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Soil fertility is one of the crucial factors for agriculture, whose main objective is to increase production. Therefore it is extremely important to know the nutritional requirement of cultivars. Fertility-focused studies are essential for fertilization recommendations in all regions, especially in banana cultivation which is a very demanding plant in fertility. Thus, the present work aimed to evaluate soil fertility, emphasizing the quantification of nutrients necessary to ensure the agricultural productivity of musa sp. The research was developed at laudelino farm, municipality of Teotônio Vilela/Alagoas, between 2019 and 2020, where soil amotragens were performed, randomly collected in the 0-20 cm depth layer, removing 1 kg of soil and sent to the soil laboratory of the Campus of Engineering and Agrarian Sciences (CECA) of the Federal University of Alagoas (UFAL) located in the municipality of Rio Largo-AL, for chemical analysis. The hydrogenic potential (pH), phosphorus (P) and potassium (K+) accessible were analyzed; calcium (Ca+2) and tradable magnesium (Mg+2); saturation by exchangeable aluminum (m%), cation exchange capacity CTC at pH 7.0 (T); base saturation (V%) and; organic matter (OM). As a result of the analysis, the following results were obtained: pH content (5.6); OM (14.1 g/kg) P (5.0 mg/dm³) K (110 mg/dm³), Ca2+ (3.42 cmolc/dm³), Mg2+ (2.53 cmolc/dm³); Al3+ (0.00 cmolc/dm³), H (4.41 cmolc/dm³), and CTC (T) (10.73 cmolc/dm³); m (0.0 %) and V (59 %). Based on the above results, it is suggested the application of 1,103 kg of limestone in order to increase the base saturation to 70%, in addition to the addition of 50 kg/ha of N and 343.5 kg/ha of P2O5 and 96.7 kg/ha of K2O. It is worth mentioning that their applications in the soil must be carried out through sources of 837.8 kg/ha of triple superphosphate; 161.2 kg/ha of potassium chloride and 111 kg/ha of urea. It is also essential to add 30 to 50 t/ha of organic matter, such as bovine manure to the soil, aiming at better utilization of the material by crops.

Identification of the factors controlling the migration of hexavalent chromium (Cr (VI)) in soil can provide valuable information for pollution control and risk assessment. In this study, we assessed the processes of transportation and migration of Cr (VI) in soil by batch and column experiments. Breakthrough curves were used to examine the mobility of Cr (VI) in soil columns. Most of them could be described by a typical S-shaped curve. The Yoon–Nelson model and Thomas model were applied to predict the behavior of Cr (VI) in soil and obtained parameters to characterize the rate and capacity of adsorption. It was observed that all obtained parameters changed along with soil properties. Moreover, stepwise multiple regression and grey correlation analysis were used to determine the main control factors by evaluating the relationship between soil properties and dynamic or static parameters. The results showed Fe oxide content was the key factor no matter in static or dynamic adsorption while soil texture had a great influence on the transportation of Cr (VI) in soil columns. Also, in the actual situation, the external input condition should not be ignored. Our research provides meaningful information for authorities to develop better soil management and remediation strategies.

Purpose: Nitrogen (N) cycle is one of the key biogeochemical cycles in terrestrial ecosystems. Global climate change and soil management practices have disrupted the soil N cycling processes due to increased water and N limitations. Biochar is a soil amendment and improves soil–plant water and N retentions. However, it is uncertain to what extent biochar pyrolysis temperature would affect soil N transformations under two soil moisture regimes. This study aimed to explore how pyrolysis temperature would affect biochar properties and subsequently soil N transformations through a short-term laboratory incubation study at two moisture levels. Materials and methods: An incubation study was carried out for 5 days. Biochar added to the soil at a rate of 5% (w/w) was produced under six different pyrolysis temperatures (e.g., 500, 600, 650, 700, 750, and 850 °C). We used 15N natural abundance (δ15N) of inorganic N (NH4+-N and NO3−-N) to assess the potential of biochar materials in facilitating forest soil N transformations at two different soil moisture levels of 50% and 65% water holding capacity (WHC). Results and discussion: Pyrolysis temperature significantly increased cumulative nitrification and N mineralization initially, peaked between 600 and 700 °C and decreased thereafter. However, both cumulative nitrification and N mineralization were significantly lower in the biochar-amended soils than those of the control soil, with significantly lower δ15N of NH4+-N and δ15N of NO3−-N. The 65% WHC had higher cumulative nitrification and N mineralization compared with those in 50% WHC. This study highlights that application of biochar would reduce N losses and improve soil N retention particularly for forest soil. Conclusions: The present study highlights the importance of biochar pyrolysis temperatures for their use as soil conditioner to increase soil N retention. An optimum pyrolysis temperature range of 600–700 °C was identified for improving soil nitrification and N mineralization under the laboratory incubation conditions.

Abstract This study investigates the adsorption and dissipation of glyphosate and the formation/dissipation of AMPA in non-tilled (NT) and conventionally tilled (CT) soil at 0–5 and 5–20 cm depth. Glyphosate adsorption was mainly related to the different NT and CT soil properties (clay and amorphous Al oxides), whereas an effect of the soil management could not be identified. Glyphosate dissipation was initially fast, and it slowed down later. The initial glyphosate concentration in NT soil at 0–5 cm was significantly lower than the dose applied due to the interception by the weeds and crop residues. AMPA began to form early after treatment and persisted longer than glyphosate. The DT50 range was 8–18 days for glyphosate and 99–250 days for AMPA. Longer glyphosate and AMPA DT50 were observed in NT soil compared to CT soil but, for glyphosate, the difference was significant only at 5–20 cm. Higher glyphosate and AMPA concentrations were detected in NT than in CT soil at the end of the study at 0–5 cm. The differences in glyphosate and AMPA DT50 and persistence were mainly attributable to the influence of different NT and CT soil characteristics. However, other factors could have contributed to the different glyphosate and AMPA dynamics between the soils, like glyphosate wash-off from crop residues on NT soil with the rainfall, the delayed glyphosate return to the soil by weed root exudation or weeds decomposition, and the NT soil compaction which may have reduced the microbial degradation of glyphosate at low concentrations. Graphic abstract

Nitrous oxide (N2O) emissions from soils have been widely studied in the literature — mostly with the chamber method — due to the importance of this gas to climate change. Emissions of N2O derive from biological reactions and are controlled by soil parameters, which are by nature heterogeneous (i.e., “hot spots” for N2O emissions) — a source of uncertainty in chamber-based studies. Spatial variation in N2O fluxes has been assessed in the literature, but the information is still needed for contrasting soil management practices (e.g., tillage) and for specific bioclimatic situations [e.g., non-growing seasons (NGS) under cold weather]. Here, we subsampled daily N2O data to assess within-plot and between-block spatial variation from an agronomic experiment under conventional tillage (CT) and no-tillage (NT), identifying if patterns differ between growing seasons (GS) and NGS datasets. Within-plot spatial variation in N2O fluxes was a small source of uncertainties, but half of the comparisons in GS datasets presented a slope different from 1 for the regression of N2O averages from two vs. one chamber per plot — a source of uncertainty mitigated when within-plot duplication occurred during N2O “hot moments”. Between-block spatial variation in N2O emissions was much larger than within-plot errors — an effect more accentuated for NGS and CT than GS and NT datasets. Decreasing the number of sampled blocks resulted in averages that did not represent the N2O daily average of the whole field, but exceptions occurred. The methodology proposed here may be used in other locations, after appropriate verification, for improved planning and maximization of the resources associated with N2O measurements.

