Canola cultivation at high latitudes is becoming more promising in terms of modern climate change. Sustainable crop production requires an understanding of yield-limiting factors, which need to be adjusted in agricultural management first. Therefore, our study was aimed at examining the effect of climate and soil fertility factors on the canola yield from 2012 to 2015 in northwestern Russia. Simultaneously, effectiveness of chemical fertilizer (N${}_{65}$P${}_{50}$K${}_{50}$ and N${}_{100}$P${}_{75}$K${}_{75}$) rates was tested. Studied soils had light texture, high acidity and severe sulfur deficiency. Canola yield (Y) varied from 0.81 to 1.60 t·ha${}^{-1}$ for the observed period. Applied fertilizer increased Y by around 30%, but this change was not significant. Climate effect testing with the FAO-AquaCrop simulation showed no noticeable water and heat stresses for the study period (0% to 20% reduction in potential Y). Among the tested soil properties, the content of organic carbon, available nitrogen and sulfur significantly correlated with Y (r = 0.58–0.66). Combining these factors together with soil pH in a path model explained 60% of variability in Y. Importantly, sulfur had the highest and most significant effect in this model. Thus, this soil parameter is the main yield-limiting factor in the study area, which must be the first to be adjusted in agricultural practice.

In semi-arid ecoregions of temperate zones, focused snowmelt water infiltration in topographic depressions is a key, but imperfectly understood, groundwater recharge mechanism. Routine monitoring is precluded by the abundance of depressions. We have used remote-sensing data to construct mass balances and estimate volumes of temporary ponds in the Tambov area of Russia. First, small water bodies were automatically recognized in each of a time series of high-resolution Planet Labs images taken in April and May 2021 by object-oriented supervised classification. A training set of water pixels defined in one of the latest images using a small unmanned aerial vehicle enabled high-confidence predictions of water pixels in the earlier images (Cohen’s Κ = 0.99). A digital elevation model was used to estimate the ponds’ water volumes, which decreased with time following a negative exponential equation. The power of the exponent did not systematically depend on the pond size. With adjustment for estimates of daily Penman evaporation, function-based interpolation of the water bodies’ areas and volumes allowed calculation of daily infiltration into the depression beds. The infiltration was maximal (5–40 mm/day) at onset of spring and decreased with time during the study period. Use of the spatially variable infiltration rates improved steady-state shallow groundwater simulations.

The observed climate changes and increasing groundwater levels in the forest-steppe region should be reflected in the water regime of meadow-chernozemic soils (Gleyic Chernozems). This article analyzes the seasonal dynamics of volumetric moisture content in a fallow Gleyic Chernozem (Siltic, Hyperhumic, Pachic) and two arable Gleyic Chernozems (Siltic, Aric, Hyperhumic, Pachic), as well as the level of groundwater in the Tokarevskii district of Tambov oblast during the period from fall 2022 to summer 2023. The obtained data are compared with regime observations of volumetric moisture content and groundwater levels in these soils performed in 1969–1971. The use of automated monitoring systems for the soil moisture content and groundwater levels has allowed continuous data collection on soil moistureand detailed tracking of seasonal changes. The fallow meadow-chernozemic soils is characterized by higher moisture levels compared to arable soils; the upper horizons of cultivated soils are characterized by a higher frequency of wetting–drying periods and a shorter continuous duration of these periods, which is confirmed both by moisture monitoring data and by the morphological features of the soils, such as the form of carbonate pedofeatures and the depth of their detection. During the observation period in 2022–2023, the meadow-chernozemic soils were relatively dry, despite the higher than normal annual precipitation. Wilting point moisture in the top 20-cm layer of cultivated soils was established from March 2023, and in the fallow soil, from the end of April 2023. Periods with the moisture content exceeding the field capacity within the 60-cm-thick upper soil layer were not observed during the entire observation period. The soils were drier than in the dry year of 1972, when the moisture content was less than the wilting point in the upper part of the profile from June to September. In the wet years of 1969–1970, the moisture content did not drop below the wilting point in the upper 20-cm layer throughout the observation period. The main reason for this difference in the moisture content is the change in the groundwater level: in 2022–2023, the groundwater level was more than 4 m deep, whereas in 1969 it did not go deeper than 2 m, and in 1971, deeper than 4 m. As a result, the soil’s uptake of moisture through capillary rise did not occur in 2022–2023, and the water regime of the meadow-chernozemic soils more closely resembled the water regime of typical chernozems (Haplic Chernozems).

Understanding the spatial variability of soil organic carbon (SOC) content and its functional pools under current farming practices is crucial for developing targeted C management. This study quantified and predicted the farm-scale variability of SOC pools across conventional tillage (CT) and no-tillage (NT; 8–14 years) practices at two sites (Rostov and Krasnodar) in Russia. The soil types at Rostov and Krasnodar farms were Calcic Chernozem (sunflower–wheat rotation) and Stagnic Chernozem (maize–wheat rotation), respectively. The average SOC content at the Rostov site was higher than the Krasnodar site by 41% and 28% in 0–10 and 10–30 cm, respectively. For both sites, there was no clear trend in SOC variability between NT and CT practices. However, topsoil microbial-available C pool (mineralized for 180 days) was most sensitive to tillage systems, unlike unchanged particle-size C pools. Specifically, it increased from CT to NT at the Rostov site (by 7–16%), but it showed a decreased trend at the Krasnodar site (by 11–29%). Gradient boosting machines statistical models with remote sensing data based explanatory variables (spectral, topography) accurately predicted the spatial distributions of topsoil C content (R² = 0.99) and its microbial-available pool (R² = 0.78) across the farmland areas. The main explanatory variables included topography, vegetation distribution, moisture and thermal regimes. For both sites, DNDC modeling showed that applying NT versus CT for 30 years could potentially increase SOC in the topsoil by 27–28% and decrease it in the subsoil by 6–9% (sunflower–wheat–maize–wheat rotation; annual N and P rates of 41–80 and 0–52 kg ha⁻¹). This study provides insights into current agricultural challenges and the developing site-specific strategies for managing soil C accrual in the Chernozem region.

Creating an optimal light environment for different crops is crucial for achieving high yields under controlled environment agriculture conditions. Currently, there are no optimal technologies, including lighting technologies, for growing root crops (in particular radish) in CEA (Controlled Environment Agriculture). This study examined the effects of HPS (High-pressure sodium vapor lamps) and three original sunlike full-spectrum LED lamps on the morphophysiological characteristics and the diffuse reflectance indices of the leaves of two contrast radish cultivars. It was found that a higher blue light content (24%) in the spectrum of the LED 3 lamp contributed to the formation of radish plants with a more compact leaf rosette and maximum yield of roots (up to 19%) compared to the other two types of LED lamps. When treated with LED 3, photosynthesis efficiency was probably higher compared to LED 1 and LED 2, which led to a significant decrease in reflected radiation, especially in the blue and red ranges (by 5–143% and 32–86%, respectively). It was found that the genotype had a significant effect on all morphophysiological parameters of radish, while lighting treatment only affected the integral parameters (Pr—proportion of root crop, and Ai—attraction index) and leaf thickness. However, lighting treatment exhibited a greater impact on leaf reflection indices compared to the genotype, especially those related to chlorophyll content. The results of the study indicate that LED 3 lamps, simulating natural light at midday, are suitable for the production of radish root crops under CEA conditions.