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Organic additions help improve soil biophysical qualities, but they are insufficient to supply nutrient demand and could result in unintentional nutrient immobilization in soils, particularly soils with low fertility status. A 16-week laboratory incubation study was conducted to determine how the method of application of compost and inorganic fertilizers influence microbial respiration, nitrogen (N), and phosphorus (P) mineralization. Topsoil (500 g, 0–15 cm) was amended with compost (0, 5, and 10 g kg−1) and either inorganic N (50 kg N ha−1) or P (30 kg P ha−1). Two soil amendment strategies, applying compost and inorganic fertilizer separately to opposite sides of the soil using a divider and mixing them evenly throughout the soil, were compared for their effects on microbial activity and nutrient mineralization. The cumulative amounts of carbon dioxide (CO2) evolved were measured fortnightly using the static CO2 absorption method and inorganic N and P mineralization. N mineralization was unaffected by the method of compost and inorganic fertilizer application (p >.05), while at the end of day 42, available P in separate applications of compost and mineral N fertilizers was 33% greater than combined applications. Compost and inorganic P fertilizer had favorable N priming effects, but compost and inorganic N had negative effects. The different N priming effects of compost and inorganic N and P fertilizers may be attributable to microbial nutrient demand. The data suggest that composting with conventional fertilizers may change microbial nutrient demand and crop nutrient availability. [ABSTRACT FROM AUTHOR]

The availability of phosphorus (P) in ultisol acid soils presents a significant challenge due to its attachment to aluminum (Al) or iron (Fe) compounds. A potential solution to address this issue is the utilization of phosphate solubilizing bacteria (PSB). Therefore, this study aimed to analyze the potential of PSB originating from upland rice cultivation on ultisol soils. The bacterial isolates were obtained from soil samples taken from the rhizosphere area and root tissue of upland rice plants cultivated in Payabenua and Saing Villages, Bangka Regency. The pathogenicity testing encompassed hypersensitivity and hemolysis tests, while the P solubilization included the evaluation of the phosphate solubilizing index (PSI) and P dissolution. Subsequently, the selected isolates were subjected to phosphatase enzyme and organic acid content assessment. The results showed a total of 120 isolates, predominantly distributed in the Payabenua area and primarily consisting of endophytic bacteria. Among the six selected isolates, genus Burkholderia dominated four isolates, while the remaining isolates belonged to genus Serratia. Furthermore, in Burkholderia vietnamiensis, the solubility value of P in AlPO4 and Ca3(PO4)2 liquid media exhibited a range of 0.0013 to 0.0344% and 0.0008 to 0.1842%, respectively. [ABSTRACT FROM AUTHOR]

Ultisols in Indonesia have the potential for agricultural development, but the soils have low pH and nutrient contents that hinder plant growth and yield. Using animal manure can be an alternative to improve soil productivity and crop yields. This study aimed to examine the effects of animal manure on the chemical properties of Ultisol, yield, and secondary metabolic of Zingiber montanum. The treatments tested were combinations of types of manure (cow and chicken manure) and manure application levels, namely P0 (control), P1 (cow manure 20 t/ha), P2 (cow manure 40 t/ha), P3 (cow manure 60 t/ha), P4 (chicken manure 20 t/ha), P5 (chicken manure 40 t/ha), and P6 (chicken manure 60 t/ha). The results showed that the application of chicken manure of 60 t/ha increased N and P contents of the soil, and the application of cow manure of 60 t/ha increased soil cation exchange capacity. The application of cow manure of 60 t/ha gave the highest plant height, the number of leaves, and the number of at 18 weeks after planting, while the application of chicken manure dose of 60 t/ha produced the longest plant roots. The highest fresh and dry rhizome weight was observed for the 60 t/ha cow manure treatment. The highest secondary metabolic levels in each parameter were found in dry rhizomes (phenolic, flavonoid, and tannin) and fresh rhizomes (phenolic and flavonoid), with the highest tannin compound in the treatment of 40 t chicken manure/ha. The application of chicken manure at a dose of 60 t/ha resulted in a strong antioxidant yield in fresh and dry rhizomes.

Soil aggregates play a crucial role as carriers for storing and cycling soil phosphorus (P). Changes in the composition of soil aggregates (2–0.25, 0.25–0.05, 0.05–0.01, 0.01–0.005 mm, <0.005 mm) due to the long-term fertilization directly impact the P adsorption-desorption behavior of soil aggregate—associated P. This study aimed to investigate the effects of applying rice straw (RS) or pig manure (PM) in combination with NPK fertilizers on soil total P (TP) and Bray-P across all soil aggregates, as well as the adsorption capacity and release potential of aggregate-associated P. PM application significantly increased TP content by 90.7 to 175.1% and Bray-P content by 480.7 to 1009.9% in all aggregates, while RS application had no significant impact compared to NPK fertilizers alone application (CK). As the aggregate-associated P content increased, the P sorption capacity of all aggregates initially increased rapidly and then reached a plateau. PM application resulted in the lowest P adsorption capacity and the highest P release potential of all soil aggregates; among all soil aggregates, <0.005 mm aggregates exhibited the highest P retention capacity and the lowest P desorption ratio. Furthermore, regardless of aggregate size, correlation analyses indicated that free iron-aluminum oxides were the primary factors influencing both P sorption capacity and P release potential of soil aggregates in Ultisol. [ABSTRACT FROM AUTHOR]

Ultisols in Indonesia have the potential for agricultural development, but the soils have low pH and nutrient contents that hinder plant growth and yield. Using animal manure can be an alternative to improve soil productivity and crop yields. This study aimed to examine the effects of animal manure on the chemical properties of Ultisol, yield, and secondary metabolic of Zingiber montanum. The treatments tested were combinations of types of manure (cow and chicken manure) and manure application levels, namely P0 (control), P1 (cow manure 20 t/ha), P2 (cow manure 40 t/ha), P3 (cow manure 60 t/ha), P4 (chicken manure 20 t/ha), P5 (chicken manure 40 t/ha), and P6 (chicken manure 60 t/ha). The results showed that the application of chicken manure of 60 t/ha increased N and P contents of the soil, and the application of cow manure of 60 t/ha increased soil cation exchange capacity. The application of cow manure of 60 t/ha gave the highest plant height, the number of leaves, and the number of at 18 weeks after planting, while the application of chicken manure dose of 60 t/ha produced the longest plant roots. The highest fresh and dry rhizome weight was observed for the 60 t/ha cow manure treatment. The highest secondary metabolic levels in each parameter were found in dry rhizomes (phenolic, flavonoid, and tannin) and fresh rhizomes (phenolic and flavonoid), with the highest tannin compound in the treatment of 40 t chicken manure/ha. The application of chicken manure at a dose of 60 t/ha resulted in a strong antioxidant yield in fresh and dry rhizomes. [ABSTRACT FROM AUTHOR]

Fly ash is the residue of coal combustion that can potentially be an ameliorant. Unfortunately, its use is limited by government regulations that are classified as hazardous and toxic materials. This study examines the effectiveness of fly ash and cow manure as an ameliorant for Ultisols. The experiment was carried out by two factors, i.e., the dose of fly ash, namely 0, 50, 100, and 150 t/ha, and the quantity of cow manure, i.e., 10, 20, and 30 t/ha. The results show that fly ash and cow manure could be ameliorants for low-pH soils such as Ultisols. The suitable dose of fly ash and cow manure as ameliorants in this study are 50 t/ha and 20 t/ha, respectively. Increasing the amount of fly ash caused a decrease in the growth of water spinach, plant height, number of leaves, fresh plant weight, root length, and dry weight of the root. In addition, fly ash increased pH 6.66-7.30, total P 31.74-52.21 mg/100 g, and total K 16.19-25.75 mg/100 g.

