Compost Application Rates Research Articles

Emissions of CO2 and CH4 from Agricultural Soil with Kitchen Compost at Different Temperatures

Emissions of CO2 from the soil are mainly derived from soil microbial respiration, whereas CH4 emissions originate from anaerobic degradation of organic matter via microbial processes. Kitchen waste compost is used in the agricultural sector to improve soil quality. However, abiotic CO2 and CH4 emissions from soils amended with kitchen waste compost under aerobic conditions remain uncertain. Temperature plays an important role in organic matter decomposition in both biotic and abiotic pathways. This study aimed to evaluate biotic and abiotic emissions of CO2 and CH4 from soils receiving kitchen compost at different temperatures. Ten grams of soil amended with or without 0.1 g kitchen compost (1%) were sterilized or non-sterilized. The mixture and soil-only samples were incubated in 100-mL glass bottles at 20, 30, and 35 °C for 28 d under an aerobic condition. The results showed that CO2 and CH4 emissions increased at higher temperatures and compost application rates (p < 0.05). Emissions of CO2 mainly occurred via biotic pathways. Abiotic processes were potential pathways for CH4 generation, particularly at high temperatures of 35 °C. There was 20–24% of C in kitchen compost changed to CO2 and less than 0.1% to CH4. Our results suggest that global warming enhances abiotic CO2 and CH4 emissions and may contribute to further global warming.

Investigating the Effects of Various Soil Amendments on Forages Production in the Field

An initial investigation into the utilization of recycled plant and animal residues as soil amendments (SAs), including compost, biochar, and soil conditioner, was conducted using alfalfa crops. This study evaluated the impact of SAs on alfalfa seed germination, resulting in an 87% germination rate for biochar, 82% for soil conditioner, and 82% for compost. In comparison, untreated seeds displayed a 78% germination rate. After successful germination, the SAs were employed to enhance soil health, with a focus on water conservation and increased forage yield. The study used sandy-textured soil with moderate alkalinity, very slight salinity, slight calcareousness, and high permeability. The germination trial confirmed that SAs usage did not hinder seed germination, even for salt-sensitive crops like alfalfa. Two field experiments were carried out in Al-Wafra, using different application rates of compost, biochar, and soil conditioner at 5, 7.5, and 10 tons per hectare. The results highlighted the positive impact of SAs application on increasing forage production, with varying degrees of enhancement, and confirmed a 40% reduction in water usage compared to treatment without SAs but under 100% irrigation (100% ETc). In conclusion, SAs show promising potential for local forages intensification and water conservation.

Mitigation of water stress by compost and arginine application and its impacts on barley production

BackgroundWater-scarce locations necessitate the deployment of creative and sustainable techniques for managing water for agricultural production. Field experiment was conducted at the Experimental Research Farm of National Research Centre, Nubaria region, Egypt to alleviate the harmful effect of water stress on the yield of Mediterranean barley varieties (Giza 125, Tombari, Ksar Megrine and Tamellat) by compost (0.0, 2.0, 4.0, 6.0-ton fed−1) and arginine application (0.00 and 1000 ppm) under deficit irrigation. The amounts of irrigation water applied were “900 and 450” m3 fed−1 to sufficient irrigation and deficit irrigation, respectively.ResultsThe greatest and most significant values of the chlorophyll values and relative water content values obtained at the treatment supplied with 6.0-ton compost fed−1 and sprayed with Arginine. There was a significant dramatic decrease in proline content with increasing compost application rates and treated barley plants by Arginine for all the studied barley varieties under both studied irrigation treatments. Increasing compost application rate is associated with significant increase in number of spike m−2 without or with arginine. Barley Tombari variety received 6.0-ton compost fed−1 gained changes to give a greatest significant value of grain (ton fed−1) under sufficient irrigation and Tamellat under deficit irrigation situation. The significant maximum values of the grain yield (1.96- and 2.09-ton fed−1) were attained at Tombari and Tamellat varieties which received 6.0-ton fed−1 compost with or without arginine under sufficient irrigation. The increases in compost rate increment changes to incremented grain yield values with arginine application more than untreated one. The greatest and significant grain yield was found at the treatment received 6.0-ton compost fed−1 with arginine foliar application.ConclusionCompost application has an important role in maintaining greatest water use efficiency for plant and arginine application reported to contribute in reduction in destructive effects of a biotic stress thus their importance in increasing the barley production under water stress.

