Soil Acidity

Growth inhibitory effects produced by the cypress, Cupressus lusitanica (Cupressaceae) in Bosque de La Hoja, Heredia, Costa Rica. In Costa Rica, Cupressus lusitanica is an introduced tree that may produce negative effects in the plants surrounding it. This study sought to compare light, soil humidity and acidity provided by cypress trees and the effect on the distribution and growth of pioneer and dicotyledonous plants around them in El Bosque de la Hoja, Heredia Province, Costa Rica. There were no differences in soil moisture and acidity at different distances from a cypress tree (acidity was similar to native forest). Monocotyledonous plants grow closer to cypress than dicotyledonous plants, particularly in parts that receive more light, suggesting an allelopathic effect that requires light as a catalyst.Although C. lusitanica could alter the light environment and the soil acidity and moisture, these negative effects could be countered with appropriate management.

Introduction

The increasing use of effluents for irrigation, particularly in regions facing water scarcity, poses a substantial threat to agricultural sustainability due to the high level of heavy metals. These metals can accumulate in soil and plants, posing risks to food safety and human health. To address this issue, researchers have explored various remediation techniques, including the use of layered double hydroxides (LDHs). The LDHs can potentially capture the heavy metals through multiple mechanisms. These include ion exchange, where positively charged layers attract and bind negatively charged metal ions. Surface complexation involves the formation of complexes between metal ions and hydroxyl groups on the LDH surface. The intercalation allows larger metal ions to enter the interlayer space and interact with anions. In addition, the precipitation of metal hydroxides within the interlayer space can further immobilize heavy metals. These mechanisms, acting synergistically, contribute to the remarkable adsorption capabilities of LDHs for heavy metal removal. However, the efficiency of LDHs can be further enhanced by incorporating biochar into their structure. Biochar, a carbonaceous material produced from the pyrolysis of biomass, possesses a high surface area and porosity, enhancing the adsorption capacity of LDHs. The combination of LDHs and biochar (BCLDH) creates a synergistic effect, resulting in a more efficient and sustainable remediation approach. Therefore, the aim of this study is to investigate the effect of LDH and BCLDH on reducing the uptake of some heavy metals, including lead, cadmium, nickel, and zinc, in basil plants during irrigation with landfill leachate and industrial wastewater.

Materials and Methods

The LDH and BCLDH were synthesized using the co-precipitation method. The landfill leachate was sampled from the Sari landfill site, and the industrial wastewater was collected from Sari Industrial Park No. 1. A split-plot design with 3 replications was used for this study, where the main factor was the type of irrigation water, including two types: landfill leachate and industrial wastewater. The sub-factor consisted of treatments with LDH and BCLDH amendments, arranged in a completely randomized design with 7 treatments as follows: 1- Control, 2- LDH 0.25%, 3- LDH 0.5%, 4- LDH 1%, 5- BCLDH 0.25%, 6- BCLDH 0.5% , and 7- BCLDH 1%. After mixing various amounts of LDH and BCLDH with 6 kg of dry soil, 10 basil seeds were planted in each pot. The irrigation method was based on weight loosing, meaning that before planting the seeds, the pots were first saturated with tap water according to their pore volume, and the weight of each pot after draining excess water was recorded as the initial weight. Two weeks after seed germination, irrigation with landfill leachate and industrial wastewater was conducted over 8 weeks based on the plants' evapotranspiration and the reduction in pot weight (after reducing the available water up to 75%). Finally, after harvesting the plants, the levels of heavy metals in the soil and plants were measured.

Results and Discussion

The results indicated an increase in soil pH up to 7.8 following the application of 1% BCLDH, probobly due to the effective role of biochar in raising soil pH. Morever, the results showed that the LDH and BCLDH amendments in irrigation with industrial wastewater had no significant effect on the levels of heavy metals in the soil and the basil in the roots, and shoots. In contrast, both application of LDH and BCLDH on irrigation of landfill leachate successfully minimized the metal levels in the soil and plant organs, with rate of BCLDH 1% showing the best performance. The lowest concentrations of lead, cadmium, and nickel in the soils were measured in the BCLDH 1% treatment, with values of 2.44, 0.18, and 1.64 mg/kg, respectively. Moreover, this treatment in landfill leachate irrigation reduced the concentrations of lead, nickel, and zinc in the shoots by 75.5%, 62%, and 36.4%, respectively. This effect is attributed to the clear role of LDH and its contribution in increasing soil pH, cation exchange, electrostatic adsorption, and the precipitation of metals into insoluble compounds in the soil. In addition, the modification of LDH with biochar improved its structure, increased its surface area, and enhanced its porosity, thereby reducing pore diameter. This led to the increased surface adsorption capacity, enhanced electrostatic adsorption, and more effective removal of heavy metals, which reached its peak in the BCLDH 1% treatment.

Conclusion

The present study focused on the beneficial role of LDH and BCLDH amendments in reducing the uptake of heavy metals (lead, cadmium, nickel, and zinc) by basil plants under irrigation with landfill leachate and industrial wastewater. The results do not support the hypotheis on use of these amendments for industrial wastewater irrigation, which is likely due to the inefficiency of amendments at low concentrations of heavy metals. On the other hand, the results demonstrated the high efficiency of BCLDH in reducing the uptake of heavy metals by basil during landfill leachate irrigation. The lowest levels of heavy metals were observed in the BCLDH 1% treatment in soil, roots, and shoots. This outcome highlights the successful synthesis of biochar on LDH, which improved the structure and increased the metal adsorption capacity of BCLDH. . In addition, the BCLDH 1% treatment increased soil pH, electrostatic adsorption, and cation exchange, thereby the reducing metal uptake by basil. Given that the uncontrolled use of effluents may lead to excessive accumulation of metals in the edible parts of plants and heightened concerns about human health, the application of BCLDH emerges as a effective approach for significantly improving plant performance and reducing heavy metal uptake and its associated consequences. However, before making the final recommendations, futhur studies should be conducted at the field scale, over multiple years, and using different plant species to ensure the effective and reliable outcomes.

