Amount Of Available Phosphorus Research Articles

Responses of soil enzymatic activities and microbial biomass phosphorus to improve nutrient accumulation abilities in leguminous species

Fertilizers application are widely used to get a higher yield in agricultural fields. Nutrient management can be improved by cultivating leguminous species in order to obtain a better understanding of the mechanisms that increase the amount of available phosphorus (P) and potassium (K) through fertilizer treatments. A pot experiment was conducted to identify the leguminous species (i.e., chickpea and pea) under various fertilizer treatments. Experimental design is as follows: T0 (control: no fertilizer was applied), T1: P applied at the level of (90 kg ha−1), T2: (K applied at the level of 90 kg ha−1), and T3: (PK applied both at 90 kg ha−1). All fertilizer treatments significantly (p < 0.05) improved the nutrient accumulation abilities and enzymes activities. The T3 treatment showed highest N uptake in chickpea was 37.0%, compared to T0. While T3 developed greater N uptake in pea by 151.4% than the control. However, T3 treatment also increased microbial biomass phosphorus in both species i.e., 95.7% and 81.5% in chickpeas and peas, respectively, compared to T0 treatment. In chickpeas, T1 treatment stimulated NAGase activities by 52.4%, and T2 developed URase activities by 50.1% higher than control. In contrast, T3 treatment enhanced both BGase and Phase enzyme activities, i.e., 55.8% and 33.9%, respectively, compared to the T0 treatment. Only the T3 treatment improved the activities of enzymes in the pea species (i.e., BGase was 149.7%, URase was 111.9%, Phase was 81.1%, and NAGase was 70.0%) compared to the control. Therefore, adding combined P and K fertilizer applications to the soil can increase the activity of enzymes in both legume species, and changes in microbial biomass P and soil nutrient availability make it easier for plants to uptake the nutrients.

Effect of Nitrogen and Sulphur Levels on Growth Attributes and Yield of Indian Mustard [Brassica juncea (L.) Czern &amp; Coss] in Vindhya Plateau Region of Madhya Pradesh, India

In the Rabi season of 2022, a field experiment was conducted in the Vindhya plateau region of Madhya Pradesh at the agricultural field of SAGE University Bhopal. The objective was to investigate the impact of nitrogen and sulfur nutrition on the growth and yield of Indian mustard (Brassica juncea L.). The experimental soil, characterized as sandy loam with a slightly alkaline pH, exhibited good drainage. Despite having a moderate amount of available phosphorus and potassium, the soil had low levels of organic carbon and nitrogen, with a low electrical conductivity of 1.65 dS/m (1:2, soil: water).&#x0D; The experiment comprised 27 nitrogen and sulfur treatment combinations in a split-plot design with three replications. The treatments included three nitrogen levels (100, 120, and 140 kg ha-1) and three sulfur levels (20, 40, and 60 kg ha-1). The mustard variety Giriraj was cultivated, and the study focused on evaluating the effects of these treatments on growth, yield, and nutrient uptake.&#x0D; Results indicated that various mustard crop attributes, such as plant height, number of green leaves-1, branches plant-1, siliqua plant-1, seeds siliqua-1, and 1000 seed weight, as well as yields (biological, seed, and oil yield), exhibited significant increases with rising nitrogen levels from 100 kg N ha-1 to 140 kg N ha-1. Similarly, applying 60 kg S ha-1 resulted in maximum plant height, number of green leaves, dry matter production, oil yield, and the highest net returns among sulfur levels.&#x0D; The combination of 140 kg N ha-1 and 60 kg S ha-1 proved to be cost-effective, leading to increased yields, net returns, and a higher B:C ratio compared to other nitrogen and sulfur levels. Therefore, this study recommends the application of 60 kg S ha-1 and 140 kg N ha-1 for enhancing mustard crop yields, net returns, and the benefit-cost ratio.

Phosphate-Solubilizing Bacteria: Advances in Their Physiology, Molecular Mechanisms and Microbial Community Effects.