The fate of hydrophilic, hydrophobic, and insoluble fractions extracted from 13C-labelled maize straw and their use for the formation of bacterial and fungal-derived amino sugars (AS) were monitored during a 40-day incubation of upland and paddy soils. The highest sequestration of C in the AS pool was present in the hydrophilic fraction in both soils (1.1–1.4% of input C). Bacterial community in upland soil utilized the hydrophilic fraction the most for the formation of AS, whereas fungi used the hydrophobic fraction, suggesting that bacteria and fungi have different substrate preference. In contrast, fungi used similar portions of all fractions for AS formation in the paddy soil, which could be a substrate utilization strategy under anoxic conditions. Sequestration of microbial-derived C, formed from the added fractions, was lower in paddy than in upland soils (0.7–1.1% vs. 1.2–1.4%), while total AS content showed the opposite trend (493–509 mg kg−1 in paddy vs. 387–405 mg kg−1 in upland soils). This was attributed to the 1.5 times lower microbial activity in paddy than in upland soils based on the relative incorporation of 13C into total MBC. Thus, sequestration of microbial-derived C from various organic C sources is closely related to substrate quality, but soil management and its properties modulate the microbial utilization of substances with various hydrophobicity.

To access the process of nitrogen mineralization in soil, the buried-bag technique was used among traditional agroforestry systems in the Bhabhar belt of Kumaun Himalaya. The present study, determined the relationship between various parameters of N-mineralization with agroforestry systems, seasons and soil depths. Season and soil depth have significantly (p

The investigation of various nutrition systems in hemp plays an influential role in improving its production. An experiment was conducted in University of Birjand, Iran, during 2013-2014, in which manure (0, 10, 20, and 30 t.ha-1 of cow manure) was considered as the main plot and the combination of nitrogen (0, 50, and 100 kg N ha-1 as urea) with phosphorus (0 and 80 kg P ha-1 as triple superphosphate) fertilizers was considered as factorial in subplots. The type of soil fertility management had no significant effect on the percentage of female plants. Applying 20 t.ha-1 of manure plus 100 kg N ha-1 produced the highest biological yield, seed, and leaf extract. The highest oil content was obtained by applying a maximum of 50 kg N ha-1 without the use of phosphorus. The 30 t ha-1 manure plus 100 kg N ha-1 increased the leaf harvest index and decreased seed harvest index. Nitrogen consumption also increased the seed oil content and yield. Phosphorus increased the biomass and extracts of seed and leaves, also biological, seeds and oil yield. It seems hemp responds well to the combined application of nitrogen fertilizer and animal manure, while its response to P fertilization was limited.

Soil organic matter (SOM) is considered to be the most important part of the soil. C and N and their forms are most often used to evaluate SOM. In the last decades, C indices have begun to be used to assess soil quality for C changes in SOM due to the different soil management. Since C cycle is closely related to N, there is an assumption that N indices will be sensitive to N changes in SOM under the different soil management. The objective of the study was to evaluate the extent of C and N indices on C and N changes in SOM (in Rendzic Leptosol) under the different soil management practices (1. G: grass and no fertilization - as control; 2. T: tillage; 3. T+FYM: tillage + farmyard manure; 4. G+NPK3: grass + NPK 125-50-185 kg ha-1; 5. G+NPK1: grass + NPK 100-30-120 kg ha−1) in a productive vineyard (Nitra-Dražovce; Slovakia) during the period of 13 years. The results showed that the soil organic carbon (SOC) was reduced by 26% compared to G because of intensive cultivation on one hand, but on the other hand, in T + FYM treatment no significant changes in SOC over the 13 years of the experiment were observed. A higher labile carbon (CL) content was in G+NPK3 then follows: G+NPK1 > G > T+FYM > T for topsoil. In topsoil, carbon lability increased after a higher level of mineral fertilization, while in subsoil after intensive cultivation. The values of CPI for topsoil decreased in the following order: G+NPK1 > T+FYM > G+NPK3 > T. Based on CMI values, intensive C changes in the SOM due to the soil management practices were observed in T treatment. The highest accumulation of carbon and decomposable organic matter occurred in G+NPK3. Incorporation of FYM, and both rates of NPK increased values of NMI by 45, 47 and 36% respectively compared to T for topsoil. The highest values of the NPI were detected because of farmyard manure application and mineral fertilization at a higher rate for topsoil and because of intensive cultivation, as well as plowing of FYM for subsoil.

The objectives of this study were to evaluate the stability of aggregates, and quantify the contents and stocks of total organic carbon (TOC), and granulometric and humic fractions of soil organic matter (SOM). Four management systems were evaluated: (1) a no-tillage system (NTS) implemented 5 years ago (NTS5); (2) NTS implemented 17 years ago (NTS17); (3) conventional tillage system (CTS) implemented 20 years ago (CTS20); and (4) native Cerrado vegetation. For each system, five undeformed and five deformed soil samples were collected from the 0.00–0.05, 0.05–0.10, 0.10–0.20, and 0.20–0.40 m layers. The weighted mean diameter (WMD), TOC, stock of carbon (StockC), organic carbon particulate (OCp), organic carbon associated with minerals (OCam), stock of OCp, stock of OCam, carbon stock index, carbon management index (CMI), organic carbon in the fulvic acid fraction (FAF), humic acid fraction (HAF), and humin fraction were quantified. The WMD and CMI values increased as the soil management intensity decreased. The adoption of the NTS increased the WMD and the contents, stocks, and proportions of TOC in the more labile granulometric and humic (FAF/HAF) fractions of the SOM. The WMD, CMI, granulometric and chemical fractionation of the SOM were more efficient than the TOC and StockC in identifying the differences between the management systems. Due to the higher contents of the more labile fractions of SOM, the granulometric and chemical fractionation of SOM in the NTS5 and NTS17 systems had higher values of WMD and CMI than the CTS20 system.