Remediation of soil acidity is crucial for increasing crop production and improving environmental quality of acid infertile soils. Soil incubation and greenhouse pot experiments were carried out to examine the interactions between phosphate rock (PR), coal combustion by-product (BP), dolomitic lime (L), and cellulose (C) in an acidic soil and their effects on ryegrass (Lolium perenne L. cv ‘Linn’) growth. BP and PR application increased plant P content and dry matter yield (DMY) of shoots and roots by improving soil Ca availability and reducing Al toxicity. Application of BP at low rates (5 to 10 g BP kg-1) with PR appeared to decrease both plant P content and DMY compared to PR application alone. The reduced DMY is due to an increased Al concentration in soil solution as a result of displacement of sorbed Al by Ca of BP. Increases in DMY were obtained by addition of lime along with PR and BP at low rates or by increasing BP application rates above 15 g kg-1. This improved plant res...

This investigation designed and investigated a new compost to reduce the issue of soil erosion and organic wastes in Uzbekistan. Rice husks were co-composted with spent tea bags and cattle manure, and further improved via microbial bio-augmentation-using the phosphate solubilizing fungus, Aspergillosis niger, and the nitrogen fixing bacterium, Azotobacter chroococcum-or nano-augmentation with bentonite clay nanoparticles loaded with both iron and zinc. The resultant nanocompost (TMC+NP) was conducted to a pot trial compared to a control and conventional compost samples using the local saline and sodic soils to plant cabbage (Brassica oleracea) and carrot 2, Daucus carota). The TMC+NP treatment had a strong positive effect on the soil after 90 days of growth when salinity levels (EC) of the soil decreased by 22% and cationexchange capacity (CEC) was enhanced by 35% as compared to the control. It significantly boosted crop yield (up to 40 % improvement) and nutritional worth (an ascorbic acid (vitamin C) level by 15 987 position by 20 187 1) and levels of plant-acreptive iron and zinc by 20 187 1). The findings indicate valorization of local wastes to nano-bioaugmented compost as among the most effective yet sustainable approaches to dual purposes of soil remediation and crop biofortification has been provided as a solution of a scaled-up circleeconomy solution to arid and degraded agro-ecosystem.

Large scale afforestation of grasslands has occurred in New Zealand. Detailed investigation of changes in soil properties over time following establishment of different tree species is necessary to understand the impacts of this land-use change on soil nutrient dynamics and availability. A field trial was established in 1999 comprising 4 replicate plots of three commercial tree species (Pinus radiata, Eucalyptus nitens, Cupressus macrocarpa). Soil samples were taken from each plot prior to tree planting and after 5 years growth (2004). Analyses of samples taken in 1999 showed that the topsoil (0-5 cm) had a low pH (5.1), with low to medium levels of total carbon (5.01%), nitrogen (0.43%), phosphorus (630 mg/kg), sulphur (510 mg/kg) and exchangeable base cations (7.52 cmol c /kg). Results for comparison between samples taken in 1999 and 2004 revealed a decrease in total C, N, P, S and exchangeable Ca and Mg confined to the 0-5 cm soil depth. The reductions were generally greater under P. radiata than E. nitens and C. macrocarpa. In contrast, inorganic and plant available Olsen P levels increased under all species. These findings confirm that afforestation of grassland has a major short-term impact on soil properties and processes.

O chá preto é uma das bebidas mais consumidas no mundo. Essa bebida é feita a partir da infusão de folhas processadas de Camellia sinensis, que é cultivada em mais de 30 países, tendo grande importância socioeconômica. Estudos sugerem que o chá tem efeito protetor contra diversos tipos de câncer e doenças cardiovasculares devido à presença de polifenóis denominados catequinas, que são oxidadas enzimaticamente durante o processamento das folhas, gerando uma mistura constituída principalmente de teaflavinas, teasinensinas e tearubiginas. A produção mundial de chá tem aumentado mais do que o consumo, provocando redução do preço que, juntamente com o aumento no custo de produção, implica a necessidade de alta produtividade e qualidade. Apesar disso, ainda não foram estabelecidos critérios precisos e eficientes para predizer a qualidade do chá a partir das folhas, bem como quais práticas agronômicas contribuem para o aumento da qualidade. No Brasil, a cultura do chá se concentra no Vale ...

Plantations of radiata pine (Pinus radiata) cover more than 4,000,000 ha worldwide [P.B. Lavery, D.J. Mead, Pinus radiata: a narrow endemic from North America takes on the world, in: D.M. Richardson (Ed.), Ecology and Biogeography of Pinus, Cambridge University Press, Cambridge, 1998, pp. 432-449]. In many areas, including the Ecuadorian Andes, these plantations have been established on former grasslands. Although this land use has grown over the past four decades in Ecuador, little is known about the effect of the change in vegetation cover on nutrient cycling in the high-altitude grassland systems where the plantations are frequently established. We examined changes in soil nitrogen, phosphorus, and acidity with stand age, using a chronosequence of stands ranging from 0 to 25 years of age. The effects of planting the grasslands with pine were most notable near the soil surface (0-10 cm), although in some cases changes deeper in the A horizon were also large. Total nitrogen concentrations became increasingly depleted along the chronosequence at intermediate depth (P ¼ 0:04), while N was gained in the litter (P ¼ 0:02) and upper-A horizon (P ¼ 0:001) until the plantations reached 20 years, at which point it again declined. In the top 10 cm, concentrations of NO 3 À increased dramatically under pine (P < 0:001), while NH 4 þ was lower than in grasslands (P ¼ 0:04). Unlike nitrogen, neither total nor available phosphorus was significantly altered by the change in vegetation. Soil pH was higher in the grassland soils (5.5) than under pine stands of any age (P < 0:01), all of which had a mean pH of 5.2. Acidification under pine occurred only in the top 10 cm, with no differences in pH at other depths, indicating that it is being driven by soil processes that predominate in the near-surface environment. These results demonstrate that the change of vegetation can affect soil properties on a decadal time scale, with implications for long-term site productivity.