Comparative efficacy of wheat-straw biochar and chicken-waste compost on cadmium contaminated soil remediation, reducing cadmium bioavailability and enhancing wheat performance under cadmium stress

Cadmium (Cd) pollution of soil and food crops is a widespread environmental issue caused by excessive industrialization, unsustainable urbanization, and intensive farming practices. Cd, a hazardous element, poses significant risks to agro-environmental sustainability, food safety, and human health. Using organic materials such as biochar and compost to stabilize Cd in contaminated soil is an environmentally benign and cost-effective strategy for remediating moderately to highly polluted soil. However, in response to the scarcity of comparative studies on biochar and compost efficacy, this research explores the impact of wheat-straw biochar and chicken waste compost on Cd-contaminated soil remediation. A greenhouse experiment using two application rates (1.5 % and 2.5 %) of biochar and compost in 10 mg kg−1 Cd-contaminated soil revealed significant (p≤0.05) effects. The 2.5 % compost application increased soil organic carbon (SOC) from 0.45 % to 0.85 %, while 2.5 % biochar enhanced soil pH from 7.1 to 7.7 and electrical conductivity (EC) from 0.33 to 0.44 dSm−1. Notably, 2.5 % biochar significantly reduced Cd bioavailability from 9.49 to 4.90 mg kg−1, root accumulation from 29.8 to 16.4 mg kg−1 and shoot translocation from 16.8 to 8.4 mg kg−1. This reduction was confirmed through translocation factor (51.5 %) and immobilization efficiency (48.4 %). Furthermore, 2.5 % biochar improved chlorophyll content (a, b, and total) and wheat morphological attributes under Cd stress in soil. Overall, higher rates of biochar (2.5 %) and compost (2.5 %) effectively mitigate Cd uptake, improve soil properties, and enhance physiological and morphological responses, suggesting their promise for sustainable soil management practices.

Dynamic changes in soil organic carbon induced by long-term compost application under a wheat-maize double cropping system in North China

Soil organic carbon (SOC) plays a vital role in improving soil quality and alleviating global warming. Understanding the dynamic changes in SOC is crucial for its accumulation induced by compost application in agroecosystem. In this study, soil samples were collected from three treatments: high-rate bio-compost (BioMh), low-rate bio-compost (BioMl), and control (CK, no fertilization) during 2002–2020 in a wheat-maize double cropping system in North China. The soils were separated into three functional fractions, i.e., coarse particle organic matter (cPOM, >250 μm), microaggregates (μAgg, 53–250 μm) and mineral-associated organic matter (MAOM, < 53 μm), and the associated SOC contents were determined. During 1993–2002, SOC contents in bulk soil significantly increased with the duration in the BioMh and BioMl plots. However, there was no significant correlation between SOC content and duration during 2002–2020. These results suggested that compost application positively improved SOC sequestration, while the duration of SOC sequestration (i.e., the longevity of increased SOC with time) under compost inputs maintained only 9 years. Moreover, there was a significant increase in mean annual SOC contents in bulk soil with compost application rate during 2002–2020, indicating that carbon saturation did not occur. Additionally, the SOC contents in the cPOM fraction increased with time (p < 0.01), but the corresponding μAgg and MAOM associated SOC was insignificant (p > 0.05). The MAOM fraction exhibited no additional carbon accumulation with expanding compost application, confirming a hierarchical carbon saturation in these fractions. We concluded that soils under wheat-maize double cropping system in North China have greater potential to sequester C through additional compost inputs, despite showing hierarchical saturation behavior in the non-protected coarse particulate fraction.

