite data is one of the primary steps for information extraction for crop land identification. In recent years, decision tree approach to image analysis has been developed for the assessment and improvement of traditional statistically based image classification. In this study, ISODATA, MLC, and vegetation indices based decision tree approaches are used for classifying LISS IV imagery. The 11 vegetation index images have been generated for decision tree classification. All the three methods are compared and it is found that the best performance is given by the decision tree method. Vegetation indices based decision tree method for sugarcane classification, the user’s accuracy, producer’s accuracy, overall accuracy, and kappa coefficient were found 88.17, 86.59, and 87.93% and 0.86 respectively.