Soil Reserves Research Articles

Unlocking Potential: The Role of Zinc Fortification Combating Hidden Hunger and Enhancing Nutritional Security

Micronutrient shortage is rapidly becoming apparent have drawn more attention in the cultivation of crops. The main causes of this deficit are the introduction of high-yielding varieties, an intensified cropping strategy, and advanced irrigation systems etc. A further aspect contributing to this issue is the increased use of high analysis chemical fertilizers instead of organic plant nutrition (composts, farmyard manure, etc.). Most countries have acute shortages of micronutrients due to the significant depletion of soil reserves caused by current agricultural production technologies. In order to increase both the quantity and quality of crops, micronutrients are crucial. Through the integration of agronomic, breeding and transgenic techniques, researchers seek to strengthen the zinc concentration in field crops, so improving their nutritional value and mitigating the risk of zinc deficiency in human diets. The availability and absorption of micronutrients in crops are improved by agronomic techniques such as foliar spraying, and soil fertilizer treatment including organic amendments. Meanwhile, biofortification of vegetable and fruit crops has also been achieved by transgenic and breeding strategies. In other hand, Rhizobacteria-based biofortification, Chelated Zn biofortification, nutri-priming are also important techniques in Zinc fortification programs to ensure food security and nutritional quality, bio-fortification of micronutrients in crops is vital. In addition, bio-fortification improved quality and crop output, reducing hidden hunger and demonstrating that it was a viable and economical approach. The present review addresses several aspects of zinc insufficiency in human populations, including public health and socioeconomic issues, bio-fortification and ferti-fortification studies, and future efforts to mitigate zinc deficiency in soil and the population at large.

Towards a national model of humus (carbon) budget management in soils of agroecosystems in the Russian Federation

The prospect of adapting two methods for monitoring the fertility of agricultural soils (humus balance, HB) under spring and winter wheat crops (hereinafter referred to as grain crops) developed in the Russian Federation (RF) for the purposes of climate projects has been studied. It was revealed that the RosNIIzemproekt method (1998) underestimates the HB average value to -7.7 c/ha for RF. The RosNIIzemproekt method (1998) has logical errors in the calculation model and is not recommended for use. The TsINAO method (2000) has a more logical calculation model. According to this method, the average value of HB in soils for RF is generally positive and amounts to 3.3 c/ha (0.71 tCO2-eq/ha carbon units). This value constitutes ≈0.3% of average humus reserves in arable soils of the RF (108 tС/ha). The annual value of change in humus content under spring and winter wheat is incommensurably less than the total humus reserves in the soil. Statistically reliable assessment of changes in humus content requires a huge number of soil samples. This makes the verification procedure economically inexpedient. Another option is proposed to increase the time of humus accumulation. It is considered (IPCC, 2003) that a 20-year accumulation period is sufficient, which corresponds to the duration of soil climate projects. A coefficient (0.216) has been proposed for converting humus reserves (c/ha) to the value of a carbon unit (tCO2-eq/ha). The total sequestration of carbon by soils under grain crops in 2022 was about 11 million 914 thousand tCO2-eq. HB accounting significantly compensates for calculated emissions from agricultural production and reduces them by almost 10% (from 116 to 105 million tons CO2-eq in 2022). For both models of fertility monitoring, an assessment was made of the quality of the regression dependence of HB on the total biomass of photosynthesis (TBP) in soils under grain crops. It is shown that according to Fisher's t-test at a 5% significance level, the studied relationship is significant and characterized by the squares of the correlation coefficient (R2) equal to 0.554 and 0.998. In accordance with the Chaddock scale, the closeness of the correlative relationship between HB and TPB for winter wheat is assessed as high, and for spring wheat as very high.