QUALIDADE DA BERINJELA IRRIGADA COM ÁGUAS SALOBRAS VIA GOTEJAMENTO CONTÍNUO E POR PULSOS LUCAS FARIAS DAMASCENO1; LOUISE ROSA MONTE BELO2; HANS RAJ GHEYI3; ALIDE MITSUE WATANABE COVA4; GEOVANI SOARES DE LIMA5 E LARA DE JESUS MARQUES6 1 Mestrando em Engenharia Agrícola da Universidade Federal do Recôncavo da Bahia, Rui Barbosa, 710, Centro, 45330-000, Cruz das Almas, Bahia, Brasil. E-mail: lucas_farias13@hotmail.com 2 Engenheira Agrônoma, Universidade Federal do Recôncavo da Bahia, Rui Barbosa, 710, Centro, 45330-000, Cruz das Almas, Bahia, Brasil. E-mail: louiserosamonte@gmail.com 3 Professor Visitante da Universidade Federal do Recôncavo da Bahia, Rui Barbosa, 710, Centro, 45330-000, Cruz das Almas, Bahia, Brasil. E-mail: hgheyi@gmail.com. 4 Pós-Doutoranda no Programa de Pós-graduação de Engenharia Agrícola da Universidade Federal do Recôncavo da Bahia, Rui Barbosa, 710, Centro, 45330-000, Cruz das Almas, Bahia, Brasil. E-mail: alidewatanabe@yahoo.com.br 5 Programa de Pós-Graduação em Engenharia Agrícola, Universidade Federal de Campina Grande, Aprígio Veloso, 882, Universitário, 58428-830, Campina Grande, Paraíba, Brasil. E-mail:geovani.soares@pq.cnpq.br 6 Estudante de Agronomia da Universidade Federal do Recôncavo da Bahia, Rui Barbosa, 710, Centro, 45330-000, Cruz das Almas, Bahia, Brasil. E-mail: lara_marques8@hotmail.com 1 RESUMO Devido suas propriedades medicinais e por ser um alimento rico em antioxidantes, o consumo da hortaliça berinjela vem crescendo. Durante o cultivo da berinjela, o manejo da água e do solo são fatores que podem influenciar a qualidade do fruto. Assim, objetivou-se com este trabalho analisar as características físico-químicas do fruto da berinjela ‘Florida Market’ irrigada com águas salobras por gotejamento contínuo e pulsos. O experimento foi conduzido em ambiente protegido com delineamento experimental em blocos casualizados, em esquema fatorial 2 x 4, com cinco repetições. Os tratamentos consistiram de duas formas de aplicação de água: gotejamento contínuo e pulsos, com quatro níveis de condutividade elétrica da água – CEa (0,3 (controle); 1,5; 3,0 e 4,5 dS m-1). Foram avaliadas as variáveis: massa fresca do fruto, teor de sólidos solúveis totais, pH da polpa, acidez total titulável e relação sólidos solúveis totais/acidez total titulável. Com o incremento da salinidade da água de irrigação o teor de sólidos solúveis totais (+3,60%) e acidez total titulável (+9,87%) aumentaram, enquanto a relação de sólidos solúveis totais/acidez total titulável (-4,53%) e a massa fresca do fruto diminuíram. A interação entre a salinidade e a forma de aplicação da água não influenciou as características físico-químicas do fruto. Palavras-chave: Solanum melongena L., salinidade, sólidos solúveis, acidez titulável. DAMASCENO, L. F.; BELO, L. R. M.; GHEYI, H. R.; COVA, A. M. W.; LIMA, G. S. de; MARQUES, L. de J. QUALITY OF EGGPLANT FRUIT IRRIGATED WITH BRACKISH WATER UNDER CONTINUOUS DRIP AND PULSE IRRIGATION 2 ABSTRACT Due to its medicinal properties and to be a functional food rich in antioxidants, the eggplant vegetable consumption has been increasing. During eggplant cultivation, water and soil management are factors that can influence fruit quality. Therefore, this work aimed to analyze the physico-chemical characteristics of the fruit of the eggplant ‘Florida Market’ irrigated with brackish water under continuous drip and pulse irrigation. The experiment was conducted in protected environment in a randomized block design, adopting a 2 x 4 factorial scheme, with five replicates. The treatments consisted of a combination of two forms of application of brackish water: continuous drip and pulses, with four levels of water salinity - ECw (0.3 (control); 1.5; 3.0 and 4.5 dS m-1). The variables evaluated were fresh weight of the fruit, total soluble solids content, pH of the pulp, total titratable acidity and the ratio of total soluble solids/total titratable acidity. With the increase in salinity of irrigation water the content of total soluble solids (+3.60%) and total titratable acidity (+9.87%) increased, while the ratio of total soluble solids/total titratable acidity (-4.53%) and fresh fruit mass decreased. The interaction between salinity and the form of water application did not influence the physico-chemical characteristics of the fruit. Keywords: Solanum melongena L., salinity, soluble solids, titratable acidity.

The objective of this work was to evaluate the variation in total and particulate organic carbon contents, carbon vertical stratification, and sensitivity index of organic matter fractions in soils with organic residues arranged in alleys in an agroforestry system, with and without use of fire, in the Caatinga biome, in Brazil. The experiment was conducted in a split-plot arrangement with four replications, with the factor fire in the plots, and the factor organic residues in the subplots. The organic residues used consisted of Gliricidia sepium plants; G. sepium plants and carnauba processing residue; G. sepium plants and bio-compost; and G. sepium plants, carnauba processing residue, and bio-compost, which were evaluated in three soil layers. The alleys with carnauba processing residue, G. sepium plants, and bio-compost presented a better maintenance of particulate, and mineral-associated organic carbon contents. Thus, the agroforestry management in alleys using these three residues was efficient for the maintenance of labile and recalcitrant organic matter compartments. Particulate organic carbon was more sensitive to changes in soil management than total organic matter content, in all alleys, presenting higher sensitivity indexes. O objetivo deste trabalho foi avaliar a variação no carbono orgânico total e particulado, relação de estratificação de C, e índice de sensibilidade dessas frações da MOS sob resíduos orgânicos em aléias em um sistema agroflorestal, com e sem uso do fogo na Caatinga. Por meio de experimento em parcelas subdivididas com quatro repetições, onde nas parcelas foi avaliado o fator fogo, e nas subparcelas foi avaliado o fator resíduos orgânicos nas aléias, com as variações de gliricídia isolada, gliricídia com bagana de carnaúba, gliricídia com biocomposto e gliricídia, bagana de carnaúba e biocomposto, sob três profundidades. Nas aléias com uso combinado dos resíduos da bagana de carnaúba, gliricídia e biocomposto houve maior conservação tanto do conteúdo de C orgânico particulado quanto do C associado aos minerais. Assim, o manejo agroflorestal em aléias utilizando a combinação dos três resíduos foi eficiente na conservação de uma matéria orgânica lábil e mais estável. Verificou-se também que o carbono orgânico particulado em todas as aléias foi mais sensível às modificações realizadas no manejo do solo em relação ao conteúdo total da MOS, no qual observou-se maiores índices de sensibilidade dessa fração. &nbsp

Nitrogen overfertilization is a common horticultural practice in central Chile, leading to the risk of nitrate leaching and contamination of aquifers and groundwater. The aim of the present study was to evaluate the effect of organic amendments on NO3 - leaching. Three sites with different management systems were selected: Agroecological (AE, 3-yr agroecological management), Transition (TR, starting agroecological management), and Conventional (CN, traditional conventional management). Two lettuce (Lactuca sativa L.) growing cycles (autumn-winter and spring-summer) were implemented at each site. Nutrition at AE and TR was based on organic fertilizers and microorganisms, and inorganic N fertilizers were used at CN. The pore water was sampled at the beginning and at the end of each cycle at the 70 cm depth. Lettuce yields and unit weight were measured. There was a significant effect of the site and time of sampling (both p = 0.000) on the NO3 - concentration in leached water. At the beginning of the first cycle, nitrate leaching was 2.2 times higher at TR and CN (370 ± 81 mg L-1) compared with AE (163 ± 54 mg L-1), reflecting the loss of previously accumulated soil N. Afterward, leaching at CN remained higher than at AE and CN, significantly varying between sampling times; however, it decreased by 37% to 80% compared with the initial measurement. Leaching at both AE and TR remained stable within a low range of 38 to 96 mg L-1. Results showed that organic soil management is able to maintain a low rate of nitrate leaching in the soil compared with conventional management.

