From waste to food : optimising the breakdown of oil palm waste to provide substrate for insects farmed as animal feed

Waste biomass from the palm oil industry is currently burned as a means of disposal and solutions are required to reduce the environmental impact. Whilst some waste biomass can be recycled to provide green energy such as biogas, this investigation aimed to optimise experimental conditions for recycling palm waste into substrate for insects, farmed as a sustainable high-protein animal feed. NMR spectroscopy and LC-HRMS were used to analyse the composition of palm empty fruit bunches (EFB) under experimental conditions optimised to produce nutritious substrate rather than biogas. Statistical pattern recognition techniques were used to investigate differences in composition for various combinations of pre-processing and anaerobic digestion (AD) methods. Pre-processing methods included steaming, pressure cooking, composting, microwaving, and breaking down the EFB using ionic liquids. AD conditions which were modified in combination with pre-processing methods were ratios of EFB:digestate and pH. Results show that the selection of pre-processing method affects the breakdown of the palm waste and subsequently the substrate composition and biogas production. Although large-scale insect feeding trials will be required to determine nutritional content, we found that conditions can be optimised to recycle palm waste for the production of substrate for insect rearing. Pre-processing EFB using ionic liquid before AD at pH6 with a 2:1 digestate:EFB ratio were found to be the best combination of experimental conditions

Phytoremediation of Heavy Metals: An Indispensable Contrivance in Green Remediation Technology

Environmental contamination is triggered by various anthropogenic activities, such as using pesticides, toxic chemicals, industrial effluents, and metals. Pollution not only affects both lotic and lentic environments but also terrestrial habitats, substantially endangering plants, animals, and human wellbeing. The traditional techniques used to eradicate the pollutants from soil and water are considered expensive, environmentally harmful and, typically, inefficacious. Thus, to abate the detrimental consequences of heavy metals, phytoremediation is one of the sustainable options for pollution remediation. The process involved is simple, effective, and economically efficient with large-scale extensive applicability. This green technology and its byproducts have several other essential utilities. Phytoremediation, in principle, utilizes solar energy and has an extraordinary perspective for abating and assembling heavy metals. The technique of phytoremediation has developed in contemporary times as an efficient method and its success depends on plant species selection. Here in this synthesis, we are presenting a scoping review of phytoremediation, its basic principles, techniques, and potential anticipated prospects. Furthermore, a detailed overview pertaining to biochemical aspects, progression of genetic engineering, and the exertion of macrophytes in phytoremediation has been provided. Such a promising technique is economically effective as well as eco-friendly, decontaminating and remediating the pollutants from the biosphere

Production of Nutrient-Enriched Vermicompost from Aquatic Macrophytes Supplemented with Kitchen Waste: Assessment of Nutrient Changes, Phytotoxicity, and Earthworm Biodynamics

Vermicompost is an organic fertilizer rich in nutrients, beneficial microbes, and plant growth hormones that not only enhances the growth of crops but also contributes to the improvement in the physicochemical and biological properties of the soil. However, its lower nutrient content makes it less preferable among farmers and limits its applicability. Here, we investigate, for the first time, nutrient enrichment of vermicompost by supplementing the free-floating macrophyte biomass with cow manure and organic nutrient supplements (eggshell, bone meal, banana peel, and tea waste). Free-floating macrophytes are aquatic plants that are found suspended on the water surface, playing a significant role in the structural and functional aspects of aquatic ecosystems. However, uncontrolled proliferation of these macrophytes endangers these ecosystems, having both economic and ecological implications; therefore, they need to be managed. Results showed an enhanced total nitrogen (2.87%), total phosphorus (0.86%), total potassium (3.74%), and other nutrients in vermicompost amended with cow manure and nutrient supplements. Highest biomass gain (710–782 mg), growth rate (11.83–13.04 mg), and reproduction rate (3.34–3.75 cocoons per worm) was also observed, indicating that amending bulking agent and nutrient supplements not only enhance the nutrient content of the final product but also improve overall earthworm activity. The stability and maturity of vermicompost, as indicated by C/N (<20) and Germination Index (>80), indicates that vermicompost obtained is suitable for agricultural applications. The study concluded that amendment of cow manure and organic nutrient supplements results in producing mature and nutrient-enriched vermicompost suitable for sustainable agricultural production

Production of Nutrient-Enriched Vermicompost from Aquatic Macrophytes Supplemented with Kitchen Waste: Assessment of Nutrient Changes, Phytotoxicity, and Earthworm Biodynamics

Vermicompost is an organic fertilizer rich in nutrients, beneficial microbes, and plant growth hormones that not only enhances the growth of crops but also contributes to the improvement in the physicochemical and biological properties of the soil. However, its lower nutrient content makes it less preferable among farmers and limits its applicability. Here, we investigate, for the first time, nutrient enrichment of vermicompost by supplementing the free-floating macrophyte biomass with cow manure and organic nutrient supplements (eggshell, bone meal, banana peel, and tea waste). Free-floating macrophytes are aquatic plants that are found suspended on the water surface, playing a significant role in the structural and functional aspects of aquatic ecosystems. However, uncontrolled proliferation of these macrophytes endangers these ecosystems, having both economic and ecological implications; therefore, they need to be managed. Results showed an enhanced total nitrogen (2.87%), total phosphorus (0.86%), total potassium (3.74%), and other nutrients in vermicompost amended with cow manure and nutrient supplements. Highest biomass gain (710–782 mg), growth rate (11.83–13.04 mg), and reproduction rate (3.34–3.75 cocoons per worm) was also observed, indicating that amending bulking agent and nutrient supplements not only enhance the nutrient content of the final product but also improve overall earthworm activity. The stability and maturity of vermicompost, as indicated by C/N (80), indicates that vermicompost obtained is suitable for agricultural applications. The study concluded that amendment of cow manure and organic nutrient supplements results in producing mature and nutrient-enriched vermicompost suitable for sustainable agricultural production