Carbon Accumulation in Peat Soils of Floodplain Mires of the North-East of the Middle-Russian Upland

The study of the structure of peat deposits of the Bolsheberezovskoye and Podkosmovo inundated mires which were formed during the Atlantic – subboreal periods of the Holocene in the valley of the Nepryadva River, in the north-eastern part of the Middle-Russian Upland. The results of the botanical composition of peat deposits showed that the genesis of mires is represented by eutrophic paleocenoses, which accumulated carbon at a rate of 21.8-95 g/m2 per year. The formed eutrophic peat was characterized by a high degree of decomposition (45-55%) and a low rate of vertical growth (on average, 0.3-0.6 mm/year), which is due to the seasonal dynamics of the level of occurrence of mire waters. The carbon content in peat by peat deposit profiles is 14% for the Podkosmovo mire and 31% for the Bolsheberezovskoye mire. The differences are due to the peculiarities of the water-mineral nutrition of the mires, which is manifested in the high content of carbonates and ash content of the Podkosmovo mire. Carbon reserves in peat soils of inundated mires vary from 51.5 up to 125 kg/m2 for horizons with a capacity of 10 cm. This indicator is determined by the intensity of decomposition of plant residues, which depends on the composition and structure of microbial complexes. On the Bolsheberezovskoye mire the microbial complex is dominated by the fungal component, on the Podkosmovo mire – by the bacterial component. This is the reason for the differences in the microbial biomass of the mires: 222 g/ m2 for the Podkosmovo, 898 g/m2 for the Bolsheberezovskoye mire. The reason for the differences in inundated mires is the range of variation in the level of mire waters during the growing season, due to the reclamation measures carried out in the Bolsheberezovskoye mire. Nevertheless, inundated mires are important “depots” of atmospheric carbon and the intensity of its accumulation is determined by a complex of factors.

Circularity of potassium in a grassland-based dairy farm on a clay loam soil

A proportion of potassium (K) exits grassland-based dairy farms in tradeable products. Potassium imports are typically needed to offset depletion of soil reserves. The objectives of this study were to (i) quantify K entering and exiting a grassland-based dairy farm including K lost to water, (ii) to relate the balance between K entering and existing the farm to soil K fertility status in order to (iii) design a better K fertilisation strategy for grassland under temperate climatic conditions. The quantities of K entering and exiting a grassland-based dairy farm (Solohead Research Farm; 52⁰51’N, 08⁰21’W) were determined each year between 2005 and 2022. Potassium losses to groundwater were measured during the winters of 2020/21, 2021/22 and 2022/23. Averaged over 18 years, K entering (kg ha−1 ± standard error) was 82 ± 11 and exiting was 41 ± 4. The annual average farm K balance was 41 ± 12 kg ha−1 and ranged between −36 and 136 kg ha−1. Annual K loss to groundwater (mean ± SE kg ha−1) ranged between 6.9 ± 6.13 and 59 ± 7.4. Annual average soil test K (STK; following extraction using Morgan's solution (Na acetate + acetic acid, pH 4.8)) concentrations in paddocks across the farm ranged from 85 to 253 mg L−1. The yearly change in average STK concentrations correlated with annual farm K balance in the preceding year (R2=0.59; P<0.001). Annual farm-scale K budgets were useful in quantifying K flows in products and losses. Potassium leaching to groundwater represented the majority (55 %) of K exiting the farm; exceeding export of K in milk and other products. Maintaining overall farm STK status required annual fertiliser K inputs of 22.5 kg ha−1 between 2016 and 2022. This study elucidates the challenges in managing soil K fertility on grassland based dairy farms.

Sustainable extraction and conservation of soil resources: New insights through Natural Gamma-ray Spectrometry based Proximal Sensing Method

Soil is one the most extracted natural raw materials. The vast expanses of fertile alluvial soils of the Indo Gangetic Plains have long remained as abundant soil resource pool for brick manufacturing and construction sectors. Unmonitored continuous removal of soil is reported to cause depletion of soil reserves, loss of soil fertility and affect crop yield. Excavation and removal of soil from isolated patches of land creates low lying and elevated degraded areas which disrupts normal crop cultivation pattern. Natural gamma-ray spectrometry (NGS) can be used as a non-destructive and rapid geophysical sensing method, for identification and delineation of areas with suitable soils. During this work brick kiln areas were visited to understand soil's availability and extraction pattern. NGS measurements of samples from soil profiles were carried out to find if gamma-ray intensities varied with soil clay content. Soil texture and plasticity of the same samples were obtained following standard testing procedures. Winkler and Plasticity charts were used to assess suitability of the soils. A strong linear relationship between gamma-ray potassium (K) intensity and clay contents of soil profile samples (R2 = 0.88) was observed. NGS based devices can be used to scan soil samples rapidly and log shallow depth boreholes in grid sampling design. The gathered spectral gamma-ray data can be then used to predict and generate high resolution 3D models of soil properties, based on which resource areas of suitable soils can be delineated for long term soil extraction without affecting cultivated areas. This will help in delineating areas restricted for soil extraction, which will not only make soil mining sustainable but also address soil conservation by setting aside large cultivated fertile soil areas untouched. Adopting NGS methods will prevent unsystematic removal of fertile soil and creation of degraded lands. This will ultimately result in efficient soil resource management.