Comparative effect of different irrigation levels and soil amendments on cabbage productivity in semi‐arid Central Namibia

AbstractIn semi‐arid Central Namibia, poor sandy soils limit sustainable crop production. We assessed cabbage performance in two split‐plot field experiments. In Experiment 1, treatments comprised two irrigation levels: full irrigation (watered 3 days a week) and reduced irrigation (watered 2 days a week) as the main plot factor and six soil amendments (biochar; compost; zeolite; nitrogen, phosphorus potassium [NPK]; Be‐Grow boost [L] hydrogel; and hoof and horn + bone [HHB] meal) as subplot factors in three replications. Full irrigation produced a significantly higher yield (21.1 t ha−1), head weight (0.958 kg) and larger head girths (42.1 cm). Biochar produced the highest marketable heads (24,884 heads ha−1), water use efficiency (76.0 kg ha−1 mm−1) and the largest head girths (42.7 cm). In Experiment 2, water was applied 5 and 4 days a week for full and reduced irrigation; the application rates of compost, HHB meal, Be‐Grow boost (L) hydrogel and NPK were modified. The interaction of Be‐Grow boost (L) hydrogel, NPK and biochar with full irrigation and HHB meal with reduced irrigation produced more marketable heads (28,935, 28,009, 27,546 and 28,703 heads ha−1, respectively). Therefore, full irrigation with these amendments could be used for resilient cabbage production in Central Namibia.

Physiological responses of oregano under different water management and application of fermented bokashi compost

Growing conditions such as water supply and soil fertility influence oregano morphological development and physiological responses. Our study aimed to analyse the physiological responses of oregano plants grown under different water conditions and bokashi application rates. The experiment was carried out in a greenhouse under a randomized block design and a 3 x 4 factorial scheme. Treatments encompassed three water replacement levels (60, 80, and 100% crop evapotranspiration - ETc) and four bokashi rates (0, 100, 200, and 300 g m-2), with five replications each. Oregano seedlings were transplanted and grown in a spacing of 0.3 m between plants and 1 m between bed rows. After 60 days, treatments were evaluated for photosynthetic rate (A), stomatal conductance (Gs), internal CO2 rate (Ci), transpiration (E), and water-use efficiency (WUE). Data underwent variance analysis by F-teste, multivariate analysis, and Pearson's linear correlation. Oregano physiological responses were significantly influenced by water replacement level and the application rate of fermented bokashi compost. The multivariate analysis allowed us to analyse the interaction effect between water replacement level and bokashi rate on photosynthesis, stomatal conductance, internal CO2, and transpiration.

Importance of Application Rates of Compost and Biochar on Soil Metal(Loid) Immobilization and Plant Growth.

In this study, we investigated the effect of different rates of compost (20%, 40%, 60% w/w) in combination with biochar (0%, 2%, 6% w/w) on soil physiochemical properties and the mobility of arsenic (As) and lead (Pb), in addition to the ability of Arabidopsis thaliana (ecotype Columbia-0) to grow and accumulate metal(loid)s. All modalities improved pH and electrical conductivity, stabilized Pb and mobilized As, but only the mixture of 20% compost and 6% biochar improved plant growth. Plants in all modalities showed a significant reduction in root and shoot Pb concentrations compared to the non-amended technosol. In contrast, As shoot concentration was significantly lower for plants in all modalities (except with 20% compost only) compared to non-amended technosol. For root As, plants in all modalities showed a significant reduction except for the mixture of 20% compost and 6% biochar. Overall, our results indicate that the mixture of 20% compost with 6% biochar emerged as the optimum combination for improving plant growth and As uptake, making it the possible optimum combination for enhancing the efficiency of land reclamation strategies. These findings provide a foundation for further research on the long-term effects and potential applications of the compost-biochar combination in improving soil quality.