Phosphorus is an essential nutrient for all life on earth and has a major impact on plant growth and crop yield. The forms of phosphorus that can be directly absorbed and utilized by plants are mainly HPO42- and H2PO4-, which are known as usable phosphorus. At present, the total phosphorus content of soils worldwide is 400-1000 mg/kg, of which only 1.00-2.50% is plant-available, which seriously affects the growth of plants and the development of agriculture, resulting in a high level of total phosphorus in soils and a scarcity of available phosphorus. Traditional methods of applying phosphorus fertilizer cannot address phosphorus deficiency problems; they harm the environment and the ore material is a nonrenewable natural resource. Therefore, it is imperative to find alternative environmentally compatible and economically viable strategies to address phosphorus scarcity. Phosphorus-solubilizing bacteria (PSB) can convert insoluble phosphorus in the soil into usable phosphorus that can be directly absorbed by plants, thus improving the uptake and utilization of phosphorus by plants. However, there is no clear and systematic report on the mechanism of action of PSB. Therefore, this paper summarizes the discovery process, species, and distribution of PSB, focusing on the physiological mechanisms outlining the processes of acidolysis, enzymolysis, chelation and complexation reactions of PSB. The related genes regulating PSB acidolysis and enzymatic action as well as genes related to phosphate transport and the molecular direction mechanism of its pathway are examined. The effects of PSB on the structure and abundance of microbial communities in soil are also described, illustrating the mechanism of how PSB interact with microorganisms in soil and indirectly increase the amount of available phosphorus in soil. And three perspectives are considered in further exploring the PSB mechanism in utilizing a synergistic multi-omics approach, exploring PSB-related regulatory genes in different phosphorus levels and investigating the application of PSB as a microbial fungicide. This paper aims to provide theoretical support for improving the utilization of soil insoluble phosphorus and providing optimal management of elemental phosphorus in the future.

Morphological and Molecular Characterizations of Arbuscular Mycorrhizal Fungi and Their Influence on Soil Physicochemical Properties and Plant Nutrition.

Pulses are considered a remarkable and stable source of nutrients, which are being presently extensively cultivated and consumed in different parts of the world. Pulses belong to the family Leguminosae and are a rich source of nutrients such as phosphorus (P) and nitrogen (N) for best growth via symbiotic relationship with bacteria and AMF (arbuscular mycorrhizal fungi). The aim of the current study was evaluating the influence of AMF diversity associated with various pulses (French bean, mung bean, kidney bean, peas, soybean, peanuts, and grams). Furthermore, AMF characterization was done using morphological features of spores and sequencing of the rDNA gene, which confirmed the existence of 10 different AMF taxa. Among the different genera, the genus Glomus was observed to be the most dominant with 30% species followed by Gigaspora (22%), Sclerocystis (12%), Acaulospora (8%), Rhizophagus and Septoglomus (7%), Diversispora (5%), and Claroideoglomus, Archaeospora, and Ambispora (3%). Furthermore, soil physicochemical analysis and percentage of AMF colonization results revealed the fact that the phosphorus content (inversely proportional to the AMF diversity) was a determining factor of AMF diversity. The highest amount of available phosphorus (62.825 mg kg-1) in the district Swabi resulted in a low rate of AMF colonization (6.66 ± 11.54%) with a comparatively higher rate of AMF colonization (50.66 ± 1.15%) found in the soil of the district Chitral having a low phosphorus content (17.3 ± 7.6 mg kg-1). Nutrient uptake by pulses including nitrogen (2.4 ± 1.3%), phosphorus (13.5 ± 7.6 mg kg -1), potassium (99.5 ± 25.8 mg kg -1), zinc (1.4 ± 0.5 mg kg -1), moisture (2.3 ± 1.3%), crude fats (5.6 ± 2.8%), ash (4 ± 1.2%), and proteins (13.6 ± 9.01%) determined the fact that AMF species diversity is positively correlated to the plant mineral nutrition. From the current study, it is concluded that AMF inoculation to the soil fields is beneficial to ensure the sustainability and productivity of pulse crops in diverse environmental conditions without polluting the soil.

