Soil Fertility Levels Research Articles

Residual Carbon Derived from Different Maize Parts Differed in Soil Organic Carbon Fractions as Affected by Soil Fertility

Maize straw returning is one of the important measures to improve dryland soil organic carbon (SOC). However, the effects of different maize parts on SOC fractions with different soil fertility levels in situ are not exactly clear. Therefore, an in situ field incubation experiment over 540 days, by adding different 13C-labeled maize parts (root, stem and leaf) into low- (no fertilizer treatment) and high- (manure treatment) fertility soils, was conducted at a long-term brown earth experimental site in Shenyang of China to figure out the effects of different maize parts on SOC fractions (dissolved organic carbon (DOC) and particulate organic carbon (POC)). The results showed that the distribution–DOC ratio of low-fertility treatment was higher than that of high-fertility treatment in the period of rapid decomposition of straw. In both low- and high-fertility soils, the ratio of carbon to DOC in leaf residue was higher than that in root and stem residues. The proportion of root, stem and leaf residue converted to DOC in low-fertility soil was 4.51%, 3.89% and 5.00%, respectively. The proportion of root, stem and leaf residue converted to DOC in high-fertility soil was 4.10%, 3.65% and 4.11%, respectively. As for the distribution–POC ratio, during the period of rapid decomposition of straw, the ratio of carbon conversion from root and stem residue to POC was generally higher than that from leaf residue. The ratio of carbon conversion to POC of root, stem and leaf residues in high-fertility treatment was higher than that in low-fertility treatment. In low-fertility treatment, the proportion of root, stem and leaf residues converted to POC was 41.34%, 46.33% and 36.11%, respectively. The proportion of root, stem and leaf residue converted to POC in high-fertility soil was 46.48%, 44.45% and 41.14%, respectively. The results showed that, for DOC, a low fertility level and more leaf residue types were beneficial. While, for POC, root and stem residues with a high fertility level were beneficial. These results provide evidence that the addition of different parts of maize residues would have differing effects on DOC and POC. Leaf residues in low-fertility soils were more suitable for increasing DOC. Root and stem residues in high-fertility soils were more suitable for increasing POC. Nevertheless, we could not ignore the unmeasured SOC fractions that some of the residues could be converted to.

The Soil Diagnostic Method to Formulate Fertilizer Requirements for Coffee Trees in Côte d'Ivoire

Coffee is a crop that exports significant amounts of minerals from the soil, particularly through crop and pruning products. Maintaining sustainable productivity requires good knowledge and rational management of factors related to soil fertility and plant nutritional status, which would limit production. The objective of this study was to diagnose the mineral requirements of coffee plants in different production regions in order to recommend nutrient quantities adapted to the characteristics of each soil type for sustainable coffee production. Chemical analysis of 156 soil samples representative of the soil units of the coffee growing areas using a soil diagnostic model specific to coffee fertilization was used to determine the nutrient requirements of each soil unit studied. The results generally indicate that soil fertility levels were below the reference threshold values. Nutrient inputs are essential for all soils under coffee in large production areas. Nitrogen inputs are required in all soil units studied. The majority of the soils also showed a very pronounced potassium and calcium deficiency, while the phosphorus deficiency was not very pronounced. Magnesium, although generally in sufficient quantity in soils, has been readjusted to respect the balance in exchangeable bases. The amounts of nutrients to be supplied varied from one soil unit to another. Soils with low organic matter content showed relatively high requirements. Recommendations for appropriate soil fertility management per soil unit were presented in this work.

Mycotrichocompost and biochar addition on lead (Pb) content in the ex-gold mining soil for corn plant (Zea mays L.)

