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An attempt was made to identify priority zones of available micronutrients in the soils of agro-ecological subregions (AESR) of north-eastern states of India (Assam, Nagaland, Sikkim and Tripura) using geo-spatial techniques. Surface soil samples (0-25 cm) were collected from Assam (AESRs 15.2, 15.3, 15.4 and 17.1), Nagaland (AESR 17.1), Sikkim (AESR 16.2) and Tripura (AESR 17.2) and analysed for pH, organic carbon and DTPA-extractable micronutrients (Fe, Mn, Zn and Cu) by standard procedures. Regular Spline was employed as spatial interpolation techniques for obtaining spatial distribution of available micronutrients in soils. The AESR map was overlaid on spatial distribution layers to obtain spatial variability of micronutrients in the AESRs of north-eastern regions of India. Zinc deficiency was common in all the AESR. Maximum deficient area of Zn, Mn and Cu was observed in AESR 15.4, and it was regarded as the high-priority zone, whereas AESR 16.2 and AESR 17.2 were considered as low-priority zone. Rainfall, pH and organic carbon appeared to be the key factors in controlling micronutrient availability in soils of north-eastern regions of India.

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Shifting cultivation is widely practiced in the northeastern hill (NEH) region of India. It is known that the destruction of natural forests and its conversion to cropland leads to soil resource degradation. The impacts on soil due to jhuming (jhum practice followed in shifting cultivation) have not been studied adequately. Also, study of alternatives to jhum land use is lacking. In our study, a soil resource inventory of jhum lands was generated for a part of the Purvanchal Ranges of Eastern Himalaya, India to ascertain the nature of soil resource degradation due to jhuming using geo‐spatial techniques. High‐resolution IRS P6 LISS‐IV and stereo‐pair CARTOSAT‐I satellite images along with digital elevation model data were used to map soil resources of jhum lands through a detailed soil survey. Typical pedons were also studied in the native forest adjacent to the jhum lands. Further, land suitability evaluation of the identified soil series for crop growth was carried out to propose alternative land‐use models for jhum lands distributed over different landforms. Results indicated that soils of jhum lands were organically degraded and followed regressive pedogenesis, whereas forest soils followed progressive pedogenesis, particularly on high (650–1250 masl) and medium hills (250–650 masl). Alternaive land‐use models with the inclusion of upland rice and without the inclusion of rice have been proposed. Results of the investigation should be useful for policy makers to seeking make the best use of the land resources under jhum cultivation.

Fields with rice-based cropping systems are unique from other wetland or upland soils because they are associated with frequent cycling between wetting and drying under anaerobic and aerobic conditions. This alters the C and N transformations, microbial activities and their diversity, and soil physical properties, depending on the other crop in rotation with rice. This chapter aims to compare the soil quality of vertisols of central plains of Chhattisgarh under rice-wheat and rice-chickpea cropping systems. Soil quality index was developed using analytical hierarchy process (AHP). Five soil quality indicators were selected under minimum datasets including soil organic carbon, mean weight diameter, available water content, available phosphorous and zinc. The results indicated that the rice-chickpea cropping system shows improved soil quality than that of rice-wheat cropping system.