Impact of Biochar Application on Chemical and Microbial Properties of Soil

Biochar is a carbonaceous solid compound formed by high-temperature of organic waste. The quality of biochar produced is determined by pyrolysis conditions and the type of raw materials. This study focused on the evaluation of the impact of biochar application on soil chemical and microbial properties. Four types of biochar from corn cobs, sawdust, mud press, and rice hull were produced and their chemical composition (pH, Organic Matter, Organic Carbon, Total Nitrogen, Carbon: Nitrogen Ratio, Available Phosphorus, and Exchangeable Potassium) was analyzed. A pot experiment with five treatments [T1 - Pure Soil; T2 – Soil + corn cob biochar; T3 – soil + sawdust biochar; T4 – soil + mud press biochar; T5 – soil + rice hull biochar] replicated three times was arranged in a completely randomized design (CRD). An equal amount of soil was placed in pots and mixed with biochar at a ratio of fifty grams (50g) per one-thousand grams (1000g) of soil. A total of fifteen experimental pots were used in the study where each pot contains a soil-biochar mixture of one-thousand five-hundred grams (1500g). Pearson’s correlation coefficients were used to determine how the soils applied with biochar are affected after sixty days of incubation and determine how biochar sources were related. All four biochar from rice hull, corn cobs, mud press, and sawdust are all alkaline and contain comparable amounts of organic matter, organic carbon, pH, soil nitrogen, available phosphorus, and exchangeable potassium. The result of the study showed that biochar application significantly improved soil pH, soil organic matter content, soil organic carbon, and soil nitrogen content. Soils amended with biochar showed comparable amounts of available phosphorus and exchangeable potassium. The application of biochar in soils therefore can be considered a potential solution to enhance soil fertility for sustainable crop production.

Изучение вопроса о закупке красящих композиционных материалов на основе неорганического и органического сырья

The article states that one of the biggest problems of modern agriculture is to prevent the irreversible loss of fertile land on earth and to provide agriculture with new land. In this regard, it has become an urgent problem to use natural resources efficiently and restore damaged lands with various means and methods. In the studies conducted to solve the problem, the process of obtaining composite materials with fertilizer-ameliorant properties, which is of particular importance in increasing soil productivity and plant height, using inorganic and organic raw materials, was studied. It has been established that only applying fertilizers to ecologically damaged soils does not give positive results, because the structure and physical-chemical properties of the soils are damaged, and complex measures must be taken to restore them. The more intensive feeding of the plant with phosphorus with the participation of the magnesium element leads to the formation of water-resistant aggregates, which, as a result, percolation and infiltration decrease, and the amount of available phosphorus in the soil increases.

Partial substitution of chemical fertilizer with organic fertilizer and slow-release fertilizer benefits soil microbial diversity and pineapple fruit yield in the tropics

The partial substitution of chemical fertilizers with organic fertilizer and slow-release fertilizer is an effective approach for improving crop yield and soil quality. However, few studies have paid close attention to pineapples in the tropics. Here, a 2-year field experiment was conducted to elucidate the differences in pineapple rhizosphere soil microorganisms, bulk soil chemical characteristics, and pineapple fruit yield under different fertilization treatments (CK: no fertilizer application; FP: conventional chemical fertilizer application; OPT: reduced chemical fertilizer application; OPTO: based on OPT, with organic fertilizer replacing 20 % of nitrogen (N); OPTS: based on OPTO, with slow-release fertilizer replacing 15 % of N), and the links between soil microorganisms and soil chemical properties and pineapple fruit yield were analyzed. Compared with FP, OPT, OPTO and OPTS treatments significantly increased bulk soil pH and organic matter (OM) content while reducing the amount of available phosphorus (AP), available potassium (AK), nitrate nitrogen (NO3−) and ammonium nitrogen (NH4+); in addition, they also highly increased the bacterial diversity index and pineapple yield (P < 0.05). It was found that Proteobacteria, Actinobacteria, Chloroflexi and Acidobacteria were the four major bacterial phyla (relative abundances >10 %) in all treatments, while Ascomycota was the main phylum of fungi. Specifically, the OPTS treatment increased the abundance of Chloroflexi, Acidobacteria and Basidiomycota but decreased the abundance of Proteobacteria, Actinobacteria and Ascomycota. Correlation analysis found that bulk soil pH, OM, AP, AK, NO3− and NH4+ levels were all important factors influencing the formation of the rhizosphere soil microbial community. Overall, the OPTS treatment resulted in relatively high soil nutrient content, microbial diversity and the number of beneficial microorganisms, which increased pineapple yield. Therefore, OPTS can be used as a high-yield and sustainable fertilization method for pineapple.

