Papers by karun choudhary
Assessing the extent of hailstorm affected crop is one of the thrust areas for quantifying mid-se... more Assessing the extent of hailstorm affected crop is one of the thrust areas for quantifying mid-season adversaries under crop insurance values chain. This study evaluated the pre- and post-hailstorm responses on spectral bands and vegetation indices derived from Sentinel-2 data for assessing the severity class of the affected potato crop. The potato crop was mapped using pre-event satellite data with overall accuracy of 88% (k=0.82). Pair-wise Games-Howell t-test showed significant differences among the post-hailstorm potato severity classes in Red, Near Infrared & Short-wave Infra-red (SWIR) bands and Normalized vegetation indices. Percentage change (from pre- to post-event) in band reflectance and vegetation indices showed a better sensitivity in differentiating damage severity. Differential behaviour of SWIR-1 (Band-11) and SWIR-2 (Band-12) were observed within severely affected potato crop under dry and wet soil conditions. Decision matrix based on percentage change in Normalized...
Geoderma, 2006
Studies on soil strength and rooting characteristics of crops are important for water and nutrien... more Studies on soil strength and rooting characteristics of crops are important for water and nutrient budgeting and also for deciding the adoption of suitable soil management practice for sustainable crop production. In the present field trial, the variation of soil penetration resistance (PR) with soil water content (SWC (w/w)) and bulk density (BD) changes under bed and conventionally planted wheat was studied on a sandy loam soil of research farm of Indian Agricultural Research Institute, New Delhi. The differences in root characteristics of both systems were also compared. The results showed that, in general for all SWC, with increase in BD from 1.2 to 1.6 Mg m − 3 , PR increased but the increase was more sharp in conventional than in bed planting system. It was further seen that, at all BDs, the critical soil strength of 2 MPa arrived at higher SWC in conventional as compared to bed planting. It thus indicated that root growth continued normally at relative lower SWC in bed planting as compared to conventional planting.
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Papers by karun choudhary