Short-term effects of increasing compost application rates on soil C and greenhouse gas (N2O and CO2) emissions in a California central coast vineyard

Compost application is commonly considered by winegrape producers to improve soil health while sequestering carbon (C) and mitigating climate change. However, inputs of available C and nitrogen (N) as nutrients can induce emissions of greenhouse gases (GHG) such as carbon dioxide (CO2) and nitrous oxide (N2O). A 2-year field experiment in a Mediterranean vineyard on the California Central Coast was conducted to investigate the short-term effects of compost application at four different rates on soil C dynamics and greenhouse gas emissions. Two years of greenhouse gas sampling were performed using static chambers at vineyard management events in two functional locations (tractor row and under the vines). Soil samples were collected annually in spring at the same locations at 0–15, 15–30 and 30–60 cm depth, and during greenhouse gas sampling at 0–15 cm. The increasing compost application rate did not increase soil C stock, cumulative greenhouse gas emissions and global warming potential. The increase in active soil C observed to the depth of 60 cm suggests that increasing the compost application rate up to the rate of 13.5 Mg ha-1 year-1 can facilitate the early stages of C stabilization and sequestration. Compost application did not have a significant effect on grape yield or cover crop growth during the study. Our results provided important information on the potential environmental tradeoffs as greenhouse gas emissions from compost applications, which should be taken into account when considering the vineyard C budget.

Effect of eucalyptus wood-based compost application rates on soil chemical properties in semi-organic avocado plantations, Limpopo province, South Africa.

Mixing different types of organic matters to form a compound compost can be useful in both short-and long-term improvement of soil chemical properties. However, effects of such composts on soil chemical properties are unknown. A 3-year field study was done to determine the effects of eucalyptus wood-based compost on selected chemical properties of soils at Mooketsi and Politsi avocado orchards, Limpopo Province, South Africa. The study was laid as a repeated measures design with 4 compost treatments at 0, 5, 10, and 15 t ha-1 year-1 with three replicates. Soil pH, EC, organic carbon, active carbon, soil NO3-N, NH4-N, PMN, P K, Ca, Mg, Na Mn, Cu, Zn, and Fe were measured annually at the two orchards after applying compost at the different rates. The eucalyptus wood-based compost significantly (p<0.05) altered the composition of the measured chemical properties at both orchards. The values of the soil chemical properties increased cumulatively with compost quantity and time. This trend was consistent at both orchards. Significantly (p<0.05) highest and lowest values of the soil chemical properties were recorded at 15t ha-1 and 0t ha-1 in 2018 respectively but with no significant (p>0.05) differences between 10t ha-1 and 15t ha-1 compost application rates the entire study period. Eucalyptus wood-based compost raised values of the soil chemical properties at ≥10t ha-1 application rates. It is recommended to apply the eucalyptus wood-based compost ≥10t ha-1 at both orchards, nevertheless, other factors governing organic matter decomposition such as soil temperature were not measured hence further studies are necessary.

The role of ectomycorrhization with Scleroderma sp. in promoting substrate nutrients mobilization under phosphorus-enriched compost amendment: A case study with Castanea henryi seedlings

Ecological forestry means continuous and sustainable management of production from the seedling to the adult stage. At present, ectomycorrhizal (ECM) fungi plays an important role in the nutrient management of seedling production in commercial forestry applications. Additionally, phosphorus-enriched compost (PEC) is considered as an environmentally cleaner soil amendment with a great potential in seedling production. However, little is known about the specific antagonistic or synergistic effects of these two sustainable practices on Castanea henryi seedling growth and nutrient uptake. An experiment was conducted to evaluate the effects of ECM inoculation (Scleroderma sp.) and three different application rates (0 %, 15 %, 35 % v:v) of phosphorus-enriched chestnut forest green waste compost (CFG; a typical form of PEC). Results indicated that CFG significantly increased the accumulation of most nutrients in plants but decreased the uptake of Cu and Zn. Without ECM inoculation, there was a significant positive correlation between soil rhizosphere bioavailable P content and aboveground seedling biomass (F = 111.570, p < 0.01). Inoculation of Scleroderma sp. significantly stimulated P mobilization in the soil rhizosphere of the low fertilization treatment (15 %) but had limited benefit in the non-fertilization (0 %) or high fertilization (35 %) treatments. The structural equation modeling indicated that the increase in activity of the rhizosphere soil acid phosphatase was the primary factor that increased soil P bioavailability and plant photosynthetic capacity in the inoculated treatments. Our results better explain the interaction of ECM on PEC sources of nutrients, and provide a low-cost and sustainable commercial propagation system underpinned by biologically regulated nutrient supply systems.