Gold mining land has a low level of soil fertility. One of the to increase soil fertility is the addition of micro-compost and biochar. Mycotrichocompost contains organic material enriched with microbes in the form of mycorrhizal fungi and Trichoderma therefore the organic compounds can bind to metal content. Biochar and together with organic matter can increase soil productivity as well as the retention and availability of nutrients for plants. The purpose of this study was to obtain the dose composition of mycotrichocompost and biochar in the binding of lead Pb content in ex-gold mine soil for corn planting. This research was carried out from June to September 2022. The study used a randomized group design which consisted of 2 treatments, mycotrichocompost treatment (0 tons ha−1, 5 tons ha−1, and 10 tons ha−1) and Biochar treatment (0 tons ha−1, 4 tons ha−1, 8 tons ha−1and 12 tons ha−1). The observed variables were Pb content, plant height, leaf length, number of leaves, leaf area index, and chlorophyll content. The results showed that mycotrichocompost and biochar addition showed an effect on Pb concentration, leaf length, and chlorophyll content. However, there was no relation between plant height and Leaf Area Index. This study concludes that the best treatment combination for Pb content is A3B2, leaf length is A3B2, and chlorophyll content is A3B2.

Competitive skill of Paspalum virgatum L.e o Panicum maximum cv. Mombaça in different soil fertilities

This work aimed to study the competitive ability between Paspalum virgatum L. and Panicum maximum cv. Mombaça in different soil fertilities. Three independent experiments were set up in a completely randomized design, with four replications. Each experiment corresponded to different levels of soil fertility (low, medium and high) and were arranged in a substitutive series in the proportions of 100:0, 75:25, 50:50, 25:75 and 0:100% of Panicum maximum cv. Mombaça with Paspalum virgatum L. The height, number of tillers and the dry matter mass of the plants were determined 60 days after the emergence of the species. Data were analyzed using the graphical analysis method, constructing diagrams based on productivity or relative and total variations, determining the competitiveness indices (CR), grouping coefficient (K) and relative aggressiveness (A). For the three fertility levels of the soils studied, the crop was superior to the competitor in terms of height, tillering and dry matter accumulation in the proportions of equivalent population densities (50:50), proving greater competitive ability through relative competitiveness values greater than 1 and crop aggressiveness greater than 0.

The effect of vermicompost on growth of shallots (Allium ascalonicum L.)

Shallots have long been cultivated by farmers intensively because shallots have a high economic value, so they become a source of income for farmers. Shallots are annual plants belonging to monocotyledonous plants that have multi-layered tubers formed from layers of leaves that enlarge and unite with cylindrical leaves. The soil fertility level influences shallots' growth, development, and production, requiring additional fertilizers. One of the good fertilizers used is vermicompost. Vermicompost is an organic fertilizer containing microbes and elements required for plant growth. This study aims to determine vermicompost's effect on shallot growth (Allium ascalonicum L.). This study used a completely randomized design with ten replications. The treatment levels consisted of P0 = 0 grams of vermicompost per 1 kg of soil, P1 = 40 grams of vermicompost per 1 kg, P2 = 80 grams of vermicompost per 1 kg of soil, and P3 = 120 grams of vermicompost per 1 kg of soil. Parameters observed were the number of leaves, number of tubers, plant height, wet weight, dry weight, and chlorophyll content of shallot. The research data were analyzed using ANOVA and Duncan's Multiple Range Test at the 5% level. The results showed that the addition of vermicompost had a significant effect on the number of leaves and chlorophyll content of the shallot but had no significant impact on the number of bulbs, plant height, wet weight, and dry weight of the shallot.

Distribution Characteristics and Influencing Factors of Soil Biological Indicators in Typical Farmland Soils

Soil biodiversity drives soil-based ecosystem services and is an important indicator of soil health. To understand the responses of important soil biological indicators to different farmland use contexts, 72 fields in three agricultural regions of China were used as research objects. The distribution characteristics and the factors influencing six indicators (carbon and nitrogen contents of soil microbial biomass (MBC, MBN, respectively), soil respiration (SR), soil catalase activity (CAT), soil acid phosphomonoesterase activity (APA), and soil earthworms) were investigated using field monitoring and indoor analysis. The MBC, SR, CAT, and APA indicators showed significant differences among the regions (p < 0.05). Correlation and redundancy analyses indicated that the important factors affecting MBC, MBN, and soil respiration were cation exchange capacity, total N, organic matter, hydrolytic N, and soil bulk density, whereas the important factors affecting APA and earthworms were total phosphorus, available phosphorus, and available potassium. None of these factors had a significant effect on CAT. Climatic conditions, soil types, and farmland practices all have complex impacts on soil biodiversity. The results showed that attention should be paid to improving the physical conditions of the soil and to increasing soil fertility levels when establishing sustainable farm management patterns.