Background and Purpose: Mycorrhizal fungi are of high importance for functioning of forest ecosystems and they could be used as indicators of environmental stress. The aim of this research was to analyze ectomycorrhizal community structure and to determine root colonization rate with ectomycorrhizal, arbuscular mycorrhizal and endophytic fungi of poplars growing on pyrite tailings contaminated site near the river Timok (Eastern Serbia). Materials and Methods: Identification of ectomycorrhizal types was performed by combining morphological and anatomical characterization of ectomycorrhizae with molecular identification approach, based on sequencing of the nuclear ITS rRNA region. Also, colonization of poplar roots with ectomycorrhizal, arbuscular mycorrhizal and dark septated endophytic fungi were analysed with intersection method. Results and Conclusions: Physico-chemical analyses of soil from studied site showed unfavourable water properties of soil, relatively low pH and high content of heavy metals (copper and zinc). In investigated samples only four different ectomycorrhizal fungi were found. To the species level were identified Thelephora terrestris and Tomentella ellisi, while two types remained unidentified. Type Thelephora terrestris made up 89% of all ectomycorrhizal roots on studied site. Consequently total values of Species richness index and Shannon-Weaver diversity index were 0.80 and 0.43, respectively. No structures of arbuscular mycorrhizal fungi were recorded. Unfavourable environmental conditions prevailing on investigated site caused decrease of ectomycorrhizal types diversity. Our findings point out that mycorrhyzal fungal community could be used as an appropriate indicator of environmental changes.

Alfalfa is the most important forage legume in our agroecological conditions for feeding cattle. In the area of Jablanica district, alfalfa occupies a considerable place in the total plant production. The restrictive factor in the establishment and short durability of alfalfa stand is the low pH of arable agricultural soil. Within the three-year field trial on Vertisol soil type (pH in KCl 4.9), from 2016 to 2018, alfalfa plot yield has been analyzed with different fertilization variants. The research results indicate that alfalfa provides a significantly higher yield on the plot where amelioration measures were applied, through the application of limestone and manure, with the addition of mineral fertilizer. A barely lower yield was achieved on the calcified and manured plot, while the lowest yield was on the control plot, where a generous amount of mineral fertilizer was added, which is a common practice of agricultural producers in the area of Jablanica district.

Soil acidity is one of the major limiting factors to acid sensitive crop production like barley (Hordeum vulgare L.). The study was conducted on soils of three land uses (forest, grazing and cultivated) in Guto Gida District of the East Wollega areas of Oromia Region, Ethiopia. A greenhouse incubation experiment was employed to assess the effects of lime rates (0, 2, 4, 6, 8 and 10 tons ha ) on selected soil chemical properties, 1 barley P-uptake and its grain yield. Data generated was subjected to analysis of variance (ANOVA) using SAS software version, 9.1. The main effects of applied lime rates and interactions effects between lime rates and soils from different land uses significantly (P&lt;0.001) affected soil pH, the concentration of Al saturation, barley P uptake and its grain yield. Greenhouse incubation of soil with100 mesh size lime for 90 days reduced the percent acid saturation from 10 in the 0 t ha to 0.8 % at 10 t ha lime rate in soils of the forest land and for the gr...

The objective of this study was to assess and explore the effect of land use types on selected soil property of Dire Enchini District. Three composite of representative soil samples from depth of (0-25cm) were collected randomly from (Cultivated, grazing and forest) lands which were adjacent to each other and subjected to laboratory analysis. Physicochemical results was analyzed by One way ANOVA (P&lt;0.05) was employed to compare the mean of soil parameter. The textural classes of present study area were clayey dominated. As the depth increase bulk density increase in all selected land uses due to soil organic matter decrease and compactness by field traffic. However, the total porosity of present study result by two depths indicated as the depth increase the mean value of total porosity decrease. Generally the values show that the overall soil condition in the present study area appropriate condition in forest and cultivated lands than grazing land. Because of grazing land has the...

The prevalence of virulent Rhodococcus equi in isolates from soil and feces of foals on a farm with endemic R. equi infections was significantly higher than that of a farm with no history of the disease. Foals bred on a farm with the endemic disease might be constantly exposed to virulent R. equi in their environment.

The prevalence of virulent Rhodococcus equi in isolates from soil and feces of foals on a farm with endemic R. equi infections was significantly higher than that of a farm with no history of the disease. Foals bred on a farm with the endemic disease might be constantly exposed to virulent R. equi in their environment.

Mediterranean ecosystems have a net input of bio-elements every year that tends to neutralize de soils; an excess of winter rainfall only results in an acidification of soil epipedon (Ah). A fraction of the forest litter is recalcitrant and remains as humic substances (with relatively high content in N, P, and micronutrients) in the soil favored by the contrasting wet and dry seasons. In these Mediterranean’s acid soils, the presence of sesquioxides permits the sorption of bio-elements, resulting in clean surface water (Rivers, arroyos, etc.) of high quality if erosion is low or controlled. An increase in rainfall (e.g., due to climatic change) will have slight influence of the content and quality of soil organic matter, but could acidify the soil epipedon and diminish litter production; whereas an increase of ambience temperature could have and opposite results. By contrast, a change in rainfall annual distribution could have a strong influence on the above-ground productivity of these forests, and on the mineralization and turnover of organic matter.

Dissecting the phenotypic diversity of Ethiopian barley (Hordeum vulgare L.) genotypes through variance components and multivariate analysis Abstract: Exploring the genetic diversity of barley germplasm conserved in the gene bank is critical for climate-resilient breeding. This study explored the phenotypic diversity and associations of 10 quantitative agro-morphological traits among 229 Ethiopian barley genotypes to identify desirable traits and promising accessions. The experiment was conducted at Holeta Agricultural Research Center in 2023 using an augmented design. The result of the analysis of variance revealed significant variation among the studied genotypes. A significant variability and wide range of mean performance were observed for the studied traits. Key traits like heading and maturity, grain filling period, 1000-kernel mass, kernel number per spike, and productive tillers were the most discriminating traits contributing to the highest variability (46.9 %). Cluster analysis identified three major trait-specific clusters. Grain yield exhibits a moderate correlation with plant height and kernel number per spike. High phenotypic and genotypic coefficients of variation were obtained for grain yield, productive tillers, kernel number per spike, and spikelet per spike. In addition, high heritability and genetic advance were observed for days to heading, productive tillers, spike length, kernel number and spikelet per spike, and grain yield suggesting selective breeding for these traits is likely to be effective for crop improvement programs.