Greenhouse gas emissions from agricultural soil amended with kitchen compost of varying ages

ABSTRACT Although the use of kitchen waste compost is very common, GHG emissions from soil amended with kitchen waste compost have not been studied. This study aimed to determine the effects of kitchen compost age and application rates on GHG emissions to identify optimal compost management. Soil samples mixed with kitchen waste compost at three different ages: 1 month (1M), 2 months (2M), and 3 months (3M) at two application rates (1% and 2% w/w) were incubated at 25°C for 28 days under aerobic conditions. Emissions of nitrous oxide (N2O), carbon dioxide (CO2), and methane (CH4) were determined on days 3, 7, 14, 21, and 28. Results showed that N2O and CO2 emissions decreased with compost age (p < 0.05). Increased application rates of compost led to increased CO2 emissions and suppression of N2O emissions. Furthermore, CH4 was emitted from soil amended with kitchen compost even under aerobic conditions. This study suggests that 3M kitchen waste compost is optimal in terms of GHG emissions upon application to soil under aerobic conditions.

Long-term application of organic compost is the primary contributor to microplastic pollution of soils in a wheat–maize rotation

Microplastics (MPs) are posing new threats to soil ecosystems. Organic fertilizers are considered as an emerging contributor to MPs accumulation in agricultural soils. However, few studies have focused on the MPs fate in soils under long-term organic fertilizer application. Based on an 11-year field test with wheat-maize cropping rotation, this study investigated the characteristics of MPs in pig manure and cow manure composts, and examined the impact of long-term compost application on soil MPs accumulation, surface morphology, and distribution. The MPs contents in pig manure and cow manure composts were 3547 and 4520 items kg−1, respectively. Microplastics abundances in soils under long-term use of these two composts were 144 to 287 and 140 to 316 items kg−1, respectively, which increased significantly with increasing compost application amount and was substantially higher than that in soils without compost. Accumulated soil MPs sourced from long-term compost application were 1.73 × 108 to 7.22 × 108 items ha−1, accounting for 43.0 %–75.9 % of the total, and the contribution value doubled as the compost application rate doubled. The proportion of MPs <1 mm in composts (31.0 %) was lower when compared with that in compost-amended soils (43.8 %), and size and abundance reduced with increasing soil depth. Microplastics shapes and polymer types in composts and compost-amended soils were similar and mostly included fragments of polyethylene and polypropylene and fibers of polyethylene terephthalate. Microplastics in compost-amended soils showed complicated weathered surface morphologies, and soil mineral colloids were attached. These results demonstrate that compost-derived MPs in soils can be gradually weathered and degraded into smaller particles under long-term compost application. These findings provide key insights into the pollution level of soil MPs with organic fertilizer application and serve as a scientific basis for developing MPs mitigation measures in agricultural soils.

Performance of coriander under organic and chemical nutrient management practice

Coriander is one of the most important spice and fresh leaf vegetable which are used widely across the globe. Organic cultivation of this crop has wide scope as it is short duration and reduces the wastage of fertilizers as well as qualitative production. A field experiment was conducted at School of Agricultural Sciences and Forestry, RTU Bangalore in order to know the effective application rate of compost for economic production in comparison to chemical fertilizer. The research data reveals that, application of compost at 10t/ha produced significantly superior growth, yield parameters and herbage yield compared to control. But it was on par with RDF treatment. Thus application of compost at10t/ha might be an effective nutritional input in organic cultivation of coriander.

Influence of compost application rate on nutrient and heavy metal mobility: Implications for stormwater management.

