Municipal Solid Waste Compost Research Articles

Synergistic Benefits of Combined Application of Manures and Chemical Fertilizers: Enhancing Growth and Yield of Rice and Wheat

The incorporation of compost and manure with chemical fertilizer has become a key concern to sustain soil fertility. Because the nutrients are continuously depleting from the soil and consequently creating a risk to preserving soil health. Aims: This study assesses the response of different doses of cowdung (CD), municipal solid waste compost (MSWC), oil cake (OC), and poultry manure (PM), incorporated with fertilizers on the growth, yield and protein content of BRRI dhan49 rice and BARI Gom-24. Study Design:  RCBD with 8 treatments and 3 replications. Place and Duration of Study: Field experiment and nutrient analysis were carried out at Bangladesh Agricultural University (BAU), Mymensingh. Wheat was grown during the rabi season from October 2018 to March 2019. Again, rice was cultivated during kharif II season from August 2019 to December 2019 on the same field. Then the laboratory analysis was performed till June 2020. Methodology: Eight treatments i.e., T0 Control (no fertilizer), T1 Recommended Fertilizer Dose, T2 (CD + NPK), T3 (MSWC + NPK), T4 (OC + NPK), T5 (PM + N), T6 (MSWC + N), T7: (CD + OC) were accommodated. Data on the growth parameters including grain and straw yields were documented after the harvest of the fully matured crop simultaneously determining the nitrogen (N) and protein content. Results: Adoption of various combinations of compost and manures with fertilizer accorded an increase in yield contributing characters as well as the N and protein content. Integrating MSWC @ 10 t ha-1+N projected the highest grain yield (7.11 t ha-1 in rice; 4.84 t ha-1 in wheat) and straw yield (8.8 t ha-1 in rice; 5.55 t ha-1 in wheat). It also promisingly secured the highest protein content compared to all other treatments. Conclusion: The appliance of MSWC @ 10 t ha-1 with the recommended dose of N may be endorsed for rice and wheat cultivation in the AEZ-9 region and retaining the physicochemical properties of Old Brahmaputra Floodplain soils.

Microplastic Abundance in the Locally Produced Commercial Compost and the Characteristics

Compost is a widely used soil amendment in the agricultural sector in Sri Lanka. Applying compost could improve soil quality, and it is used in reclaiming degraded agricultural lands. However, low grade compost that contains pollutants may have adverse effects on the quality of the agro-ecosystem. Microplastic is a possible contaminant that can be moved into the agro-ecosystem through poor quality compost application. The present study was conducted to assess the microplastic availability and characteristics of locally produced municipal solid waste and agricultural waste compost. Representing commercial scale agricultural and municipal solid waste composting facilities; twenty compost samples with three replicates were obtained for microplastic identification. A combination of methods (manual separation, oxidation digestion plus density separation) was used to separate and detect microplastics from compost samples. This study revealed that; microplastics are present in agricultural and municipal solid waste compost. Municipal solid waste compost contained significantly (p<0.05) higher microplastic than agricultural waste compost (on average 0.63% and 0.033%, respectively). Average amount of soft plastic content in municipal solid waste compost and agricultural waste compost (1321 items/kg and 71 items/kg, respectively) were higher than the hard plastics (388 items/kg and 37 items/kg, respectively). The study confirmed that compost could act as a carrier of microplastics in agricultural ecosystems. It can be recommended that quality standards should be implemented to minimize the microplastic content in compost and the code of practices for municipal solid waste compost production should be updated to control microplastic contamination to safeguard the quality of agro-ecosystems.

Effects of Biochar and Municipal Solid Waste Compost on Soil Physical Quality and Productivity Index Under Sorghum Cultivation Irrigated with Saline Water