Organic phosphorus (Po) plays an important role in tropical forest nutrition on strongly-weathered soils. However, of its role in Eucalyptus nutrition little is known. For this purpose, soil P forms were determined by NaOH-Na2EDTA extraction and 31P nuclear magnetic resonance spectroscopy (31P NMR) at 10 sites of Eucalyptus plantations in Brazil. The objectives were (1) to determine the amounts and forms of soil Po; (2) to build a structural model of the soil P cycle to provide quantitative estimates of the transformation processes of soil P. Soil P was found to consist of large amounts of Monoesters-P (on average 43.7 mg kg−1) followed by Diesters-P in the form of DNA (on average 4.2 mg kg−1), as well as containing high reserves of Pi species (on average 101.6 mg kg−1 of the ortho-P; 2.7 mg kg−1 of the pyrophosphate). Thestructural model indicated that the P cycle is regulated by clay, soil organic carbon, total P and pH. High total Po concentrations (on average 48 mg kg−1) reveal a high potential of P supply to Eucalyptus trees, in which Diester-P (DNA) would be the main source P for the available P pool. The close interconnection between ortho-P, pyrophosphate, DNA and Monoester-P compounds provides evidence of a strong influence of soil biological activity on the distribution and accumulation of these P compounds and therefore on the availability of P. Thus, these results are relevant to establish soil fertility management strategies for low-fertilizer input Eucalyptus systems in soils with low fertility.

Considering human activities are the most direct and important factors leading to the accumulation and loss of soil black carbon (BC), a detailed understanding of soil BC in different functional zones and reasonable soil management are the keys to determine whether soil is the carbon source or carbon sink. In this study, carbon concentrations and isotope compositions of black carbon (BC%, δ13CBC) and organic carbon (OC, δ13COC) were determined in topsoil from different functional zones (roadside grass verges, parks, residential areas, mines, arable lands, woodlands and wastelands) in urban and suburban of Beijing, China. The organic carbon (OC) content in soils of the urban area (averaging 1.67%) is higher than in suburban areas (averaging 1.05%). Black carbon is not evenly distributed across different functional zones, but is more concentrated and variable in urban areas (0.11–2.43%, averaging 0.73%) than in suburban areas (0.03–0.70%, averaging 0.18%). The ratios of BC% to OC% in suburban areas (0.04–0.40) are smaller than in urban areas (0.15–0.98). The δ13CBC of topsoil (–26.35…–20.85‰) reflects that coal combustion has a strong impact on soil BC accumulation in Beijing. The carbon isotope differences between OC and BC of the suburban and urban topsoils are positive (averaging +0.56‰) and negative (averaging –0.41‰), respectively. This suggests that urban areas are seriously influenced by human activities which lead to a large amount of fossil fuel combustion, but suburban areas have received a uniform deposition of atmospherically transported finer BC aerosols.

The capacity of soil to store carbon (C) and emit carbon dioxide (CO2) into the atmosphere primarily depends on soil management practices. It is essential to understand the impact of management strategies on the soil organic carbon (SOC) content and labile organic carbon (LOC) fraction. The impacts of 24‑year-long organic and inorganic nitrogen (N) treatments on SOC, KMnO4-oxidizable organic carbon and its fractions (highly labile organic carbon (HLOC), moderately labile organic carbon (MLOC), low labile organic carbon (LLOC) and nonlabile organic carbon (NLOC)), and a carbon management index (CMI) were investigated under a continuous maize cultivation system in a long-term experiment in Guizhou, Southwest China. Six fertilizer treatments were included: no fertilizer input (CK), chemical fertilizer alone (NPK), 25% N through farmyard manure (FYM) plus 75% N through chemical fertilizer (1/4N-M+3/4N-CF), 50% N through FYM plus 50% N through chemical fertilizer (1/2N-M+1/2N-CF), FYM plus chemical fertilizer (MNPK) and FYM alone (M). We used the LOC content and CMI value to assess the effects of long-term combinations of FYM and chemical fertilizers at different rates on the SOC pool in various soil layers (0–20, 20–40, 40–60, 60–80, 80–100 cm) and to identify the most suitable integrated treatment. The results showed that the application of organic fertilizer generally increased the SOC content, the LOC fraction, and the CMI values in different layers, especially the surface layer, compared to the CK and NPK fertilization treatments. The SOC content and LOC fraction decreased with increasing soil depth. The significant relationship between the LOC fraction, CMI value, LOC available ratio of carbon (LOC-AR), and soil parameters showed that these values can be used to sensitively assess soil quality and SOC changes in the system. Considering the comprehensive effects on the SOC content, LOC fraction, CMI value, AR value, etc., the 1/4N-M+3/4N-CF and 1/2N-M+1/2N-CF treatments showed the greatest influence on carbon sequestration and soil productivity; therefore, these could be the best options for maize cropping systems in this region.

Process-based biogeochemical models can be used to simulate soil nitrous oxide (N2O) fluxes and maize yields and draw insights on yields improvement and climate change mitigation options. We compared both observed and DeNitrification-DeComposition (DNDC) simulated soil N2O fluxes and maize yields. We used DNDC model to simulate soil N2O fluxes and maize yields under four soil fertility treatments (inorganic fertiliser, animal manure, animal manure + inorganic fertiliser and control,) replicated thrice for 1 year in Central Highlands of Kenya. We sampled soil N2O fluxes using static chambers installed in each plot. We analysed soil N2O using gas chromatography and calculated cumulative fluxes using trapezoidal rule linear interpolation between sampling dates. DNDC showed poor results in simulating daily N2O fluxes (157.16% ≤ normalised root mean square error (nRMSE) ≤ 324.01% and 0.90 ≤ modelling efficiency (NSE) ≤ 0.96), good to excellent performance in simulating cumulative annual soil N2O fluxes (6.16 ≤ nRMSE ≤12.86 and 0.63 ≤ NSE ≤ 0.86) and good to excellent performance in simulating maize yields (1.15% ≤ nRMSE ≤13.86% and 0.51 ≤ NSE ≤ 0.88) across all soil fertility treatments. The DNDC model had good to excellent performance in simulating cumulative soil N2O fluxes and crop yields across treatments. Though the model captured yield-scaled N2O fluxes and N2O emission factors across treatments, they were underestimated under manure treatment. There is a need to continue calibrating the DNDC model for improved capture of daily N2O fluxes and uptakes on Kenyan soils.

A total of 713 research papers about field monitor experiments of heavy metals in farmland and urban soils in China, published from 2000 to 2019, were obtained. A meta-analysis was conducted to evaluate the level of China's heavy metal pollution in soils, mainly focusing on eight heavy metals. It was found that the average concentrations of cadmium (Cd), lead (Pb), zinc (Zn), copper (Cu), mercury (Hg), chromium (Cr), nickel (Ni), and arsenic (As) in China were 0.19, 30.74, 85.86, 25.81, 0.074, 67.37, 27.77 and 8.89 mg/kg, respectively. Compared with the background value (0.097 mg/kg), the Cd content showed a twofold (0.19 mg/kg) rise in farmland soils and a threefold (0.29 mg/kg) rise in urban soils. The decreasing order of the mean Igeo was Cd (1.77) > Pb (0.62) > Zn (0.60) > Cu (0.58) > Hg (0.57) > Cr (0.54) > Ni (0.47) > As (0.28). Nearly 33.54% and 44.65% of sites in farmland and urban soils were polluted with Cd. The average concentrations of eight heavy metals were not sensitive change in recent two decades in farmland and urban soils. The average Pn values for urban (2.52) and farmland (2.15) soils showed that heavy metal pollution in urban soils was more serious than that in farmland, and the middle Yangtze River regions, where industrial activity dominates, were the most polluted. The meta-analysis comprehensively evaluated the current pollution situation of soil heavy metal, and provided important basis for soil management and environment prevention in China.