Amending soils with compost has become increasingly common in stormwater management practices. Compost can be a source and sink for nutrients and heavy metals, and it is important to understand the effect of compost on pollutant leaching under different hydrologic conditions. The objectives of this study were (a) to quantify the distribution coefficient (Kd ) of PO4 -P and metals (Cd, Cr, Cu, Ni, Pb, Zn) for compost-soil blends and (b) to examine how compost rate alters leaching patterns of nutrients (NH4 -N, NO3 -N, PO4 -P) and metals from compost-soil blends. Material consisted of a sandy loam subsoil, a yard-waste compost, and compost-soil blends at 20 or 50% compost by volume. Materials were tested in sorption-desorption experiments using simulated stormwater (SW); columns with the materials were also leached with either SW or deionized (DI) water. As compost rate increased, the Kd decreased for PO4 -P and Cr but increased for Cd, Cu, Ni, and Zn. The addition of compost reduced the sorption of PO4 -P and Cr, potentially making it a source of these pollutants. Simulated stormwater did not increase the amount of pollutants retained compared with DI water for compost blends, except for 100% compost columns. Nitrate was the only constituent that had a negative removal efficiency, suggesting the compost was a source of NO3 -N. Column media retained >70% of the metals from the added stormwater solution. These results suggest that yard-waste compost blends at ≤50% have the potential to retain certain pollutants from infiltrating stormwater, but this effect may decline after several storm events.

Effects of Different Organic Amendments on Maize (Zea Mays L.) Growth in Salt Affected Soil

Salinity stress is the most notorious among all abiotic stresses. It hampers the growth and productivity of crops via ionic imbalance, disturbance in the metabolic process and specific ions toxicity. The necessity of time is to introduce better organic amendment rates for its mitigation in cereal crops, especially maize. Therefore, a pot experiment was performed in the wirehouse of the Saline Agriculture Research Centre (SARC), University of Agriculture, Faisalabad to evaluate the effect of farmyard manure and compost application rates in saline soil. A hybrid maize variety (Monsanto DK-6789) was sown and recommended doses of NPK were applied. Organic amendments (FYM and Compost) with their rates (recommended, 25% increased dose of recommended and 50% increased dose of recommended) were applied to assess the growth of hybrid maize with salinity levels (Control &lt; 2dS m-1, moderate salinity_5dS m-1, High salinity_10dS m-1). Seven treatments each with three replicates were carried out by using Complete Randomized Design (CRD). The results of the study indicated that T4 (50% increased farmyard manure) and T7 (50% increased compost) were significantly varied in controlling the shoot and root length, shoot and root fresh weight and dry weight of maize over control at &lt;2, 5 and 10 dS m-1 EC. A significant increase of 32, 28 and 39% in chlorophyll contents of maize validated the efficacious functioning of T4 over control for alleviation of &lt;2, 5 and 10 dS m-1 salinity. Similarly, significant enhancement of 48, 39 and 84% in root fresh weight also declared that T7 was a better treatment under &lt;2, 5 and 10 dSm-1 salinity. In conclusion, T4 and T7 can be used and recommended for better alleviation of salinity stress in maize. More experiments are suggested at the field level by using these 2 application rates of farmyard manure and compost for declaration of modified amendment for salinity stress mitigation.

Determination of the Application Rate of Conventional Compost Integrated with Chemical Fertilizer on Maize (Zia Maize) Yield in Dugda District of East Shoa Zone, Oromia

Integrated soil fertility management is the application of inorganic in combination with organic fertilizer to maintain soil fertility and improve crop yield. A study was conducted in East Shoa Zone, Dugda District on farmers' fields to determine the combined effects of conventional compost as organic fertilizer and NPS as inorganic fertilizer on soil chemical properties and maize production. There were five treatments: Recommended rate of inorganic fertilizer, 100, 75, 50 and 25% equivalent level of compost for nitrogen fertilizer. Recommended level of 69 P2O5/ha were equally applied at all treatments. The experiment was laid out in RCBD design with three replications. The analysis of variance showed no significant differences (P &gt; 0.05) in maize grain yield response. However, the highest maize grain yield (8728.20 kg ha-1) was obtained from treatment two that received 100% equivalent compost for nitrogen fertilizer and the lowest (8325 kg ha-1) was obtained from treatment one where recommended chemical fertilizer alone was applied. Composite Soil samples were also collected before compost application and after harvesting to evaluate the residual effect of compost on soil physiochemical properties. Accordingly, laboratory analysis showed no significance differences (P &gt; 0.05) in total N, available P, soil organic carbon and CEC. However, analysis of variance of post-harvest composite soil samples indicated significant differences on soil available P, OC, TN and CEC as compared to initial soil sample. On the other hand, partial budget analysis was done to determine economically optimum rate of compost integrated with chemical fertilizer. Accordingly, the highest net benefit (126527 Eth. Birr ha-1) was recorded for treatment two where 100% compost (4.6t/ha) plus 150kg/ha NPS fertilizers were applied. The highest marginal rate of return (146) was also obtained from the same treatment. Therefore, the present study showed that combined application of organic and NPS fertilizer enhanced maize productivity and soil fertility status in the study area. Hence combined fertilizer application of 4.6 t ha1 conventional compost integrated with 150 kg ha-1 NPS improved maize productivity and soil chemical properties, and recommended for the study area and similar agro-ecology.