Quantitative aspects of fecal Rhodococcus (Corynebacterium) equi in newborn foals for 12 weeks after birth were investigated on two horse breeding farms. R. equi was found in the feces of foals during week 1 of life. The greatest numbers of R. equi were present in the feces of foals during the first 8 weeks of their lives, which coincides with the age when foals are most liable to be exposed to R. equi.

Organic farming systems are gaining popularity as agronomically and environmentally sound soil management strategies with potential to enhance soil microbial diversity and fertility, environmental quality and sustainable crop production. This work aimed at understanding the effect of organic and conventional farming on the diversity of soybean nodulating bradyrhizobia species. Field trapping of indigenous soybean Bradyrhizobium was done by planting promiscuous soybeans varieties SB16 and SC squire as well as non-promiscuous Gazelle in three organic and three conventional farms in Tharaka-Nithi County of Kenya. After 45 days of growth, 108 nodule isolates were obtained from the soybean nodules and placed into 13 groups based on their morphological characteristics. Genetic diversity was done by polymerase chain reaction (PCR) targeting 16S rDNA gene using universal primers P5-R and P3-F and sequencing was carried out using the same primer. High morphological and genetic diversity of t...

Soils in an agricultural landscape on the southern coast of Finland (60° 13'N 25° 02'E) were characterized and classified according to Soil Taxonomy, the FAO-Unesco system (FAO), and the World Reference Base for Soil Resources system (WRB). The impact of human activity (<500 years) on the soil forming processes was discussed. The cultivated land studied (200 ha, elevation of <1 to 10 m) consists primarily of lacustrine sediments. It is surrounded by forested bedrock high areas dominated by Spodosols/Podzols, and by reedy wetlands, partially occupied by Sulfaquents/Thionic Gleysols. Cultivated pedons had mollic or ochric epipedons and cambic horizons. High base saturation of epipedons is likely man-made by liming. These soils have naturally high water tables and the development of the cambic horizons has been significantly promoted by artificial drainage (ditches >150 years ago, tile lines at the depth of 1 m in the 1950s). They now meet the criteria for Mollisols and Inceptisols (Soil Taxonomy), Phaeozems and Gleysols (WRB), and Cambisols (FAO and WRB) but before drainage were likely Entisols (Soil Taxonomy) or Gleysols (FAO and WRB) with ochric, umbric, or histic epipedons and without a diagnostic B horizon.

Malawi has an agro based economy which relies mostly on exports of agricultural commodities. Improvement in agricultural production will depend on use of cheap fertilizers. Locally produced fertilizer from locally available resources could be cheap with reduced transport and port charges. An analysis has been done on fertilizer raw materials and their need for use in targeted compound fertilizer production is recommended to allow efficient crop response to fertilizer.

This study investigated the ionic speciation of reclaimed urban wastewater (RWW), and the impact of increasing RWW irrigation rates on soil properties and plant nutrition under field conditions. Most RWW elements (>66%) are readily available as NH 4 + , Ca 2+ , Mg 2+ , K + , SO 4 2-, Cl -, H 3 BO 3 , Mn 2+ and Zn 2+ , but in imbalanced proportion for plant nutrition. Lead, Cd, Cr and Al in RWW are mostly bounded with DOM or OH -. . Irrigation with RWW decreased soil acidity, which is beneficial to the acidic tropical soil. Although RWW irrigation builds exchangeable Na + up, the excessive Na + was leached out of the soil profile after a rainy summer season (>400 mm). Benefits of the disposal of RWW to the soil under tropical conditions were discussed, however, the over irrigation with RWW (>100% of crop evapotranspiration) led to a nutritional imbalance, accumulating S and leading to a plant deficiency of P and K.

Worldwide increase in food production programmes is important to check rise in population across the world. Due to this production cycles available piece of land is reduced leading to soil deterioration and conversion of virgin land to cropping activities further deteriorate the soil properties. Agricultural programme faces a lot of challenges in the tropics such as decrease in plant nutrient elements and faster depletion of organic matter due to intense rainfall and temperature. As effect, the cation exchange capacity

Garden egg is a vegetable valued for its nutritional and economic benefits. Its production is often constrained by poor soil fertility and weed competition interference. Improving soil fertility could enhance crop tolerance to weed competition. Therefore, this study investigates the influence of poultry manure (PM) on garden egg's resilience against weed competition. In a 4×2 factorial combination, PM at 0, 15, 30, and 45 kg N/ha represented as control, low, moderate, and high soil fertility conditions, respectively, and weed management (weedy check and regular weeding) were evaluated in a randomized complete block design replicated three times. Garden egg (L01 variety) seedlings were transplanted at 40,000 plants/ha. Data on growth and yield were subjected to ANOVA, and significantly different means were separated using Duncan's Multiple Range Test at p<0.05. The results showed that applying 45 kg N/ha of PM significantly increased plant height, number of leaves, and canopy spread compared to the other treatments in the first and second seasons. Variations in the growth parameters observed were significant (p < 0.05) for weed control. Weeded plots had 1274.67 and 1359.98 cm² leaf area, while non-weeded plots had 862.89 and 905.16 during the first and second seasons, respectively. The combination of 45 kg N/ha and regular weeding resulted in the highest fruit yield (6502.47 and 6004.10 kg/ha) and the lowest in the control treatment (0.00 and 125.00 kg/ha) in the first and second seasons, respectively. Applying poultry manure at 45 kg N/ha, with regular weeding, is more effective for garden egg production.