ABSTRACT Amending soil with different materials is gaining acceptance as an effective and inexpensive technique for reclamation of salt-affected soils. The main idea of this study was to investigate the effects of biochar, compost of municipal solid waste and different water salinities level on soil physical quality (SDexter) and soil productivity index (SPI). The treatments were as followed: Control: Soil without biochar or compost and irrigated with tap water, S1: Soil without biochar or compost and irrigated with saline water (EC = 4.5 dS m−1), S2: Soil without biochar or compost and irrigated with saline water (EC = 9 dS m−1), B: Soil amended with 1.5%w/w biochar and irrigated with tap water, B+S1: Soil amended with 1.5%w/w biochar and irrigated with saline water (EC = 4.5 dS m−1), B+S2: Soil amended with 1.5%w/w biochar and irrigated with saline water (EC = 9 dS m−1), C: Soil amended with 1.5%w/w compost and irrigated with tap water, C+S1: Soil amended with 1.5%w/w compost and irrigated with saline water (EC = 4.5 dS m−1), C+S2: Soil amended with 1.5%w/w compost and irrigated with saline water (EC = 9 dS m−1). Soil water characteristic curve (SWCC), Field capacity (FC), Plant wilting point (PWP), Plant available water (PAW), Dexter’s index of soil physical quality (SDexter) and SPI were examined in a greenhouse experiment. The SPI was calculated by integrating the effects of six soil quality indices: plant available water, organic matter (OM), Electrical conductivity (EC), pH, Bulk density (BD) and Root weighting factor (RF) for all treatments were calculated. The results showed that the B treatment had a slightly higher effect on SWCC. The applied B and C treatments caused insignificant increase in PAW relative to the control. In addition, application of biochar or compost to soil significantly increased the SDexter. The application of C treatment had insignificantly higher value of SDexter compared to other treatments. Compared with the control, SPI was significantly higher for the B and C treatments. Overall, the application of biochar/compost minimized the destructive effects of saline irrigation water and improved the quality of the salt-affected fine-textured soil.

Review of the Responses of Various Soil Amendments in Sandy Soils

The primary constraints with sandy soils are low soil organic matter content, poor nutrient availability, heavy losses of applied nutrients and lower water holding capacity. Improving the productivity of sandy soils, particularly in developing countries, could be a viable solution to food insecurity and poverty. Large extent of sandy soil is one of the major constraints for crop production in the Eastern Province of Sri Lanka. Meanwhile, various soil amendments can be applied to improve the performances of cropping systems in sandy soils. Nevertheless, a comprehensive knowledge on which soil amendment would work better across different scales is not well known. To address this knowledge gap, this review was conducted using published literature. Systematic review approach was adopted, and the data were extracted from 65 highly relevant papers. The data were analyzed to calculate the percentage changes on crop yields, soil organic matter and soil carbon, in response to the applications of different soil amendments. The review highlighted the potential of several soil amendments to improve the crop performances in sandy soils. Interestingly, rice straw biochar and the municipal solid waste compost have greatly increased crop yields especially in rice at the rate of 0.9% w/w and 3% w/w in soil weight basis, respectively. Highest improvement in soil organic matter and soil carbon was observed under the applications of compost and spent grain, respectively. Therefore, rice straw biochar and compost could be evaluated to improve the productivity of sandy soils, especially in the Eastern region of Sri Lanka. Although the spent grain was promising, the availability for large scale applications may be limited in Sri Lanka. Testing of these soil amendments would require long-term experiments incorporating different crops and cropping systems. 
 Keywords: Compost, Biochar, Sandy soil, Soil amendments 

The Impact of Integrated Nutrient Management on Trifolium alexandrinum Varietal Performance in the Indo-Gangetic Plains: A Comparative Yield and Economic Analysis

The importance of selecting an appropriate berseem variety and implementing effective nutrient management practices is crucial for maximizing both the production and economic potential of forage crops. This was clearly demonstrated in a field experiment conducted during the rabi seasons of 2019–2020 and 2020–2021. The experimental setup was a factorial randomized block design incorporating five berseem varieties (Mescavi, HB-1, HB-2, BL-10, and BL-42) and five integrated nutrient management practices: 100% recommended dose of fertilizers (RDF) or NM-1, 75% RDF + plant growth-promoting rhizobacteria (PGPR) or NM-2, 75% RDF + municipal solid waste compost (MSWC) or NM-3, 75% RDF + farmyard manure (FYM) + PGPR or NM-4, and 50% RDF + MSWC + PGPR or NM-5. The objective of the experiment was to evaluate the physio-morphological responses, biomass yield, and economic efficiencies of different berseem varieties under various nutrient management practices. The experimental results highlighted the superior performance of the BL-42 variety in terms of growth and yield attributes compared to the other tested berseem varieties. Specifically, BL-42 showed an enhancement in total green fodder yield by 17.10%, 26.60%, 37.75%, and 28.04% over the varieties BL-10, HB-2, HB-1, and Mescavi, respectively. Moreover, the application of the 75% RDF + FYM + PGPR treatment (NM-4) significantly boosted the total green fodder yield by 13.08%, 14.29%, 34.48%, and 39.02% over the 75% RDF + MSWC, 100% RDF, 75% RDF + PGPR, and 50% RDF + MSWC + PGPR treatments, respectively. In terms of economic returns, BL-42 achieved a significantly higher gross return (GR) and net return (NR) of 194,989 ₹/ha and 145,142 ₹/ha, respectively, compared to the GR and NR of BL-10 (166,512 and 116,665 ₹/ha, respectively). Similarly, the nutrient management practice of 75% RDF + FYM + PGPR recorded the highest GR and NR (191,638 and 137,346 ₹/ha, respectively) compared to the 100% RDF treatment (167,593 and 120,716 ₹/ha, respectively). These findings underscore the critical role of variety selection and tailored nutrient management in optimizing both the yield and economic gains in forage crop cultivation. The significant differences in production and returns highlight the potential of targeted agronomic strategies to enhance the profitability and sustainability of forage farming.