Effects of organic amendment incorporation on maize (Zea mays L.) growth, yield and water-fertilizer productivity under arid conditions

Land degradation is one of the world’s most pressing environmental problems and a constraint to agricultural production. Application of diverse organic amendments provides a management strategy to compensate for soil organic carbon depletion and reduce land degradation. The objective of this study was to investigate the effects of different organic amendments on soil properties, crop growth and water-fertilizer productivity under arid conditions. Soil in a maize field located in the upper reaches of Yellow River was amended with sheep manure compost and maize stover respectively. Five different application rates (2, 4, 6, 8 and 10 t ha-1) were carried out for the compost, and maize stover (6 t ha-1) combined with two different decomposing agents were implemented. Main component of the decomposing agent was Bacillus subtilis and Trichoderma harzianum, respectively. Soil aggregation and physical-chemical properties were generally improved with the incorporation of compost and maize stover. The addition of compost and maize stover reduced the bulk density and increased the field capacity, soil organic matter, aggregate stability and the saturated hydraulic conductivity. The emergence rate and maize growth properties improved in the organic materials amended plots. However, soil properties and crop growth non-monotonically varied with application rate of compost. The addition of different decomposing agents in maize stover amended plots did not show significant impact on most soil properties, but improved soil nutrient status, crop growth and yield with different levels compared with maize stover alone. Comprehensive analysis of yield, crop water productivity and partial factor productivity for nitrogen, incorporation of compost at a rate of 5–6 t ha-1 or 6 t ha-1 maize stover combined with Bacillus subtilis was recommended as a proper strategy in loamy soil under arid conditions.

Short-Term Effects of Increasing Compost Application Rates on Soil C and Greenhouse Gas (N2o and Co2) Emissions in a California Central Coast Vineyard

Short-Term Effects of Increasing Compost Application Rates on Soil C and Greenhouse Gas (N2o and Co2) Emissions in a California Central Coast Vineyard

Reclaiming Eroded Soil Using Sawdust – Poultry Compost for Agricultural production

The removal of top soil withhigh organic matter content is a critical threatto soil functions in most tropical agricultural lands and compost can be utilized in build up of organic carbon stocks and the soil nutrient. A two-year experiment wasconducted to evaluate the effect of different rates of compost application on soil properties, yield and nutrient uptake of maize in an eroded soil. The treatments: control, 5, 10, 15 and 20tonnes per hectares (t ha-1)were laid out inCompletelyRandomizedDesign (CRD) and replicated thriceanddata collected were statistically analysed.The soil was acidic and sandyin texture, the application of compost reduced the acidity and significantly (p &lt;0.05) increased organicmatter and nutrient contentof the soil. Maize grain yield of 3.08and 2.56 t ha-1were obtained in 2015 and in residualexperiment of 2016 respectively with the application of 20 t ha-1of compost. In conclusion, the application of 20t ha-1of sawdust –poultry compost significantly (p &lt;0.05) improvedtheorganic matter and nutrients status of the soil. Also, the yield and nutrient uptake of maize were significantly (p &lt;0.05) higherwith the application of 20 t ha-1of compost