IMPROVEMENT OF EX-GOLD MINING SOIL THROUGH THE APPLICATION OF RUBBER LEAF LITTER COMPOST AND BIOCHAR OF OIL PALM EMPTY FRUIT BUNCHES ON THE GROWTH OF RUBBER SEEDLINGS (Hevea brasiliensis Muell. Arg.) PB-260 CLONE

Land damage caused by gold mining activities is mainly due to soil contamination by Mercury (Hg). Ex-gold mines are soils that have poor chemical, biological, and physical properties, resulting in a very low level of soil fertility. The objective of this study was to determine the effect of rubber leaf litter compost and biochar of oil palm empty fruit bunches to obtain the best dose recommendation in improving the ex-gold mining soil on the growth of rubber seedlings (Hevea brasiliensis Muell. Arg.). This study was designed by a completely randomized design consisted of 7 treatments and repeated 3 times. The treatments were rubber leaf litter compost at a dose of 10 tons/ha and 20 tons/ha, biochar of oil palm empty fruit bunches at a dose of 10 tons/ha and 20 tons/ha, combination of rubber leaf litter compost and biochar of oil palm empty fruit bunches at a dose of 10 tons/ha and 20 tons/ha, respectively. The results showed that the combination treatment of rubber leaf litter compost and biochar of oil palm empty fruit bunches at a dose of 20 tons/ha resulted in a soil pH value of 4,85, Al-dd 0,42 cmol/kg, C-organik 0,92%, N-total 0,053%, C/N 11,25, P-available 122,69 ppm, K-dd 0,40 cmol/kg, and reducing soil mercury by 0,01 ppm. The growth of shoot height and leaves number of rubber seedlings was obtained by the application of biochar of oil palm empty fruit bunches at a best dose of 20 tons/ha. In addition, the treatment of rubber leaf litter compost at a dose of 20 tons/ha was able to increase the leaf width of rubber seedlings (h. brasiliensis Muell. Arg.).

Biological reclamation of disturbed agricultural lands in the Volgograd Trans-Volga region

Earthworks, such as mining, construction, laying pipes for various purposes and other activities, result in the loss of ecological systems, particularly soil cover integrity. Land reclamation allows for the establishment of a fertile soil layer, soil structure, and the accumulation of humus and other nutrients up to the level of fertility that existed before the violation. The article presents a comparative analysis of the main indicators of soil fertility of agricultural lands (pasture, hayfield, arable land) in its natural state and in the disturbed one caused by the overhaul of the main gas pipeline. The purpose of the research conducted in 2020 was in the dry-steppe zone of chestnut soils of the Volgograd region to analyze the indicators of fertility of agricultural lands that are in their natural state and subject to reclamation with an estimation of restoration costs. To characterize the level of soil fertility, the main indicators of fertility have been considered: particle size distribution, content of organic matter (humus), nitrogen (N), phosphorus (P), potassium (K), sulfur (S) and pH, which reliably characterized soil fertility in the given soil-climatic conditions of the dry steppe zone of the Volgograd region. As a result of the estimation, it was found that the cost of restoring 1 ha of arable land made 2607.13 euro, and the cost of restoring 1 ha of pasture (haymaking) reached 2096.62 euro.

Effect of soil fertility level on growth of cover crop mixtures and residual fertilizing value for spring barley