Characterization of Leachate and Evaluation of Groundwater Pollution in the Vicinity of the Municipal Solid Waste Landfill in Srinagar, Jammu & Kashmir

Abstract: The most popular way for disposing of municipal solid waste (MSW) throughout India, including Kashmir, is through landfills. However, the discharge of leachate from these facilities has seriously contaminated groundwater. An evaluation was conducted on the groundwater quality near the Srinagar landfill site (Achan). In order to investigate the potential effects of leachate percolation on groundwater quality, samples of leachate and groundwater were taken from the Srinagar dump site and its surrounding areas. Groundwater and leachate samples were used to measure the concentration of various physio-chemical parameters (pH, EC, TDS, COD, BOD, Ca2+, Mg2+, Na+, K+, Cl-, SO42-, NO3-, NH4+, PO43-, Phenol), as well as microbiological parameters (total coliform and faecal coliform) and heavy metals (Cd, Cr, Cu, Fe, Ni, Pb, Zn, and Hg). The relatively elevated levels of NH4+, EC, TDS, BOD, phenol, Cd, and Mg, Cr were above the limits of Indian standard and WHO for drinking water. In addition to this , these also represent heavy pollutant indicators as per the Single Point Pollution Index as well by the Nemero index, as these elements crossed the upper most limit for both these pollution indeces. Assessing the water contamination in depth and distance wise, closer to landfill and shallow wells were characterized as the most polluted and had some additive contaminants ( Cl- ,SO4, Ca , Ni ). This is an indication of pollution transfer and the leachate movement. The presence of total coliform and faecal coliform although in small counts warns for the groundwater quality and thus renders the associated aquifer unreliable for domestic water supply. There is no natural or other possible reason for high concentration of these pollutants, thus it can be concluded that leachate has significant impact on groundwater quality in the area. In the present study, also an attempt has been made to investigate physico-chemical properties, fertilizing potential and heavy metal polluting potentials of the three types of composts including municipal soild waste compost, green waste compost and mixed waste compost. Each of these types were given a treatment with effective micro organisms (EM) to understand the quality of compost so formed by the composting process by its analysis (Laboratory as well as statistical) and the quality of composts was found out using Quality control Indices such as Fertilizing Index and Clean Index. Parameters like, pH, EC, TOC, total nitrogen, total phosphorous, total potassium, C/N ratio, and heavy metals like zinc, copper, cadmium, nickel, lead, and chromium were analyzed and it was found that all the parameters were within the permissible limits prescribed by FCO-2000. Further Fertility Index and Clean Index were determined for the samples and it was found that proper segregation of the solid waste is important from composting point of view because mixed waste affects the quality of compost. From the calculated values for the compost prepared from untreated MSW, FI (3.40) and CI (2.8), for the treated MSW Compost, FI as 3.47 and CI as 3.0, for the untreated mixed waste FI (3.27) and CI (3.0) and for the treated mixed waste FI (3.47), CI (3.2) The determined values indicates that all these compost types belongs to marketable Class D (medium fertilizing potential and medium heavy metal content).The fertility index value was estimated as 2.0 and the Clean Index value as 3.06 for the untreated green waste while for treated green waste FI(2.73) and CI(3.7), which indicates that both compost types belongs to restricted use Class RU-1 (Should not be allowed to market due to low fertilizing potential. However, these can be used as soil conditioner)

