Abstract—The spatial distribution of areas of territory used for agricultural work is of great importance for developing measures for managing territories and planning the rational use of land and water resources. As a result of the high development of land and its use for agricultural production, the timely assessment of both the condition of soils and the growing season of crops in the fields plays an important role. Because under the conditions of the study area it is possible to choose the timing of sowing, growing, and harvesting, spatial data on the location of fields for growing rice can be used to estimate the volume of water consumed for its cultivation and develop a crop rotation model for different volumes of available water based on the level of water reserves of the main crop source. Geoinformation classification of Earth remote sensing data and the use of spectral indices can be used to monitor the dynamics of rice crop formation under existing conditions. The results of geoinformation processing of satellite images is refined using field standardization methods, including photo standardization, showing the real value of reflected energy during large-scale photography and spectroradiometry, which makes it possible to determine the characteristics of the reflected energy by these objects in various spectral ranges. The results make it possible to obtain statistical data on the values of the area of plots based on 4844 measurements; the average values of the area of plots are established—0.447, standard deviation is 0.309, the maximum area is 5.84 ha, and the minimum area is 0.02 ha. The statistical results make it possible to determine on average the estimated number of plots in the territory of An Giang province, which is 442 000 fields. Thus, when deciphering images of rice fields on satellite images, local geoinformation cartographic layers of such fields are developed, taking into account the actual characteristics and stage of plant vegetation, as well as the stage of harvesting and the stage of tillage.

The phytocenotic potential of pasture ecosystems of the Tsimlyanskii sand massif using the ecological scales of humidity, soil reaction, and soil richness in mineral nitrogen of G. Ellenberg is studied. This work is based on landscape-bioecological and ecological-morphological research methods using methods for studying the structure, stability and development of plant communities. It has been established that the family types Poaceae, Fabaceae, and Asteraceae play the greatest role in projective coverage. The predominant life form of vegetation at all sites studied are is 40–71

The research purpose is to assess the mesorelief geoecological significance in the desalination and filling of the river waters of the Kazanskaya-Veshenskaya sand massif. The studies were carried out on the watercourses of the eastern (Kumylga, Khopyor, Srednaya Elan’, Sukhaya Elan’, Malaya Peskovatka, Peskovatka rivers and spring in the Shakinskaya oak grove) and western (Otrog spring and situated in Kazanskaya forestry spring; Peskovatka, Elan rivers) parts of the massif. It is established that the underground runoff is 70% of the amount runoff through open watercourses (or 89 thousands m 3 ). In October, the total daily flow through the Kazanskaya-Veshenskaya sand massif is 216 thousand m 3 . The annual groundwater supply is equal to 141.6 million m 3 . A third of this water is discharged in two spring months. The remaining 99.1 million m 3 are discharged into the groundwater during the remaining 10 months. On average, this amounts to 330 thousand m 3 per day.

This study investigated the effects of hydrological, agroecological, and soil-hydrophysical factors on the vertical subsurface flow within the vadose zone and groundwater (GW) recharge on the sand massifs in the Don Region. This involves issues of adapting lysimeter studies to field observations in investigations of the moisture transport dynamics in light-textured soils. Techniques for reconstruction of the main hydrophysical characteristics and the scaling were employed to simulate moisture transport under various initial and boundary conditions. Laboratory investigations were performed at the Hydrological Complex of the Federal Scientific Centre of Agroecology of the Russian Academy of Sciences; field studies were conducted on the Eterevsky sand massif in Volgograd Oblast. The reconstructed hydrophysical parameters and HYDRUS-1D program revealed the effects of different soil–plant conditions on GW recharge. The open sands have an inflow to GW throughout the year, which ensures a stable supply to the river systems. The grounds occupied by herbaceous plants and pine plantations on soils with low water holding capacity, are the supplementary source of GW recharge. The volume of the gravity flow from the vadose zone to GW was established to depend entirely on the biomass of the herbaceous plants on the sands and the quality (bonitet) of the forest plantations.