The use of cover crops may play an important role in ecological intensification of farming systems through their impacts on cycling and the availability of essential nutrients. However, little is known about the effect of soil fertility on the performance of cover crops and consequent nutrient dynamics. We performed a two-year field trial to quantify the effect of two soil fertility levels (low and moderate) on the growth and nutrient content of different leguminous and non-leguminous cover crop species and their mixtures, and on their fertilizing value for the succeeding crop.Overall, the growth and shoot nutrient content of cover crops in autumn was influenced by the species, mixture choices and soil fertility level. The growth of some species was less affected by fertility level than others. Among the legumes, fertility levels had no effect on the growth of lupin. Among the non-legumes, buckwheat had the highest biomass production as well as C:N ratio at a low fertility level, and in the first year was affected least by soil fertility level. However, buckwheat and lupin grown as a single species or in mixtures did not lead to yield improvements in the subsequent crop. Generally, legumes produced more biomass than non-legumes in the mixtures at the low fertility level, whereas non-legumes produced more biomass at the moderate fertility level. Growing a mixture of vetch and radish achieved the best synergetic effect and highest shoot N content. In both years, the greatest improvements in barley yields were achieved after vetch grown as a single species and in a mixture with radish (by up to 46 %). Rye was less competitive in mixtures than radish and buckwheat, and in the second year it had a negative effect on barley yield at the low soil fertility level, presumably due to pre-emptive competition for nitrogen. Soil fertility level had a greater effect on barley yields than cover crop treatments, as yield increments at the moderate fertility level amounted to 48 % in the first year and 64 % in the second year compared with the low fertility level.These results demonstrate that the cultivation of winter-persistent legumes alone or in a mixture with oilseed radish offers a promising tool for improving the yields of subsequent crops through nitrogen input and nutrient cycling on farms where soil fertility level is low.

Physical-Chemical Characteristics of Three Soils and Their Effects on the Growth and Nutritional Status of Coffee Trees

Aims: The conversion of fallow land for the establishment of new orchards is now an alternative to Ivorian coffee growing, which has long been based on the extensive and shifting cultivation system favoured in the past by the abundance of forest reserves.
 Study Design: Thus, three fallow soils under coffee trees were studied from a physical-chemical point of view in order to determine their potential for the productivity of new coffee varieties (Coffea canephora Pierre, var. Robusta).
 Place and Duration of Study: The study was conducted on the National Centre of Agriculture Research (CNRA) research station at Abengourou, Divo and Man for six months, between June and November.
 Methodology: Soil samples and coffee leaves were collected and analyzed in the laboratory according to standard methods to determine their chemical status. Plant growth (height, crown diameter, number of orthotropic, number and length of plagiotropic internodes) was studied in relation to the physical-chemical characteristics of the soil.
 Results: The chemical potential of the soils was found to be low overall. Soil deficiency was characterized by low base saturation (less than 30%), organic matter, nitrogen and cation imbalance, as regard as potassium (K), calcium (Ca) and magnesium (Mg). Growth parameters of the coffee trees and their nutritional status were correlated with the physicochemical properties of the soil.
 Conclusion: In view of these results, sustainable coffee production requires an improvement in the level of soil fertility under coffee trees.

Justification of the approach to establishing levels of soil fertility (on the example of a farm)

The information of agrochemical monitoring of elementary sections of fields allows us to study soil fertility in more detail. For example, using cluster and discriminant analysis methods to identify different levels of agricultural soil fertility. At the same time, it is necessary to comply with the criteria of grouping by fertility. 1. Low spatial contrast of agrochemical properties. If it is present (checked by indicators of asymmetry and kurtosis), then it must be weakened - to bring the data values in the sample to a normal distribution or close to it. Otherwise, information on some indicators may be veiled by extremely high values of others. 2. Reliable participation of all registered soil indicators in the allocation of several groups of sites with similar characteristics (cluster analysis). 3. Equivalent (according to Lambda-Wilkes) and reliable contribution (in terms of significance) of indicators in the allocation of fertility levels. At the same time, it is possible to determine the proportion of sites with different classes of availability of batteries or degrees of acidity. The research was carried out on the basis of data from agrochemical monitoring of soil indicators of leached chernozem of heavy loamy granulometric composition in JSC "General Skobelev", Ryazan region. Salt acidity, mobile forms of phosphorus and potassium, humus were determined by publicly available methods. Two fertility options have been established - conditionally level No. 1 and No.2. According to level 2, the acidity of leached chernozem is shifted to a greater extent to a slightly acidic region compared to level No. 1. The ranges of values for mobile phosphorus correspond to the average - 72-92 mg/kg (level No. 1) and elevated - 103-122 mg/kg (level No. 2) security classes, for mobile potassium - an elevated class. However, for level No. 2, the values were higher (145-167 mg/kg) compared to level No. 1 (114-138 mg/kg). A similar nature of differences was observed in humus. We believe that the information on the fertility of leached chernozem, characteristic of level No. 1, can serve as a guide for the soil of elementary areas with the worst characteristics.