Effect of removing the spring flush and nitrogen and phosphorus fertilization on the late ripening of cactus pear Opuntia ficus-indica (L.) Mill

The present work aims to study the effect of removing the spring flush (scozzolatura practice) and nitrogen and phosphorus fertilization on fruit yield and quality of the late fruiting of cactus pear Opuntia ficus-indica (L.) Mill. To meet this objective, an experiment was carried out on an adult plantation of ‘Aissa’ cv in the Agadir area. Treatments of fertilization used are: T0 (not fertilized plot: contains only the soil reserve in NP: 40-20 kg N-P ha-1), T1: 226 kg N ha-1, T2: 114 kg P2O5 ha-1 and T3: 226-114 kg N-P2O5 ha-1. The whole spring flush was removed during the full flowering stage (50% flowers in bloom); it was practiced on April 20, 2019. Obtained results showed that removing the spring flush led to a second flush of flowering (reflowering) 46 days after the spring flowering and an off-season late fruiting 68 days after the seasonal fruiting. The scozzolatura practice also has improved the fruit size and taste and its content in sugars, and reduced the number of seeds per fruit. Nitrogenous and phosphor-nitrogenous fertilizations improved the emission of shoots and flowers, fruit yield and size of scozzolatured and not scozzolaturated plants and their effect is more important on scozzolatured plants than on not scoscozzolatured ones. However, phosphorous fertilization alone does not affect these phenological and yield parameters and nitrogen and phosphorus fertilizations have no effect on the organoleptic parameters of the fruits (the rate of juice and sugars and the pH and acidity titratable of the juice).

Effect of increasing rate of P fertilization on available P content in soil and plant uptake: implications for P management

The application of phosphorus (P) is necessary for sustainable crop production. Its application rate is often based on soil analysis. However, the P availability is not always properly evaluated for optimal P management. The effect of long-term P fertilization on soil P availability, yield, and plant uptake of P was investigated using data from a long-term field experiment. We hypothesized that: 1) an increasing rate of P fertilization increases soil P content, yield, and P uptake, and 2) annual change of P uptake and P content increases from negative to positive values at an increasing rate of P addition. Different strategies of P management were evaluated using experimental results. Increasing inputs of P in mineral or organic form increases soil P content. However, the effect on yield is limited and unused P accumulates in soil. High yield ensuring strategy of P fertilization is therefore not useful as a way of P management. Results suggest that keeping soil P content in the range of 50–80 mg P kg−1 and organic fertilization (and probably also legume cropping) are useful ways of using P from fertilizers or soil reserves. Results also suggest that Mehlich III soil test brings useful information for P management.