Evaluation of biostimulation, bioaugmentation, and organic amendments application on the bioremediation of recalcitrant hydrocarbons of soil

In the present work, the operational conditions for improving the degradation rates of Total Petroleum Hydrocarbons (TPHs) in contaminated soil from a machinery park were optimized at a microcosms scale along a 90-days incubation period. In this study, bioremediation strategies and an organic amendment have been tested to verify the remediation of soil contaminated with different hydrocarbons, mineral oils, and heavy metals. Specifically, designed biostimulation and bioaugmentation strategies were compared with and without adding vermicompost. The polluted soil harboring multiple contaminants, partially attenuated for years, was used. The initial profile showed enrichment in heavy linear alkanes, suggesting a previous moderate weathering. The application of vermicompost increased five and two times the amounts of available phosphorus (P) and exchangeable potassium (K), respectively, as a direct consequence of the organic amendment addition. The microbial activity increased due to soil acidification, which influenced the solubility of P and other micronutrients. It also impacted the predominance and variability of the different microbial groups and the incubation, as reflected by phospholipid fatty acid (PLFA) results. An increase in the alkaline phosphatases and proteases linked to bacterial growth was displayed. This stimulation of microbial metabolism correlated with the degradation rates since TPHs degradation' efficiency after vermicompost addition reached 32.5% and 34.4% of the initial hydrocarbon levels for biostimulation and bioaugmentation, respectively. Although Polycyclic Aromatic Hydrocarbons (PAHs) were less abundant in this soil, results also decreased, especially for the most abundant, the phenanthrene. Despite improving the degradation rates, results revealed that recalcitrant and hydrophobic petroleum compounds remained unchanged, indicating that mobility, linked to bioavailability, probably represents the limiting step for further soil recovery.

Effects of restoration strategies on wetland: A case‐study of Xinqiang River National Wetland Park

AbstractAccurately understanding the characteristics of a wetland ecological restoration plant communities and their species diversity relationships is the key to improving wetland management and biodiversity protection. To see the effects of restoration strategies implemented in Xinqiang River National Wetland Park, China, we studied 4 models for ecological restoration, namely protection and conservation (PC), reasonable utilization (RU), restoration and reconstruction (RR) and the building of constructed wetland (CW). We then analyzed the features of the plant communities, species diversity and soil properties, and carried out a correlation analysis between plant communities and the species diversity. Finally, we selected four key communities and analyzed their features and soil properties using a symmetric matrix. Results showed that the soil in the PC model had the highest amount of available phosphorus, available nitrogen and pH value. The soil had higher moisture content in the RU model and CW model than the other 2 models. Based on the correlation analysis, we found that there are obvious common characteristics among different ecological restoration types, that is, the diversity characteristics of tree layer, shrub layer and herb layer have obvious differentiation characteristics. We identified four features of the community characteristics that could improve species diversity: SA, TH, HH and SCD. The results of this study have provided a theoretical basis that there is a coupling relationship between ecological community characteristics and species diversity. The above coupling results have practical significance for maintaining good ecological structure and diversity protection.