Analysis of physical and chemical characteristics of soil in coffee plantations in the Mount Puntang Social Forestry Area, West Java

Characteristics of soil physics, chemistry, and altitude are important aspects to assess the quality and level of soil fertility. Field studies and laboratory analysis have been carried out to determine some of the physical and chemical characteristics of the soil at an altitude of 1200 m 1300 m 1500 m above sea level. The research aims to analyze the physical and chemical properties of the soil at various altitudes in the coffee plantation social forestry area. The research was conducted in the highlands of Mount Puntang, West Java Province, using survey methods, field observations, and laboratory analysis. Soil samples were taken randomly and then analyzed for soil water content, texture, pH, C-Organic, Nitrogen, C/N ratio, P2O5, and K2O at the Cimanggu Soil Research Institute Laboratory, Bogor. The results showed that the highest available soil water was found at an altitude of 1300 m asl, namely, 15.83% at a depth of 30 cm, with a dusty loam texture. While pH (4.50 - 6.00), C-organic (1.99 - 4.32 %), N-total, (0.18 - 0.32 %) C/N-ratio (11 - 14 % ), P2O5 (8 -13 ppm) and K2O (461 – 579 ppm).
 
 Keywords: coffee plantation, physical properties, chemical properties, arabica Puntang, Puntang mountain

Diversity of soil fertility management options in maize-based farming systems in northern Benin: A quantitative survey

Introduction: Maize-based production systems in Sub-Saharan Africa are largely based on family farming, which is characterized by low-input, nutrient-mining agriculture and practices. These systems usually promote soil degradation through loss of organic matter and erosion. The present study characterizes farms and main soil fertility management options in maize-based farming systems of the northern Benin.Methods: The study was conducted in the municipalities of Malanville, Banikoara and Bembèrèkè. We sampled randomly and interviewed 262 maize farmers, and the statistical analysis (distribution of means and frequencies, chi-square, ANOVA, etc.) was performed.Results and discussion: The results show that maize farming characteristics and socioeconomic conditions (land use and labor, production activities and land allocation, institutional arrangements on land, access to labor and capital, etc.) were diverse across locations and exhibited a wide variation within locations. Several practices were used for the management and sustainable maintenance of soil fertility in maize production systems in northern Benin: maize-legume intercropping, cotton-maize rotation, and mineral and organic fertilizers application. Most of farmers occasionally or regularly used mineral fertilizers (95.4%), followed by legume-cereal rotation/ intercropping (51.9%). Overall, 23.6% and 58.4% of farmers consistently used mineral fertilizer over the last 5 and 10 years, respectively. The amount of applied mineral fertilizer did not significantly vary between locations with an average (applied day after sowing, DAS) of 131.7 ± 13.7 (22 ± 8 DAS), 58.7 ± 9.6 (44 ± 5 DAS) and 164.7 ± 25.4 (38 ± 11 DAS) kg ha−1 for NPK, urea and Mix NPK + urea, respectively applied at, and days after sowing. Most farmers spread the fertilizer around the plants without covering with soil particles. Manure was applied exclusively to food crops through transporting and corralling (28.2%); and most farmers also used manure from their own livestock while few farmers used cattle corralling. Farmyard manure was mainly spread (100% of respondents) on the surface before plowing at the beginning of the rainy season. Maize farmers applied mineral fertilizer based on the level of initial soil fertility (naturally fertile or poor, degree of erosion etc.) and fertilizer purchase costs. Manure was not widely used as an alternative to chemical fertilizers; therefore, farmers need more strengthening and technical assistance on the production of organic fertilizers and manure storage. The findings are useful for policymakers on encouraging the successful implementation of sustainable soil fertility management strategies of maize-based farming systems in northern Benin.