ФОРТЕЦІ ЛІВОБЕРЕЖНОЇ УКРАЇНИ ЯК СИРОВИННА БАЗА ДЛЯ СЕЛІТРОВАРІННЯ У 18 СТОЛІТТІ

The article is devoted to the study of the history of saltpeter mining on the territory of the Left Bank of Ukraine and the fate of the earth defense structures of the Cossack fortresses in this process. Nitrate production in the territory of the Left Bank of Ukraine was a fairly widespread industry. The development of artillery and firearms in early modern armies was one of the reasons for the increase in saltpeter production. In the 17th century, mounds of barrows and ramparts of ancient fortifications were used for its extraction, where saltpeter was naturally concentrated. But this method depended on the coincidence of many factors. From the second half of the 17th century on the territory of the Hetman Oblast and the Slobozhan Oblast, the on-board method of saltpeter mining is increasingly spreading. The appearance of saltpeter plants, which worked with artificial edges, greatly simplified the process of saltpeter production, but also required finding places for their location. At this time, saltpeter workers paid attention to the abandoned fortresses built in the 17th century, which had a convenient location and soil reserves for the construction of artificial banks. During the 18th century, the role of fortresses in the defense of Left Bank Ukraine is gradually changing. At the beginning of the century, they were an important component of defense, but over time their influence gradually decreases. Some of them are falling into disrepair, and the rest are turning into rural settlements. The territory of the abandoned fortresses was a convenient location for saltpeter workshops, and the defensive structures served as a raw material base for saltpeter mining. If in the first half of the 18th century the hetman's administration followed the preservation of fortresses, then in the second half of the century this process became widespread even without the restoration of the ramparts. The final destruction of defensive structures by saltpeter’s took place at the end of the century and was connected with the re-planning of cities.

Carbon Stock in Coastal Ecosystems of Tombolos of the White and Baltic Seas

“Blue carbon”, apart from marine humus, includes the carbon (C) stock of coastal ecosystems such as mangroves, saltmarshes, and seagrass meadows, which have been overlooked until recently. Information about the role of coastal wetlands in C sequestration and providing other ecosystem services is still insufficient. In the present study, we assessed the C reserves of soils and vegetation biomass in two complex coastal landscapes (tombolos) located on the coasts of the White and Baltic seas. The soil and plant C stocks were slightly higher at the plot on the Baltic Sea (93.4 ± 46.7 Mg C·ha−1 and 5.22 ± 2.51 Mg C·ha−1, respectively) than at the plot on the White Sea (71.4 ± 38.2 Mg C·ha−1 and 3.95 ± 2.42 Mg C·ha−1, respectively). We attributed the higher values of the C reserved to a warmer climate and less saline water at the plot on the Baltic Sea. Both soil and plant C showed high heterogeneity due to geomorphological complexity and differences in vegetative communities. The Phragmites australis community showed the highest plant biomass and, in some places, high soil C reserves. Allochthonous C contributed to the soil C stock at the site on the White Sea. Though P. australis sequestered more C than other communities, its effect on ecosystem services was mostly negative because the invasion of reeds reduced the biological diversity of the marshes.

Estimation of Carbon Stocks in Soils of Forest Ecosystems as a Basis for Monitoring Climatically Active Substances

The eluvozems and soddy eluvozems on two-layer deposits dominating in the soil cover of the Zvenigorod biostation of Moscow State University contain, on average, 65–83 t/ha of organic carbon in the litter and a meter-deep layer of mineral strata. Carbon stocks are minimal in the soddy eluvozem of the complex spruce forest (59–68 t/ha), which is characterized by a lighter granulometric composition, and reach 76–92 t/ha in the soils of the birch–spruce and complex pine–spruce forests. At the same time, 3.3–5.8 t C/ha or 4–9% of the total organic carbon reserves are concentrated in the litter, and 64–69% in the upper mineral layer (0–20 cm). Different levels and profile distribution of organic carbon reserves in soils are determined by lithological and granulometric features and the nature of vegetation. The contribution of water-extractable organic carbon compounds to their total content in the upper mineral horizons of soils does not exceed 1.3–1.8%, microbial carbon, 1.7–2.4%. In acidic light loamy soils, the enrichment in calcium and potassium, the cation exchange capacity, the content of exchangeable bases, and the degree of saturation can serve as indicators of the content and reserves of organic carbon at the ecosystem level. The relationship with the content of finely dispersed fractions and oxalate-extractable Al and Fe is manifested to a lesser extent due to the similar origin and properties of soils. The variability of organic carbon stocks in soils is determined to the greatest extent by its content, the influence of which decreases with depth. Accounting for spatial heterogeneity, field measurements of the density and proportion of fine earth, and correct analytical determinations are essential components of the assessment of carbon stocks in soils of forest ecosystems as part of a national monitoring system for carbon pools and greenhouse gas fluxes under development.