The spatial variability of soil chemical properties is affected by factors of soil formation and human activities. Understanding their spatial variability will improve agricultural production, reduce environmental problems (e.g., soil pollution, offsite effects), and achieve sustainable agroecosystems. The main objective was to study the spatial variability of pH, soil organic matter, available phosphorus, and available potassium using univariate and multivariate methods in cropland fields in eastern Croatia. For the study, 169 (0-30 cm) soil samples were collected in a 911 ha study area. The results showed that soils had slightly acidic pH, adequate available phosphorus and potassium values for crop production, and low soil organic matter concentration. The variability was high in available phosphorus and low in pH. Soil pH, soil organic matter, available phosphorus, and potassium nugget/sill ratio was 0.00, 2.79, 18.68, and 22.08, respectively. Auxiliary variables increased the accuracy of the predictions. Soil organic matter levels were below the recommendable, and this is very likely an anthropogenic effect, even though the intrinsic process influences soil organic matter. The heterogeneous distribution of phosphorus and potassium highlighted the necessity of fertilization in some areas. For the sustainability of agroecosystems, adaptable site- specific soil management strategies need to be implemented.

Background Hardsetting soils are considered problem soils due to its behavior of becoming hard and unbearable to cultivate not until rewetted. Few investigations were conducted in this kind of problem soil; hence, information about biomass yield and nutrient uptake is still elusive. This study investigated the impact of potentially hardsetting soil on the biomass yield and nutrient uptake of sweet corn under no-tillage cultivation system with varying fertilization treatments. Results The application of full NPK + 1 Mg ha−1 VC increased stover and grain yield by 26–106% and 11–135%, respectively. Approximately 64% and 112% of sweet corn stover and grain yield increased when treated with full NPK. Highly significant quadratic relationship (P P Conclusion Application of organic amendment in combination with inorganic fertilizer could be a sustainable production strategy on sweet corn production system in potentially hardsetting soil under no tillage through enhanced nutrient uptake and biomass accumulation.

Soil is the crucial biological sink of methane, which is an important and potent greenhouse gas. The extensive biochar application in soil has also aroused interests in its influence on soil methane emissions. However, although numerous studies have paid attention to the methane flux from the biochar amended soil, the research efforts of biochar effects on methanotrophs mediating the methane consumption in soil still lag behind and need to be re-examined. Especially, studies of the nonconventional methanotrophs for atmospheric and anaerobic methane oxidation, which have rapidly developed in recent years, deserve much attention. Here, we literately reviewed the proceedings about the biochar effects on conventional, atmospheric, and anaerobic methanotrophs in soil, respectively. Biochar plays a great role in methanotroph communities through soil characteristics controlling and redox reactions. Key physical soil characteristics such as porosity, aggregation, and moisture and chemical parameters such as soil pH, nitrogen, and metal oxides are confirmed to be altered by the biochar amendment for the regulation of methanotrophs. Soil methane oxidation is thereby regulated by biochar amendment. This review improved our understanding of the biochar function in greenhouse gas regulation and provided a scientific basis for better soil management with biochar application.

It is necessary to know the effect of organic matter on soil physical properties for successful soil management. A short-term incubation study was carried out to investigate the effects of differen...

The decrease in soil productivity and quality caused by the continuous and abusive use of mineral fertilizers makes necessary to adopt more sustainable agricultural soil management strategies that help to maintain soil edaphic fertility. In light of these considerations, we have evaluated the effect of organic vs. inorganic fertilization on soil microbial communities, soil quality, and crop yield in a melon crop. The following treatments were tested: i) aerobic sewage sludge from a conventional wastewater treatment plant (WWTP) using aerobic bacteria (SS); ii) aerobic sewage sludge from a WWTP using a bacteria-microalgae consortium (B); iii) N-P-K mineral fertilizer (M); iv) a treatment in which 50% of the N was contributed by SS and 50% by mineral fertilizer (M + SS); v) a treatment in which 50% of the N was contributed by B and 50% by mineral fertilizer (M + B); and vi) a no-fertilized control soil. Melon yield and fruit quality were determined in addition to several soil physical, chemical, biochemical and microbiological parameters. Organic fertilizers (SS and B) increased the percentage of soil water-stable aggregates (52 and 60% respectively) as well as the content of organic C (18 and 31%), water soluble C (21 and 41%), N (15 and 41%) and available P content (41 and 82%) compared to inorganic fertilization. They also stimulated bacterial and fungal abundance to a greater extent than mineral fertilizers (189 and 242% vs 85%, and 57 and 122% vs 29%, respectively), as well as soil respiration, and dehydrogenase, β-glucosidase, phosphatase, urease, and glycine aminopectidase activities. The analysis of principal components with parameters linked to soil quality clearly showed that organic fertilizers cause a greater improvement in soil characteristics and microbial community than mineral fertilizers. Results demonstrate that organic and combined fertilization could be used as substitutes for nitrogen mineral fertilizers in melon crop, since these treatments led to similar melon production and quality while improving soil characteristics and microbial population size and activity.

It is no doubt that soils are among the Earth’s largest terrestrial reservoirs of carbon pool and hold potential for its sequestration and thus, soils can serve as potential way of mitigating the ever-increasing atmospheric CO2 concentration. However, the stability and flux of soil organic carbon are affected in response to changes that are being driven by forms of environmental and anthropogenic factors. Therefore, to establish carbon sequestration potential of soils, an in-depth scientific evaluation that would provide mapping of and speciation of carbon chemical forms, as well as factors influencing the persistence of carbon in soils are key to the process which are beyond quantitative measurements that are conventionally implemented under different land use and/or soil management. This involves soil chemistry, physics, biology, and microbiology. Hence, this short review communication highlights portions of soil chemistry and physics as well as soil biology and microbiology that have not been given attention in determining and/or underpinning decisions on carbon sequestration potential of soils.

Soil fertility management is of great importance for farmers. The use of synthetic nitrogen (N)-fertilizer increased by 20 fold in the last 50 years to feed the increasingly hungry population. This study aims to enrich the plant soil with nitrogen content (NH4NO3 fertilizer in soil) using the low-temperature and low-pressure plasma [without H2 and catalyst]. Subsequently, we used plasma N-enriched soil for plant (radish and tomato) growth. We investigated the germination percentage, seedling growth, seedling weight, phytohormones and antioxidant activity of radish and tomato plants after treatment with plasma N-enriched soil and compared with control soil and soil + commercial N-fertilizer. The plasma N-enriched soil treatment results in significant growth enhancement for both radish and tomato plants. Further, substantial changes in phytohormone and antioxidant levels were observed for the plants grown in plasma N-enriched soil compared to control soil and soil + commercial N-fertilizer. The energy consumption (EC) for total N-fixation was 12 MJ mol−1. EC for ammonia and nitrate fixation was 17 and 41 MJ mol−1, respectively, without H2 gas. Further to understand the plasma chemistry, we performed 1D simulation using COMSOL Multiphysics® software. This study showed that direct N-fixation in the soil by plasma could be used as fertilizer for the plants and open a new window for future decentralized N-fertilizer production at the farm site.

In recent years, common bean in Brazil has become interesting to precede the growing of off-season cotton due to its short cycle. This study was carried out in a Red Latosol in Chapadão do Sul, MS and aimed to select among the attributes of the evaluated soils, those with the best linear and spatial correlation, to explain the variability of grain yield of common bean in the soil layers of 0 - 0.10 m (layer 1) and 0.10 - 0.20 m (layer 2), sampled in a grid of 121 georeferenced points (spacing of 5 meters between points). The soil chemical attributes were determined: pH, carbon (C), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), aluminum (Al), and the sum of bases (SB). The analysis of these data was carried out using statistical and geostatistical techniques that made it possible to verify that for the grain yield of common bean, the multiple regression analysis indicates that approximately 20% of its variation is attributed to the variation in the chemical attributes of the soil presented in the present study. The chemical attributes pH1, pH2, C1, Ca1, Ca2, Mg1a, Mg2, Al2, SB1, and SB2 have spatial dependence classified mostly as moderate. Both linearly and spatially, C1 stood out as a potential indicator of common bean grain yield when grown under no-tillage.