Physico-chemical and agrochemical indicators of typical chernozem and isohumisol under various tillage and fertiliser systems

The relevance of examining the physico-chemical and agrochemical indicators of soils lies in the fact that these properties determine the level and quality of agricultural crops, thus affecting the food security of the country as a whole. In this regard, the purpose of the study is to establish the longterm impact of different soil tillage and fertilisation technologies on the profile distribution of physicochemical and agrochemical indicators of typical chernozem and isohumisol soils. Under conventional tillage (CTu), plant nutrients were evenly distributed within the upper layer of typical chernozem, with the highest values observed in the 10-40 cm depth range. Under soil conservation tillage, with the addition of straw at a rate of 1.2 t/ha+N12+N78P68K68, the content of available hydrolyzable nitrogen, mobile phosphorus, and exchangeable potassium in the typical chernozem soil was highest in the 0-20 cm layer: 192.30±22.44 and 192.51±22 mg/kg; 63.57±5.762 and 62.07±0.312 mg/kg; 527.14±36.204 and 465.27±5.844 mg/kg for shallow (RTu) and deep (DRTu) soil conservation tillage, respectively. In total at 0-100 cm layer of typical chernozem, the highest content of plant nutrients was observed under DRTu followed by CTu. In Chinese isohumisol, a higher accumulation of NH4 + -N and NO3 -N was observed in the 0-10 cm depth range under no-till soil management, while in the 20-40 cm depth range, plowing resulted in greater accumulation of these nutrients. The total phosphorus content did not notably change with depth. Under the application of fertilisers, the content of nutrients and the reaction value of the medium increased for all tillage treatments of typical chernozem. The content of exchangeable calcium and magnesium did not change considerably on the fertilised inputs. The findings of this study indicate the feasibility of using crop residues with nitrogen compensation and cover crops, in conjunction with mineral fertilizers, to maintain the fertility level of chernozem soils under conditions of limited manure utilisation

Determinants of perception of climate change and adaptation strategies of coffee-based agroforestry farmers in western Ethiopia

Background: A range of local social and environmental factors has an impact on farmers' views of climate change and choices on the use of coping mechanisms. This study examines the factors that are limiting farmers' perceptions of climate change and their coping mechanisms in Gimbi district, Western Ethiopia. Methods: A household survey and focus group discussion were employed to collect relevant data. A total of 402 randomly selected households and six focus group discussions containing 72 participants were used to gather data. Binary logit models were used to analyze the collected data. Results: Farmers noted that some of the signs of climate change included increasing temperature, erratic rainfall, late onset of rainfall, and early cessation of rainfall. We discovered that there are three distinct sets of climate adaption strategies used by farmers: crop management, soil and water conservation and intensive farm management. The primary determinants of farmers' perceptions of climate change and adaptation techniques were household head age, education, soil fertility, market access, and agricultural training. Age, education, and soil fertility level were the characteristics that significantly impacted farmers' perspectives and coping mechanisms among the primary drivers evaluated in the area. Use of agroforestry, shifting planting dates, and fertilizer application were all essential farming practices used as climate adaptation measures. Conclusions: Both socioeconomic and environmental factors have found to affect farmers' perceptions of climate change in the area. The existing socioeconomic and environmental factors, in turn, affect their choice of strategies to adapt to climate change. When implementing climate change adaption strategies, it is critical to assess farmers' level of awareness of climate change and their coping strategies, as well as the factors limiting their ability to adapt to climate change.

Determinants of perception of climate change and adaptation strategies of coffee-based agroforestry farmers in western Ethiopia