Effect of removing the spring flush and phosphor-nitrogenous fertilizing on fruit yield and quality of the late fruiting of cactus pear Opuntia ficus-indica (L.) Mill

The aim of this work was to study the effect of removing the spring flush (scozzolatura practice) and phosphor-nitrogenous fertilizing on fruit yield and quality of the late fruiting of cactus pear Opuntia ficus-indica (L.) Mill. To meet this objective, trials were carried out on an adult plantation of ‘Aissa’ cv in the experimental station of Hassan II Institute of Agronomy and Veterinary Medicine in Agadir. The scozzolatura practice consisted of removing the whole spring flush of flowers and cladodes during full blooming (50% flowers in bloom). The amount of fertilization provided are: 0-0, 120-18 and 195-33 kg N-P2O5 ha-1. The soil of the site of trials contains a reserve of 30-12 kg N-P2O5 ha-1 and the treatments of fertilization studied are: (T0) (control without supply, only the reserve of soil) 30-12 kg N- P2O5 ha-1, (T1) 150-30 kg N-P2O5 ha-1 and (T2) 225-45 kg N-P2O5 ha-1. Obtained results showed that the scozzolatura practice reduced fruit yield, while it improved fruit size. Nitrogen and phosphorus (N-P) fertilizing increased fruit yield and size of scozzolaturated and not scozzolaturated plants with more effect on scozzolaturated plants and T2 treatment yielded more than the other treaments of fertilization. Interaction of the two factors scozzolatura practice and N-P fertilizing does not affect (p ˃ 0.05) fruit yield and size of scozzolaturated plants.

Siltation of check dams alters microbial communities and thus limits organic carbon mineralization

Check dam interception in the Loess Plateau leads to a buildup of silt-based deep soil reserves. These deep soils tend to be high in organic carbon (C), and could dramatically impact our estimates of terrestrial C storage. Despite a growing interest in the terrestrial C cycle, little work has focused on deep soil organic carbon (SOC) pools. In this study, we observed how soil depth and consequential oxygen concentration may influence the way in which microorganisms act on the SOC mineralization process. We found that the change from aerobic to anaerobic environment led to a decrease in cumulative mineralization from 1.37 mg to 1.06 mg and a significant decrease in mineralization rate, which had a limiting effect on SOC mineralization. The reduction of oxygen concentration (approximating depth) also led to changes in the dominant population of bacteria/fungi. Microorganisms with higher C metabolism capacity in aerobic conditions had higher utilization of C sources than that in anaerobic conditions, and vice versa. The limiting factors affecting the amount of SOC mineralization in aerobic soil were carbohydrate, Rokubacteria and Mortierellomycota, and that in anaerobic soil were Amino acid, Mortierellomycota and Ascomycota. Microorganisms with high C metabolism in anaerobic conditions have a weaker metabolism in aerobic conditions, and vice versa. We further quantified the direct and interactive contribution of each factor to SOC mineralization and found that when the soil was aerobic, the contribution of single factor to SOC mineralization was significantly lower (0.32) than the interactions (0.65). Conversely, when the soil was anaerobic, the contribution of single factor to SOC mineralization was much higher (0.76) than the interactions (0.20). When the soil is in anaerobic condition for a long time, the contribution of single factor will gradually increase and the interactions among factors will gradually weaken, further limiting SOC mineralization. In this study, the mechanism of SOC mineralization based on microbial activity in anaerobic and aerobic environment of check dam was reported for the first time, providing theoretical support for understanding the contribution of check dam construction to SOC pool on the Loess Plateau.

Intercalation vs Adsorption Strategies of Myo-Inositol Hexakisphosphate into Zn-Fe Layered Double Hydroxide: A Tiff between Anion Exchange and Coprecipitation.