A remarkable decrease in olive production has been observed in Tunisia since 2000, particularly in the semi-arid region. This downfall was mainly due to a notable change in climatic conditions as a result of wind erosion and over cultivation. The aim of this work was to study the biological, physical, and chemical properties of several semi-arid soils from olive tree fields subjected to different farming practices, such as crop time and type of crop, olive mill wastewater (OMW) application rates, and tillage timing and depth (deep or conventional plowing). We noted that hydraulic conductivity (HC) was proportional to the age of the soil tillage, and the highest values were recorded in the soil cultivated for 100 years, with an average value of 33.05 ± 0.02 mm h−1. An important increment of the iron soil content was observed, especially after the fig tree introduction among the olive trees (12,094 ng μL−1) in 2007. Also, a significant increase of the organic matter (OM) content (up to2.6 mg-OM/g-soil) was identified in soil treated with OMW compared to the lowest OM content (0.83 mg-OM/g-soil) recorded in the soil cultivated since 1901. The bacterial communities of the different soils were characterized by 454 pyrosequencing technology, and showed an important diversity, mainly corresponding to Proteobacteria, Actinobacteria, and Acidobacteria. Many operational taxonomic units (OTUs) are raretons, indicating a high resilience of the soil bacterial communities. Statistical analyses showed significant correlations with the different soil parameters. However, an unexpected correlation was determined between soil respiration and OM (r = − 0.583*), suggesting that OM increases the retention of CO2, a greenhouse gas. The farming techniques analyzed in this study resulted in a reduction of the bacterial diversity, even though the total bacterial biomass augmented.

Degradation of soil micronutrient fertility status is an increasingly serious problem damaging the sustainability of modern agriculture. In this article, an attempt has been made to present some of...

One of the strategies for the recovery of degraded soils is the planting of fast-growing forage species with high biomass production. In this sense, the objective of this research was to evaluate the initial growth of sorghum in degraded soils with organic fertilization and different phosphorus levels. A completely randomized design with a 4 x 3 x 2 factorial arrangement was used, with four soil types, three levels of phosphorus fertilization and two levels of organic fertilization. At 64 days after sowing the characteristics of the initial growth were analyzed: plant height, stem diameter, leaf number and fresh shoot mass. The height was measured by measuring the neck of the plant until the end of the newest fully expanded leaf, measured with the aid of a measuring tape and expressed in centimeters. The diameter of the stem, by means of a digital pachymeter. The application of phosphorus and organic matter in degraded soils is necessary for the initial development of sorghum plants, due to the low availability of this element, caused by the high adsorption of P in the soil colloids. Besides that, the lack of organic matter in the studied soils led to a decrease in the growth of sorghum, therefore, it is concluded that soil management in saline environments is necessary for the application of phosphorus and organic matter for a sustainable and technically viable production.

Geostatistical soil mapping is important for determining spatial distribution of soil parameters. This study was conducted to assess soil spatial distribution of the Horticultural Research Station, Rajikot, Jumla, Nepal. The total 27 samples were collected randomly at a depth of 0-20 cm by using soil sampling auger. A GPS device was used for determination of geographical position of soil sampling points. The collected samples were analyzed following standard analytical methods in the laboratory of National Soil Science Research Centre, Khumaltar. The Arc-GIS 10.1 software was used for the mapping spatial distribution of various soil parameters. The observed data revealed the structure was sub-angular blocky and granular, whereas colour were dark brown to dark grayish brown and dark yellowish brown. The sand, silt and clay content were ranged 24.40-72.10%, 19.40-63.10% and 6.20-14.50%, respectively and categorized loam, sandy loam and silt loam in texture. The soil pH was slightly acidic to moderately alkaline (5.01-8.06), and very low available sulphur (0.59-2.41 mg/kg) and very low to low available boron (0.04-0.87 mg/kg). Moreover, very low to medium available manganese (2.18-13.46 mg/kg), very low to very high available iron (4.50-138.58 mg/kg), and low to medium available magnesium (7.20-177.60.53 mg/kg) and zinc (0.26-1.66 mg/kg). Similarly, medium total nitrogen (0.09-0.22%), medium to high organic matter (1.71-6.26%) and available calcium (1200-3144 mg/kg), medium to very high available phosphorus (3.71-82.4 mg/kg) and potassium (59.37-173.05 mg/kg). Correspondingly, high to very high available copper (0.78-4.20 mg/kg). The determined soil test data can be used for sustainable soil management as well as developing future research strategy in the farm.

Chemical potassium (K) fertilizer is commonly used in apple (Malus domestica L. Borkh) production but K is easily fixed by soil, resulting in reduced K fertilizer utilization and wasted resources. K-solubilizing bacteria (KSB) can cost-effectively increase the soluble K content in rhizosphere soil. Therefore, the objectives were to select high-efficiency KSB from apple orchards under various soil management models and evaluate their effects on apple seedling growth. Maize (Zea mays L.) straw mulching (MSM) increased the total carbon (TC), total nitrogen (TN) and available potassium (AK) in the rhizosphere and improved fruit quality. The number of KSB in the rhizosphere soil of MSM was 9.5×104 CFU g−1 soil, which was considerably higher than that in the other mulching models. Fourteen KSB strains were isolated with relative K solubilizing ability ranging from 17 to 30%, and five strains increased the dry weight per apple seedling. The most efficient strain was identified as Paenibacillus mucilaginosus through morphological observation and sequence analysis of 16S rDNA, named JGK. After inoculation, the colonization of JGK in soil decreased from 4.0 to 1.5×109 CFU g−1 soil within 28 d. The growth of the apple seedlings and the K accumulation in apple plants were promoted by irrigation with 50 mL JGK bacterial solution (1×109 CFU mL−1), but there was no significant increase in the AK content of rhizosphere soil. High-performance liquid phase analysis (HPLC) data showed that the JGK metabolites contained phytohormones and organic acids. Hence, the JGK strain promoted the growth of two-month-old apple seedlings by stimulating function of the produced phytohormones and enhanced K solubility by acidification for apple seedling uptake. This study enriches the understanding of KSB and provides an effective means to increase the K utilization efficiency of apple production.

