Класифікація агрочорноземів Західноукраїнського краю

Abstract

Запропонована класифікація агрочорноземів на лесових породах Західноукраїнського краю та її корелятивна відповідність з WRB. Агрочорноземи регіону входять до асоціації акумулятивно-гумусових ґрунтів, сімейства нейтральних і слабокислих Са-гумусових, а також середньокислих Н-гумусових ґрунтів. Виділено два генетичні типи агрочорноземів (типові та попільнякові), які поділено на роди (міграційно-міцелярні, деградовані та криптоглейові).

The classification problem is one of the most topical in Ukrainian pedology. The presence of several Ukraine’s soil classifications developed by various scientists does not solve this problem. The national classification of soils should adequately reflect the peculiarities of pedogenesis on the territory of Ukraine, its structure and content should be harmoniously correlated with WRB. The structural-hierarchical approach based on substantive-genetic principles is the scientific foundation for the development of soil classification. Although all diagnostic characteristics serve as a function of soil-forming processes, its structure and content should be based not on evaluative categories, but on the substantive properties of the soil, defined in terms of diagnostic horizons, properties and materials that can be easily seen and identified in the field. Within the boundaries of the Western Ukrainian krai, chernozems were formed on the loess rocks of the Volyn- Podilskyi and Pre-Carpathian highlands. They occupy an area of 1 million 322 thousand ha, which is 4.8% of the total area of Ukraine’s chernozems. Almost 78% of them that are typical chernozems (the main areas are concentrated in the Khmelnytskyi region), 22% – that are ashen chernozems. Mostly all chernozems of Ukraine have long been used in agriculture and have undergone significant changes, we call them agrochernozems. Agrochernozems of the Western region of Ukraine are distributed on structural and erosive uplands within such administrative regions: Volyn, Rivne, Lviv, Ternopil, Khmelnytskyi, Ivano-Frankivsk, Chernivtsi. The whole kingdom of soils is divided into four divisions – natural or pristine (Biozems), natural-anthropogenic or cultural (Agrozems), man-made or industrial (Technozems), urbanogenic or residential (Urbozems). Agrochernozems of the region belong to the association of accumulative humus soils, the family of neutral and weakly acidic Ca-humus soils, as well as moderately acidic H-humus soils. Two genetic types of agrochernozems within the respective families are distinguished – typical (Chernozems) and ashen (Phaeozems). The specific combination of humus and middle horizons in the agrochernozem profile characterizes the entire diversity of agrochernozems on the loess rocks of the research area. Diagnostic criteria for the horizons of the investigated agrochernozems are proposed, namely: double humus horizon (H + Hp); middle horizons (accumulativecarbonate Рhk, clayey-illuvial РItm, cryptoglay (textural-hydro-metamorphosed) РImgl; mole loess horizon Рhk. Soil belonging to the appropriate association and family is determined by the properties of humus soil only. For soil diagnosis at lower taxonomic levels, humus soil parameters are also used. Middle horizons are typodiagnostic. The properties of the «mole loess» horizon and the parent rock are diagnostic indicators at the level of the order, sometimes at the level of the genus. The types of agrochernozems are divided into groups of genera: migration-micellar, degraded and cryptogley according to the ratio of the processes ofleaching and carbonation, the degree of development of soil degradation and regradation, as well as the degree of profile gleying. The proposed classification of agrochernozems on loess rocks of the Western Ukrainian krai is an example of the correct correlative correspondence between the classification of soils of Ukraine and the World Reference Base for Soil Resources (WRB). Regarding the depth of carbonates occurrence, typical migration-micellar agrochernozems are divided into three evolutionary genera: migration-micellar (own genus) – Haplic Chernozems (Aric, Pachic) by WRB; carbonate – Calcic Chernozems (Aric, Pachic); leached – Luvic Chernozems (Aric, Pachic). The four evolutionary genera in the composition of ashen agrochernozems are distinguished: degraded (own genus) – Luvic Greyzemic Phaeozems (Aric); weakly regraded – Katocalcaric Luvic Greyzemic Phaeozems (Aric); strongly regraded – Katocalcaric Luvic Phaeozems (Aric); cryptogley – Luvic Greyzemic Katogleyic Phaeozems (Aric).