Myo-inositol hexakisphosphates (IHPs) or phytates are the most abundant organic phosphates having the potential to serve as a phosphorus reserve in soil. Understanding the fate of IHP interaction with soil minerals tends to be crucial for its efficient storage and utilization as a slow-release organic phosphate fertilizer. We have systematically compared the effective intercalation strategy of a phytate onto Zn-Fe layered double hydroxide (LDH) acting as storage/carrier material through coprecipitation and anion exchange. Powder X-ray diffraction, X-ray photoelectron spectroscopy, elemental analysis, thermogravimetric analysis, FTIR spectra, and molecular modeling demonstrated the formation of phytate-intercalated Zn-Fe LDH through coprecipitation with a maximum loading of 41.34% (w/w) in the pH range of ∼9-10 in a vertical alignment through monolayer formation. No intercalation product was obtained from the anion exchange method, which was concluded based on the absence of shifting in the XRD (003) peak. A change in the zeta potential values from positive to negative and subsequent increase in solution pH, with decreasing phytate concentration, are suggestive of adsorption of IHP onto the LDH surface. The batch adsorption data were best fitted with Langmuir isotherm equation and followed the pseudo-second-order kinetic model. The maximum adsorption capacity was found to be 45.87 mg g-1 at a temperature of 25 ± 0.5 °C and pH 5.63.

PLANT COMPOSITION AND SOIL PROPERTIES DURING POSTAGROGENIC EVOLUTION IN THE CIS-BAIKAL FOREST-STEPPE ZONE

Purpose. The purpose of the study was to examine the features of the restoration of plant communities and some properties of gray forest soils, including the humus state, during their post-agrogenic transformation in the conditions of the Cis-Baikal forest-steppe zone.&#x0D; Materials and methods. The study was carried out using the post-agrogenic chronosequences, including arable land, abandoned soils of different ages, and natural cenoses (meadow and forest). Traditional methods of phytocenology were applied to study the plant composition. Mixed soil samples from three trenches were collected from the former arable layer of 0–20 cm. The content of organic carbon (Corg), total nitrogen (N), and the C/N ratio, the pH(H2O) and pH(KCL) values, as well as soil density and the reserves of Corg were determined. The statistical processing of data was performed using One Way ANOVA (Sigma Plot from Windows Version 14.0).&#x0D; Results. It was shown that plant vegetation being typical for the Baikal forest-steppe zone was recovering after the cessation of plowing. At the same time, the several ruderal species were preserved in the plant composition during a long period. This specific phenomenon could be the cause for inhibition of terminal phytocenoses formation. Along with the change in the vegetation, a significant increase in the organic carbon content was revealed in the soils of chronosequences. At the later stages of post-agrogenic succession the carbon reserves in soil were 1.5 times higher than those in arable soil. The humus content in the soils increased with age of the abandoned lands, but no cardinal changes in its qualitative composition were observed. The data indicated the stable functioning of the system of humus substances in the gray forest soils of the Baikal forest-steppe zone during their post-agrogenic evolution.&#x0D; Conclusion. The results can be used for the forecast of post-agrogenic soil changes under various scenarios of land use in conditions of the Baikal region.

Potassium in brown soils of mountain pastures of Uzbekistan

The studied mountain brown soils are characterized by loamy granulometric composition, nutty-cloddy structure, slightly acidic or slightly alkaline reaction. The total potassium content in the upper horizon varies from 1.240 to 1.685 %. Exchangeable potassium ranges from 265 to 1028 mg/kg of soil. The share of clay fraction varies from 2.9 to 18.3 %. In silty fractions, the con- tent of potassium is 2-3 times higher than in the soil as a whole and ranges from 1.26 to 3.02 %. Potassium reserves were identified - near, immediate and potential. Fluctuations in the content of potassium reserves in the humus horizon of the total content were: immediate from 1.5 to 8.31 %, near ө from 5.40 to 32.85 %, potential, dominant in the total content 65.12 to 93.0 %. It has been established that the distribution of potassium and its reserves in the pasture mountain brown soils of Uzbekistan is uneven and depends on many natural factors. It was revealed that potassium of a potential reserve is presented in a sufficiently large amount, and in a slightly smaller amount - near and immediate. Losses of near and immediate reserves of potassium lead to a decrease in the content of total potassium in general.

