Wavelet and non-parametric statistical based approach for long term land cover trend analysis using time series EVI data

Abstract

Land cover change analysis was carried out using Moderate Resolution Imaging Spectroradiometer (MODIS) Enhanced Vegetation Index (EVI) time series data for the period 2005–2014. MODIS EVI data coupled with Quality Assessment Science Data Sets (QASDS) was de-noised with Savitzky–Golay filter while enhancing quality and preserving the temporal profile of EVI. Wavelet transform (WT) based approach along with Sen slope’s method was used for land cover change and trend analysis. The WT based approach is useful for studying multiscale and non-stationary processes. Mann–Kendall test was performed to confirm the significance of the identified trends. Proposed approach identified 358 locations as change points, where 285 (79.6%) and 73 (20.4%) locations were detected as ‘Change’ and ‘False Change’ with respect to high resolution images. The proposed approach is useful for monitoring land cover changes that provide vital inputs for sustainable management of land resources.

Keywords:

• Land cover change
• EVI
• time series
• Savitzky–Golay filter
• wavelet transform

Acknowledgements

The authors thank Director, NRSC for encouraging this work. We acknowledge NASA Earth observing system (http://e4ftl01.cr.usgs.gov/MOLT/MOD13Q1.005/) for providing free MOD13Q1 products. We also acknowledge Climate Forecast System Reanalysis (CFSR) global meteorological dataset (http://globalweather.tamu.edu) for providing free historical rainfall and temperature data. We sincerely appreciate the anonymous reviewers for improving the quality of the manuscript.

Disclosure statement

No potential conflict of interest was reported by the authors.