Testing biowaste materials as peat replacement in organo-mineral fertilizers

Organo-mineral fertilizers (OMFs) can have higher efficiency than mineral fertilizers. In Europe, peat is commonly used as an organic matrix in OMFs, as it is a highly stable organic material. However, peat extraction releases long-term stored organic C. Stabilized biowaste materials could replace peat in OMFs. Thus, this study aimed to understand how the variety of chemical properties in biowastes can influence OMF-soil interactions and nutrient availability to plants. Peat, green compost (GC), municipal solid waste compost (MSWC), and vermicompost (VC) were used as the organic matrix of OMFs with a C-N-P2O5 content of 7.5, 10, and 5%, respectively. OMFs were tested first in a ten-day plant-free incubation to measure Hedley P fractionation, nitrate, ammonium, total N in the soil, and CO2 and NH3 emissions. Further, a 30-day greenhouse trial measured maize yield and N and P use efficiencies. Controls included no fertilization (N0P0) and mineral N and P fertilization (MFNP). No differences were found in the incubation experiment for mineral N fractions in the soil. Fertilization significantly increased CO2 emissions, which were slightly higher in OMFs over MFNP, whereas OMFs significantly increased ammonia volatilization compared to MFNP. Available P had consistent results in the incubation and the greenhouse trials. Peat and MFNP had the highest water-and bicarbonate-P pools in the first experiment and higher yield and P use efficiency by maize. Therefore, OMFs from biowaste materials exhibited limited suitability for short growth cycles due to lower P use efficiency and higher ammonia volatilization.

Assessment of the Characteristics of the Municipal Solid Waste Compost in Lebanon

Assessment of the Characteristics of the Municipal Solid Waste Compost in Lebanon

Context and prospects for decentralized composting of Municipal Solid Waste in Brazil

Factors such as urbanization contribute to the constant increase in the generation of municipal solid waste, of which the organic fraction is the most significant. Composting is a versatile and scalable alternative for managing organic waste, and European countries have been intensifying the adoption of this strategy, both centrally and decentrally. On the other hand, the management of the Organic Fraction of Municipal Solid Waste (OFMSW) in Brazil, with the exception of unsuccessful experiments with centralized composting systems, is limited to disposal in landfills or dumps, rendering recoverable organic material useless and generating significant emissions of methane, one of the main greenhouse gases. Studies addressing decentralized composting as a strategy to improve waste management are still infrequent in Brazil. In this context, this article aimed to outline an overview of the generation of OFMSW in the world and in Brazil, as well as initiatives for its proper management. Based on a literature review, it compares the management of OFMSW in Europe and Brazil, and points out perspectives from the current Brazilian regulatory framework. Then, it discusses the potential benefits and challenges in implementing and operating decentralized systems. Decentralized composting (community or domestic) is a low-cost alternative for the management of OFMSW, but requires citizen engagement, in addition to attention to the quality of the final products. Future studies should address the positive impacts and possible restrictions of this alternative in Brazilian contexts, contributing to enable its integration into the management models currently adopted in the country.

Municipal solid waste compost use can improve crop barley production and enhance soil chemical fertility

The study aims to point out the effect of municipal solid waste compost (MSWC) and traditional mineral fertilizers use, on rainfed forage barley herbage and grain production, nutritive value, and on soil chemical characteristics. During a three-year field trial, the MSWC treatments were COM1, 20 Mg ha−1 (DM) applied each year; COM2, 20 Mg ha−1 applied only the first year. The mineral fertilization was MIN50 (50 kg ha−1 of N + 46 kg ha−1 of P2O5), and MIN100 (100 kg ha−1 of N + 92 kg ha−1 of P2O5), applied each year. Fertilization treatments were compared with unfertilized control (COM0 and MIN0). Two years out of three COM1 showed a significant higher barley herbage dry matter (HDM) production and CP, when compared to COM0. COM1 in one year increased grain yield (YLD) whereas increased CP all years and decreased starch grain content two years out of three. MSWC strongly increased levels of sodium (Na) in herbage and grain. Mineral fertilizers levels significantly increased HDM production and YLD and their CP content compared to MIN0. Moreover, it lightly decreased herbage NDF, ADF, WSC and Total phenols content, raising in vitro dry matter digestibility (IVDMD). In soil, after three years of fertilization, COM1 increased SOC (Soil Organic Carbon), Total N, available P, exchangeable K and Mg content, but also exchangeable sodium percentage (ESP) and electrical conductivity (EC), showing higher values than COM2 and COM0. Mineral fertilization influenced only the available P soil level, increasing the content compared to MIN0. This paper pointed out that mineral fertilizers had clear short-term effects on the barley growth, yield, and nutritional value, but did not contribute to soil long-term fertility improvement. MSWC increased barley growth and yield reaching similar values obtained with mineral fertilizers. Above all, MSWC showed capability to improve soil fertility mainly in terms of organic matter and macronutrients and its use is consistent with the recent EU regulation on organic fertilizer productions (2018/84) that aims to “maintaining the long-term fertility of soils”.

