Application of DSS in agroecological assessment of the potential of use of chernozem soils in the conditions of the Penza region

. The paper discusses the use of a decision support system (DSS) for the purpose of automated agroecological assessment of chernozem soils of the Penza region in comparison with the agroecological classification of soil cover based on standard agrochemical characteristics. The results show the rationality of using DSS, as well as the increased agroecological potential of the analyzed old arable field. Calculations made it possible to identify limiting soil-ecological parameters, such as insufficient content of mobile forms of phosphorus and the density of the arable soil horizon, as well as to calculate the soil-ecological quality rating both for the entire field and for a regular hectare grid.


Introduction
The widespread introduction of digital agriculture has a number of advantages, including increasing yields, improving agricultural risk management, strengthening the overall food security of the country, and introducing technologies for automated decision support systems using big data and cloud computing.In addition to the above, digitalization of agriculture helps reduce costs, improve product quality and increase labor productivity, contributing to sustainable development and environmental conservation through preliminary process modeling in order to optimize the use of technological and agrochemical techniques and operations [1,2].
One of the areas whose digitalization in agriculture can occur in the shortest possible time is agroecological assessment of land.Despite the relevance of the use of digital solutions in the industry, the market for software for assessment systems in our country is still not developed and is represented mainly by single developments [3], the ideology of which was laid in the early 2000s and algorithms -additions to GIS, and more often just calculation formulas [4].
The paper examines the possibility of using the DSS "RASKAZ" for the purpose of automated agroecological assessment of old arable lands, carried out on the basis of a preliminary agroecological classification of soil cover.
The purpose of the work is to adapt the framework system of the Regional Agroecological Land Assessment to the typical conditions of chernozem soils in the Penza region.

Materials and methods
The research was carried out in 2017-2023 on the territory of the M-12 commodity field of Bashmakovsky Bread JSC, Bashmakovsky district of the Penza region.The field of 100 hectares is represented by thick humus heavy loamy leached chernozems on moraine loams and is the top of a flat watershed.The exposure of the slope is southern, the slope is uniform, gentle up to 2°.There is an increased spatial heterogeneity of microrelief forms, represented by forms of suffusion processes -saucers and depressions.At the southeastern end of the field there are erosion processes (Fig. 1) based on two depressions that are part of the hydrographic network.Runoff furrows and gullies are observed.In the northern part of the field, areas of crop wetting were identified, associated with the nature of intrasoil runoff and gley formation processes [5].The field area was divided into a regular 100-meter sampling network with samples taken from the network's nodes.Sampling was carried out once a year after harvesting crops before the main soil fertilization.
Chemical analyzes were carried out at the laboratory of the LAMP RSAU-MTAA according to standard methods of TsINAO.As a result of chemical analyses, the following were determined: ammonium nitrogen, nitrite nitrogen, exchangeable potassium, mobile phosphorus, total sulfur, C-organic sulfur, hydrolytic acidity, pH of aqueous extract, pH of salt extract.The soil density was determined directly in the field using the penetration method using an Eijkelkamp pointer penetrometer [6].
The data obtained as a result of the analyzes were statistically processed using the basic capabilities of MS Excel.Data distributions were visualized by GS Surfer in the form of maps with smoothing using the kriging method.
The use of the Regional System of Integrated Agro-Ecological Land Assessment to improve the accuracy of the overall assessment and get rid of the "diversity" of the obtained results required reducing the number of points and expanding the set of parameters being assessed.As a result of preliminary adaptation of the data, the field was divided into 10 , 020 (2024) BIO Web of Conferences MSNBAS2023 https://doi.org/10.1051/bioconf/2024820200404 82 analyzed areas with 10 sampling points in each.The number of parameters assessed was increased through the use of data from the FSBI GSAC "Penzensky", which conducted a survey of the lands of JSC "Bashmakovsky Bread" in 2017, including the field under study [7].To fill the database of agroecological parameters of the analyzed field from the Agrochemical passport, the following data were used: soil mechanical composition, total nitrogen, sum of absorbed bases, degree of saturation with bases, bases, microelements and heavy metals (Ca, Mg, B, Cu, Zn, Mo, Pb, Cd, Hg, As).

Result and discussion
The developed database made it possible to carry out a preliminary grouping of soils [8] according to the provision of basic nutrients and additional agro-ecological parameters (Table 1).51% of the arable horizon of the soil cover of the field under study belongs to the area with a high humus content [9] and only 10% can be classified as low in organic matter.Most of the analyzed territory in terms of ammonium nitrogen supply (73%) is characterized as average in supply, with 25% having low and very low supply of soils, located mainly in eroded areas.