A produção de café conilon em sistemas de manejo orgânico tem aumentado no estado do Espírito Santo, no entanto, informações sobre o impacto desse manejo nas características químicas do solo são poucas e inconclusivas.Objetivouse, neste trabalho, avaliar o efeito de manejos de adubação orgânica sobre atributos químicos de solo, em agroecossistema de café conilon. Em uma lavoura localizada no município de Linhares-ES, foi montado, experimento em delineamento de blocos casualizados com distribuição fatorial 2 x 2 x 5, com três repetições, sendo os fatores: dois compostos orgânicos; presença e ausência de leguminosa; e cinco proporções de cada composto (0; 25; 50; 75; e 100%) em substituição à adubação mineral recomendada. Cada repetição foi composta por uma parcela de 30 plantas de café, sendo 12 úteis centrais. Os compostos foram: composto 1, preparado com capim-elefante e palha-de-café na proporção 1:1 (v:v); e composto 2, preparado com capim-elefante, palha-de-café e cama-de-frango na proporção 2:1:1 (v:v:v). A leguminosa utilizada foi o feijão-de-porco, semeada nas entrelinhas dos cafeeiros. Com a utilização de 100% do composto 1 e composto 2, o pH atingiu valores de 6,5 e 6,3, respectivamente em relação ao pH 4,8, obtido com a adubação mineral. As médias obtidas para a soma de bases (SB) acompanharam o comportamento das bases trocáveis (Ca, Mg e K) do solo, ou seja, aumentaram de forma linear (p<0,10), com o aumento das proporções dos compostos. A adubação com compostos orgânicos é uma alternativa para melhorar a fertilidade do solo no agroecossistema de café conilon.

Pseudomonas inoculants may lose colony-forming ability in soil, but soil properties involved are poorly documented. Here, we tested the hypothesis that soil acidity could reduce persistence and cell culturability of Pseudomonas protegens CHA0. At 1 week in vitro, strain CHA0 was found as culturable cells at pH 7, whereas most cells at pH 4 and all cells at pH 3 were noncultured. In 21 natural soils of contrasted pH, cell culturability loss of P. protegens CHA0 took place in all six very acidic soils (pH < 5.0) and in three of five acidic soils (5.0 < pH < 6.5), whereas it was negligible in the neutral and alkaline soils at 2 weeks and 2 months. No correlation was found between total cell counts of P. protegens CHA0 and soil composition data, whereas colony counts of the strain correlated with soil pH. Maintenance of cell culturability in soils coincided with a reduction in inoculant cell size. Some of the noncultured CHA0 cells were nutrient responsive in Kogure's viability test, both in vitro and in soil. Thus, this shows for the first time that the sole intrinsic soil composition factor triggering cell culturability loss in P. protegens CHA0 is soil acidity.

Soil acidity, a significant form of chemical soil degradation, is one of the most pressing challenges in Ethiopia, particularly in the highlands. It severely impacts agricultural productivity across much of the country. Owing to its impact on crop production and productivity, it is a critical issue that requires immediate attention in most highlands in Ethiopia. This study was conducted at the Lalistu Cheri watershed, which is located in the Sibu Sire District of the western zone of the Oromia region, Ethiopia, with the objective of characterizing and assessing the soil acidity status under different land use types and soil depths. Replicated composite soil samples were collected from three representative land use types (cultivated, grazing, and eucalyptus plantation lands) and two soil depths (0-20 and 20-40 cm) by X-patterns along transects and analyzed via standard laboratory procedures. The results revealed spatial variation in the soil properties among the land use types and soil depths. The soils in both cultivated and eucalyptus plantation land were strongly acidic (pH<5.5), whereas those in grazing land were moderately acidic. The highest (54.89%) and lowest (43.73%) clay contents were recorded in the soils of cultivated and grazed lands, respectively, whereas the sand content was greater (36.11%) in the eucalyptus plantation land. The relatively highest bulk density (1.36 g cm-3) was recorded in the grazed land soils, followed by the cultivated land soils (1.32 g cm-3). Both the exchangeable acidity and aluminum content in all land use types decreased with increasing soil depth, which was consistent with their acid saturations. The organic carbon content ranged from 2.30% at the subsurface layer of the cultivated land to 3.44% at the surface layer of the grazing land soils, whereas the total nitrogen content ranged from 0.19% to 0.30%. Available P ranged from 7.31 mg kg-1 to 12.61 mg kg-1. The highest Ca, Mg, Na, and K contents (8.92, 5.76, 0.30, and 1.26 Cmol (+) kg-1 , respectively) were recorded in the soils of the grazing land. The amount of PBS used ranged from 35.14% to 78.45%. The CEC and ECEC of the soils in the three land use types also increased consistently with increasing soil depth. Micronutrient concentrations decreased with soil depth. The Fe and Mn contents ranged from 0.54 and 4.42 mg kg-1 in the subsurface layer of the grazing land and eucalyptus plantations, respectively, to 10.58 and 12.14 mg kg-1 in the surface layer of the eucalyptus plantations and grazing land soils, respectively. Cu and Zn also ranged from 1.52 and 0.29 mg kg-1 to 3.16 and 0.85 mg kg-1 , respectively. The study suggests that both CL and EPL soils exhibit the highest acidity and require soil management practices, such as lime application, to reduce acidity and improve soil fertility. On the other hand, GL soils show more favorable conditions for nutrient retention and pH.