Methods of soil and water conservation in tropical wetlands have been carried out is using chemicals to increase the stability of soil aggregates and water-holding capacity. The experiment aims to improve soil stability using Polyacrylamide (PAM) and Super Absorbent Polymer (SAP) materials. Experiment was carried out in R&D Dept. PT. Great Giant Pineapple (PT. GGP), Lampung. The treatment was to mix ingredients into the water with variations the ratio of ingredients (g): water (ml), among others, 1:100, 1:200, 1:300, and 1:400. Next, the SAP/PAM material is mixed into 100 g of soil with a dose of 0 g, 4 g, 8.5 g and 10 g of SAP. After the soil was mixed with the SAP, take as much as 15 g and place it in a pot containing 1 kg of soil. Results experiment show the SAP is a polymer capable of increasing water availability in ultisols and sand used in the experiment and can increase the water content by 18% if compared control. Meanwhile, PAM is a more dominant polymer in its function as an aggregate adhesive instead of a water binder. Super Absorbent Polymer (SAP) and Polyacrylamide (PAM) can chemically function as chemicals for soil conservation.

Copyright of Revista IRRIGA - Brazilian Journal of Irrigation & Drainage is the property of Revista IRRIGA (Brazilian Journal of Irrigation & Drainage) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agricultural Sciences, Belgrade is the property of University of Belgrade, Faculty of Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Indonesia has a wide area of acid-dry land with potential food crops, especially soybeans. The study was conducted to determine the effect of arbuscular mycorrhizal fungi (AMF) as seed coat of soybean on ultisol, applied with various doses of lime. The study was conducted in Ultisols in Kuranji Village, Kuranji District, Padang City, West Sumatra, Indonesia. The experiment was arranged in a split-plot design. The main plot was the dose of CaCO3 lime with two levels, namely 0 (without lime) and lime equivalent to 2 x Al-dd. Subplots were the application of seed coat in five ratios of AMF inoculant: former soybean planting soil, consisting of 0:4, 1:4, 2:4, 3:4, and 4:4. Each treatment was replicated three times. Data were analyzed for variance and the least significant difference (LSD) test with a significance level of 5%. The results showed that applying lime could increase P uptake in soybean plants by 25.58%. The highest soybean yield was 2.046 tons ha-1, yielded from seed coat treatment with a ratio of 2:4 without lime and the lime treatment equivalent to 2xAl-dd without seed coat.

A field experiment was conducted to assess the growth and yield of watermelon Citrullus lanatus [(Thunb.) Matsum. & Nakai] under acidic soil conditions in Calabar, Cross River State, Nigeria. The experiment was a 3 × 3 factorial experiment laid in a randomized complete block design (RCBD) with three replications. The factors studied were varieties (Heracles F1, Kaolack and Sugar Baby), lime rates (0 t ha-1 , 2.7 t ha-1 and 5.7 t ha-1 ), and their interactions on watermelon growth and yield traits. Heracles F1 and Kaolack outperformed Sugar Baby (p ≤ 0.05) regarding growth and yield traits. Lime rates of 2.7 t ha-1 and 5.7 t ha-1 increased the initial soil pH range (4.6-4.9) by 21.74% (5.4-5.8) and 43.48% (6.4-6.7), respectively. These rates improved the soil pH to a range suitable for watermelon cultivation in the study area. Vine length, number of leaves, transverse and longitudinal sections of the fruits and sugar content of the fruits had ≥ 50% heritability, a useful index in the selection of choice growth and yield traits in watermelon. Overall, GAM was greater than GA for each of the traits except for the total number of seeds per fruit. Multi-location studies are recommended to give further insights to this pilot study.

Rorippa indica L. Hiern is a local vegetable that is widely consumed by Dayak’s tribe in Central Kalimantan, Indonesia. It is mostly traditionally cultivated without fertilizers, resulting in low productivity. The research aimed to investigate the effect of fertilizers and soil type on the growth characteristics and N uptake of R. indica. The experiment was arranged in a factorial completely randomized design consisting of two factors with four replications. The first factor was fertilizer application (control, 20 t ha-1 of chicken manure, and 600 kg ha-1 of NPK), and the second was soil type (peat and Ultisol). The results revealed that the interaction of fertilizers and soil type gave a non-significant effect on all variables observed, except N uptake. The application of NPK increased the plant height and number of leaves significantly. Compared to control, the increment was 112.50% and 130.32%, respectively, and chicken manure application increased the dry weight (327.87%), N total (310.16%), and N uptake of plants by 478% in peat soil and 228% in Ultisol. This finding concludes that 20 t ha-1 of chicken manure can be applied to increase the productivity of R. indica.

Este estudio investigó el efecto de dos prácticas de labranza sobre el rendimiento y el crecimiento del maíz, y propiedades seleccionadas del suelo de un Ultisol del estado de Osun en Nigeria. Esto tuvo como objetivo seleccionar una práctica de labranza adecuada para el crecimiento de los cultivos y el mantenimiento del suelo. El estudio se dividió en dos parcelas experimentales durante la temporada de cultivo temprana y tardía en 2014. La primera parcela se desbrozó manualmente para tener labranza cero, mientras que la segunda parcela se aró dos veces y se rastrilló una vez para labranza convencional. Cada parcela tenía tres bloques (23.0 m x 2.5 m) con un callejón de 1.0 m entre bloques y 1.0 m dentro de las parcelas. Tres semillas del cultivo de prueba se colocaron a una distancia de 75 cm x 50 cm por montículo y cada parcela se desyerbó manualmente a intervalos de dos semanas hasta la cosecha. Las propiedades físicas y químicas del suelo seleccionadas y los parámetros de crecimiento de las plantas se recolectaron y determinaron utilizando el método estándar después de cada temporada de cultivo. Al final del experimento, tuvo los valores más altos de altura de planta y suelo en comparación con la labranza convencional. La labranza cero también tuvo valores químicos del suelo más altos en comparación con la labranza convencional. El rendimiento de grano mostró una diferencia significativa entre las prácticas de labranza. La labranza cero tuvo un mayor rendimiento (1.71 t/ha) en comparación con la labranza convencional (0.97 t/ha). El estudio concluyó que la labranza cero era una mejor alternativa para el crecimiento de los cultivos y el mantenimiento del suelo de un Ultisol.