Variation in Soil Physico-Chemical Properties in Temperate Forests of Khatling Valley, Western Himalaya, India

The current study seeks to understand the physico-chemical properties of soil along different altitude in Khatling valley of Western Himalaya. Four sites were examined for different physico-chemical characteristics between 1500-3500m amsl. The investigation found that the soils at all of the study sites were acidic and had a sandy loam texture. The range of the water holding capacity and moisture content values across the research area was 35.59±4.22 to 38.91±3.97% and 14.77±0.12 to 17.39±1.13% respectively. In the studied area the values for total nitrogen ranged from 0.19±0.02 to 0.37±0.04%, available phosphorus (10.23±2.45 to 15.97±2.63kg ha-1), available potassium (122.95±17.58 to 212.90±19.67kg ha-1), organic carbon (0.92±0.35 to 3.09±0.63%) and organic matter (1.58±0.60 to 5.32±1.09%) respectively. Organic carbon and total nitrogen displayed a positive correlation with altitude (r = 0.992 and r = 0.865, respectively) but a negative correlation with soil depth. In contrast, there was a negative association between altitude and the amounts of available phosphorus (r = -0.941) and potassium (r = -0.941). The available phosphorus indicates a positive relation with the depth of soil, whereas available potassium did not exhibit a consistent pattern with depth. This finding of this study suggest that soil physico-chemical properties vary with altitude and soil depth.

Blended Amendments: A Sustainable Approach for Managing Nutrient Deficiency in Rice Fields

The application of chemical fertilizer provides absorbable soluble macronutrients for increasing rice yield while reducing the availability of micronutrients and occasionally halting nitrogen mineralisation in the soil. To lessen some of these undesirable effects of chemical fertilization, an effort has been made to prepare blended soil organic amendments by mixing organic materials like rice straw, dried cow-dung and compost prepared from eco-friendly wastes from the kitchen, backyard garden and dried cow-dung mixed in the ratio 1:2:2. Such prepared amendments were applied in the rice field by growing three high-yielding rice cultivars Dikhow, Chandrama and Naveen, in three different rice cropping seasons, pre-monsoon (Ahu), monsoon (Sali) and summer (Boro) during 2015-2016 and 2016-2017 for studying soil properties, crop growth and yield. The key finding of the investigation was that the soil amended with chemical fertilizer showed improvement in soil moisture compared to unamended soil in all three rice fields. However, chemically fertilized soil exhibited lower amounts of available phosphorus, available potassium, diethylenetriaminepentaacetic acid (DTPA) extracted iron and copper in Ahu field, DTPA extracted iron, copper and zinc in Sali field and immobilizing nitrogen in Boro field than blended amendments. Overall, chemical fertilizer + rice straw displayed more available nitrogen and yield in Ahu field, whereas, chemical fertilizer + dried cow dung showed the highest amount of zinc and copper along with the highest yield in Sali rice field and chemical fertilizer+compost had better moisture and soil organic carbon amounts with an ideal acidic pH supporting maximum yield in Boro rice field.

Phosphorus availability increases pathobiome abundance and invasion of rhizosphere microbial networks by Ralstonia.

Soil disease-suppressiveness depends on complex interactions among pathogens, native microbiota, and physicochemical properties, while these interactions remain understudied. Comparing field and microcosm experiments, we investigated the significance of these interactions in disease emergence or suppression using structural equation modelling (SEM) and receiver operating characteristic curve (ROC) analyses. We observed significant differences in the relative abundance of pathogenic and beneficial microbes, alpha and beta diversity indices between disease-conducive and -suppressive rhizosphere soils. The pathogenic (Ralstonia) and beneficial (Bacillus) taxa dominated disease-conducive and -suppressive rhizosphere soils, respectively. Moreover, the co-occurrences of Ralstonia with native microorganisms were positive and negative in the disease-conducive and -suppressive soils, respectively. These results suggest the supportive (Rudaea) and suppressive (Enterobacter, Bacillus) role of indigenous microbes in the invasion of soil and plant systems by Ralstonia. The SEM and ROC analysis predicted that Ralstonia invaded rhizospheric microbial networks and caused peanut wilt under high than low soil phosphorus conditions. Our results suggest the importance of soil phosphorus availability in altering the microbial interactions, thus leading to soil invasion by Ralstonia. Thus, we conclude by saying that feeding soil with high amounts of available phosphorus could deplete plant-beneficial microbes and increase the pathobiome abundance that may compromise plant health.