The research purpose is a comprehensive assessment of the Middle part of the Don river sand massifs soil and hydrological conditions. The research objects are the sandy massifs of the Middle Don on an area of 527 thousand hectares. The sand arenas water balance dynamics for the period from November to March and for the period from April to October has been revealed. It has been established that atmospheric precipitation is the main source of river water supply. The basis of river systems flood filling are clay soils that form an intra-soil runoff. The low water period level is supported by sandy soils. A decrease in the density of plant formations contributes to an increase in groundwater supply. The total underground runoff reaches 599 million m 3 from the sandy massifs of the Middle Don. The volume and dynamics of the moisture movement in the soil depend on the system of sandy areas use. Therefore, the load on sandy arenas should be regulated. Pasture farming should remain the dominant form of sand use. An effective method of sandy arenas afforestation is the planting of pine plantations according to the savanna type.

Common hazel is valuable for its nutritional and medicinal properties and its ability to provide soil conservation functions. However, the morphological characteristics of this plant have not been studied sufficiently. The research purpose is to identify features of significant morphological characteristics of crowns of nut-bearing hazel plants, to assess the biological diversity of these characteristics at different heights, under the forest canopy and on the glades for further detection of forestry and ecological functions of this plant, and to select ornamental and other economically valuable forms. The nut-bearing hazel plants growing in the mountain forests of the North-Western Caucasus at the altitude of 450–600 and 1,300–1,500 m above the sea level under the forest canopy and on the glades were the objects of the research. We studied the diameters of the central and three largest trunks, the crown and the base of the bush, its height, the number of shoots up to 4 years old and older, the total number of shoots in the bush, the density and shape of the crown. We examined 200 ramets that had entered the fruiting stage. The diversity index was calculated according to the authors’ method (Sukhorukikh-Biganova). At the altitudes of 1,300–1,500 m above the sea level, under better humidification compared to the sites located at the altitude of 450–600 m, hazel has statistically reliable better development of average diameters of the central and three main trunks and crown, higher total number of shoots up to 4 years old and older. Hazel trees have superior crown and bush base diameters, greater number of shoots up to 4 years old and older, the total number of shoots in the bush on the glades in conditions of good light compared to those under the forest canopy. Here the plants are more likely to form bushes with a spreading and thick crown. The upper sites showed a significantly higher diversity index for the average diameter of the three largest trunks of the hazel bush and the highest number of shoots older than 4 years. There is a significantly superior difference in the morphological diversity index for the average diameter of the bush base, the number of shoots up to 4 years old and older, the total number of shoots, and crown density on the glades compared to the sites under the forest canopy. In terms of crown shape, the diversity index is higher under the forest canopy than on the glade. The generalized indices of diversity of quantitative, qualitative and general morphological characteristics of hazel bushes did not differ significantly at different heights, under forest canopy and on the glades.

Under conditions of an arid climate and insufficient moisture supply for plants, the study of soil and the hydrological features of sand massifs becomes relevant. The purpose of this study was to investigate water regime types in sand massifs of the Don River basin. During 2003–2021, route and stationary (laying out of water regime sites) surveys were arranged on the territory of sand massifs of the river and its tributaries. Laboratory studies were carried out at the hydrological complex of the Federal Scientific Center of Agroecology of the Russian Academy of Sciences, which included eight large lysimeters and 18 vegetation sites. Infiltration in open sands reached 70% of the annual precipitation volume on average. The maximum runoff to the groundwater was observed for sand massifs of the Upper Don. According to lysimetric studies, the average annual intensity of the groundwater runoff under black fallow conditions was 0.73 mm/day for sand soils (the highest value), 0.65 mm/day for sandy loam soils, and 0.37 mm/day for loamy soils. At the same time, in the second half of the year, sandy loam soils were able to discharge more water into the groundwater than sandy and loamy soils. A nonflushing water regime was observed mainly on the third terrace of sandy massifs characterized by deep groundwater occurrence (>8 m) and soils with a heavy granulometric composition. Daily fluctuations of the groundwater level with the general decrease of this index were observed in the areas, where groundwater was available for tree roots, since the night water inflow did not compensate for transpiration water flow. The seasonal fluctuations of the groundwater level in the sands of the Don basin areas were 40–60 cm on average, but can also reach 90 cm.