Soils in subtropical and tropical regions are extremely fragile to perturbations due to their sandy texture, acid nature, low soil organic carbon (SOC) and low cation exchange capacity. In Paraguay, deforestation and subsequent cultivation affect 60% of the land. Certain conservation practices were carried out in the 1970s in response to the important degree of degradation caused by the soil degradative processes. Although the management of crop soils is still very intensive, to date there is no data on how the practices are affecting the sustainability of the system. The objective of this study was to evaluate the chemical and physical properties of three subtropical soils (Ultisol, Alfisol and Oxisol) under different agricultural systems and types of management, aimed at conservation, in the Eastern Region of Paraguay. The agricultural systems differ in the main crop (soybean or maize) and rotation crop (oat, turnip, crotalaria, lupins, maize). The soil properties were compared with those in disturbed natural forests and eucalypt plantations established on former agricultural land. The physical and chemical properties of the soil were determined in the 0 to 40 cm layer. The soils in the disturbed natural forest systems were less acidic and contained more Ca, Mg and K than the cultivated soils. Relative to the seminatural forests, the cultivated soils contained 20 to 40% less SOC and had lower macronutrient reserves and higher bulk density (up to 1.45 g cm−3). The SOC was higher in the agricultural systems with oats sown as a rotation crop in winter. By contrast, the N content was higher in systems with lupins or turnips grown in winter. Even when managed using conservation practices (direct sowing, retention of harvest residues, green manure), the soils in the agricultural systems under study displayed signs of physical and chemical degradation. The findings show that these conservation practices are not sufficient to correct the impact of intensive agricultural management. [ABSTRACT FROM AUTHOR]

Superior upland rice varieties can be obtained through the plant breeding process. Upland rice lines that are carried out from crossing have different potentials. The research aims to determine upland rice promising lines with high yields in acid-dry land. The study is conducted on Ultisol soil. The first season is in 2019 for F6 lines, and the second is in 2021 for F7 lines. The experimental methods use factorial Randomized Block Design (RBD). The treatment at the preliminary yield test use 5 lines 4 varieties, and 1 landrace. The advanced yield test uses 5 F7 lines (selected from F7 lines) and 5 types. Analysis data use ANOVA and LSI test. The result shows that lines GH8 and GH10 have the highest yields on acid-dry soils during two planting seasons. The GH10 line has a 7.20-9.53 kg/plot yield, and the GH8 line has a 5.22-6.260 kg/plot. The highest yield potential was the GH10 line of 3.69-4.77 t/ha, more increased than Balok, Banyuasin, Danau Gaung, Inpago 8, and PBM-UBB1 varieties. GH10 and GH8 lines are recommended as candidates for new superior varieties of upland rice that are adaptive to acid-dry soils. [ABSTRACT FROM AUTHOR]

Penelitian yang dilakukan bertujuan untuk melihat pengaruh dari pupuk kompos terhadap pertumbuhan dan hasil rumput Kumpai (Hymenachne amplexicaulis (Rudge) Nees.) di tanah ultisol. Penelitian ini dilaksanakan selama ± 4 bulan, pengomposan dan penanaman laksanakan di Laboraturium Budidaya Ternak dan Hijauan, untuk analisis bahan kering di Laboratorium Analisis Fakultas Peternakan Universitas Jambi. Penelitian ini menggunakan Rancangan Acak Lengkap (RAL) yang terdiri dari 4 perlakuan serta 5 ulangan. Perlakuan pupuk kompos terdiri dari A0 = 0,00 g/pot atau setara dengan 0,00 ton/ha, A1 = 50 g/pot atau setara dengan 10 ton/ha, A2 = 100 g/pot atau setara dengan 20 ton/ha, dan A3 = 150 g/pot atau setara dengan 30 ton/ha. Untuk bahan penanaman digunakan TSP (45% P2O5) dengan dosis 200 Kg P2O5/ha setara 2,22 g TSP/pot, KCl (60% K2O) dengan dosis 200 Kg K2O/ha setara 1,66 g KCl/pot, CO(NH2)2 (46% N) dengan dosis 200 Kg N/ha setara 2,17 g urea/pot, dan kapur dolomit 2 ton/ha setara 10 g/pot. Peubah yang diamati yaitu tinggi tanaman, jumlah anakan, hasil kumulatif bahan kering hijauan, dan berat kering akar. Hasil analisis sidik ragam menunjukkan bahwa pemberian pupuk kompos berpengaruh sangat nyata (p

Soil organic matter mineralization changed by land-use types is still not clearly understood. In this study, soils from typical land-use types including adjacent plantations of bamboo (Bam), camphor (Cam), and tea (Tea) were chosen to systematically investigate the role of organic carbon components and microbial community compositions in the organic matter mineralization in Ultisol. The mineralization of organic matter followed the sequence Bam < Cam < Tea. The higher carbon contents of labile pools were in the Cam and the Tea than that in the Bam. The carbon content of dissolved organic matter (DOM) showed the order Bam < Cam < Tea, whereas the complexity of chemical structure in DOM followed the opposite trend. The land-use types significant shifted the bacterial and fungal communities, and the relative abundances of bacterial or fungal phyla of Actinobacteria, Acidobacteria, Firmicutes, and Basidiomycota were significantly different among the land-use types. The multivariate regression tree results showed that the total organic carbon and/or the C/N ratio were dominant factors in influencing the bacterial and fungal communities. Moreover, the redundancy analysis results demonstrated that the communities of bacteria and fungi in Bam, Cam, and Tea were tightly linked to the C/N ratio, the pH and the labile pool I carbon, and the DOM, respectively. The Pearson's correlation results revealed that the mineralization of organic matter was significantly correlated with the organic carbon components, but generally not the microbial community compositions, which implied that the organic carbon components were perhaps the major determinant in controlling the organic matter mineralization in Ultisol. [ABSTRACT FROM AUTHOR]

This research aimed to utilize Ultisol soil in increasing the growth and production of corn by improving the constraints on Ultisol soil, one of which is low pH and low organic matter. A compost for oil palm empty fruit bunches with cellulolytic bacteria could be used to solve the problem of Ultisol soil. This research was carried out in the experimental garden of the Faculty of Agriculture, Riau University from November 2020 to March 2021. This research was conducted experimentally used completely randomized design with 4 replications. The procedure for providing oil palm empty fruit bunches compost with cellulolytic bacteria is as follows: T0 = 0 ton ha1, T1 = 5 ton ha-1, T2 = 10 ton ha-1, T3 = 15 ton ha-1, T4 = 20 ton ha-1 . The results of this research indicated that the application of 20 ton ha-1 could give a significant effect on each parameter such as plant height, male flower appearance, female flower appearance and plant dry weight. Based on the results of the research, it is recommended to use oil palm empty fruit bunches compost with cellulolytic bacteria at a dose of 20 ton ha-1 to get optimal results. [ABSTRACT FROM AUTHOR]