Influence of Anthropogenic Impact on Alteration in the Alluvial Soil Fertility Indicators

The article presents studies on establishing the influence of anthropogenic impacts on alluvial soils of agricultural lands. To solve the problem set, tasks were determined to estimate the degree of damage caused to soils of agricultural lands as a result of the soil humus layer loss or closure. These tasks included establishing the degree of alteration in soil fertility indicators for agricultural lands in regard to pH volume; organic matter content; degree of provision with K2O and P2O5 accessible forms as a result of violating technology of the damaged land stripping and reclamation. Nature of changes in granulometric (grain) and micro-aggregate soil composition is demonstrated. Study objects included agricultural land territories with soil samples of alluvial granular soil taken at the depth of 0-5 cm and 5-20 cm. Necessity is demonstrated to study in detail the agroecological assessment of land use systems and the development of differentiated measures ensuring reproduction of soil fertility, crop growth and territory ecological sustainability. Negative processes are manifested to a varying degree on agricultural land in most administrative regions of Russia including agricultural land in the Orel Region, which requires creation of the ecologically sustainable land use system. Since transformation of compounds entering the ecological system primarily occurs in the soil, which acts as a filter and as the factor of transformation and accumulation of the entering substances, agrobiological features of soil composition and properties make it extremely sensitive to anthropogenic impact. As a result of scientific research, it was revealed that the studied area experienced a decrease in soil fertility main indicators of the alluvial soils and destruction (deterioration) of the fertile soil layer as a result of exposure to anthropogenic influence. Rates of decrease in the organic matter content in soil layer as a result of the soil humus layer damage are shown. Significant fluctuations in the amount of exchangeable potassium in the soils of anthropogenically damaged agricultural lands are established. Degree of decrease in the amount of available phosphorus in soils without humus layer is revealed. Significant alteration in the granulometric (grain) composition of the damaged land soil is proved.

USEPA LEAF methods for characterizing phosphorus and potentially toxic elements in raw and thermally treated sewage sludge

Biologically available phosphorus supports plant growth but can also cause environmental contamination. Sequential extraction methods, such as Hedley fractionation, are the most widely used to assess available phosphorus from solids. However, such methods exhibit numerous deficiencies. The USEPA Leaching Environmental Assessment Framework (LEAF) is a tiered system developed to evaluate releases of Potentially Toxic Elements (PTEs) from solids. This study compared the Hedley fractionation method to the LEAF pH-dependent, parallel batch tests (Method 1313) and dynamic leaching column test (Method 1314) to assess the bioavailability of phosphorus. The three methods were applied to wastewater treatment plant sludge before and after thermal treatment. Both methods revealed similar qualitative trends, namely that thermal treatment transformed phosphorus into less immediately available forms. However, the Hedley and LEAF methods were inconsistent in the forms and amounts of available phosphorus recovered from the solids. The Hedley method left 40% of phosphorus unextracted from sludge and 20% from ash, suggesting that it may be less appropriate for organic materials. Moreover, only 2 of the 6 Hedley phosphorus pools were within environmentally relevant pH conditions. Furthermore, the Hedley method overpredicted the readily available phosphorus. In contrast, the LEAF methods allowed for a more detailed analysis of phosphorus availability - while simultaneously assessing PTEs - across a controlled pH range. Moreover, LEAF used simpler procedures and provided more easily interpreted results. Thus, LEAF facilitates more robust and valuable assessment of organic and inorganic solids being considered for land application.