Assessment of Energy-Efficient Spouted Bed Aerobic Composting Performance for Municipal Solid Waste: Experimental Study

Municipal solid waste contains a high percentage of organic waste, and when it is not disposed of, it becomes a threat to the environment by contaminating the air, water, and soil. Composting is one of the recovery techniques in which the end product of waste eventually contributes to the agriculture industry, reducing the harmful effects on the environment. Composting municipal solid waste is a clean and effective technique for waste disposal. The mechanized composting process is carried out by several methods, like the windrow method or the rotary drum method. However, large-scale composting processes involve energy consumption and labor costs for waste preparation and handling. This increases the market cost of compost. Hence, an energy-efficient composting technique with minimum environmental impact is needed. This research work aims to analyze the performance of an energy-efficient spouted bed technique for aerobic composting of municipal solid waste for the first time using spouted bed technology with sand as the bed material. Spouted bed composting handles the waste using a pneumatic method with minimum power consumption in comparison to conventional mechanical methods with windrow processes or rotary composting machines. The experimental procedure involves a test run of waste along with bed material and the collection of temperature variations, pH variations, moisture variations, and volatile matter content during the progression of the composting process. The results of this experimental study on a single batch of waste are then used to analyze the quality of the compost generated and compare it with existing results. Specific energy consumption for the process was less than 800 kJ/ton of raw waste input, which is much less than the energy used for conventional composting techniques. pH, volatile content, moisture, and temperature measurements indicated agreement with the established parameters of the composting process.

Long-term effect of municipal solid waste compost on the recovery of a potentially toxic element (PTE)-contaminated soil: PTE mobility, distribution and bioaccessibility

  Compost from municipal solid waste (MSWC) can represent a resource for the environmental management of soils contaminated with potentially toxic elements (PTEs), since it can reduce their mobility and improve soil fertility. However, the long-term impact of compost on soil recovery has been poorly investigated. To this end, the influence of a MSWC added at different rates (i.e. 1.5, 3.0 and 4.5% w/w) to a multi-PTE-contaminated (e.g. Sb 412 mg kg−1, Pb 2664 mg kg−1 and Zn 7510 mg kg−1) sub-acidic soil (pH 6.4) was evaluated after 6 years since its addition. The MSWC significantly enhanced soil fertility parameters (i.e. total organic carbon, Olsen P and total N) and reduced the PTE labile fractions. The distribution maps of PTEs detected through µXRF analysis revealed the presence of Zn and Pb carbonates in the amended soils, or the formation of complexes between these PTEs and the functional groups of MSWC. A higher oral, inhalation and dermal bioaccessibility of each PTE was detected in the soil fine-grained fractions (< 2 and 2–10 µm) than in coarse particles (10–20 and 20–50 µm). The MSWC amendment generally did not modify the PTE bioaccessibility, while the relative bioaccessibility of cationic PTEs was greater than that of anionic ones (e.g. Cd > Zn > Pb > Sb > As). Pb and Sb showed the highest hazard quotients (e.g. 2.2 and 10 for Sb and Pb, respectively, in children). Overall, the results indicated that the MSWC used can be an effective option for the recovery of PTE-contaminated soils, even in the long term.