Green plantings in the urban environment form a natural carcass, increase environmental protection functions and create comfortable living conditions for the population. Research is relevant due to the fact that monitoring the state and conditions of green plantings growth is a prerequisite for timely adoption of measures to restore and maintain the proper functioning of urban natural-anthropogenic systems. The aim of the research is to assess the current state of landscaping objects in the city of Volzhsky. The plot with cadastral number 34:35:000000: 66118 has about 20% of dying trees, most of which are old-growth stands. Young and mature trees Populus nigra and Salix alba are in good condition. On the territory of the park (cadastral number 34:35:030121:201) >40% of trees are weakened or slightly damaged. The share of withering and withered trees reaches 27% of the total number of trees. Fraxinus excelsior is in the worst condition. 59% of Populus nigra trees dry up. In the park (cadastral number 34:35:030213:246) the forest stand and lawn cover are in excellent condition. The roadside forest belt (cadastral number 34:28:000000:2955) cannot fully fulfill its ecological functions and does not meet economic goals.

Remote monitoring and landscape–environmental profiling of the Archeda–Don sand massif made it possible to assess the state of the soil–vegetation cover and to determine the groundwater level and inclination. The degrees of soil salinity were identified for various sand types. The salinization of chernozem-like soils reaches 0.05%. The salinization of sand massifs with large amounts of litterfall is 0.05–0.07%. In open sands that formed in depressions as a result of blowing, the salinity does not exceed 0.001%. Pine outliers and planted stands are widespread throughout the sand massif. Natural forest stands consist of the following species: Betula pendula, Alnus glutinosa, Quercus robur, Populus tremula, and Salix spp. (S. fragilis, S. reptans, S. carpea, and S. rosmarinifolia). Pinus sylvestris plantings were introduced in the 19th century. The large number of forest sites and their outlier-based distribution are determined by the proximity of groundwaters. Black alder (Alnus glutinosa) stands reach the maximum productivity with a timber volume of up to 500 m3/ha. In areas with stagnant groundwaters, their height is 12–15 m. Birch (Betula pendula) outliers are located in depressions. Sparse European oak (Quercus robur) standing 8–12 m high occur on clayey sites. It is shown that Pinus sylvestris grows optimally on chernozem-like sandy loam soils and on single-phase, overgrown sands with thick, sod–steppe soils. Five dominant types of sands have been distinguished. The total area of forage lands within the sand massif is 171 536 ha; their herbage productivity is 370 700 t. The total area of forest sites is 50 584 ha. Overgrown hummocky–ridgy sands predominate. Overgrown closed depressions and ancient watercourses feature the highest productivity (3.0 t/ha). The results are essential for the development of a conceptual model for the optimal use of sandy lands.

Water balance studies have been carried out in the territory of sand massifs in the Don River Basin. The studies were mostly focused on the water-regime plots in Kalachevsko-Golubinskie and Archedinsko-Donskie sands. The area under study was divided into zones according to sand types based on land relief, the conditions of the soil cover, vegetation, and phreatic-water mineralization and level. Water-balance parameters and the characteristics of water regime were evaluated for individual types of sands. The volume of gravity flow of precipitation into the Don river system was determined. The study suggests the important role of sand massifs in water-resources protection, which consists in water freshening and maintaining river discharges.

One of the most significant issues in common hazelnut biology and selection is the diversity (polymorphism) assessment of its fruits and the occurrence prediction of its forms with economically valuable features in natural populations, which are the source of the most valuable gene pool of the species. The research purpose is to identify the hazelnut diversity and to predict the occurrence of its forms in natural oak and fir forest formations of the studied region. For analysis, one nut was randomly selected from each plant of oak (297 pcs.) and fir (301 pcs.) forest formations. We studied the main economically valuable parameters of hazelnuts: kernel weight and yield, nut weight, fruit quality total score, nutshell strength and color, taste, indestructibility and presence of husk on a kernel. The significance of differences in entropy, its dispersion and degree of freedom, diversity by the Shannon index, variation coefficients, chi(2) values, Pearson and Chuprov coefficients were determined by known methods. The index of distributed rank diversity (IRRR) was calculated from the ratio of the sum of the products of the relative entropy of a feature by its rank to the number of scales of this feature. The index of distributed rank diversity including share (IRRRD) for a single feature was defined as the product of the IRRR by the share of the feature of the corresponding scale. The forecast of the presence of hazelnut forms is made according to the law of parallelism. It was found that hazel has nuts with similar features in oak and fir forest formations. The conclusions on a greater variety of parameters of hazel fruits, growing in the composition of oak forest formation, in comparison with fir forest formation coincided completely with the Shannon index, IRRR, IRRRD and chi(2). The occurrence of the most economically valuable forms in forest formations is predicted with varying frequency.