Land degradation is a worldwide concern, and degraded grassland and sown pasture may represent up to 60% of the total grassland area in many regions. In the acid-soil savannas of Eastern Colombia, on-farm beef production declines with the increasing age of tropical pastures, even if grazing is well managed. There is limited knowledge of how pasture age quantitatively affects the performance of grazing cattle in these pastures. Using a set of observational studies, this study aimed to quantify the decline in the performance of animals grazing reasonably stocked and well-managed pastures over time in the Eastern Plains of Colombia in farms that vary in soil texture and pasture management practices. Grass-only farm pastures that were monitored over a span of 6–15 years exhibited a yearly decline in liveweight gains (LWG) during the rainy season (7–10% per year) as they aged, even when forage availability was non-limiting, as determined via formal, on-station experiments. Furthermore, rainfall during the 8-year study period showed little variation between successive years, and it was inferred that it did not limit grass growth. However, it is noteworthy that in the few cases when persistent legumes were incorporated into the grass, LWG were either preserved or declined very slowly. The quantitative changes in yearly decline in LWG observed in this study, together with the published evidence from similar acid-soil savanna environments, suggest that the principal factor driving pasture decline is low soil N supply. In addition, phosphorus (P) deficiency, soil texture, and limited water infiltration may also be factors involved in pasture decline. The observed trends in declining animal performance with pasture age are not unique to the acid soils of the Eastern Plains of Colombia since similar patterns have been documented globally. It is therefore important to account for these trends when developing regional plans aimed at intensifying beef cattle production since short-term observations may lead to overoptimistic projections.

SUMMARY A pot experiment was conducted at Michael Okpara University of Agriculture Umudike to evaluate the effect of cocoa husk ash in ameliorating soil acidity and improving maize yield. Five levels of the cocoa husk ash at 0,2,4,6 and 8 t/ha were applied and replicated three times in a completely randomized design. The results obtained showed that different rates of

This study was carried out to delve into the ameliorating capacity of amendments on soil acidity and growth yields of tomatoes. This study was set up using a fully randomized approach by two factorial experiments of 0, 2.5, 5, and 7.5 tha-1 vermicompost and 0, 4, 6, and 8 tha-1 of lime with two replications. The findings indicated that the integration of lime and vermicompost performed well in amending soil acidity and improving selected yields of tomatoes. Soil pH significantly increased from pH (4.99) to pH (5.53) and increased soil nutrient availabilities, phosphorus to 6.20 mg kg⁻¹, organic matter to 5.30%, and total nitrogen to 0.20% by the use of vermicompost and lime together. In addition, the highest plant height (6.84 cm) and maximum dry weight per plant (0.092 g plant⁻¹) were obtained under-treated soil. Therefore, the soil fertility was unlocked, the acidity of the soil was amended, and the growth yields of tomatoes improved by the application of vermicompost and lime treatments. From this finding, further field experiments are recommended to analyze the effects of amendments at smallholder farmers' levels at different locations with different ecologies.

Increase in human population and land degradation leads to decrease
microbial load in soil due to this the soil health as well as the plant yield
is severely affected thus an effective way to increase the microbial load
in soil is by application of inoculants. Inoculants includes different
living strains like bacteria, fungi, algae and other combinations of
microbial organisms. Biofertilizers and microbial innoculants have
greater potentiality in improvement of the soil quality and helps in
management of nutrients. Yield maximization without degradation of
the environment can be made possible with the help of microbes.

Soil are precious materials which are abundant in earth system that has
an ability to grow crops and produce food for feeding the world’s need.
But due to ongoing crisis of growing population, the need of food
security got emerges. But fulfilling’s individual food satisfaction, the
proper yield outcome should be notified. But everyone failed to notice
the nutrient status of soil irrespective of its yield. But without advanced
technology in nutrient management study of soil, the targeted outcome
can’t be achieved. One of the present technology which boosts the
agricultural productivity and good yield is Nanotechnology. It has
emerged as the revolutionary bringing in order to fulfill the demand of
ever-growing population, making a way for sustainable agriculture.
But in recent times, these Nano-science concept had extend its
application towards other like plant-microbe interaction, soil
metagenesis, etc. These nanoparticles are small in size (one-billionth of a meter) which reduces the bulk application over fertilizer requirement
in soil, other pesticide molecule reduction and so on. Hence these
technology had a promising impact over soil nutrient management. But
concerning it in the way of positive as well as negative depends upon
usage of an individual. Hence it has both positive and negative impact
which was spelled by different research experts. Recent research focus
upon releasing pattern of Nano-urea, which are encapsulated or coated
within nanomaterial in order to enable controlled release, and its
subsequent slow diffusion into the soil.This chapter provides the
comprehensive review about importance and trends of nanotechnology
for efficient soil nutrient management.

Soil acidification is already a biggest concern in the country, affecting
about 48 million hectares (mha) out of 142 mha of arable land. It is
considered as the major constrain and it affect both soil and plant
nutrient uptake. This severity of soil leads to prominent yield loss. Over
30 per cent of cultivable land in India is said to carry acidic soil,
impacting plant growth. Also due to prolonged acidity, prevalence of
loss on soil inorganic carbon, a stable carbon pool which may leads to
carbon loss in soils. Suitable management practices are needed in order
to reclaim acidity to get profitable income for the farmers. But recent
days, the development of acid soil are dominant due to adverse climatic
change since, humid climate favours acid soil formation. Soil is acidic if
pH is less than 7 and alkaline if it is above 7.0. Plants suffer from
suboptimal availability of nutrients at pH below 5.5 and above 8.5 resulting in lower yield of arable crops. Also this acidification affects
the uptake of other nutrient availability. Hence, to overcome these
potential constrain, proper management practices is necessary to
reclaim from acid soils and to increase crop yield, nutrient availability.
Practices include liming, liming materials, slags, bio-char amendment
etc.

Lead and other heavy metals are chemically fixated using the MAECTITE® treatment process. Treatment reactions convert leachable metal species to geochemically stable and hardened mixed mineral forms within the waste matrix that are resistant to EPTOX, TCLP, MEP, acid-leach and other test methods utilized to define RCRA toxic waste and waste product longevity. Case history data from comprehensive treatability studies support process utilization on all soil types examined, debris, and solid waste consisting of battery casings, lead projectiles, sludges, slag, paint chips with abrasives, and other waste material types. Through detailed remedial work plans and other mechanisms combining engineering, geologic, soil science, and operational construction disciplines, full-scale MAECTITE® processing at RCRA, NPL, emergency response, and other lead contaminated sites on private, state, and federally funded projects have been successfully addressed. The MAECTITE® process has been patented and...