The deep regolith of the southeastern United States has undergone rapid erosion in the last two centuries due to intensive agricultural practices, which has altered the landscape and its inherent fertility. Parent material, landscape position, and land use are important factors in controlling the mineral and elemental composition of soil profiles. Independent quantitative X-ray diffraction (QXRD) and whole-rock chemical analysis of eight weathering profiles agreed well and allow mineral reaction pathways to be constrained as particles are conveyed in the subsurface. QXRD analysis of saprolite, argillic, and soil A-horizons in the profiles highlights the imprint of bedrock on the regolith, which includes Neoproterozoic meta-tonalitic to meta-granodioritic and Paleozoic meta-granitic to biotite- and amphibolite-gneissic lithologies. Also, aeolian input slightly influenced A-horizon composition. The clay mineral assemblage is dominated by kaolinite, but profiles differ in the amount of interstratified clay minerals, halloysite, hematite, goethite, and gibbsite. Rare-earth element totals vary between 30 and 1048 ppm and are generally correlated positively with clay and clay mineral content. Eu and Ce anomalies reflect parent rocks and subsequent hydrolysis and redox history, with trends depending upon landscape position and clay content in the weathering profile. Weathering profiles on a high-order interfluve and those that were actively cultivated have thick argillic horizons (as defined by clay mineral abundance) and are depleted in alkali and alkaline-earth elements. Profiles proximally developed on old-field pine and never-cultivated hardwood forest land do not show large differences in mineral composition trends, whereas profiles on old-field sites with ongoing cultivation exhibit assemblages enriched in clay minerals and (oxyhydr)oxides. Old-field pine sites that were historically eroded by previous cultivation tend to have shallower and thinner argillic horizons, which may well impact critical-zone processes involving gas and water fluxes. This study highlights that mineral compositions of deep regolith, saprolite, and shallow soil horizons are dependent on local geomorphology (i.e. watershed- and hillshed-orders). Quantifying soil and regolith compositional trends across the landscape is a prerequisite for determining rates of chemical and physical erosion on human and geologic time scales. [ABSTRACT FROM AUTHOR]

Coal fly ash (CFA) is a coal-burning by-product containing macro and micronutrients, and it is the potential material for improving available P in Ultisols. Phosphate-solubilizing bacteria (PSB) play a role in phosphorus solubilization. This study aimed at elucidating the potential use of phosphate-solubilizing bacteria to optimize the use of coal fly ash for increasing soil available P. This study was conducted in two stages, namely isolation of indigenous PSB from an Ultisol and application of the PSB and CFA to improve soil available P. Five indigenous PSB isolated from the soil had the ability to dissolve phosphate. Isolate B5 could dissolve 9.89 ppm P and had a 99.57% closeness to Pseudomonas stutzeri. The application of 20 and 40 t CFA ha-1 increased the soil pH by 4.2% and 7.2%, respectively. Increasing the dose of CFA decreased the content of available P by 50.6%. However, the combination of PSB and 20 t CFA ha-1 increased soil available P, plant growth, plant dry biomass, and P-uptake by plant.

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Abstract Background Despite the crucial role of nitrogen (N) availability in carbon (C) cycling in terrestrial ecosystems, soil organic C (SOC) mineralization in different sizes of soil aggregates under various land use types and their responses to N addition is not well understood. To investigate the responses of soil C mineralization in different sized aggregates and land use types to N addition, an incubation experiment was conducted with three aggregate-size classes (2000, 250, and 53 μm) and two land use types (a Chinese fir plantation and a paddy land). Results Cumulative C mineralization of the

Abstract Deterioration in soil–water environment severely contributed by heavy metal bioavailability and mobility on soil surface and sub-surface due to irrational increase in wastewater discharge and agrochemical activities. Therefore, the feasibility of adsorption characteristics of the soil is paramount in curbing the problem of micropollutant contamination in the farming vicinity. Soil from a farming site in a populated area in Enugu, Nigeria was collected and tested to measure the lead and cadmium contents using atomic absorption spectrophotometer (AAS). The adsorption potency of the ultisol soil was estimated for identifiable physicochemical properties by standard technique. The mean activity concentration of Pb2+ and Cd2+ was 15.68 mg/kg and 3.01 mg/kg. The pH, temperature, metal concentration and contact time adsorptive effect on the Pb2+ and Cd2+ uptake was evaluated by batch adsorption technique. The Langmuir, Freundlich and Temkin models were fitted into equilibrium adsorption data and the calculated results depict a better and satisfactory correlation for Langmuir with higher linear regression coefficients (Pb2+, 0.935 and Cd2+, 0.971). On the basis of sorption capacity mechanism of the soil, pseudo-second-order model best described the kinetics of both metal ions retention process. The results of the present study indicated that the soil being a low cost-effective adsorbent can be utilized to minimize the environmental risk impact of these metal ions.

Rice is the primary food commodity in Indonesia. To increase the rice production, urea fertilizer has been excessively used, specifically on marginal land. However, it has no desired effect on the plant’s Nitrogen uptake due to volatilization. Previous studies suggest the use of zeolite to be mixed with urea to reduce the volatilization rate. This study aimed to determine the effect of six NP-SR (Nitrogen Phosphorus Slow Release) fertilizer compositions (without NP-SR; 20.69-0; 19.7-5; 17.27-10; 15.9-15; and 18.94-20) on soil chemical properties, nitrogen efficiency, and paddy rice yield on Ultisols at three waterlogging levels (0.5 cm, 3 cm, and 5 cm). The study was an experiment arranged in a Randomized Complete Block Design (RCBD) consisting of two factors, which were waterlogging levels and NP-SR fertilizer compositions. The results showed that waterlogging treatments significantly affected soil chemical properties in the initial vegetative and harvest phases. It can be concluded that the treatment of flooding (up to 3 cm) and fertilizer (NP-SR of 15.90-15) application could significantly reduce the volatilization rate, increase the efficiency of N fertilizer, and increase rice yield.

