Abstract
Crop phenology is a significant factor that affects the precision of crop area extraction by using the multi-temporal vegetation indices (VIs) approach. Considering the phenological differences of maize among the different regions, the summer maize cultivated area was estimated by using enhanced vegetation index (EVI) time series images from the Moderate Resolution Imaging Spectroradiometer (MODIS) over the Huanghuaihai Plain in China. By analyzing the temporal shift in summer maize calendars, linear regression equations for simulating the summer maize phenology were obtained. The simulated maize phenology was used to correct the MODIS EVI time series curve of summer maize. Combining the mean absolute distance (MAD) and p-tile algorithm, the cultivated areas of summer maize were distinguished over the Hunaghuaihai Plain. The accuracy of the extraction results in each province was above 85%. Comparing the maize area of two groups from MODIS-estimated and statistical data, the validation results showed that the R2 reached 0.81 at the city level and 0.69 at the county level. It demonstrated that the approach in this study has the ability to effectively map the summer maize area over a large scale and provides a novel idea for estimating the planting area of other crops.
Highlights
Maize, as the primary staple, plays a vital role in agricultural production in China
mean absolute distance (MAD) [18] was selected as the indicator of similar comparing the similarity between the actual Moderate Resolution Imaging Spectroradiometer (MODIS) enhanced vegetation index (EVI) pixel and the standard summer maize EVI
Each raster summer maize the value template, and mk maize in the sequence; n is the total number of the time series (n is 1; xik is the actual value of MODIS EVI in the k sequence; xjk is the standard EVI value of summer maize in the sequence; n is the total number of the time series (n = 9)
Summary
As the primary staple, plays a vital role in agricultural production in China. Wang et al considered the differences in maize phenology with latitude to discriminate the summer maize based on the multi-temporal MODIS EVI images over the Huanghuaihai Plain [22]. There is, the phenological differences of maize caused by various environmental factors being combined with the multi-temporal MODIS EVI images to map the cultivated area of summer maize for better extraction accuracy on a large scale. The summer maize planting area was discriminated successfully in the study area It provides a novel idea for improving the accuracy of maize area extraction using multi-temporal remote sensed data on a large scale
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
