TRIPATHI, D.CHANDEL, SUNITA2016-11-292016-11-29201348049http://krishikosh.egranth.ac.in/handle/1/88061ABSTRACT The change in soil health indicates whether the management practices being adopted are sustainable or not. Therefore, sustainability of intensive agriculture system is intimately linked to maintenance or enhancement of soil health. Present study was therefore, undertaken during 2012-2013 to investigate the impact of intensive cultivation on soil health under polyhouses. Studies reveal that the bulk density ranged from 1.16 to 1.29 g/cc and the soils are good for root proliferation and plant growth. The particle density ranged from 2.07 to 2.21 g/cc, whereas the porosity ranged from 40.86 to 47.65 per cent. Amongst the chemical properties the chloride content ranged from 0.04 to 0.07 c mol (p+)/kg, bicarbonate content ( 1.02 to 2.01cmol (p+)/kg) and CEC (13.52 to 15.85 cmol (p+)/kg), were found to be normal without any adverse effect on soil health. The soil pH in the three districts ranged from 6.58 to 6.89 and the EC values were also low. The organic carbon content varied from 1.40 to 1.66 per cent and was categorized as high. The soil N, P and K ranged from 253.48 to 352.42, 40.41 to 87.6 and 453.94 to 495.06 kg/ha, respectively. With the exception of N at some locations, all the soils were high in these nutrients. The exchangeable Ca was found to be adequate, however soils show low levels of exchangeable Mg. Sulphur (62.47 to 72.14 kg/ha) was also high in the soils. Amongst the micronutrients, available Zn, Fe, Cu and Mn were found to be medium to high in availability, both under polyhouse and open conditions. The microbial biomass ranged from 377.13 to 459.89 µg/g, which fell under medium to high range for categorizing soil health. The soil indicators like pH, bicarbonate, CEC, N, K, Ca, Mg and micronutrients had less influence on soil health, while, EC, OC, P, S, chloride and MB had more influence under both open and polyhouse conditions. The results indicated that the majority of the soils in polyhouse conditions were in high soil health condition, accounting for 57% of the survey samples, followed by the very high (40%) and medium health soil (3%). Whereas, in case of open condition majority of the soil were at high health level (53%) followed by very high (27%) and medium soil health (20%). Soil health was found to be affected by the management practices adopted by the farmer and the extent of fertilizer use over a period of time.enSOIL HEALTH ASSESSMENT UNDER PROTECTED CULTIVATION OF VEGETABLE CROPS IN MID HILL ZONE OF HIMACHAL PRADESHThesis