The contribution of appropriate inoculum strains to more efficient nitrogen fixation by legumes has been difficult to assess due to the laborious nature of the assays involved in assessing establishment of inoculum strains in the field. The use of marker genes, in particular the GUS system, changes this, making it possible to assess occupancy by the inoculum strain in large numbers of nodules on whole root systems. The GUS [Β-glucuronidase] system was used to evaluate the competitive ability of two rhizobial strains, Rhizobium leguminosarum bv. phaseoli strain Kim5 and R. tropici strain CIAT899 in two soil types from Kenya. The results confirm that Kim5 is a highly competitive strain, forming 86% of the nodules in a near-neutral pH soil. Although the competitiveness of CIAT899 is enhanced in an acid (pH 4.5) soil it still only formed 35% of the nodules. There were no differences between inoculum strains in their efficiency of nitrogen fixation in either soil type, and virtually no N 2 -fixation occurred in the acid soil due to the lack of tolerance of the Phaseolus genotype to soil acidity.

The annual average area sown with barley (Hordeum vulgare) in South America during 1999–2003 was 795 000 ha. In Argentina, Brazil, Chile and Uruguay, two-rowed spring cultivars are used mostly for malt production. Research has been developed in private malting companies and official institutions supported by the industry. In Argentina, tolerance to drought and heat stress during grain filling are important in drier areas. Yield and malt extract had been improved in cultivars released from 1940 to 1998. In Brazil, progress in grain yield, grain size, malting quality, early maturity, and resistance to net blotch, powdery mildew, and leaf rust has been achieved by EMBRAPA and malting companies. Higher tolerance to soil acidity and resistance to spot blotch are required. Since 1976, malting barley breeding in INIA-Chile has improved grain yield, grain size, beer production efficiency, and resistance to scald, net blotch, stripe rust, and leaf rust. Uruguay produces high quality malt exp...

Soil properties of terrestrial ecosystems are controlled by a variety of factors that operate at different scales. We tested the role of abiotic and biotic factors that potentially influence spatial gradients of total ion content, acidity, carbon, total nitrogen, and total phosphorous in topsoil. We studied a network of Mediterranean montane meadows that spans a 2000-m altitudinal gradient. The analyzed factors were grouped into two spatial scales: a landscape scale (climate and land form) and a field scale (topography, soil texture, soil moisture, and plant community composition). Total ion content and acidity are the major and independent variation trends of soil geochemistry. Soil acidity, carbon, and nitrogen increased along the altitudinal gradient whereas there was no relationship between total ion content and phosphorous and elevation. Climate had not a direct influence on the analyzed gradients; all effects of climate were indirect through plant community composition and/or soil moisture. The results point to three types of models that explain the gradients of soil chemical composition: (1) a predominantly biotic control of carbon and nitrogen, (2) a predominantly abiotic control of acidity, and (3) a combined biotic and abiotic control of total ionic content. No direct nor indirect effects explained the gradient of phosphorous. In our study region (central Spain), climate is predicted to turn more arid and soils will lose moisture. According to our models, this will result in less acid and fertile soils, and any change in plant community composition will modify gradients of soil carbon, nitrogen, total ion content, and acidity.

Se evaluó el efecto de la corrección de la acidez del suelo, con diferentes fuentes de Ca y Mg, sobre el desarrollo inicial del sistema radical del palmito bajo condiciones de invernadero. Se utilizó 2 órdenes de suelos: Andisol y Ultisol, provenientes de zonas cultivadas de palmito de pejibaye. Plántulas pregerminadas de palmito fueron colocadas en macetas de 3,6 l las cuales recibieron fertilización básica correspondiente a 600, 130 y 370 kg ha -1 de N, P 2 O 5 y K 2 O, respectivamente. Los tratamientos evaluados fueron: testigo y neutralización total de la acidez con CaCO 3 y MgCO 3 . Las variables evaluadas fueron altura de la planta, número de hojas y peso seco de la parte aérea y longitud del sistema radical, determinado por el método de escáner "Root Law". Al final del ensayo se realizó un análisis de suelo y foliar de los tratamientos. El análisis estadístico mostró un efecto significativo de los tratamientos en ambos suelos. El efecto de los tratamientos, en general, no fue significativo para las variables peso seco de la parte aérea ni para los contenidos de S y Fe. La interacción suelo x tratamiento fue significativa para los contenidos de Ca, Mg, K, y S foliar y tamaño de raíces, no así para el resto de variables analizadas. En el suelo, al final del experimento, se encontró un ABSTRACT Ameliorization of soil acidity with Ca and Mg on the development of peach palm root system at the pre-nursery growth stage. The effect of ameliorization of soil acidity with different sources of Ca and Mg on the initial development of the root system of peach palm was evaluated under nursery conditions. Soils classified as Andisol and Ultisol were used, as they represent the major soil orders of peach palm plantations of Costa Rica. Pre-germinated seedlings were planted in pots of 3.6 l with a basic fertilization of 600, 130 and 370 kg ha -1 of N, P 2 O 5 y K 2 O, respectively. Treatments evaluated were: control and total neutralization of acidity with CaCO 3 and MgCO 3 . Plantlets height, leaf number and dry weight were evaluated for the above-ground part, and the lenght of the root system determined by the scanner method "Root Law". At the end of the test, soil and leaf analyses around treatments were carried out. An statistical analysis of variables showed a significant effect of treatments on both soils. In general, treatments had no significant effect on dry weight and Fe foliar contents. The interaction soil x treatment was significant for Ca, Mg, K and foliar S contents, as well as for root size, not so for other 1/ Recibido para publicación el 18 de marzo del 2002.

