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Mitigation of Iron Toxicity and Iron,Zinc, and Manganese Nutrition of Wetland Rice Cultivars (Oryza sativa L.) Grown in Iron‐Toxic Soil
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The Dst (Disturbance storm time) index is a measurement of earth geomagnetic activity and is widely used to characterize the
geomagnetic storm. It is calculated on the basis of the average value of the horizontal component of the earth’s magnetic
field at four observatories, namely, Hermanus (33.3° south, 80.3° in magnetic dipole latitude and longitude), Kakioka (26.0°
north, 206.0°), Honolulu (21.0° north, 266.4°), and San Juan (29.9° north, 3.2°) and is expressed in nano-Teslas. The strength
of the low-latitude surface magnetic field is inversely proportional to the energy content of the ring current around earth
caused by solar protons and electrons, which increases during geomagnetic storms. Thus a negative Dst index value indicates
that the earth’s magnetic field is weakened which is specifically the case during solar storms. Predicting Dst index is a
difficult task due to its structural complexity involving a variety of underlying plasma mechanism. For characterizing and
forecasting this complex time series, a formal model must be established to identify the specific pattern of the series. Persistent
demand for a fool proof model of Geomagnetic Dst index prompted us to investigate the Dst Time Series mechanism with a very
recent technique called Visibility Algorithm and it is observed that the Dst time series follows the same model that of a
Stochastic Fractional Brownian motion having long range correlation. 相似文献
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