Effects of Source and Rates of Potassium Fertilizer on Yield Traits and Potassium Use Efficiency of Potato in a Kenyan Ferralsol

Aims: Potassium (K) is one of the nutrient elements taken up in large amounts by potatoes, yet there is little research output on K fertilization of the crop in Kenya, due to the assumption that its natural soil reserves are sufficient for the production of most crops. The study objective was to determine the influence of two K sources (muriate of potash – KCL and sulphate of potash – K2SO4) on K use efficiency and tuber yield components of potatoes in one agro-ecological zone of Kenya.&#x0D; Place and Duration of Study: The experimental site was the University of Eldoret farm in Kenya, located at latitude 0o574942’ N and longitude 35o300772’ E, during the middle - second rains season (S1) and middle rains season (S2) of 2020 and 2021 respectively.&#x0D; Methodology: Treatments were: 0 kg K ha-1 (control), 60,120,180 and 240 kg K ha-1 in S1 and 0, 30, 60, 90, 120 and 180 kg K ha-1 in S2, supplied in the form of KCL and K2SO4. Treatments were laid in a Randomized Complete Block Design in 2x5 and 2x6 factorial arrangements in S1 and S2 respectively. The potato variety planted was Destiny. Data collected included: Agronomic efficiency of K (AEK,), total tuber yield, two categories of seed yield (Size 1 tubers with diameters of 28- 45 mm; Size 2 tubers with 46 - 60mm diameter), total seed yield and ware yield (tubers with diameters over 60mm).&#x0D; Results: During the drier S1, the application of 120 kg K ha-1 in the form of K2SO4 significantly (P &lt; .001) increased the yield of size 1 tubers, total seed yield and total tuber yield. The total tuber yield increment from this K rate was only 12.6 % of the varietal potential yield, and its AEK was 0.042 tonnes of tubers kg-1 K. Therefore its application may not be economically viable. During the moisture-sufficient S2, all K fertilizer treatments in the form of KCl and 90 kg K ha-1 in the form of K2SO4, contributed a yield increase of 58.1 - 68.6% and slightly exceeded varietal yield potential. Additionally, 30 kg K ha-1 of KCL gave the highest AEK of 0.5 tonnes of tubers kg-1 K and consistently enhanced the yield of all potato sizes, except size 1.&#x0D; Conclusion: Under similar ecological conditions as S2, potato farmers can achieve the highest AEK and potential tuber yield with the application of 30 kg K ha-1 of KCL. However, more trials on K nutrition in potatoes need to be done in diverse environments.

Modelling the effects of soil organic content and pH on the yield responses of tea to nitrogen fertilizer

CONTEXTSustained high yields of tea rely on the supply of nitrogen (N) from soil reserves, typically maintained by N fertilisation from inorganic or organic sources. OBJECTIVEThis paper describes how soil N levels, including the effects of soil organic content and pH, were developed and incorporated into a crop yield simulation model called CUPPA-Tea. METHODSThe nitrogen dynamics are presented in terms of i) the initial nitrogen stocks, ii) the addition of nitrogen to the system, iii) the uptake, use and loss of nitrogen by tea plants, and iv) nitrogen flows within the soil. CUPPA-Tea was then calibrated and validated using measured tea yields from Tanzania and Kenya. RESULTS AND CONCLUSIONSAfter integrating a wide range of nitrogen algorithms, the model explained 79% of the variation in annual yields within a nitrogen and irrigation experiment in Tanzania and a fertilizer experiment in Kenya. The slope of the relationship was 0.84 and 0.73 respectively, the root mean square error was 660 kg ha−1 and 507 kg ha−1, and the modelling efficiency was 0.77 and 0.75 respectively. The model predicted that in the absence of N application, tea yields would be higher from a site with a high rather than a low soil organic content. By contrast, at high levels of mineral N application, the yield response in the model was not sensitive to the soil organic content. Hence within the model, a site in Tanzania with a low soil organic content of 1.6% showed a greater yield response to applied mineral N than a site in Kenya where the soil organic carbon was 4.0%. The model also predicted small losses of N from the cropping system through denitrification and leaching due to the acidic soil conditions (pH < 4.5) and an assumed tea rooting depth between 300 and 500 cm. In Tanzania, irrigation was predicted to result in around 10% higher nitrogen uptake than under unirrigated conditions. SIGNIFICANCEThe use of the CUPPA-Tea model can be useful in supporting decision making and improving the accuracy of tea yield estimates, as well as predictions of N fate within the soil-plant-atmosphere continuum.