Integrated crop-livestock systems have been indicated as alternatives to intensify land use. However, the soil water dynamics for proper water resources management is still poorly understood in such systems. This study aimed to assess the impact of grazing intensities on soil and black oat plants water status in a long-term, no-tillage, integrated soybean-beef cattle system. The experiment has been carried out since 2001 with a soybean and cattle grazing on black oat + ryegrass pasture succession. Treatments consist of different grazing intensities regulated by the pasture sward height, namely: intensive grazing (10 cm sward height), moderate grazing (20 cm sward height) and non-grazed. Soil bulk density was determined after soybean harvest. Soil moisture and water status of the black oat plants were monitored from the pasture sowing until the animal removal from the area, by the evaluation of leaf temperature and water potential. Grazing season begins with similar surface soil bulk...

This study aimed to evaluate the effect of substituting chemical nitrogen (N) fertilization for equivalent N levels from sewage sludge of Wastewater Treatment Plant (WTP) on sunflower plant development. Nutrient levels in physiologically mature leaves and seeds, besides nutrient exportation during a 130-day assay, were also assessed. The experiment was carried out in 100 m 2 permanent plots at São Manuel Farm, which belongs to

Se evaluó el efecto del encalado en el ren-dimiento de naranja Valencia y en la fertilidad de un Ultisol de la Zona Norte de Costa Rica. Se utilizó 3 materiales de encalado: CaCO3 de granulometría gruesa; CaCO3 de granulometría fina; y una mezcla física de 85% de CaCO3 y 15% de ...

En Chiapas, Veracruz y Puebla, las enfermedades son uno de los principales factores que reducen el rendimiento de frijol. Los objetivos del trabajo fueron determinar el comportamiento productivo de genotipos de frijol negro en temporal y humedad residual y su reacción a enfermedades. En 2008 se estableció un ensayo en Ocozocoautla, Chiapas, Orizaba, Veracruz y Tecamachalco, Puebla, en temporal y en Medellín de Bravo y San Andrés Tuxtla, Veracruz, con humedad residual. Se evaluaron 11 variedades y cinco líneas, en diseño látice 4 x 4 con cuatro repeticiones. En campo se cuantificó su reacción al virus del mosaico común, mancha angular, roya y antracnosis, con la escala de 1 a 9 del CIAT, así como el rendimiento de grano en kilogramos por hectárea. Se realizó análisis de varianza de cada enfermedad, las cuales se correlacionaron con el rendimiento de grano. Así como análisis combinado del rendimiento de los genotipos por condición de humedad y análisis de conjunto de todos los ambientes de prueba. Para la separación de promedios se aplicó la DMS al 0.05. Negro Papaloapan rindió 1 753 kg ha -1 en temporal y 1 333 kg ha -1 con humedad residual; ambos rendimientos promedio fueron estadísticamente superiores al del resto de los genotipos. La

We characterize land use at the household level and identify two types of long-term uncultivated lands–those that are intentional fallows and those that are neglected or abandoned. We then use a multinominal logit model to examine the determinants of plot abandonment and long fallows in order to propose policy interventions that lead to optimal and sustainable management of land use systems in Kigezi highlands. Household factors such as age, and formal education positively influenced farmers’ decision to abandon plots.. However, farm size and household type had no significant influence on abandonment of plots. Plot variables such as slope and distance between the homestead and the plot had the expected positive signs while soil fertility had a significant negative sign as predicted. From the analysis different typologies of uncultivated lands were defined depending on their inherent characteristics and distance to the homestead. Farmers then provided technological and policy options...

Maharloo Lake covers an area of 257 km2 that located on 18 km East of Shiraz city. This research aimed to investigate the
vegetation of lake's western border land. At first location, geology, hydrogeology, pedology and climatology were studied.
Aim of this research is relationship between water table depth and EC and pH of soil with vegetation. Because of it, in first
step, vegetation types were made on the basis of geomorphology of region and then within each vegetation type, sampling
the vegetation completely randomly by transect method using transect of 30 m and 3 transects per each type. In each type,
sampling soil to a depth of one meter by foreseeing two depths (first depth 0-50 cm and second depth 50-100 cm) were
done and soil samples tested by experiments involving saturated percentage, electrical conductivity, pH of soil and texture.
Total depth of groundwater obtained using total station camera and the topographical maps and wells in the area and field
studies. Finally, according to data obtained from vegetation studies, soil and underground water depth, the relationship
between these factors was obtained by Pc-ordination software and by Canonical Correspondence Analysis (CCA) was
analyzed.

Maharloo Lake covers an area of 257 km 2 that located on 18 km East of Shiraz city. This research aimed to investigate the vegetation of lake's western border land. At first location, geology, hydrogeology, pedology and climatology were studied. Aim of this research is relationship between water table depth and EC and pH of soil with vegetation. Because of it, in first step, vegetation types were made on the basis of geomorphology of region and then within each vegetation type, sampling the vegetation completely randomly by transect method using transect of 30 m and 3 transects per each type. In each type, sampling soil to a depth of one meter by foreseeing two depths (first depth 0-50 cm and second depth 50-100 cm) were done and soil samples tested by experiments involving saturated percentage, electrical conductivity, pH of soil and texture. Total depth of groundwater obtained using total station camera and the topographical maps and wells in the area and field studies. Finally, according to data obtained from vegetation studies, soil and underground water depth, the relationship between these factors was obtained by Pc-ordination software and by Canonical Correspondence Analysis (CCA) was analyzed.

SUMMARY A pot experiment was conducted at Michael Okpara University of Agriculture Umudike to evaluate the effect of cocoa husk ash in ameliorating soil acidity and improving maize yield. Five levels of the cocoa husk ash at 0,2,4,6 and 8 t/ha were applied and replicated three times in a completely randomized design. The results obtained showed that different rates of cocoa husk ash increased soil pH, total N, available P, exchangeable K, Ca and Mg. It also significantly increased the number of roots, plant height and dry matter yield when compared with the control. The 8t/ha of cocoa husk ash gave the highest maize dry matter yield of 163% over the control. Plant height, number of leaves, number roots and dry matter yield correlated positively with some soil chemical parameter except exchangeable acidity that correlated negatively with the yield parameters.