Temporal changes in soil development were assessed on fluvial terraces of the Little River in the upper Coastal Plain of North Carolina. We examined five profiles from each of six surfaces spanning about 100,000 years. Soil-age relationships were evaluated with inter-surface clay mineral comparisons and regression of chemical properties versus previously reported optically-stimulated luminescence ages using the most developed subsoil horizon per profile. Bases to alumina (Bases/Al2O3) ratios have negative correlations with age, whereas dithionite-Fe (FeD) concentrations are positively correlated with time and differentiate floodplain (<200 yr BP) from terrace (≥10 ± 2 ka) soils and T4 pedons (75 ± 10 ka) from younger (T1-T3b, 10 ± 2–55 ± 15 ka) and older (T5b, 94 ± 16 ka) profiles. Entisols develop into Ultisols with exponentially decreasing Bases/Al2O3 ratios, reflecting rapid weatherable mineral depletion and alumina enrichment during argillic horizon development in the first 13–21 kyr of pedogenesis. Increasing FeD represents transformation and illuviation of free Fe inherited from parent sediments. Within ~80–110 kyr, a mixed clay mineral assemblage becomes dominated by kaolinite and gibbsite. Argillic horizons form by illuviation, secondary mineral transformations, and potentially, a bioturbation-translocation mechanism, in which clays distributed within generally sandy deposits are transported to surface horizons by ants and termites and later illuviated to subsoils. T5b profiles have FeD concentrations similar to, and gibbsite abundances greater than, those of pedons on 0.6–1.6 Ma terraces along Coastal Plain rivers that also drain the Appalachian Piedmont. This is likely because the greater permeability and lower weatherable mineral contents of sandy, Coastal Plain-sourced Little River alluvium favor more rapid weathering, gibbsite formation, and Fe translocation than the finer-grained, mineralogically mixed sediments of Piedmont-draining rivers. Therefore, recognizing provenance-related textural and mineralogical distinctions is crucial for evaluating regional chronosequences. [ABSTRACT FROM AUTHOR]

Bawang dayak is a medicinal plant and can be grown as an economical crop with great potential value. Its contains secondary metabolites with biological activities that are important for human health. The main problem related with the production of bawang dayak is the standard of cultivation. The goal of the experiment was to study the effects of organic fertilizers and growing media on the growth and yield of bawang dayak. The polybag experiment was performed with two factors, namely soil type and organic fertilizer by Factorial Completely Randomized Design and located in the greenhouse of University of Palangka Raya. The treatments were chicken manure, oil palm empty-fruit-bunch compost (OPEFBC), and NASA granule as organic fertilizers, while Histosol and Ultisol served as growing media treatment. The results showed that OPEFBC gave the highest in Ultisol and chicken manure in Histosol to improve plant height. The highest number of tubers were developed in Ultisol. Chicken manure improved P and Fe bulbs tissue whereas the content of N and K bulbs grown in Ultisol was higher than those in Histosol.

Soil chiseling conducted only in the planting row is a minimal-disturbance soil management practice used for soil preparation in sugarcane plantations. However, the impacts of this practice on soil physical quality need to be evaluated through agricultural experimentation. The objective of this study was to evaluate the physical quality of an Ultisol submitted to chiseling as part of sugarcane management. The treatments consisted of soil chiseling only in the planting row (CPR) and chiseling in the total area of the soil (CTA). After soil preparation, the planting rows that were submitted to chiseling had better soil physical quality than did the area between the rows that did not receive chiseling in site preparation due to greater pore volume and lower PR and BD. However, the beneficial effect of chiseling did not persist due to subsequent soil reconsolidation, and disappeared soon after the planting of sugarcane, and remained this way up to the post-harvest period wherein the areas within (CPR) and between (CTA) the planting rows had equal soil physical quality. Because of this, the yield of stalks between the two treatments were similar, with an average yield of 110 t ha−1. [ABSTRACT FROM AUTHOR]

The need for cheap and affordable alternate sources of plant nutrient inputs to boost the nutrient level of degraded arable farmlands has been a major concern for soil scientists. In 2018, a field study was carried out under rain-fed conditions to evaluate the effect of palm waste biochar (PWB), poultry litter biochar (PLB) and inorganic fertilizer on the properties of soil, N and P use efficiency on a sandy Ultisol. The treatments consisted of T1 (control), T2 (625 kg ha-1 NPK fertilizer), T3 (10 t ha-1 PWB + 625 kg ha-1 NPK fertilizer), T4 (10 t ha-1 PLB + 625 kg ha-1 NPK fertilizer), T5 (5 t ha-1 PWB + 5 t ha-1 PLB + 625 kg ha-1 NPK fertilizer) and T6 (10 t ha-1 PWB+10 t ha-1 PLB + 625 kg ha-1 NPK fertilizer). These treatments were arranged in a randomized complete block design and replicated three times. Data were analysed using Analysis of Variance (ANOVA) and significant effects among treatment means were determined using Fishers Least Significant Difference (F-LSD) at a 5% probability level. Results showed that biochar application significantly (p = 0.05) reduced soil bulk density by 9.9%, increased soil organic matter by 28.4%, total exchangeable bases by 34.8% and raised soil pH by 19.2%. The number of leaves, plant height and leaf area of maize were significantly higher in the amended plots than that of the control plots after six weeks of planting. Plots amended with 10 t ha-1 PLB+625kg ha-1 NPK fertilizer had the highest grain and fresh cob yield of 3.08 t ha-1 and 7.53 t ha-1, respectively, while the least values were obtained in the control plots (2.18t ha-1 and 4.03 t ha-1, respectively). The highest values of nitrogen uptake (70.84 kg ha-1), physiological efficiency of (27.47 kg ha-1), phosphorus uptake (78.54 kg ha-1), phosphorus use efficiency (80.14%), agronomic efficiency of N (9.6 kg ha-1), agronomic efficiencies of P(22.02 kg ha-1), partial factor productivity of N (32.85 kg ha-1) and P (75.34 kg ha-1) as well as N physiological efficiency (30.6 kg ha-1) were obtained in plots amended with 10 t/ha PLB + 625 kg ha-1 NPK fertilizer. Therefore, application of 10 t ha-1 PLB + 625 kg ha-1 NPK fertilizer is recommended for improved N and P use efficiencies, N and P uptakes, yield performance of maize and improvement in the soil properties of a degraded acidic soil.

Biochar is an organic material instantly made by burning wood into charcoal by pyrolysis, which can meet the high demand for an organic material that cannot be available in a short time. The study aimed to determine the effect of biochar and Chromolaena odorata liquid fertilizer (CLF) enriched with Sodium bicarbonate on soil pH and Muskmelon (Cucumis melo L.) productivity. The research was conducted from December to February 2019 at the field station of Tamansiswa University, Padang. The study was carried out in a factorial experiment with 2 treatment factors arranged in a Completely Randomized Design, consisting of three replications within treatments. The data obtained were analyzed using the F test at 5%, followed by the Least Significant Difference (LSD) test at 5%. The results showed that there was an interaction effect of Biochar and CLF application on reducing the soil pH. Among all treatments, the application of 2 t.Ha-1 biochar combined with 50 ml.L-1 CLF + 0 g.L-1 sodium bicarbonate resulted in the highest growth rate and yield of muskmelon in Ultisols soil.

