Plant-available zinc in arable soils and gassland in relation to levels of intensification in districts of Belarus

russe. На материале крупномасштабного агрохимического обследования установлен нарастающий дефицит подвижных форм цинка в пахотных и луговых почвах, который является следствием несбалансированной интенсификации земледелия, отрицательного баланса гумуса и подкисления почв. Выделены четыре группы районов, где потери подвижного цинка за период 1996–2012 гг. различались – 62 – 44 – 14 – 0% от исходного содержания соответственно. В результате существенно возросла потребность сельскохозяйственных культур в цинксодержащих удобрениях. Дается прогноз содержания подвижных форм цинка в пахотных почвах на период до 2020 г. по выделенным группам районов для возможных трех сценариев.

anglais. Zinc appears one of the most important trace elements for plant growing. On the basis of the data of a large agrochemical survey the increasing deficit of mobile Zn in arable soils and grasslands has been determined as a result of unbalanced intensification of arable farming, negative balance of organic matter and soil acidification. Four groups of regions with deferent losses of mobile Zn (62–44–14–0 % of the initial content) for the period 1996–2012 have been identified. It results in the increasing demand of agricultural crops for Zn fertilization. Grading of soils according mobile zinc content has been made. Dynamics of application of mineral and organic fertilizers and pasture’s productivity in the Republic of Belarus for the period of 1985-2012 has been analyzed. Cropping structure and humus content in arable lands has been evaluated. Change in humus content in arable lands in comparison to manure application and cropping structure for the period of 1996-2012 has been measured. Distribution of the arable lands, improved grasslands and pastures of the Republic of Belarus according to the groups of mobile zinc supply, 2009-2012, has been investigated. Losses of mobile zinc forms for the period of 1996-2012 depending on the acidic soils’ area (pH less than 5.0) by the regions of the republic have been measured. The prognosis of mobile Zn content in arable soils in respect of the identified groups of regions for the period to 2020 has been presented.