Fig. 2. Partial representation of the current soil characteristics database
Grouping soils according to the content of mobile forms of phosphorus showed a uniform distribution of territory between low and very low content of the macroelement.Metabolic forms of potassium are contained in the arable horizon in a significant volume and 72% of the territory is characterized as highly supplied with potassium.
The assessment of soil acidity showed a general (94%) slightly acidic reaction of the environment (pH 5.1-5.5)without temporary variation in the indicator, which is typical for leached chernozems of the Penza region.
At the next stage, comprehensive agroecological assessment of the potential for soil use was carried out using the computing capabilities of the modernized DSS "RASKAZ" (Regional Automated System for Integrated Agroecological Land Assessment), previously zoned to the conditions of the Penza region.Detailed characteristics for 36 parameters identified at the initial stage of the field assessment sites were entered into the bank of current soil characteristics (Fig. 2), which, based on the parameter significance matrices, Automated calculations made it possible to assess in detail the diversity of soil fertility parameters, to identify main diagnostic and limiting parameters, distributed territorially and additionally classified into six assessment groups: overall land productivity, physical soil conditions, spatial homogeneity of the physicochemical requirements for reclamation, natural soil resistance to pollution and the general sanitary and ecological condition of the lands (Fig. 3).

Fig. 3. General view of the result of the analysis of the complex agro-ecological state of one of the field sections
The general agroecological condition of the entire territory of the analyzed old arable field is assessed as "Good" with the soil-ecological quality of leached chernozems SAB 80±2 points.The minimum quality score SAB 78 was detected on the site of eroded soils at the southern end of the field at five sampling points out of 100.The average quality score corresponded to 79% of the surveyed territory.The highest SAB score of 82 was scored by the soils of the top of the watershed hill at the southern end of the field.
Land productivity was assessed by the content of macro-and microelements, as well as Corg, in the arable horizon.and the thickness of the humus layer was assessed as "Average".The productivity assessment fully correlated with the soil-ecological quality of , 020 (2024) BIO Web of Conferences MSNBAS2023 https://doi.org/10.1051/bioconf/2024820200404 82 the field (K 0.89±0.12)and made it possible to identify a group of limiting and unstable (main diagnostic) parameters.Thus, on soils with maximum SAB in the absence of a limiting parameter, the content of exchangeable forms of potassium was unstable; the assessment of availability using DSS was 0.92, which corresponds to 92% of the standard content for leached chernozems in the study region [6].The productivity of 68% of the predominantly central part of the field was limited by the content of mobile forms of phosphorus (DSS -0.4 ± 0.05); the same Рpodv was identified as unstable.In isolated cases, on 5% of the total field area, the program identified mobile Mn as an unstable productivity factor (DSS -0.8±0.1).
Field cultivation conditions are rated as "Good" with a widely identified unstable factor -soil density (DSS -0.9±0.07).In the eroded northern part of the field, soil density is additionally determined as a limiting factor (SPPR -0.65±0.04).
The spatial homogeneity of the territory was classified by the system of integrated agroecological assessment as "Homogeneous" with the limiting parameter -K exchange (DSS -0.9±0.05).Reclamation requirements were not identified.
The resistance of the field territory to pollution [7] using RASKAZ is assessed as "High" with a limitation of 62% of the territory in the central and southern eroded parts of the field by absorption capacity (DSS -0.77±0.03);also in the southern end of the field it was determined an unstable parameter that directly affects the possibility of soil contamination is bulk density (DSS 0.93±0.02).The sanitary and ecological condition of the territory of the analyzed old arable field is assessed as "Prosperous" without limiting parameters.

Conclusion
The results of the study conducted using the DSS "RASKAZ" highly correlate with the classical typification of the territory and characterize the potential for the use of an oldarable commercial field as "Increased" (SAB 80±2) with the identification of a common limiting parameter -mobile phosphorus, the deficiency of which is typical for leached chernozems of the Bashmakovsky district of the Penza region.A slight lack of metabolic forms of potassium, taking into account the fact that the leached chernozems of the study area initially have a high supply of this nutrient and low phosphorus content, clearly indicate the need to use complex forms of fertilizers in order to maintain a positive balance of nutrients in agroecosystems.An unstable parameter that requires additional attention is the density of the structure, which we associate with the gradual natural destruction of the structure [8] and over-compaction of the upper arable horizon of the field as a result of agrotechnical operations for the cultivation of agricultural crops.

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020 (2024) BIO Web of Conferences MSNBAS2023 https://doi.org/10.1051/bioconf/2024820200404 82 was checked by the program with reference values characteristic of leached chernozems, as well as a regionalized database of average soil values characteristics of the study region.

Table 1 .
Provision of the arable horizon with organic matter and macroelements