Made available in DSpace on 2021-06-25T12:33:38Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-10-01. Added 1 bitstream(s) on 2021-07-15T14:36:31Z : No. of bitstreams: 1 S0006-87052020000400623.pdf: 197868 bytes, checksum: 5c72253dabd8ac9ce3daf0820f203157 (MD5) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Oxisols are important soils that have been converted from native vegetation to croplands, and can affect soil biological properties such as microbial biomass and enzyme activity. Thus, the aim of this study was to evaluate the changes on soil microbial biomass and enzyme activity when native vegetation (NV) was converted to cropland (CL), such as maize or sugarcane in six oxisols from Sao Paulo state, Brazil. Soil microbial biomass C (MBC) and N (MBN), and the activity of arylsulphatase, dehydrogenase and fluorescein diacetate hydrolysis (FDA) were assessed in samples collected at 0-0.20 m. In general, MBC was higher under NV than CL (about + 40%), while MBN and FDA did not show a consistent pattern between NV and CL. All soils showed higher values of arylsulfatase (increased from 101 to 717%) and dehydrogenase (increased 15 to 220%) under NV than CL. In conclusion, soil microbial biomass C is usually higher under native vegetation than cropland. Arylsulphatase and dehydrogenase were the attributes that presented better differentiation between native and cropped soils. Univ Estadual Paulista, Fac Ciencias Agr & Vet, Dept Tecnol, Jaboticabal, SP, Brazil Univ Brasil, Programa Posgrad Prod Anim, Descalvado, SP, Brazil Univ Fed Piaui, Ctr Ciencias Agr, Dept Engn Agr & Solos, Teresina, PI, Brazil Univ Estadual Paulista, Fac Ciencias Agr & Vet, Dept Ciencias Exatas, Jaboticabal, SP, Brazil Univ Estadual Paulista, Fac Ciencias Agr & Vet, Dept Tecnol, Jaboticabal, SP, Brazil Univ Estadual Paulista, Fac Ciencias Agr & Vet, Dept Ciencias Exatas, Jaboticabal, SP, Brazil

Biochar as agricultural soil amendment to improve soil physico-chemical properties, crop productivity and sustainable soil fertility management is a well-known practice. A field experiment was conducted to evaluate the effect of biochar on growth and yield components of carrot and selected soil physic-chemical properties. The study was carried by employing a randomized complete block design with factorial arrangement of four level of biochar (0, 4, 8 and 12 tons ha-1) and four level of Nitrogen/Phosphorus (N/P) fertilizer rate (0/0, 60/10, 90/15 and 120/20 kg ha-1) with four replications. Biochar significantly influenced physico-chemical properties of soils, such as bulk density, total porosity, pH, EC, SOC, TN, Av. P and CEC respectively, as compared to control. The results revealed substantial responses to biochar and N/P fertilization on growth and yield components of carrot with increasing level of biochar and N/P fertilizer rate. None of the others yield parameters were significantly affected by the interaction of two factors. From the present study, it can be concluded that dung cake biochar should be applied to enhance and improve soil physical and chemical properties for favourable plant growth.

To provide spatial information on soil resources for sustainable land management in the Mt. Wakakusa Grassland of central-western Japan, we investigated the spatial variation and distribution of selected micronutrients, i.e., Mehlich 3 extractable Fe, Mn, Cu, and Zn (referred as M3-Fe, M3-Mn, M3-Cu, and M3-Zn, respectively), in surface soils (0–5 cm in depth) of the grassland. All micronutrients showed intermediate variability, with coefficients of variation ranging from 26.9 to 48.9%. The M3-Fe (144.0 ± 32.9 mg kg−1) and M3-Mn (204.8 ± 91.3 mg kg−1) contents were relatively high compared with the optimal level exhibited by M3-Cu (1.8 ± 0.5 mg kg−1) and the low level given by M3-Zn (7.8 ± 2.2 mg kg−1). The availability of these micronutrients, except for M3-Zn, showed more significant correlations with the soil mineral phase than with the soil pH and organic matter. Variogram analysis reveals a moderately weak spatial dependency [nugget-to-sill (N/S) ratio = 0.67] for the M3-Zn, while the other micronutrients (M3-Fe, M3-Mn, and M3-Cu) exhibit moderately strong to strong spatial dependencies (N/S ratio = 0.21–0.50). Interpolation maps created in this study demonstrate locations with toxic levels of M3-Fe and M3-Mn and those deficient in M3-Mn and M3-Cu in the study site. Based on these results, a site-specific soil management scheme is recommended in the Mt. Wakakusa Grassland.

Soil management practices with herbicide and fertilizers application may change the soil properties. The amplitude of the change varies according to the soil property and management system. The aim...

The results of studying effects of different fertilizers and basic tillage on biometric and productive parameters of maize hybrids of various ripeness groups are presented.Our purpose was to study effects of different fertilizers and basic tillage on biometric parameters and performance elements in maize hybrids of various ripeness groups.Material and methods. The field experiments were carried out in the Department of Soil Management of Poltava State Agricultural Experimental Station named after N.I. Vavilov of the Institute for Pig Breeding and Agricultural Production of NAAS in 2016–2018.Results and discussion. It was found that mineral fertilizers and microbiological agents contributed to a more intensive growth and development of plants and increased corn grain yields. On average, over the study years, the highest yields from hybrids DZ Latoritsa, Orzhytsa 237 MV and DB Khotyn were obtained with mineral fertilizers at a dose of N40P40K40 kg/ha a.s. on plowing - 8.43 t/ha, 8.27 t/ha and 9.43 t/ha, respectively. The gain related to the control (no fertilizers) was 1.15 t/ha, 0.89 t/ha and 1.54 t/ha, respectively. The same fertilization on blade tillage decreased the yields by 0.31 t/ha, 0.23 t/ha and 0.50 t/ha, respectively. Surface tillage compared with plowing also led to a decrease in the yields by 0.48 t/ha, 0.33 t/ha and 0.86 t/ha, respectively. Growth stimulant Vympel at a dose of 0.5 L/ha in combination with microfertilizers Organic-Balance at a dose of 0.5 L/ha and addition of sticking agent Liposam at a dose of 0.5 L/ha increased the yields of hybrids DZ Latoritsa, Orzhytsa 237 MV and DB Khotyn compared with the control (no fertilizers): on plowing by 0.63–0.74 t/ha, 0.61–0.63 t/ha and 1.02 t/ha, respectively; on blade tillage – by 0.54–0.59 t/ha, 0.43–0.47 t/ha and 0.84 t/ha, respectively; and on surface tillage – by 0.64–0.84 t/ha, 0.80–0.84 t/ha and 0.81–0.85 t/ha, respectively. Microbio-fertilizer Gumina at a dose of 1 L/ha increased the yields by 0.32–0.81 t/ha compared to no fertilizer control, depending on the hybrid and basic tillage.Conclusions. In the Left-Bank Forest-Steppe of Ukraine, mineral fertilization and application of biologicals contributed to a more intensive growth and development of plants and increased the corn grain yields., Приведены результаты исследований по изучению влияния разных систем удобрения и основной обработки почвы на биометрические и продуктивные показатели гибридов кукурузы разных групп спелости.Целью наших исследований было изучение влияния разных систем удобрения и основной обработки почвы на биометрические показатели и формирование элементов продуктивности гибридов кукурузы разных групп спелости.Материалы и методы. Полевые опыты проводили на протяжении 2016–2018 гг. в отделе земледелия Полтавской государственной опытной станции им. Н.И. Вавилова Института свиноводства и АПП НААН.Обсуждение результатов. Установлено, что внесение минеральных удобрений и микробиопрепаратов способствовало более интенсивному росту и развитию растений, повышению урожайности зерна кукурузы. В среднем за годы исследований наибольшая урожайность у гибридов ДЗ Латорица, Оржица 237 МВ, ДБ Хотын была получена при внесении минеральных удобрений дозой N40Р40К40 кг/га д.в. на фоне вспашки – 8,43 т/га, 8,27 т/га, 9,43 т/га. Прирост к контролю (без удобрений) составил 1,15 т/га, 0,89 т/га, 1,54 т/га. В случае применения плоскорезной обработки почвы показатели урожайности на данном варианте удобрения снизились на 0,31 т/га, 0,23 т/га, 0,50 т/га. Проведение поверхностной обработки почвы по сравнению со вспашкой приводило к снижению урожайности на 0,48 т/га, 0,33 т/га, 0,86 т/га соответственно. Использование стимулятора роста Вымпел 0,5 л/га, микроудобрений Органик-баланс 0,5 л/га с добавлением прилипателя Липосам 0,5 л/га способствовало повышению урожайности гибридов ДЗ Латорица, Оржица 237 МВ, ДБ Хотын по сравнению с контролем (без удобрений): на фоне вспашки на 0,63–0,74 т/га, 0,61–0,63 т/га, 1,02 т/га; плоскорезной обработки почвы – 0,54–0,59 т/га, 0,43–0,47 т/га, 0,84 т/га; поверхностной обработки почвы – 0,64–0,84 т/га, 0,80–0,84 т/га, 0,81–0,85 т/га. В случае внесения микробиоудобрений Гумины 1 л/га по сравнению с вариантом без удобрений была получена прибавка 0,32–0,81 т/га в зависимости от гибрида и основной обработки почвы.Выводы. В условиях левобережной Лесостепи Украины внесение минеральных удобрений и биопрепаратов способствовало более интенсивному росту и развитию растений, повышению урожайности зерна кукурузы., Наведено результати трирічних досліджень з вивчення впливу системи удобрення на ріст, розвиток та формування продуктивності гібридів кукурудзи ДЗ Латориця, Оржиця 237 МВ, ДБ Хотин в умовах лівобережного Лісостепу України. Відображено залежність біометричних та продуктивних показників від застосування мінеральних добрив, біопрепаратів та їх сумісності на фоні різних способів основного обробітку ґрунту.