Soybean is an agricultural product that has a good nutritional value, especially Protein content. This study aims to find superior varieties that have a wide adaptation to the sour soil especially in Ultisol soils. The study was conducted in Gulo Village, Darul Hasanah Sub-District, Southeast Aceh Regency, Aceh Province, from May to September 2019. The study used a non factorial randomized block design (RBD), with 4 treatment varieties (V) levels that were repeated as many as 4 replications; namely V1: Anjasmoro Varieties, V2: Dena Varieties, V3: Deja Varieties 1, V4: Detaptive Varieties 1, Variance analysis test results showed that the plant height was 1 WAP, Age 2 WAP, Age 3 WAP, Age 4 WAP, Age 5 WAP , and Age 6 WAP had no significant effect. However the highest yield on 1 WAP was found in variety V4 (10.40) in the second test and the lowest was in the first test. V2 was second test. While the best number of segments and branches were produced by V3 treatment. The best results for the total number of pods, number of pods, total empty pods, number of sample plant seeds and weight of sample plant seeds were produced by treatment V3.

The experiment was conducted to examine the effects of indigenous mycorrhizae inoculation and cow manure doses on the growth and yield of oil palm (Elaeis guineensis) at production stages I. It was conducted at farmer plantation in Semabu Village Tebo Regency located at -1.473543, 102484062. This research was arranged in a randomized block design consisting of two factors. The first factor is inoculation of mycorrhizae isolates comprising two levels, i.e. without and with inoculation, and the second factor is the dose of cow manure comprising five levels, i.e. without cow manure, 25%, 50%, 75%, and 100% of the recommended dose of cow manure at Production Stages I (30 kg plant-1). The variables observed were plants girth, leaf midrib, number of bunches per plant, weight per bunch, weight of fresh fruit bunches per plant, and root infection. The results showed that there was interaction effect between inoculation of mycorrhizae and cow manure doses. The inoculation of mycorrhizae and cow manure at a dose of 50% of the recommended dose were able to increase oil palm growth and yield.

Soil organic matter mineralization changed by land-use types is still not clearly understood. In this study, soils from typical land-use types including adjacent plantations of bamboo (Bam), camphor (Cam), and tea (Tea) were chosen to systematically investigate the role of organic carbon components and microbial community compositions in the organic matter mineralization in Ultisol. The mineralization of organic matter followed the sequence Bam < Cam < Tea. The higher carbon contents of labile pools were in the Cam and the Tea than that in the Bam. The carbon content of dissolved organic matter (DOM) showed the order Bam < Cam < Tea, whereas the complexity of chemical structure in DOM followed the opposite trend. The land-use types significant shifted the bacterial and fungal communities, and the relative abundances of bacterial or fungal phyla of Actinobacteria, Acidobacteria, Firmicutes, and Basidiomycota were significantly different among the land-use types. The multivariate regression tree results showed that the total organic carbon and/or the C/N ratio were dominant factors in influencing the bacterial and fungal communities. Moreover, the redundancy analysis results demonstrated that the communities of bacteria and fungi in Bam, Cam, and Tea were tightly linked to the C/N ratio, the pH and the labile pool I carbon, and the DOM, respectively. The Pearson’s correlation results revealed that the mineralization of organic matter was significantly correlated with the organic carbon components, but generally not the microbial community compositions, which implied that the organic carbon components were perhaps the major determinant in controlling the organic matter mineralization in Ultisol.

Rice husk biochar and compost application are expected to improve soil chemical properties such as pH, organic carbon, and available P in Ultisol, which in turn improves crop growth and P uptake by plants. The purpose of this research was to analyze the effect of the combination of rice husk biochar and compost on the soil chemical properties (pH, organic carbon, and available P), maize growth, and P uptake by maize in an Ultisol. The research used a Randomized Block Design with six treatments (P0: control; P1: 4 t biochar ha-1; P2: 30 t compost ha-1; P3: 4 t biochar ha-1 and 30 t compost ha-1; P4: 8 t biochar ha-1 and 30 t compost ha-1; P5: 4 t biochar ha-1 and 60 t compost ha-1) and four replications. The result showed that the combination of 8 t rice husk biochar ha-1 and 30 t compost ha-1 showed a significant effect on increasing pH, organic carbon, and available P in an Ultisol, increasing the height of maize crops at 4 and 6 WAP (weeks after planting). However, it had no effect on the number of leaves and showed an effect on the increase in P uptake of maize crop.

Ultisol is one of the soils with limited physical characteristics. The water content is low, the permeability is not enough to pass water into the soil, and the organic-C content is classified as moderate. So that it affects the soil in storing low water, one solution to overcome the physical characteristics of is to provide organic matter into the soil. The purpose of this study was to determine the physical characteristics of Ultisol and to determine the effect of the combination of organic matter from cow dung and rice husk ash on the soil water holding capacity of ultisols on dry land. This study was conducted at the Laboratory of Wira Wacana Christian University, Sumba. This study used a completely randomized design with six treatments and four replications. Observation data were subjected to analysis of variance followed by LSD advanced test with a confidence level of 5%. The results showed that the application of organic matter on the soil significantly affected water content, field capacity, permeability, and C-organic. The application of organic matter can improve soil structure, not soil texture gave a very significant effect, and the treatment that had the best water content was 75% cow dung + 25% rice husk ash.

The maize crop is an important commodity other than rice in Indonesia. Maize production reached 30 million tons in 2018. Efforts that can be made to increase maize production on Ultisols in Indonesia is by the application of biochar rice husk and compost. Biochar that has a high affinity for nutrients does not experience decay in the soil for decades, while compost can improve soil chemical properties by increasing nutrient content. The purpose of this study was to analyze the effect of the application of a combination of rice husk biochar and compost on soil chemical properties, N uptake, and growth of maize on an Ultisol. This study was conducted with six treatments. The results showed that the application of a combination of rice husk biochar and compost had an effect on increasing the C-organic and N-total in soil, but it did not affect the C/N of the incubated soil. Application of a combination of 8 t rice husk biochar ha-1 and 30 compost ha-1 significantly improved plant height, dry weight, and N uptake of maize plants.