Транспирационный коэффициент (ТК) меняется в процессе жизненного цикла растений и показывает отношение растительности к условиям водообеспеченности мест произрастания. Наиболее активно расходуется вода в период нарастания вегетационной массы. В период созревания репродуктивных органов ТК уменьшается. Объектом исследований являлись естественные и искусственные фитоценозы, произрастающие на гидрологическом комплексе ФНЦ агроэкологии РАН (г. Волгоград), а также на ключевых участках Арчединско-Донских и Усть-Кундрюченских песков. В 2016 г. на гидрологическом комплексе ТК определялся исходя из сформированной на лизиметрах естественной растительности. На песке: Agropyron repens L., Erigeron canadensis L., Polygonum aviculare L., Bromus arvensis L., Galium aparine, Chenopodium album L., Chenopodium album L., Lactuca serriola L.; урожайность при этом была 2,1 т/га. ТК в этом случае составил 610. На легком суглинке (каштановая почва) произрастали: Lactuca serriola L., Erigeron canadensis L., Polygonum aviculare L., Bromus arvensis L., Agropyron repens L., Chenopodium album L., Taraxacum officinale, Galium aparine; урожайность составила 4,2 т/га. ТК в этом случае – 498. ТК биомассы яровой пшеницы сорта Камышинская-3, посеянной в апреле 2017 г. на лизиметрах ФНЦ агроэкологии РАН с легким суглинком (каштановая почва) и мелкозернистым пылеватым песком, составили соответственно 493 и 515. Исследования показали, что транспирационные коэффициенты, рассчитанные по биомассе яровых культур, существенно выше озимых. Отсюда следует целесообразность по возможности смещать вегетацию культур в засушливой и острозасушливой зонах на осенневесенние периоды. Это позволяет в наиболее засушливые месяцы (июль-август) исключать вегетацию или экономить влагу, когда у растений минимальный вегетативный аппарат.

Исследования на землях Чирского песчаного массива проводились на II надпойменной террасе. Были выявлены особенности видового состава, структуры и запаса надземной фитомассы степного комплекса фитоценозов, нагрузка на песчаные земли с учетом кормовой емкости. Геоботаническое обследование и оценка растительного биоразнообразия проводились на ключевых участках различных по степени зарастания (открытые или слабозаросшие, среднезаросшие и заросшие пески). Выявлено, что основную долю в фитомассе занимают кормовые виды (на открытых песках – 42,8 %, на среднезаросших песках – 58,8 %, на заросших песках – 52,3 %) и лекарственные виды (на открытых песках – 38,0 %, на среднезаросших песках – 35,38 %, на заросших песках – 33,3 %). Доля рудеральных видов в составе сообществ составляет 5,914,3 %, доля ядовитых трав – 4,8-11,8 %. Наибольшее количество видов в сообществах относится к семейству Asteraceae (Cirsium arvense L., Scorzonera humilis L., Campestre L., Helichrysum arenarium L., Artemisia austiaca Jacq., Senecio vulgaris и др.). Основную фитомассу в составе фитоценозов составляют одно-, двуи малолетние виды. Экологический анализ видового состава растительных сообществ позволил выявить растения-индикаторы, указывающие на микроклиматические особенности природной среды. Установлено, что на всех типах песков доминируют мезофиты. На открытых и заросших песках их доля составляет 52 %, на среднезаросших песках – 47 %. Охраняемых таксонов и популяций на территории II террасы песчаного массива не зафиксировано. Наибольшую нагрузку скота могут выдержать кормовые угодья Чирского песчаного массива на заросших песках в весенне-летний период (0,9-1,0 гол./га), а наименьшую нагрузку переносят пастбища на открытых и слабозаросших песках во все сезоны использования (0,2-0,4 гол./га). Таким образом, на песчаных массивах исследуемых участков нагрузка животных должна равномерно снижаться от весны к осени и варьировать от 0,2-0,4 гол./га до 0,5-1,0 гол./га в зависимости от степени зарастания песков.