Soil quality and proposal for fertility improvement of arable soil in Rasina District

During the regular control of soil fertility in the Rasina District, it was established that the plots of land were distributed across Vertisol, Eutric Cambisol and Fluvisol types of soils, and to a lesser extent on Pseudogley and Ranker. The tested samples had different textures - sandy loam and loam, clay-sandy loam and clay loam, and clay. Plots of land that were of very acidic and acidic reactions were predominant, with medium amounts of humus, very low amounts of available phosphorus, and high amounts of available potassium. High or very high cation absorption capacity was found in about half of the examined fields; a deficient content of exchangeable Ca was recorded in 22% of plots and that of exchangeable Mg in 16% of plots, while an unfavorable Ca/Mg ratio was measured in 44% of plots. The overall sensitivity to acidification was mainly moderate (50.6% of plots) and strong (20.2% of plots). Very high concentrations of mobile Al, which could be toxic to plants, were found in 5 field plots.

Економічна ефективність збалансованих схем удобрення картоплі столової макро- і мезоелементами на темно-сірому опідзоленому ґрунті за використання рідких фосфоровмісних добрив

Економічна ефективність збалансованих схем удобрення картоплі столової макро- і мезоелементами на темно-сірому опідзоленому ґрунті за використання рідких фосфоровмісних добрив

Влияние органических и минеральных удобрений на динамику питательных веществ в орошаемых серо-бурых почвах Апшеронского полуострова

The introduction of various fertilizer rates led to a change in the amount of nutrients in the irrigated gray-brown soils of the Absheron Peninsula. The amount of nitrates and ammonia absorbed in soils under legumes increased with increasing fertilization rates. In the course of the experiment, the maximum amount of available phosphorus in the control compared with the soils under legumes was recorded at the early stages of their development. In connection with the formation of vegetative and generative organs of plants during the growing season, the use of mobile phosphorus from the soil by plants increased. The minimum amount of mobile phosphorus in the soil was observed when legumes were fully ripe. A similar process was observed in the content of exchangeable potassium in the soil.

Main elements of nutrition content in the soil for maize crops, depending on the predecessors and methods of soil treatment

The article presents data on the study of the main nutrition elements in the soil under maize crops, depending on the predecessors and methods of soil treatment in the conditions of ordinary Chernozem. The object of research is aKrasnodarsky 194MVhybrid of maize. Variants: 1. Fallow arable land (control); 2. Lupine as green manure; 3. Peas as green manure; 4. Binary sowing of lupine and peas as green manure; 5. Soy as green manure. The experiment was repeated three times, field placement was randomized, and area of each was 120 m². Agrotechnics of maize cultivation in the experiment corresponded to the recommendations for this zone. Green manure was plowed in during its reproduction phase. In the variants with green mass plowing to a depth of 23–25 cm, the largest amount of nitrate nitrogen was in the soil layer 0–20 cm. In the specified soil horizon, before sowing maize, the content of nitrate nitrogen ranged, depending on the variant, from 24.7 mg/kg to 42.8 mg/kg. In the soil layer 20–40 cm, the amount of nitrogen was lower, just 19.4–29.5 mg/kg. Similar dependence was observed for maize during its flowering phase. Tillage methods had almost no effect on the accumulation of nitrate nitrogen in the upper soil layer (0–20 cm). As in all the variants, the differences in this indicator were within the experimental error. However, the content of nitrate nitrogen during the growing season was different. The greatest amount of it was observed during the spring period, both in versions with plowing to a depth of 25–28 cm and in versions with blade loosening to a depth of 10–12 cm. The smallest amount of available phosphorus, regardless of the method of soil preparation, in the layer 0–20 cm was on fallow arable land – 122 mg/kg during the sowing period and 104 mg/kg during the flowering period. In variants with cultivation of legumes as green manure, the content of available phosphorus in the specified horizon was significantly chigher, being 147–171 mg/kg. The highest content of exchangeable potassium was provided by lupine – 209–213 mg/kg in the 0–20 cm soil layer, and lupine sown together with peas – 196–207 mg/kg. The minimum amount of exchangeable potassium was 143–146 mg/kg in fallow arable land, depending on the method of soil treatment.