Assessing egg deposition behaviour of female black soldier fly (Hermetia: Illucens) in Kumasi, Ghana using MOSW as bait

The availability of the black soldier fly (BSF) at a location is of great importance if its larvae are to be used for commercial composting of municipal organic solid waste (MOSW). In this context, it is crucial to determine where the insects are readily available and how natural environmental conditions influence their oviposition. This study used MOSW as bait to determine locations where these insects are readily available and their egg cluster as an indication of their presence. Data were collected at four locations: Plantain farm, poultry farm, under a pear tree, and waste communal container site. For each site, data were collected in the morning (6:00 a.m.–12:00 p.m.), afternoon (12:00 p.m.–6:00 p.m.), and evening (after 6:00 p.m.) to determine the peak egg-laying times of these insects. This was carried out for two seasons of the year – rainy season (June, July and August) and dry season (December, January, and February) to assess seasonal variability on oviposition and fecundity. Environmental conditions such as temperature, relative humidity, and light intensity were also measured under which oviposition took place. The highest average number of BSF egg clusters of 17.5 ± 13.74 was harvested at the waste communal container site and the lowest average number of 2 ± 0.81 was harvested at the poultry farm. Peak egg laying times were recorded in the afternoon between 12:00 p.m. and 6:00 p.m., where an average of 15.17 ± 4.7 clusters were harvested. Most BSF egg clusters were harvested during the rainy season, averaging 9.1 ± 12.2. The dry season recorded a higher average number of eggs per cluster at 454.18 ± 164.92. It is concluded that BSF larval composting technology can be commercialized in Kumasi, Ghana as the insects were readily available during the two main seasons in the country.

Distribution of soil organic carbon between particulate and mineral-associated fractions as affected by biochar and its co-application with other amendments

The application of biochar to soils, either alone or combined with other amendments, represents a management practice aimed at storing carbon (C) while enhancing soil fertility. However, the long-term effects of biochar application on soil organic C protection against microbial decomposition are uncertain. This study investigated, in a 9-year-long-term field experiment, the protection of organic C by minerals and iron (Fe) in soils amended with biochar alone or combined with either municipal solid waste compost or sewage sludge. Particulate (not protected by minerals) and mineral-associated organic matter fractions were separated, quantified, and finally the Fe-mediated protection mechanisms were examined by Fe K-edge extended X-ray absorption fine structure spectroscopy. With respect to the unamended control soil, soils amended with biochar, especially when combined with municipal solid waste compost and sewage sludge, had 3 times greater content of particulate organic C. Biochar combined with municipal solid waste compost and sewage sludge also increased mineral-associated organic C content (1.5×), although the magnitude of the effect was smaller than for the particulate organic C fraction. The contents of Fe(III)-organic matter complexes in particulate and mineral-associated organic matter fractions of the amended soils were similar to those of the unamended soils. Hematite represented the main Fe oxide phase in the particulate organic matter fraction of all the soils as well as in the mineral-associated organic matter fraction of the unamended soils, whereas ferrihydrite was more abundant in the mineral-associated organic matter fraction of the amended soils. As a whole, the obtained results in general, and the positive effect on the mineral-associated organic matter possibly mediated by ferrihydrite occurrence in particular, highlight the potential of biochar, alone or in combination with other amendments, as a strategy to store and preserve C in soils.

Pyrolysis of municipal solid waste compost: Pilot plant evaluation as a sustainable practise of waste management.

To evaluate the potential of compost based on municipal solid waste (MSW) and 20% legume pruning under a pyrolysis process, generated products, including solids (biochar), liquids (bio-oil), and gases (non-condensable gases), through experimentation in a pilot plant with a fluidized bed reactor at 450°C and gas chromatography/mass spectrometry have been analysed. In addition, the compost kinetic behaviour by thermogravimetric analysis (TGA), using the Flynn-Wall-Ozawa (FWO) method, has been investigated. Four different reaction zones, associated with lignocellulosic materials (hemicellulose, cellulose, and lignin) with a first step for water evaporation, in TGA curve have been observed. A biochar with low stability and aromaticity, considering high and low O/C and H/C ratios, respectively, has been obtained. The obtained pyrolytic liquids contain a high concentration of phenolic compounds because of a significant presence of lignins and other high molecular weight compounds in the original material. Moreover, the generated non-condensable gases consist mainly of short-chain compounds, such as alcohols, aldehydes, and alkenes produced from hemicellulose, cellulose, and proteins.