The aim of the study was to determine the effect of soil management systems of Brunic Arenosols on total content of organic carbon and its fraction susceptible to oxidation in comparison with soils under forests. Samples for study were taken from the humus horizon at sites located in forests and soils from little mid-forest cultivated fields (hunting plots). The agrotechnical treatments increased the content of plant-available forms of P, K and Mg in the soils of most hunting plots in comparison to forest soils. In the arable horizon of the hunting plots there was found a varied total content of organic carbon and its fraction susceptible to oxidation. Cultivation of soil in hunting plots caused a decrease in content of total organic carbon as well as its labile and non-labile fraction. To evaluate the carbon transformation in the soil of the cultivated plots against the forest (reference soil), the Carbon Management Index (CMI) was used. The decay rate of soil organic matter in a natural forest was lower than in the agricultural fields. A long-term tillage of Brunic Arenosols contributed to the degradation of the pool of organic carbon in sandy-textured soil.

The present study was conducted to examine the effects of different land-use types on soil quality indices. Surface soils were collected at 0-15 cm and 15-30 cm depth respectively from three land-use types: Cassava field, Oil palm, and Banana plantation. Samples were subjected to physical, chemical, and microbiological analyses using standard methods, and the result were subjected to descriptive statics. The extent of change in soil quality was assessed using soil quality indices as an index for soil fertility management. The result showed that oil palm plantation was highest in soil quality evaluated as compared to Banana and Cassava field. The fertility differences observed across the land use types were due to inherent soil properties such that farming practices that ensure accumulation of organic matter need to be encouraged in order to improve soil productivity. It is recommended that soil fertility management should be site-specific to enhance optimum yield and productivity.

The application of organic materials to soil can recycle nutrients and increase organic matter in agricultural lands. Digestate can be used as a nutrient source for crop production but it has also been shown to stimulate greenhouse gas (GHG) emissions from amended soils. While edaphic factors, such as soil texture and pH, have been shown to be strong determinants of soil GHG fluxes, the impact of the legacy of previous management practices is less well understood. Here we aim to investigate the impact of such legacy effects and to contrast them against soil properties to identify the key determinants of soil GHG fluxes following digestate application. Soil from an already established field experiment was used to set up a pot experiment, to evaluate N2O, CH4 and CO2 fluxes from cattle‐slurry‐digestate amended soils. The soil had been treated with farmyard manure, green manure or synthetic N‐fertilizer, 18 months before the pot experiment was set up. Following homogenization and a preincubation stage, digestate was added at a concentration of 250 kg total N/ha eq. Soil GHG fluxes were then sampled over a 64 day period. The digestate stimulated emissions of the three GHGs compared to controls. The legacy of previous soil management was found to be a key determinant of CO2 and N2O flux while edaphic variables did not have a significant effect across the range of variables included in this experiment. Conversely, edaphic variables, in particular texture, were the main determinant of CH4 flux from soil following digestate application. Results demonstrate that edaphic factors and current soil management regime alone are not effective predictors of soil GHG flux response following digestate application. Knowledge of the site management in terms of organic amendments is required to make robust predictions of the likely soil GHG flux response following digestate application to soil., A pot experiment was set up to evaluate N2O, CH4 and CO2 fluxes from cattle‐slurry‐digestate–amended soils. Digestate stimulated emissions of the greenhouse gases (GHGs) compared to controls. The legacy of previous soil management was a key determinant of CO2 and N2O while edaphic variables, in particular texture, were the main determinant of CH4 flux from soil following digestate application. Results demonstrate that edaphic factors and current soil management regime alone are not effective predictors of soil GHG flux response following digestate application and knowledge of the site management is required to predict soil GHG flux response following digestate application to soil.

Soil fertility management through inorganic fertilizer application in areas with moisture shortage needs due care. The fertilizer application fashion should vary from areas with ample moisture so that the plants can easily access and efficiently use it. Therefore, field experiment was conducted in 2014 and 2015 during the main cropping season under rain-fed condition to evaluate the effect of micro-dose application of N and P fertilizers on sorghum yield at Aybra and Shumshiha sites of Wag-Lasta areas in Amhara Region, Ethiopia where moisture shortage is acute. The treatments were comprised of a factorial combination of three levels of NP i.e. 1), 25% of the recommended NP = 10.25 kg N + 11.5 kg P2O5 ha−1, 2), 50% of the recommended NP = 20.5 kg N + 23 kg P2O5 ha−1 and 3), 75% of the recommended NP = 30.75 kg N + 34.75 kg P2O5 ha−1 and three N application times plus control (without fertilizer) and recommended NP (41 kg N ha−1 and 46 kg P2O5 ha−1). The experiment was laid down in a randomized complete block design with three replications. The fertilizers were applied to the spot where the seed was planted except for the recommended NP which was drilled to the planting rows right before planting. Phosphorus was applied at planting while nitrogen was applied in split as per the treatment setup. All soil and agronomic data were collected and analyzed following the standard procedures. The analysis of variance revealed that application of 30.75 kg N ha−1 and 34.5 kg P2O5 ha−1 (N applied 1/3 at sowing, 1/3 at emergence and 1/3 at 45 days after emergence) increased the grain yield by 122% over the control and 28.4% over the recommended NP and saves 25% of the recommended fertilizer at Aybra. While at Shumshiha-Lasta Lalibela, application of 20.5 kg N ha−1 and 23 kg P2O5 ha−1 (N applied 1/3 at sowing, 1/3 at emergence and 1/3 at 45 days after emergence) increased the grain yield by 174% over the control and 15% over the recommended NP and saves 50% of the recommended fertilizer. Therefore, micro-dosing application of 30.75 kg N ha−1 and 34.5 kg P2O5 ha−1 for Aybra-Sekota and of 20.5 kg N ha−1 and 23 kg P2O5 ha−1 for Shumshiha-Lasta Lalibela (N applied in three splits) are recommended for sorghum production.