Cải thiện năng suất lúa OM5451 trên vùng đất phèn nặng thông qua sử dụng phân urea humate, kali humate và phân hỗn hợp NPK chậm tan có kiểm soát tại Hậu Giang

The study is aimed to change traditional practices of rice cultivation (using conventional, unbalanced fertilizers and too many seeds) of farmers in acid sulfate soils with 2 rice crops/year in Hoa An commune, Phung Hiệp district, Hậu Giang province. Cultivation model under the improved farming method (improved model) using NPK slowly released fertilizer, urea humate, potassium humate and reduced seeding amount were conducted through two rice crops (Winter-Spring 2018 - 2019 and Summer-Autumn 2019) with an area of ​​3000 m2 / model. The results showed that the improved model had a higher pHH2O, the amount of available phosphorus in the soil increased, the Al3+ and H+ content decreased, significantly different from the control model. The productivity of the improved model rice was (6.19 tons/ha) significantly higher than that of the control model (5.67 tons/ha) in the Winter-Spring crop. In the following crop (Summer-Autumn crop) there was no statistically significant difference in rice yield between the improved model (5.57 tons/ha) and the control model (5.05 tons/ha). The improved model helped farmers save 30% of the seed sowing seed, 50% of the amount of N and P fertilizers, and gain higher profits (by 5.4 and 3.5 million VND/ha, respectively for Winter-Spring and Summer-Autumn crops).

Response of bacterial compositions to soil biochemical properties under mulching-intensive management in a Phyllostachys edulis forest

Phyllostachys edulis (Moso bamboo) is of great significance to forestry in China. Increased attention has been paid to exploring the role of underground ecology, especially soil microorganisms, in the cultivation and ecology of Moso bamboo. Mulching-intensive management can benefit Moso bamboo forests with low yields. However, the response of soil bacteria to changes in soil biochemical properties after intensive mulching is still unclear. In this study, the responses of the soil bacterial composition to changes in soil biochemical properties under different management conditions were analysed by sampling a bamboo forest under four management conditions: control, mulching, alternation and long-term mulching. The results showed that mulching and alternation could improve the diversity of soil bacteria at the phyla and genera levels, while long-term mulching had the opposite result. The relative abundances of Proteobacteria, Actinomycetes, TM7 and Bacteroides were lower in the control plots than in the other plots, while those of AD3, Verruca and GAL15 were higher. The results also showed that C (carbon), N (nitrogen) and P (phosphorus) accumulated rapidly in the mulching, alternation and long-term mulching plots due to the extensive application of organic and compound fertilizer. Soil acidification became obvious with the extension of mulching time. An increase in the C/N led to a decrease in substrate soil quality. Large amounts of total phosphorus (TP) and NO3−-N accumulated under long-term mulching, while the amounts of available phosphorus (AP) and NH4+-N decreased. The change in the microbial biomass carbon (MBC) content was consistent with that in the MBC/microbial biomass nitrogen (MBN), which decreased significantly in both the mulching plots and the long-term mulching plots, and alternation ameliorated the trend. MBC/MBN and pH were positively correlated with the bacterial composition at the genus level, while TP, NO3−-N, soil organic carbon (SOC) and water-soluble organic carbon (WSOC) were negatively correlated. The results showed that the soil bacteria did not benefit from the availability of relatively low-quality (high C/N) substrates, which was reflected by an imbalance in the soil bacteria composition under long-term mulching. Therefore, mulching is beneficial to the improvement of soil biochemical properties and the development of bacterial communities in a short period, but long-term mulching results in a significant decline compared with the other three management conditions. The soil biochemical environment and bacterial composition of Moso bamboo forest can be properly elevated by alternation, which is a necessary supplement to mulching and long-term mulching.