Differential Effects of Organic Inputs on Soil Fertility and Growth of Tea Plants

The objective of the experiment was to evaluate how newly planted biclonal Tocklai stock tea varieties (TS 462, TS 463, TS 520, and TS 589) respond to compost in a series of treatment including control (without application), cow dung, vermicompost, municipal solid waste compost, and homemade kitchen waste compost applications. A total of 20 tea plants (5 plants of each tea variety) were planted in plastic buckets of equal size (16 litres). 300 gm. of compost was applied to each plant continuously at an interval of 25 to 30 days for the initial six months, and then compost application was discontinued for the next six months. Data were collected before, during, and after compost application. The highest growth in plant height (11cm to 51 cm), number of leaves (33 to 95), and number of branches (8 to 15) were recorded in the tea plants of the TS 463 variety. The pH of soil samples was found in the range of 4.72 to 6.61. The pH level of the acidic soil was slightly increased by the compost application. The average SOM% ranged from 6.88% to 11.94%, and it was found that a good SOM% was supportive of the good growth of the tea crop. N% was found between 0.85% and 0.217%, and P levels were found between 18 ppm and 50 ppm. The suitable N% and P levels affect plant growth most significantly in terms of the number of leaves and the number of stems. SOM% was found to be highest in vermicompost-treated soil, N% and P levels were optimal in home-made kitchen waste compost, and K levels were highest in cow dung-treated soil. Therefore, it can be concluded that an integrated compost application can be recommended for ideal growth and good plant health status for sustainable tea production.

Impact of P Enriched Compost on Growth and Yield Attributes of Barnyard Millet in Red and Black Soils of Madurai District, India

A field study was conducted during the summer (kharif) season of 2023 at the Lalapuram village, Thirumangalam block of Madurai district, to assess the influence of phosphorus-enriched compost on the growth and yield parameters of barnyard millet in both red and black soils. The recommend dose of barnyard millet was 40: 20: 0 kg ha -1 of NPK in which the recommended dose of P (20 kg ha -1) was given in form of enriched compost and the enrichment was done at 1: 10 ratio of P source and compost. Three different types of compost such as farmyard manure compost, municipal solid waste compost and vermicompost were enriched with two different P sources such as single super phosphate @ 100 kg / t of compost and rock phosphate @ 100 kg / t of compost. Azophos, a plant growth promoting rhizobacteria based microbial consortium was added to the P enriched compost @ 2 kg / ton of compost.  Among the different combinations, application of SSP enriched vermicompost @ 750 kg ha -1 along with microbial consortium performed better in both the soils. The growth and yield attributes of barnyard millet in black soil was better compared to that of red soil. SSP enriched vermicompost @ 750 kg ha -1 along with microbial consortium recorded the highest growth parameters in terms of no. of tillers per plant (8.71), Leaf area index ( 2.98 ), root length  ( 20.7 cm) and dry matter production (5260.1 kg ha -1) at 60 DAS and yield parameters in terms of no of productive tillers (6.81), panicle length (21.4 cm), panicle weight (14.65 g), 1000 grain weight (3.24 g), grain yield (2350 kg ha -1) and stover yield (4420 kg ha -1). Hence, it was found that the application of SSP-enriched vermicompost coupled with azophos at 30 and 60 DAS of the crop growth stages, can curtail N and P fertilizer consumption by 50 and 100 percent respectively while fostering sustainable plant growth and enhancement of yield.

Towards Sustainable Composting of Source-Separated Biodegradable Municipal Solid Waste—Insights from Long An Province, Vietnam

Inadequate municipal solid waste (MSW) management has become a pressing concern, resulting in significant environmental contamination, particularly in developing countries. Composting has demonstrated its practicality and feasibility for addressing this issue; however, the lack of at-source solid waste separation remains a major challenge. As a result, in this study, the first sustainable MSW separation at source was conducted in Tan An City, Long An Province. The objective of this study was to evaluate the compost process and quality using Tan An City’s separated biodegradable organic solid waste as the raw material, through a windrow composting process with active aeration. Biodegradable organic waste, slow-biodegradable organic waste and plastic waste accounted for 84.5%, 15.1% and 0.4%, respectively, of the total waste. The pH, moisture, volatile solid percentage, total nitrogen, total organic carbon and carbon-to-nitrogen ratio of the separated solid waste were 8.7 ± 0.4, 76.8 ± 1.9%, 68.3 ± 1.3%, 2.1 ± 0.1%, 35.7 ± 2.2% and 17 ± 0.8, respectively. Rice straw was mixed with solid waste as a bulking material in a 31%:69% ratio to achieve a moisture content of 55% in the mixture. After 10 weeks, an evaluation of the compost’s quality revealed its potential suitability for agricultural applications. Notably, Salmonella was not detected in the compost, and the heavy metal levels were below standard limits, indicating the safety of the compost. To ensure optimal nutrient levels for effective plant growth, a slight nitrogen and phosphorus supplement was recommended. Aligned with the C/N ratio of 12.1 and a consistent temperature of approximately 29 °C, this indicates a high degree of maturity and stability in the composting process. The framework of this study demonstrates the effectiveness of at-source MSW separation in paving a sustainable path for MSW management.