Background: A range of local social and environmental factors has an impact on farmers' views of climate change and choices on the use of coping mechanisms. This study examines the factors that are limiting farmers' perceptions of climate change and their coping mechanisms in Gimbi district, Western Ethiopia. Methods: A household survey and focus group discussion were employed to collect relevant data. A total of 402 randomly selected households and six focus group discussions containing 72 participants were used to gather data. Binary logit models were used to analyze the collected data. Results: Farmers noted that some of the signs of climate change included increasing temperature, erratic rainfall, late onset of rainfall, and early cessation of rainfall. We discovered that there are three distinct sets of climate adaption strategies used by farmers: crop management, soil and water conservation and intensive farm management. The primary determinants of farmers' perceptions of climate change and adaptation techniques were household head age, education, soil fertility, market access, and agricultural training. Age, education, and soil fertility level were the characteristics that significantly impacted farmers' perspectives and coping mechanisms among the primary drivers evaluated in the area. Use of Agroforestry, shifting planting dates, and fertilizer application were all essential farming practices used as climate adaptation measures. Conclusions: Both socioeconomic and environmental factors have found to affect farmers’ perceptions of climate change in the area. The existing socioeconomic and environmental factors, in turn, affect their choice of strategies to adapt to climate change. When implementing climate change adaption strategies, it is critical to assess farmers' level of awareness of climate change and their coping strategies, as well as the factors limiting their ability to adapt to climate change.

Increasing the Payback of Nitrogen Fertilizing of Winter Wheat with the Use of Original Methods for Calculating Their Optimal Doses

In the central zone of the Krasnodar Territory of the Russian Federation, on the pre-Caucasian low-leached heavy-duty chernozem on the basis of the P.P. Lukyanenko National Grain Center, for more than 15 years, new, more effective methods for calculating optimal doses of nitrogen fertilizing of winter wheat, characterized by high payback, have been studied. The methodological basis of the study was the assumption that when calculating optimal doses of nitrogen fertilizers, it is necessary to take into account the initial level of effective soil fertility, the state of agrophytocenosis and the planned yield. The solution of this problem is possible only with the help of a systematic analysis of the relationship of winter wheat yield with the above factors, the construction of a regression multiple nonlinear mathematical model and mathematical modeling of various situations in the search for optimal doses of top dressing. As initial information, the data obtained in long-term multifactorial field experiments were used, which resulted in the development of 2 new methods for determining the optimal doses of nitrogen fertilizing of winter crops (first and second) that meet the above requirements. The results of 3-year field experiments to study the effectiveness and payback of nitrogen fertilizing of winter wheat, depending on the methods of their calculation, are presented. The agro-climatic conditions at the time of the research, although they were different, but in general turned out to be relatively favorable for obtaining a good harvest of winter wheat. In 2015 and 2016, comparative tests of the effectiveness and payback of 2 new methods for calculating the optimal doses of the 1st and 2nd nitrogen fertilizing of winter wheat were carried out. For comparison, 2 well-known, widely used in practice, tabular methods were selected (prototypes 1 and 2). In 2015, the study was carried out with the Grom variety (predecessor - corn for grain), in 2016 - with the Yuca variety (predecessor - winter wheat). It is shown that the use of original methods for calculating optimal doses of 1st and 2nd nitrogen fertilizing of winter wheat significantly increased their efficiency and payback (both 1st and 2nd in total) compared with the prototypes (by 35-200%), at the same time, the payback of nitrogen top dressing, the doses of which were calculated from the prototypes, was ~12- 14 kg/kg (on average for 2 years), and the payback of top dressing calculated according to the original methods was 22-24 kg/kg in 2021 (forerunner - soy, Adel and Bagrat varieties) studied the effectiveness and payback of nitrogen fertilizing when calculating their doses only by original methods. It was shown that even with a high level of yield of winter wheat in the control (~60 c/ha on average for both varieties), the use of 2 nitrogen fertilizing, the doses of which are calculated according to the original methods, allowed to achieve a yield of winter wheat of 80-90 c/ha with a payback of ~22 kg grains/kg of N fertilizers.

Неоднорідність умісту сполук азоту в деяких орних ґрунтах Лівобережного Лісостепу України

