Assessment of the Soil Buffer Capacity in the Sea of Azov Basin Under Heavy Metal Pollution

Heavy metals (HM) are among the most hazardous soil pollutants. The intensity of accumulation and distribution of HM in soils directly depends on the ecological conditions of pedogenesis and its buffering properties. At the same time, a significant accumulation of HM in the soil as a result of anthropogenic impacts reduces the buffering capacity of the soil and its resistance to pollution. The purpose of this work was to assess the buffering capacity of soils to HM pollution in the Don River delta and the coast of the Taganrog Bay of the Sea of Azov undergoing the great anthropogenic impact. The buffer capacity of experimental soils was carried out using the Il’in’s method (1995), based on the calculation of the inactivation ability of soils: organic matter, clay fraction (particle size < 0.01 mm), carbonates, sesquioxides, and pH. The content of HM was compared with soil Clarke and the maximum permissible concentration of HM in soils accepted in the Russian Federation. It was found that the experimental soils could be ordered by buffer capacity value as following (in decreasing order): haplic chernozem ≥ alluvial-meadow light loamy ≥ solonchak > alluvial-meadow sandy and sandy loamy > sandy primitive soil ≥ stratified alluvial soil. Keywords: trace elements, contamination, impact territories

Quality and Optimal Shelf Life of Late Season Green Cabbage

Introduction. Green cabbage has a short shelf life. As a result, it becomes scarce by March and April, often due to miscalculated sell-by-date. The research objective was to establish qualitative indicators and optimal shelf life of late season green cabbage. Study objects and methods. The study featured eleven late season varieties of green cabbage grown in alluvial meadow soil using N150P150K180 as fertilizer. The samples (25 cabbage heads) were put in layers into wooden containers with a capacity of 200–250 kg each and stored at 0...+1°C and a relative humidity of 90–95% for 7 months. By the end of storage, the samples were tested for the yield of marketable products, weight loss, diseases, etc. Results and discussion. The highest yield belonged to Gertsoginya F1 (80.4%), Kilaton F1 (78.6%), and Beaumont Agro F1 (77.7%). The optimal shelf life did not exceed 5–6 months. The yield of commercial products depended on the solid matter content (r = 0.81) and, to a lesser degree, on the average content of ascorbic acid (r = 0.52), monosaccharides (r = 0.55), and nitrates (r = 0.55). The weight loss had a negative mean relationship with the content of solids (r = –0.55), ascorbic acid (r = –0.49), and nitrates (r = –0.59). Conclusion. The optimal shelf life for most varieties and hybrids of green cabbage proved to be 4–5 months, whereas for Beau Monde Agro F1, Gertsoginya F1, Idilliya F1, and Kilaton F1, it was 5–6 months. Further research might reveal hybrids with longer shelf life.

Biological activity and humus state of soils in the near-adjacent part of the Selenga River

Peculiarities of humus formation and manifestation of biological activity of soils are revealed. The objects of research are grey forest nonpodzolized, alluvial meadow soils as arable land, meadow-marsh soils as hayfield. Humus condition of the studied soils is in satisfactory condition within each soil type. The current state of the humus fund of old-arable grey forest soils is characterized by low humus content and unsatisfactory composition, which is caused by the absence of fertility change. The productivity of meadow-marsh soils is high and considerably exceeds grey forest and alluvial meadow soils. The information obtained on biological activity, can be used in agricultural practice to assess soil productivity, as well as in environmental monitoring.

Particle-Size Distribution in Soils of the Khankaiskiy Nature Reserve (Primorye Territory)

Soil texture is determined and the features of particle-size vertical distribution in soils of different landscapes of the Khankaiskiy Nature Reserve are considered. Three variants of the distribution of clay (&lt;0.001 mm) and physical clay (&lt;0.01 mm) fractions along the vertical profiles soils are identified: accumulative, regressive, with a maximum in the middle-profile horizon and with their approximately equal contents in the upper and the lower horizons. A regressive variant is revealed in burozems gleyic, podzoliс-brownzems, dark-humus gley and alluvial meadow gley soils. These soils are characterized by a medium loamy sandy-coarse-dusty composition of the upper horizons and a light- or medium-loamy composition of the middle and lower parts of the profile. The distribution of fine fractions along the profile is observed with a gradual decrease in their content with depth in typical burozems and alluvial meadow gley-ic soils, while the texture of the layer changes from medium loamy to light loamy. The vertical distribution of fine fractions with a maximum in the middle part of the profile is revealed in mucky gley soils. The profile is formed under the influence of a combination of the floodplain process with the introduction and redeposition of suspended particles and gleying. The lithological specificity of the accumulation of the initial parent materials plays a decisive role in the differentiation of fine fractions in the soil profile.

