Wheat Acreage Estimation Using Remote Sensing in Tarai Region of Uttarakhand

*Corresponding author Email : [email protected] INTRODUCTION In India agriculture plays a strategic role as this sector is the mainstay of the country’s economy. About 18% of the national income is from this sector which provides employment to about more than half of the work force in the country (Kothai 2011). Significant progress has been made in food grain production in India over the years, with a record 241.56 million tons in 2010-11 (Murugesa Boopathi 2011). During 2008, India ranked second in the world with regard to production of wheat (79 mt). India is also main consumer of wheat in the world. After the Green Revolution in the 1970's and 1980's the production of wheat has shown a huge increment. The major States involved in wheat cultivation are those located in the plains of Uttar Pradesh, Uttarakhand, Punjab and Haryana. They account for nearly 70 per cent of the total wheat produced in the country (Nainwal 2009). Wheat is a rabi crop and is hence grown during the winter season in India. Sowing of wheat occurs in October-November and the crop is finally harvested during the months of March-April. Wheat crop requires warm temperate climatic conditions with moderate temperature and rain fall during the growing season and bright sunshine at the time of ripening and harvest. It requires a rainfall of about 50 cm to 100 cm during its growing phase. Too much rain is injurious to the plant. Alluvial soils are ideal for wheat cultivation and that is why the fertile plains of the IndoGangetic region are most conducive for wheat cultivaA field study has been carried out in Pantnagar; district U.S. Nagar of Uttarakhand State for wheat acreage estimation, during Rabi season of the year 2010-2011. Two types of data viz. satellite data of Haldwani region dated 22 March 2010 and ground truth data have been used for the study. ENVI-4.8 (Environment for Visualizing Images-4.8) software was used for image pre processing and analysis of the data. Wheat crop at the maximum vegetative stage was used to capture the crop spectral characteristics. Supervised classification was used to identify the wheat crop in Pantnagar. Ground truth data combined with visual interpretation obtained from LANDSAT image dated 22 March 2010 were used as training sets for supervised classification. The training pixels were selected from different fields. The total numbers of five classes were identified for which separate ROIs (Region of Interest) were generated in order to train the image processing software. The accuracy of the classification was determined by comparing the test set with the classification results to generate producers, user’s and the overall accuracies. The overall accuracy obtained was 100%. Post classification statistics was generated to find out pixels belonging to different categories. The acreage of all the classes was computed by multiplying the total number of pixels in a category with the area of single pixel. The size of each pixel in LANDSAT image is 30m and hence the area covered by each pixel is 30mx30m (900m). The total number of pixels obtained was 16,495. Therefore, total area under study was found to be 1484.55 ha.