Goal. To research the features of the spatial distribution of the content of nitrogen compounds (nitrate and ammonium groups) in arable soils of different genesis of the Left Bank Forest Steppe of Ukraine and to substantiate the implementation of precision farming measures. Methods. Informational and bibliographic — for summarizing literary data and substantiating the need for conducting research; field — for breaking down a regular grid and taking soil samples; laboratory — to determine the content of nitrogen compounds; statistical and geostatistical — for mathematical processing of data and assessment of the reliability of the obtained data. Results. Based on the analysis of literary sources, the role of nitrogen compounds in plant nutrition was outlined, the heterogeneity of the content of agrochemical properties of arable soils, including the content of ammonium and nitrate forms of nitrogen, was analyzed. It was confirmed the existence of heterogeneous distribution of nitrogen compounds content in the spatio-temporal continuum during the observation period. It was established that the nitrate form of nitrogen has a quantitative advantage in the soils of the Left Bank Forest Steppe of Ukraine, which differ in species composition, compared to the ammonium form. The important role of the granulometric composition of soils in the spatial distribution of the content of nitrogen compounds was noted. It was established that nitrate nitrogen compounds are more dynamic compared to ammonium compounds, which makes it possible to carry out diagnostics and recommend the implementation of precision farming measures based on the content of nitrate nitrogen. Conclusions. Changes in the spatial structure of the distribution of ammonium and nitrate forms of nitrogen at both production objects were recorded during the observation period. It has been proven that the supply of soil with nitrogen is determined by the presence of heterogeneous landforms and, to a lesser extent, by the genetic composition of soils. It was established that nitrogen nitrate compounds are more unstable in space and time during the observation period compared to ammonium compounds. On the basis of geostatistical data processing, the existence of heterogeneity in the content of nitrogen compounds in the studied soils was confirmed. It was established that nitrate compounds are more unstable in space and time during the observation period compared to ammonium compounds, which makes it possible to recommend the implementation of precision agriculture measures, in particular, differentiated application of nitrogen fertilizers, precisely on the basis of diagnostics of nitrate nitrogen content in soils. Over time, this will allow to equalize the level of soil fertility for the nutrition of agricultural crops in order to obtain stable yield.

Artificial reseeding improves multiple ecosystem functions in an alpine sandy meadow of the eastern Tibetan Plateau

AbstractDesertification in alpine grasslands is exacerbated by rapid climate change and intensive anthropogenic activity, which will substantially threaten the structure and function of alpine grassland ecosystems. Artificial reseeding was a widely used strategy for the restoration of alpine sandy grasslands. However, it is still unclear whether reseeding restoration can improve multiple ecosystem functions of sandy meadows. To narrow these knowledge gaps, we evaluated the changes in plant communities, soil conditions, and ecosystem multifunctionality (EMF) across native meadow, sandy meadow, and restored meadow on the eastern Tibetan Plateau, and further identified the links between individual and multiple ecosystem functions. Artificial reseeding had contributed to the promotion of plant diversity, productivity, soil fertility, and soil carbon and nitrogen sequestrations. However, the recovery levels of plant diversity, productivity, and soil fertility in the restored meadow were still far lower than that in the native meadow. The results revealed that the EMF index of the restored meadow increased greatly compared with the sandy meadow, but it did not recover to that of the native meadow level. In addition, short‐term reseeding improved the aboveground EMF index more than the belowground EMF index. The EMF indexes and most individual ecosystem functions showed positive correlations with plant diversity and productivity. These findings indicated an important role of artificial reseeding in the restoration of ecosystem functions in the alpine sandy meadow, and it had critical implications for the regional ecological security and sustainable development of alpine grasslands.

ИЗМЕНЕНИЕ УРОЖАЙНОСТИ ЗЕРНОВЫХ КУЛЬТУР ПРИ ДИФФЕРЕНЦИРОВАННОМ ВНЕСЕНИИ МИНЕРАЛЬНЫХ УДОБРЕНИЙ

The increasing of the productivity of agricultural plants is possible under certain conditions, such as maintaining and increasing the fertility of cultivated fields. The research revealed that it is impossible to save and maintain a significant level of soil fertility through the use of organic fertilizers and/or mechanical tillage without the use of fertilizers. A quantitative decrease in their use inevitably occurs with the annual change in the cost of mineral fertilizers, as a result of which the nutrients taken out with the crop harvest are not restored. It leads to sharp reduction in the level of soil fertility and a decrease in crop yields. In order to maintain the balance of the soil in terms of nutrient content in the conditions of biologization of agriculture, increase their fertility and increase productivity, it is necessary to apply acceptable types of affordable and economically justified mineral fertilizers, including their differentiated application.