Assessing the ability of soil microorganisms to dissolute poorly soluble native calcite to supply Ca2+ is a new area to be explored in reclaiming sodic soils by supplying adequate Ca2+ and reducing the recurrent sodicity. Hence, the present study aimed to isolate a calcite dissolving bacteria (CDB) from calcareous sodic soils and to understand the mechanism of calcite dissolution. Of the 33 CDB...

rganic matter and clay miner0 als in soils have negatively charged surfaces that act much like cation exchange resins. When more than 15% of the exchange sites are neutralized by Na+ and the final ionic strength of the aqueous extract is less than about 0.04 M, the clays and organic matter are dispersed. Under these conditions, the solution pH is usually greater than 8.4, and carbonate (COi-) a...

Soil correction is one of the ways in agriculture lands development. The sodic ion alongside salin vocalizes the salin-sodic soil and cause divulge in plants growth. So necessary coure of action for the Soil correction by physical and chemical ways such as usage of calsium on the leaching is inevitable. In this study, area soils are digged from deep profiles of 0-20, 20-40, 40-60, 60-80 and 80-...

Increased Na+ ions negatively affect soil physicochemical characteristics. We ran a pot incubation experiment for 2 months and leaching another to monitor the effects of nano-gypsum (NG, <100 nm) in low affordable doses on improving saline-sodic Treatments included control (CK), conventional gypsum (CG; ≤ 0.5 mm) at 100% CG requirement (8.9 t ha−1: CGR), three NG (240, 480 960 kg ha−1 = 2.7%, 5...

Soil samples from the Jakara irrigation project site were evaluated with respect to possible degradation caused by irrigation. Most of the soils were neutral to alkaline with pH values ranging between 6.58 + 0.04 and 10.45 + 0.03. The electrical conductivity ranged from 0.3 + 0.01 to 75.2 + 0.06 dSm-1 which implies low to very high salinity. The concentrations of the exchangeable cations in the...

Our aim in this work is (1) to characterize mineralogically and geochemically the brown amphibole and other minerals filling millimetric veins in the Cóbdar metabasalts of the Betic ophiolites in southern Spain, and (2) to deduce their genetic conditions, mainly with the aid of the optical microscopy and analytical electron-microprobe analysis, complemented by transmission and analytical electr...