FEATURES OF TEXURE OF SOILS OF THE KHANKAISKIY NATURE RESERVE

Изучение гранулометрического состава почв Ханкайского заповедника показало, что профили почв представляют собой многослойные спектры различного литологического сложения. Сложность почвенных профилей по гранулометрическому составу определяется степенью проявления поемного и аллювиального процессов, литологическими особенностями почвообразующего материала. По типу сложения выделено несколько литологических групп. Темно-гумусовые глеевые, аллювиальные луговые глеевые почвы и буроземы глееватые отличаются резкой дифференциацией профиля по гранулометрическому составу на верхнюю легкую и нижнюю глинистую толщу. Для этих почв отмечено наибольшее содержание фракций физической глины и ила по всему почвенному профилю. Буроземы типичные и аллювиальные луговые глееватые, вышедшие из зоны затопления, характеризуются литологически однородным легким составом. В этих почвах выявлено высокое содержание фракций мелкого песка. The soil profiles the Khankaiskiy Nature Reserve represent multilayer spectra of various lithological addition. The complexity of soil profiles in terms of particle-size distribution is determined by the degree of manifestation of soil and alluvial processes, lithological features of soil-forming material. Several lithological groups are distinguished by the type of texture. Dark humus gley, alluvial meadow gley soils and burozem gleyic shrouds are distinguished by a sharp differentiation of the profile by granulometric composition into an upper light and lower clay thickness. The largest content of fractions of physical clay and silt was noted throughout the profiles for these soils. Burozem typical and alluvial meadow gleyic soils that have emerged from the flood zone characterize this with a lithologically homogeneous light composition. A high content of fine sand fractions was revealed in these soils.

Optimization of onion production technology under annual growing in Non-Chernozem zone