Deterioration in soil–water environment severely contributed by heavy metal bioavailability and mobility on soil surface and sub-surface due to irrational increase in wastewater discharge and agrochemical activities. Therefore, the feasibility of adsorption characteristics of the soil is paramount in curbing the problem of micropollutant contamination in the farming vicinity. Soil from a farming site in a populated area in Enugu, Nigeria was collected and tested to measure the lead and cadmium contents using atomic absorption spectrophotometer (AAS). The adsorption potency of the ultisol soil was estimated for identifiable physicochemical properties by standard technique. The mean activity concentration of Pb2+ and Cd2+ was 15.68 mg/kg and 3.01 mg/kg. The pH, temperature, metal concentration and contact time adsorptive effect on the Pb2+ and Cd2+ uptake was evaluated by batch adsorption technique. The Langmuir, Freundlich and Temkin models were fitted into equilibrium adsorption data and the calculated results depict a better and satisfactory correlation for Langmuir with higher linear regression coefficients (Pb2+, 0.935 and Cd2+, 0.971). On the basis of sorption capacity mechanism of the soil, pseudo-second-order model best described the kinetics of both metal ions retention process. The results of the present study indicated that the soil being a low cost-effective adsorbent can be utilized to minimize the environmental risk impact of these metal ions. [ABSTRACT FROM AUTHOR]

Ultisols have poor soil characteristics, yet biochar is one of the technologies that can be applied as a soil enhancer to improve the soil quality. Biochar has succeeded in improving soil quality, through improving soil physical, chemical, and biological properties. This research aimed to improve the quality of soil chemical properties and growth of maize plant, as well as to find a combination between biochar type and dosage of biochar that is able to improve the chemical properties of Ultisols and/or the growth of maize plant. This research was conducted at the Greenhouse and Soil Science Laboratory, Faculty of Agriculture, University of Lampung. This study used a randomized block design (RBD) arranged in factorial with 3 factors and 3 replications. The first factor was the soil layer (topsoil and subsoil), the second factor was the type of biochar (biochar of cocoa shell and biochar of oil palm shell), and the third factor was the biochar dosage (0, 10%, 20%, and 30% of 10 kg of oven dry weight soil). The results showed that (1) the application of biochar from the cocoa shell and oil palm shell on Ultisols improved some parts of soil chemical properties, namely CEC, organic C, and Kexc, (2) application of biochar from the cocoa shell and oil palm shell on Ultisols increased the plant height, the number of leaves, and the dry weight of maize, (3) application of biochar from the cocoa shell at a dosage of 20% was significantly improved CEC of Ultisols (4) application of biochar from the cocoa shell in top soil at a dosage of 30% significantly improved the soil organic C of Ultisol, (5) application of biochar from cacao shell at a dosage of 30% was significantly improved Kexc, (6) application of biochar from oil palm shell at a dosage of 10% significantly increased maize plant growth.

Low pH and phosphorus are among major soil chemical constraints to Biological Nitrogen Fixation (BNF) and soybean production in sub-Saharan Africa. A screenhouse pot experiment was conducted at Sokoine University of Agriculture- Morogoro Tanzania, to examine the ameliorating effect of liming to pH, phosphorus uptake, BNF and yield of soybean grown on an ultisol. The experiment was a 33 factorial laid out as a split plot with two replications. Source of nitrogen (inoculation, non-inoculation and applied inorganic nitrogen) was main plot factor, while the subplots received combinations of lime and phosphorus. The levels of lime used for the incubation experiment were 0, 5 and 10 ton ha-1 while those of P were 0, 50 and 100 kg*ha-1. A commercial inoculant-Legumefix, was used for inoculation. Results indicated that liming significantly (P

A study aimed at elucidating the utilization of coal fly ash and oil palm empty fruit bunch compost to improve soil phosphorus uptake and yield of maize grown on an Ultisol was carried out in a greenhouse. The treatments tested were a combination of four coal fly ash doses (0, 20, 40, and 80 t ha-1) and three doses of oil palm empty fruit bunch compost (0, 10, and 20 t ha-1). At 2, 4, 6 and 8 weeks after planting, plant height, leaf number and stem diameter were observed. At the time of harvest (10 weeks after planting), fresh and dry weights of cobs, roots, stem, leaves, and seeds, as well as P uptake on the plant tissues, were observed. The results showed that the application of coal fly ash and oil palm empty fruit bunch compost significantly increased P uptake, growth and yield of maize. The combination of 80 t coal fly ash ha-1 with 20 t oil palm empty fruit bunch compost ha-1 compost resulted in the highest P uptake, growth and yield of maize. Compared to the control treatment, the increase in P uptake by maize, the fresh cob weight, the dry cob weight, the biomass dry weight, and the dry seed weight were 303.23%, 285.39%, 364.91%, 329.59% and 1,591.70%, respectively.

Land circumstances on Seputih Mataram, Lampung included in dried area which is consist of Ultisols soil (soil taxonomy). Ultisol consist of H2O which has pH of less than 5.5. It will cause the amount of soil nutrient that absorbed is not optimal yet. This research aimed to know the influence of adding dolomite to the soil chemical content (pH number of H2O, KCl, content of total N, available P, exch-K, exch-Ca, exch-Mg, Organic-C, ratio C/N, exch-Al, exch-H, CEC), nutrient content on the leaf (such as N, P, K, Ca, Mg) and sugar cane physic. This research used Completely Randomized Design 2 factors with 3 blocks repetition. First factor was the dolomite doses in six contents: without the dolomite (K0), 500 kg/ha (K1), 1000 kg/ha (K2), 2000 kg/ha (K3), 4000 kg/ha (K4) and 6000 kg/ha (K5). The second factor (R) was the depth of dolomite placement, consist of: (R1) dolomite with 0-20 cm depth and (R2) dolomite with 20-40 cm depth. The observation used to know the soil chemical content, the leaf nutrients and the variables that used into the research. The observation results variant analyzed (ANOVA) in 5 % and continued with the Duncan’s Multiple Range Test (DMRT) in 5 % if the result showed the real differentiation. The result showed that the depth of dolomite was not real influence to the amount of Nitrogen (N), Phosphorus (P), Potassium (K), Calcium (Ca), and Magnesium (Mg) in leaf. Dolomite addition was real influence for Calcium (Ca) uptake in leaf, but it was not real influenced the leaf uptake. Dolomite addition was real influence in the leaf content and leaf Magnesium (Mg) uptake. 6000 kg/ha dolomite for physical soil characteristic ( pH H2O, pH KCL, C/N ratio, K, P, Ca, Mg,Exch-H), leaf nutrient ( N, K, Ca), Mg and Ca uptake on leaf also sugar cane tonnage per hectare showed the maximum result.

Bawang dayak is a medicinal plant and can be grown as an economical crop with great potential value. Its contains secondary metabolites with biological activities that are important for human health. The main problem related with the production of bawang dayak is the standard of cultivation. The goal of the experiment was to study the effects of organic fertilizers and growing media on the growth and yield of bawang dayak. The polybag experiment was performed with two factors, namely soil type and organic fertilizer by Factorial Completely Randomized Design and located in the greenhouse of University of Palangka Raya. The treatments were chicken manure, oil palm empty-fruit-bunch compost (OPEFBC), and NASA granule as organic fertilizers, while Histosol and Ultisol served as growing media treatment. The results showed that OPEFBC gave the highest in Ultisol and chicken manure in Histosol to improve plant height. The highest number of tubers were developed in Ultisol. Chicken manure improved P and Fe bulbs tissue whereas the content of N and K bulbs grown in Ultisol was higher than those in Histosol. [ABSTRACT FROM AUTHOR]