Rationalizing mineral gypsum use through microbially enriched municipal solid waste compost for amelioration and regaining productivity potential of degraded alkali soils

Reclamation of alkali soils to harness their productivity potential is more complex due to the presence of excess sodium ions, poor hydraulic conductivity and infiltration rate, resulting in poor plant growth and crop productivity. Sodic soil reclamation using inorganic ameliorants like mineral gypsum or phosphogypsum is beyond the reach of small and marginal farmers having alkali soils because of their higher market prices and shortage of availability. Conjoint use of inorganic and organic amendments can be a pragmatic solution for improving soil physico-chemical and biological properties and sustaining crop productivity. Municipal solid waste compost (MSWC) available in abundant quantity if enriched with the efficient halophilic microbial consortium and used in conjunction with a reduced dose of gypsum can be a cost-effective approach for sustainable reclamation of alkali soils and harnessing their productivity potential. Hence, a field experiment was conducted on a high alkali soil (pH2 9.2 ± 0.10), electrical conductivity (EC) 1.14 ±  0.12 dS m−1, exchangeable sodium percentage 48 ± 2.50 and organic carbon (0.30%) was conducted during 2018–19 to 2020–21 to study the combined effect inorganic and organic (enriched municipal solid waste compost (EMSWC)) amendments on amelioration of alkali soils and sustaining productivity of rice–wheat cropping system. Application of gypsum @ 25% GR + enriched MSW compost @ 10 t ha−1 (T6) showed significant improvement in soil physico-chemical and biological properties over the sole application of organic (T3 and T4), inorganic (T2) and control (T1). A significant improvement in soil fertility status in terms of available nitrogen and micronutrients as well as CO3, HCO3, Cl, Ca and Mg content were recorded with the combined application of organic and inorganic soil amendments (T5 and T6) over the sole application of mineral gypsum. Soil microbial biomass carbon (MBC), nitrogen (MBN) and phosphorus (MBP) improved significantly due to the application of EMSWC with gypsum over the application of gypsum only. Grain yield of rice and wheat increased significantly (P < 0.05) owing to the application of a reduced dose of gypsum (25% GR) and EMSWC @ 10 t ha−1 (T6) with values of 5.55 and 3.83 t ha−1, respectively over rest of the treatments. Three years economic analysis of the study revealed that treatments T6 and T5 gave the highest positive net return whereas it was lowest in treatment T1 and negative in treatment T2. The highest benefit-to-cost ratio (B:C) was obtained in treatments T6 and T5 which were significantly higher compared to the rest of the treatments.

Municipal solid waste compost: a comprehensive bibliometric data-driven review of 50years of research and identification of future research themes.

This paper offers a thorough bibliometric review of the literature on municipal solid waste compost (MSWC), focusing on the past two decades. Using an extensive dataset of 827 documents, the research patterns are analyzed via the R-based Bibliometrix package, merging metadata from Web of Science and Scopus. The analysis reveals substantial global growth in MSWC research, with a particular surge in the last 20years. Discipline-specific journals are the main publishers, while multidisciplinary environmental outlets gained more citations. The study identifies five major collaborative author clusters that dominate productivity and citation frequency. The thematic evolution over the past five decades shows a transition from waste disposal towards topics such as heavy metals, soil properties, and plant nutrition, with emerging themes like carbon sequestration, biochar, and microplastics signaling future research directions. Specifically, the field has experienced a 7.86% annual growth rate, with an average citation rate of 26.88 per article. The 827 publications emerged from 317 sources and 1910 authors, with an international co-authorship rate of 14.75%, reflecting the field's interdisciplinary character. Thirteen primary sources and twenty-two key authors were identified as major contributors. On the geographical front, Spain and Italy led with the most contributions and highest citation count, respectively. In terms of keywords, "heavy metals" and "sewage sludge" were the most recurrent, indicating the prevailing topics in MSWC research. This analysis hence provides key insights into the evolution and future trajectory of MSWC studies.