Mung Bean Is Better Than Soybean in the Legume–Wheat Rotation System for Soil Carbon and Nitrogen Sequestration in Calcareous Soils of a Semiarid Region

Small changes in soil aggregates-associated organic carbon and soil nitrogen (N) can induce huge fluctuations in greenhouse gas emissions and soil fertility. However, there is a knowledge gap regarding the responses to long-term continuous rotation systems, especially in N-fixing and non-N-fixing crop wheat in terms of the distribution of soil aggregates and the storage of soil carbon (C) and N in aggregates in the semiarid calcareous soil of Central China. This information is critical for advancing knowledge on C and N sequestration of soil aggregates in rainfed crop rotation systems. Our aim was to determine which legume (soybean (Glycine max)– or mung bean (Vigna radiata)–wheat (Triticum aestivum) rotation practice is more conducive to the formation of good soil structure and C and N fixation. A 10-year field experiment, including a soybean (Glycine max)–winter wheat (Triticum aestivum) rotation (SWR) with yield increments of 2020 compared to 2010 achieving 18.28% (soybean) and 26.73% (wheat), respectively, and a mung bean (Vigna radiata)–winter wheat rotation (MWR) achieving 32.66% (mung bean) and 27.38% (wheat), as well as farmland fallow, was conducted in Henan Province, China. The soil organic carbon (SOC), N content in the soil, and the soil aggregates were investigated. Legume–wheat rotation cropping enhanced the proportion of the &gt;2 mm soil fractions and reduced the &lt;0.053 mm silt + clay in the 0–40 cm soil profile. In the 0–30 cm soil layer, the SWR had a greater increment of the &gt;2 mm aggregate fractions than the MWR. Two legume–winter wheat rotations enhanced the C and N sequestration that varied with soil depths and size fractions of the aggregate. In contrast, the MWR had greater SOC stocks in all fractions of all sizes in the 0–40 cm soil layers. In addition, the greater storage of N in the macro-, micro-, and silt + clay fractions was observed in the 0–30 cm layers; the MWR enhanced the C/N ratios in most of the size aggregates compared with the SWR. The MWR cropping system is more beneficial to the formation of good soil structure and the increasement of C and N reserves in soil. Thus, these findings show that mung bean, in contrast with soybean in the legume–wheat rotation system of a semiarid temperate zone, may offer soil quality improvement.

The importance of soil and water for increasing the strength of ceramic products

The article presents data reflecting the physicochemical and physical and mechanical properties of the soil used as a raw material for the production of brick products. The authors describe the data reflecting the fundamental difference between electro activated water underlying the proposed technological method, compared with ordinary water. When analysing the results of studying the chemical composition of the soil, the average value of the hydrogen index, which is a soil solution, corresponds to 7.6, and the average amount of acid anions and the average amount of basic ion-cations composition is compared with the average amount of basic ion-cations (6.48: 2.7) turned out to be 2.4 times more. The authors make the conclusion that the soil reserve used for production is acidic.

Ideotype breeding for crop adaptation to low phosphorus availability on extensive organic farms.

Organic farming in extensive production regions, such as the Canadian prairies have a particularly difficult challenge of replenishing soil reserves of phosphorus (P). Organic grains are exported off the farm while resupply of lost P is difficult due to limited availability of animal manures and low solubility of rock organic fertilizers. As a result, many organic farms on the prairies are deficient in plant-available P, leading to productivity breakdown. A portion of the solution may involve crop genetic improvement. A hypothetical 'catch and release' wheat ideotype for organic production systems is proposed to (i) enhance P uptake and use efficiency but (ii) translocate less P from the vegetative biomass into the grain. Root traits that would improve P uptake efficiency from less-available P pools under organic production are explored. The need to understand and classify 'phosphorus use efficiency' using appropriate indices for organic production is considered, as well as the appropriate efficiency indices for use if genetically selecting for the proposed ideotype. The implications for low seed P and high vegetative P are considered from a crop physiology, environmental, and human nutrition standpoint; considerations that are imperative for future feasibility of the ideotype.