Ultisol is one type of soil that has a very wide distribution in Indonesia, but the use of this soil faces many obstacles. The main problem in ultisol utilization is the low availability of phosphorus (P) and the low absorption efficiency. Coal fly ash (CFA) is a material that can overcome these problems. The objective of this study was to examine the effect of Application CFA on several soil chemical properties (pH, exchangeable Al, exchangeable Ca and available P), plant growth, yield, and absorption efficiency of P fertilizer. This study used a completely randomized factorial design consisting of two factors. The first factor was CFA that consisted of three levels of treatment, namely: A0 = 0 t ha-1 or without CFA, A1 = 40 t CFA ha-1, A2 = 80 t CFA ha-1. The second factor was P fertilizer that consisted of four levels of treatment, namely: P0 = 0 kg ha-1, P1 = 30 kg P ha-1, P2 = 60 kg P ha-1 and P3 = 90 kg P ha-1. The results of the study showed that the application of 80 t CFA ha-1 increased the pH by 13.41%, reduced exchangeable Al by 59.53% and increased exchangeable by Ca 192.66% compared to control. The combination 80 t CFA ha-1 and 90 kg P ha-1 increased available P by 986.79% compared to control. The application of 80 t CFA ha-1 resulted in the highest total plant dry weight and total P uptake. The treatment resulted in total plant dry weight of 172.96 g and total P uptake of 187.62 mg plant-1, increased 62.39% and 100.21% respectively compared to the control. The application of 90 kg P fertilizer ha-1 resulted in the highest total dry weight of maize, and total P uptake, namely 167.49 g and 174.39 mg plant-1, respectively, which means that the total plant dry weight increased by 51.00% and the total uptake P increased 69.79% compared to control. The highest seed dry weight was obtained in the combination of 80 t CFA ha-1 and 90 kg P ha-1, namely 39.33 g, an increase of 715.53% compared to the control. The combination of 40 t CFA ha-1 and 30 kg P ha-1 resulted in the highest absorption efficiency of P fertilizer, namely 30.43%. This means that in this treatment, maize can absorb 30.43% of the applied P fertilizer.

Southeast Sulawesi is one of the provinces where agriculture is one of the fastest growing industries because most of the people are farmers. An obstacle encountered by farmers in Southeast Sulawesi is the lack of land for farming because most of the area is dominated by Ultisol. One way to overcome this problem is by using biofertilizers. This study aimed to isolate and characterize rhizobacteria from Ultisol as a material for making biofertilizers. The method used in sampling was purposive sampling. Soil samples taken were isolated for microorganisms and tested for hypersensitivity and then characterized based on the ability of nitrogen fixation, phosphate dissolving, and production of growth regulators. The test results and characterization of rhizobacteria selected 10 isolates from 92 isolated isolates, namely MN-06, MN-12, MN-21, KDI-09, KDI-11, KNW-02, KNW-05, KTM-07, KLK-04 , and KLK-09.

Background and aim: The diffusion of inorganic nitrogen (N) in soils is strongly affected by their physical characteristics and hydraulic gradients, which enable them to store and transport nutrients over time and space. The objective of this research was to use the microdialysis technique to continuously monitor the diffusive fluxes of inorganic N from the physical N store towards root surfaces in two volcanic soils after soil rewetting. Methods: Undisturbed soil samples were collected in metallic cylinders (230 cm3) at four depths (0–20, 20–40, 40–70, 70–100 cm) in two distinct volcanic soils (Andisol and Ultisol) that are used in agriculture. Diffusive N fluxes were determined during continuous drying and rewetting cycles (0 to 100 kPa) of intact undisturbed soil cores. Soil water content (SWC) at each water potential was calculated. Results and Conclusions: Diffusive NO3- fluxes increased significantly (p < 0.001) after rewetting in both soils: 16‐fold in the Andisol, from 32.7 ± 12.1 to 541.5 ± 306.5 nmol N cm−2 h−1 (34 to 62% SWC) and 66‐fold in the Ultisol, from 65.6 ± 25.8 to 4298.7 ± 1289.9 nmol N cm−2 h−1 (31 to 58% SWC) in the upper 20 cm of the soils. In addition, diffusive NO3- fluxes decreased with depth in both soils. We found that the residence time of available NO3- in these soils strongly depended upon actual SWC and thereby the functionality of the pores in the system. We propose that the ability of the porous system to transport water throughout the soil profile is a relevant parameter within N diffusion, since it allows us to estimate the increase or decrease of diffusive NO3- fluxes as a function of the soil water content during continuous drying and rewetting cycles. [ABSTRACT FROM AUTHOR]

Only a small portion of soil phosphorus (P) is available to plants on a short-term basis, and therefore, P taken up by crops in one growing season is small compared to total P (Pt) content of the soil. A group of soil microorganisms capable of transforming insoluble P into soluble and plant accessible forms. The objective of this study was to evaluate the changes in soil P-pools and P uptake by wheat crops as influenced by inoculation with Bacillus thuringiensis in two soils (Andisol and Ultisol), the experiment was conducted in pots under greenhouse conditions using a completely randomized design. Wheat plants were inoculated and re-inoculated at 20 and 46 days after sowing, respectively, with B. thuringiensis; and, plant sampling were performed after 46, 66 and 87 and soil at 87 days based on the Zadoks growth scale, and the soil was submitted by Hedley's P fractions. The inoculation with B. thuringiensis affected significantly some P organic P (Po) and inorganic P (Pi) fractions in both soils (Andisol and Ultisol), improved P uptake by wheat crop in (Ultisol) and decreased significantly in (Andisol). The positive effect was more consistent in Ultisol than in Andisol, this strain can be solubilized P fraction extracted with conc. HCl-Po and HCl 1 mol. [ABSTRACT FROM AUTHOR]

Liming increases soil fertility through improved soil conditions in acidic soils (Ultisols). This study aimed to determine the effect of limes [CaO; Ca(OH)2; CaCO3 and CaMg(CO3)2 ] on the chemical properties of Ultisols of Limau Manis Padang. Treatments tested in this study application of four types of lime, i.e. A = CaO; B = Ca(OH)2; C = CaCO3; dan D = CaMg(CO3)2. on an Ultisol. A control treatment with no application of lime was also included in this study. After incubation of the soil-lime mixtures for two weeks, the results of the study showed that liming using dolomite [CaMg(CO3)2] was more effective in improving the chemical properties of Ultisols, compared to other types of lime [CaO; Ca(OH)2; CaCO3]. The effect of dolomite on 1*exchangeable Al (1 me Ca 100 g-1) improved chemical properties of an Ultisol from Limau Manis Padang such as pH H2O by 0.35 unit, available P by 1.03 ppm, exchangeable Al by 0.91 cmolc kg-1; exchangeable H by 0.92 cmolc kg-1; CEC by10.49 cmolc kg-1; exchangeable K by 0.03 cmolc kg-1; exchangeable Ca by 0.44 cmolc kg-1 and exchangeable Mg by 1.34 cmol ckg-1, compared to control.