Сегодня лук-репка занимает в стране третье место по площади возделывания среди овощных культур при средней урожайности в 2019 году 27,8 т/га. Потенциал современных сортов и гибридов составляет 100 – 120 т/га. В условиях Нечерноземья проблема поражения лука пероноспорозом наиболее злободневна. Цель исследований – оптимизация элементов технологии производства лука-репки в однолетней культуре (предпосевная обработка семян смесью ризосферных ассоциативных бактерий, нормы и сроки внесения бактерий совместно с минеральными удобрениями, нормы и сроки внесения фунгицидов), обеспечивающих урожайность 70–80 т/га на аллювиальных луговых почвах Нечерноземной зоны. Полевые опыты были проведены на опытном поле ВНИИО согласно стандартных методик. Почва участка аллювиальная луговая среднесуглинистая. Содержание гумуса в слое 0-20 см составляет 3,0–3,2%, pН солевой вытяжки колеблется в значительных пределах 5,0-6,5. Содержание суммы поглощенных оснований 45,0 мг-экв. на 100 г почвы. Содержание Р2О5 – 22,0 мг на 100 г почвы (по Чирикову), калия – 15,2 мг (по Масловой), общего азота — 6,0 мг. В 2018 – 2020 годах было установлено, что: обработка семян лука смесью микробиологических препаратов ризосферных ассоциативных бактерий Экстрасол (штамм Bacillus subtilis Ч-13), Азотовит (штамм Azotobakter chroococcum) и Фосфатовит (штамм Bacillus mucilaginosus) дозами, согласно рекомендаций производителей, не показала достоверного увеличения полевой всхожести испытанных вариантов по отношению к контролю. Внесение смеси ризосферных ассоциативных бактерий препаратов БисолбиСан (штамм Bacillus subtilis Ч-13), Азотовит (штамм Azotobakter chroococcum) и Фосфатовит (штамм Bacillus mucilaginosus) суммарными дозами, л/га: 20,0; 60,0; 70,0;80,0; 90,0; совместно с минеральными подкормками на луке в однолетней культуре обеспечивает значительную (до 20%) прибавку урожайности. Сроки и нормы внесения препаратов требуют дальнейшей оптимизации. Имеет место усиление иммунитета растений против пероноспороза при некорневых обработках фунгицидами Ридомил Голд МЦ и Метаксил совместно с бактериальным препаратом БисолбиСан (штамм Bacillus subtilis Ч-13) в 1% концентрации рабочего раствора. Интервалы обработок 7 – 10 дней фунгицидами Ридомил Голд МЦ и Ревус Топ (на луке не зарегистрирован) следует считать оптимальными против пероноспороза. Currently, the onion-turnip occupies the third place in the country in terms of cultivation area among vegetable crops with an average yield of 27.8 t/ha in 2019 year. The potential of modern sorts and hybrids is 100-120 t/ha. In the conditions of Non-Chernozem zone, the problem of onion disease with peronosporosis is the most urgent. The aim of the research is to optimize the elements of the onion – turnip production technology in an annual crop (pre-sowing seeds treatment with a mixture of rhizospheric associative bacteria, norms and terms of application of bacteria together with mineral fertilizers, norms and terms of application of fungicides), providing a yield of 70-80 t/ha on alluvial meadow soils of the Non-Chernozem zone. Field experiments were conducted at the ARRIVG experimental field according to standard methods. The soil of the site is alluvial meadow medium loamy. The humus content in the 0-20 cm layer is 3.0 — 3.2%, pH of the salt extract varies in the significant range of 5.0-6.5. The content of the sum of absorbed bases is 45.0 mg-eq. per 100 g of soil. The content of P2O5 is 22.0 mg per 100 grams of soil (according to Chirikov), potassium –15.2 mg (according to Maslova), total nitrogen-6.0 mg. In 2018 – 20 years it was found that: Treatment of seeds onion mixture of microbiological preparations associative rhizosphere bacteria Extrasol (strain Bacillus subtilisCH-13), Azotovit (strain Azotobakter chroococcum) and Fosfatovit (strain Bacillus mucilaginosus) doses, according to the manufacturer's recommendations, did not show a significant increase in germination tested options with respect to the control; Introduction of a mixture of rhizospheric associative bacteria preparations BisolbiSan (Bacillus subtilis strain CH-13), Azotovit (Azotobakter chroococcum strain) and Fosfatovit (Bacillus mucilaginosus strain) in total doses, l/ha: 20,0; 60,0; 70,0;80,0; 90,0; together with mineral fertilizing on the onion in an annual crop, it provides a significant (up to 20%) increase in yield. The terms and rates of application of drugs require further optimization. There is an increase in the immunity of plants against peronosporosis during non-root treatments with fungicides Ridomil Gold MC and Metaxil together with the bacterial preparation BisolbiSan (Bacillus subtilis strain CH-13) in 1% concentration of the working solution. Treatment intervals of 7-10 days with the fungicides Ridomil Gold MC and Revus Top (not registered on the onion) should be considered optimal against peronosporosis.

TO SOLVE THE PROBLEMS OF DIAGNOSING THE GROSS RESOURCE OF LICORICE ROOT AND ITS EXTRACTION IN THE VOLGA-AKHTUBA FLOODPLAIN

The article reflects the results of many years of research on the study of the root system of naked licorice (Glycyrrhiza glаbra L.). The formation of this valuable plant occupies significant areas of the Volga-Akhtuba floodplain. The work was carried out in order to establish the regularities of the formation and accumulation of roots in local populations of licorice in order to diagnose their reserves with subsequent scientific substantiation of technological regulations for the industrial production of licorice, which guarantee self-restoration of cenopopulations. Based on the totality of morphological and ecological features, the diversity of adaptability of architectonics, the root system of licorice can be regarded as ecologically universal and, in some respects, unique. The multivariance of its structure for a number of typical habitats of this plant is explained by the influence of different regimes of surface waters during floods and subsurface waters during the growing season, in conditions of a wide variety of alluvial deposits along the profile of the soil aeration zone, their physical and chemical characteristics. The floodplain formation of naked licorice includes a large number of communities of various species composition, which, with varying degrees of its participation, are among the seven most frequently encountered associations. The most productive are clean malt houses formed in the central (insular) part of the lower floodplain and delta under conditions of annual flood moistening of soils. Licorice acquires the most intensive productive development, settling on non-saline floodplain alluvial meadow and meadow dark-colored granular soils of light granulometric composition, as well as on alluvial meadow sandy loam soils formed on middle flood relief elements. In these habitats, the root mass (total, wet) in the soil layer of 0.40 m can reach 22 ... 25 tons per hectare in some areas. Most often, the root mass of licorice naked along the soil profile is distributed as follows: 90% of all roots and rhizomes - in a layer of 1.0 ... 1.2 m, including 60% - in a layer of 0 ... 0.3 m, 20% - in layer 0.3 ... 0.5 m