Bio-Compost Behaviour as Soil Additive by Food Waste Pretreatment on the Growth of Abelmoschus esculentus L.: A Systematic Review

Food waste (FW) has always been a significant issue faced by almost all countries worldwide. The rise in FW does not only influence one’s food supply, yet the greenhouse gas (GHG) emission such as methane (CH4) and carbon dioxide (CO2) gas leads to global warming and health issues. This paper reviews the primary FW treatments available in all countries. Most advanced countries have accomplished that the least cost and most efficient FW treatment is composting. Among all the composting methods available, vermicomposting (VC) that uses redworms (Eisenia fetida) produces nutrients rich bio-compost, as proven in the existing literature. Furthermore, bio-compost produced by the VC method nourishes plant growth. In this study, the primary research data sources are 78 scientific articles over the last few years. This research is the consensus on VC as the FW treatment. Besides, briefly discuss the FW pretreatment methods, the effect of bio-compost on soil properties, and their corresponding effects on the growth of Abelmoschus esculentus L.

Use of Vermicompost from Sugar Beet Pulp in Cultivation of Peas (Pisum sativum L.)

A properly conducted vermicomposting process is an environmentally friendly technology used to transform selected organic waste into vermicompost. This organic fertilizer is increasingly used in agriculture and horticulture as an alternative to mineral fertilizers. Research has investigated the use of vermicompost made from the waste mass of sugar beet pulp as a soil additive in the cultivation of peas (Pisum sativum L.). Experimentally, five treatments consisted of: a heavy clay soil as control (SL); the same soil with 10, 25, and 50% substitution of vermicompost, (V10, V25, and V50, respectively); and a standard peat-based horticulture substrate (GS) for comparison. Analyzed pea characteristics and the content of macro and microelements in their biomass were most favorably influenced by 25 and 50% vermicompost addition, and the values obtained were similar to those in the GS treatment. The lowest values of analyzed traits for P. sativum were found in the SL group. Thus, appropriate addition of vermicompost in the construction of plant growing substrates can reduce the use of inorganic fertilizers and be an alternative to peat in the medium, contributing to reduced use of this valuable environmental resource.

Potencies of Justicia adhatoda L. for its possible phytotoxic activity

The phytotoxic effects of Justicia adhatoda L. were investigated on cauliflower, broccoli, tomato, foxtail millet and barnyard grass. The experiments were carried out under laboratory and in pot experiments. Six different aqueous methanol extract concentrations (control, 0.001, 0.003, 0.01, 0.03 and 0.1 g DW equivalent mL-1 extract) were tested in the laboratory and six aqueous extract concentrations (control, 1.0, 2.0, 3.0, 4.0 and 5.0 g DW mL-1 extract equivalent) were evaluated in the pot experiment. Results showed a reduction in germination and growth (shoot length, root length and biomass weight) at higher extract concentration compared to control. The leaf extracts from J. adhatoda showed that the foxtail millet and barnyard grass are germinating below 50 % both in the laboratory condition and in the pot experiment at their maximum concentration. When maximum extracts have been applied, we have found less than 0.5 cm of shoot and root of foxtail millet and barnyard grass. Maximum dry weight reduction was observed in foxtail millet and barnyard grass at the same concentration. The findings show that J. adhatoda may have phytotoxic potential and thus contains phytotoxins. Therefore, J. adhatoda can be used in sustainable crop production as a mulch or soil additive to suppress weeds.

Production of Biochar from Biomass

Biochar is a kind of charcoal that’s produced from biomass using pyrolysis technology. As climate change continues to be a growing concern, biochar has been sought for its environmental applications. It is both cost effective and environmentally sound in terms of being a soil additive and renewable fuel. When used as a soil amendment, biochar has been shown to improve water holding capacity and absorb more nutrients. Biochar also sequesters carbon dioxide when applied to soil, and can also be used as a replacement for activated carbon that is prepared from coal. The objectives of this research was to produce biochar from biomass and study biochar’s properties. A thermogravimetric analysis (TGA) was used to measure the weight loss behavior of the wood sample (biomass) as the temperature increased. The biomass was heated to 500 °C in a nitrogen atmosphere and then cooled in nitrogen to prevent combustion of biochar. The overall yield of biochar was 15%. Elemental analysis of biomass shows the composition of the sample to be mostly carbon and oxygen with fewer amounts of hydrogen and nitrogen. Surface area of the prepared biochar was 305 m2/g, which is approximately 100 times the surface area of raw biomass. Biochar’s higher porosity will allow for greater absorption of nutrients when applied to soil.

The role of biochars in sustainable crop production and soil resiliency

Biochar is a promising soil additive for use in support of sustainable crop production. However, the high level of heterogeneity in biochar properties and the variations in soil composition present significant challenges to the successful uptake of biochar technologies in diverse agricultural soils. An improved understanding of the mechanisms that contribute to biochar–soil interactions is required to address issues related to climate change and cultivation practices. This review summarizes biochar modification approaches (physical, chemical, and biochar-based organic composites) and discusses the potential role of biochar in sustainable crop production and soil resiliency, including the degradation of soil organic matter, the improvement of soil quality, and reductions in greenhouse gas emissions. Biochar design is crucial to successful soil remediation, particularly with regard to issues arising from soil structure and composition related to crop production. Given the wide variety of feedstocks for biochar production and the resultant high surface heterogeneity, greater efforts are required to optimize biochar surface functionality and porosity through appropriate modifications. The design and establishment of these approaches and methods are essential for the future utilization of biochar as an effective soil additive to promote sustainable crop production.

Biochar and Biomass Ash as a Soil Ameliorant: The Effect on Selected Soil Properties and Yield of Giant Miscanthus (Miscanthus x giganteus)

We assess the possibility of using biochar and ash from plant biomass to fertilise giant miscanthus (Miscanthus x giganteus). The paper concerns the optimisation of the combination of fertiliser applications of the aforementioned materials in the context of the plant yield obtained. There was an increase in yield of 8–68% over the two years of research when compared with the control plots. It was found that the application of biochar, ash from biomass and a combination of the two at appropriate rates as a soil additive can substitute for classic mineral fertilisers and strengthen the ecological aspects of energy crop cultivation. The interpretation of the results obtained enabled the selection of optimum fertiliser applications, resulting in a significant increase in the yield of plants and an improvement in soil chemical properties. It was found that the highest yield of dry matter of giant miscanthus plants, after both the first and second year of cultivation, was obtained by applying the fertiliser containing ash at a rate of 1.5 t ha−1, together with biocarbon and the combination of biochar and ash at a rate of 1.5 t ha−1.

Capillary rise experiment to assess effectiveness of an enzyme soil stabilizer

An experimental program to assess of the attributes of an enzyme soil stabilizer is described. The focus of the program was two 1 year capillary rise experiments designed to test the influence of the soil additive on the soil’s adsorption of water. The enzyme additive is typically applied to marginal clay-based soils to improve the performance of road subgrades. The study investigated the potential increase in shear strength and the reduction in swelling. The two long-term soil column tests were conducted to measure water absorption due to capillary rise for soil specimens with, and without, enzyme treatment. The test results demonstrated that the addition of the enzyme soil additive had the effect of reducing water retained in the pore spaces of a partially saturated soil. The soil treated with the enzyme additive absorbed a lower quantity of water in the capillary rise test, and at a slower rate of absorption. The results from a concurrent suite of tests suggested that partially saturated clay having lower moisture content was linked to an increase in shear strength.