The pasture ecosystems of semiarid zones of Russia within the Sarpa Lowland were monitored, and regional problem were revealed. The experimental data were obtained in 1999–2017. It is established that the current state of agricultural landscapes is critical. The portion of degraded pastures is more than 600 000 ha (34%), and more than half of them are characterized by strong degradation. The total area of forage lands in the region is about 1 870 000 ha, 35–40% of which are moderately degraded pastures, 30–40% are strongly degraded pastures, and 15–20% are lands excluded from agricultural use (degraded sands or abandoned lands). The digression is greatest on winter (year-round) pastures. The area of bare and blown sands has increased to 20–30%. The load on pastures in some areas exceeds the optimal layer by five to seven times. Almost all pastures need rest and agronomic restoration measures. Desertification, which results in salinization, erosion, and deflation, is a great environmental problem in the region. The loss of pasture productivity as a result of desertification in the region is 1 052 700 centners of fodder units (CFUs) per year. Agroforestry measures are very important for the prevention of soil erosion and deflation and are considered to be a multifunctional, long-term factor of environment protection. We compiled a map of forest-growing conditions for ecologically and economically efficient forest reclamation. It is based on the forest reclamation classification, which reflects the natural parameters of the area and specific features of its forest reclamation.

Aim. Evaluation of species diversity and ecological and phytocenotic organization of psammophytic communities of the grass-shrub layer of the Tsimlyanskiy sandy massif, Rostovskaya Oblast and Volgogradskaya Oblast, Russian Federation Material and Methods. Generally accepted methods in environmental-geobotanical surveys were used. Species composition and yield of phytocenoses, dominant species and relative percentages of species in the phytomass were determined and vegetation groups were identified with respect to soil moisture and to nutrition. Results. 69 species from 17 families were identified. The largest number of species is from the Asteraceae (18), Poaceae (15) and Fabaceae (12) families. In terms of classification in relation to moisture, the largest numbers of species were xeromesophytes (30) and xerophytes (23). Species saturation was assessed as 3-6 species per 1 m 2 . The vegetation of the massif is azonal with a tendency in the direction of decreasing xerophyticity and the intrusion of meadow-bog and forest communities. As regards classification according to nutrition, of the total number of species, the largest number was of meso-trophs (41). In the communities of sandy steppe II terraces grains dominate (66.5%) with the proportion of grasses being 33%. Here 16 species were identified with a high proportion of the herbs Agropyron pectinatum (Bieb.) Beauv., Elytrigia elongata (Host) Nevski, Festuca valesiaca Gaudin, F. beckeri (Hack.) Trautv., Poa pratensis ssp. pratensis and Stipa capillata L., S. pennata L. Conclusions. The Tsimlyanskiy sand massif is characterised by regionally bo-tanico-geographic specific vegetation. In the flora, there are typical hemip-sammophilous and psammophilous species with a dominance of cereals -characteristic of the regional soil and climatic conditions. The species composition of communities varies depending on the landscape-ecological conditions.

Mathematical modeling and computational experiment of the soil-plant systems (SPS) ecology are forming the basis of analysis and prediction scientific paradigm of more complex ecosystems. The dynamics of processes occurring in open biological systems and phenomena occurring in inorganic environments are comparing in this research. The behavior of systems of biotic and abiotic origin has bifurcation points associated with the nonlinear nature of interaction between the external environment and the elements inside, predetermining the synergy of evolution. During the studying SPS using the example of the Black Lands of the Republic of Kalmykia, a mathematical model of multichannel transitions between elements was developed using the Markov process mechanism. The dynamics of the SPS ecotope destruction and recovery was studied in the approximation of homogeneous Markov chains. Stationary final distributions of the comparison of classes derived from matrices with high degrees revealed bifurcation points, the nonlinearity of the succession process. Mathematical modeling gave the lifetime of an intermediate states stable existence. As a result, the methodology for assessing the ecological status of arid ecosystems using Markov chains has been proposed. The analogy with inorganic systems allowed detailing the process of the origin of bifurcation points. Comparison of the dynamics of open systems «living» and «inanimate» nature has led to their synergistic unity. Nonlinear processes in inorganic environment are qualitatively similar to the dynamics of macroscopic systems in ecology.