Supercapacitors production from waste: A new window for sustainable energy and waste management

© 2022 Elsevier LtdThis article deals with the general concepts of new developments in production of high-value activated porous carbon from various types of wastes for use in supercapacitors. Recently, there has been a rise in the manufacture of activated carbon using waste materials since trash is affordable, economical, and easy, and it is also seen as an effective way to combat the waste management issue in the environment. The composition of diverse wastes, including palm, plastic, E-waste, tea, agricultural, and animal wastes, has made waste materials viable candidates for the starting substance of activated carbon for supercapacitor performance. The advantages of several types of waste materials utilized as energy storage are discussed in this work. The procedures for preparing activated carbon, such as pretreatment and activation are addressed. Finally, the economic element of supercapacitor generation from trash is highlighted, as well as future potential for supercapacitor application. This work proposes environment friendly use of waste materials by using activated carbon for energy storage via supercapacitors

Assessment of the Heavy Metal Contamination of Roadside Soils Alongside Buddha Nullah, Ludhiana, (Punjab) India

The present study was carried out to determine the physico-chemical characteristics and heavy metal contents in roadside soil samples collected during 2 sampling periods (September 2018 and April 2019) from 8 different roadside sites lying parallel to the Buddha Nullah, an old rivulet, flowing through Ludhiana, (Punjab) India. The contents (mg/kg) of seven metals (cadmium, chromium, cobalt, copper, lead, nickel and zinc) were estimated using a flame atomic absorption spectrophotometer. Among the metals analyzed, the contents of Cd, Co, Cu, Pb and Zn were found above the permissible limits. The results of the index of geoaccumulation (Igeo), contamination factor (CF), contamination degree (Cdeg), modified contamination degree (mCdeg), the Nemerow pollution index (PI) and pollution load index (PLI) indicate a moderate to high heavy metal contamination of the analyzed soil samples. The results of the potential ecological risk factor (ERi) and potential ecological risk index (RI) indicate a low to moderate risk of heavy metals in the studied soil samples. The Pearson correlation analysis revealed that most of the variables exhibited a statistically significant correlation with one or more variables during the two samplings. Multivariate analysis demonstrates that contents of heavy metals in the study area are influenced by anthropogenic and geogenic factors

Effect of Organic Manures on Growth, Yield, Leaf Nutrient Uptake and Soil Properties of Kiwifruit (<i>Actinidia deliciosa</i> Chev.) cv. Allison

In recent decades, organic kiwifruit farming has come up as a feasible method for high-quality kiwi production without using chemical fertilizers. The primary objective of this research was to investigate how the sole application of organic and the combined application of organic manures affected the growth, yields, and quality of Allison kiwifruit, as well as the soil’s physicochemical characteristics. The field trial was conducted on cv. Allison to determine the efficacy of organic manures (OM) on growth, nutrient absorption, production and soil health. The experiment involved eight treatments, viz.: T1: 100% Dairy manure (DM); T2: 100% Vermicompost (VC); T3: 100% chicken manure (CM); T4: 50% DM + 50% CM; T5: 50% DM + 50% VC; T6: 50% CM + 50% VC; T7: DM + CM + VC in equal proportions; and T8: Recommended nutrients inorganic NPK + 40 kg DM. A randomized complete block design comprising three replicas was used in this investigation. The use of inorganic fertilizers (NPK) in combination with DM enhanced Spad Values Chlorophyll, fruit production, leaf number, leaf area, and stem diameter while also improving the soil’s chemical characteristics. The flower initiation was recorded with DM and Vermicompost (50:50). Furthermore, when compared to inorganic fertilizer treatment, OM treatment significantly improved fruit quality by improving fruit chemical composition in terms of soluble solids contents and leaf nutrient status, as well as improving soil’s physical properties with DM and Vermicompost (50:50). The study’s outcome revealed that OM had a significant impact on flowering time, fruit SSC, leaf nutritional status, and soil physical characteristics. In comparison to organic treatments, recommended fertilizer dosages (NPK + DM) improved plant growth, fruit yield, and soil chemical characteristics

Impact of Aboveground Vegetation on Abundance, Diversity, and Biomass of Earthworms in Selected Land Use Systems as a Model of Synchrony between Aboveground and Belowground Habitats in Mid-Himalaya, India

The population status and biomass of earthworms were studied in three different land use systems of pasture (Pa), silvopasture (SP), and mixed evergreen forest (MEF) from 2019&ndash;2020 in the Solan district of Himachal Pradesh, India. The aim of this study was to assess the population status of earthworms and investigate how different land use systems influence their abundance, diversity, and biomass. Earthworms and soil were sampled using the Tropical Soil Biology and Fertility (TSBF) method in all seasons (winter, spring, summer, monsoon, and autumn). The physicochemical properties of the soil were analyzed to evaluate their effects on the diversity, biomass, and density of animals. The diversity status parameters, such as the Shannon diversity index (H&prime;), Margalef richness index (R), evenness (J&prime;), and dominance index (D), were computed. A total of seven earthworm species, belonging to four families, namely, Amynthas&nbsp;corticis, Aporrectodea rosea, Drawida japonica, Eisenia fetida, Metaphire birmanica, Metaphire houlleti, and Lennogaster pusillus, were identified from all three land use systems. The lowest Shannon diversity index (H&prime;), Margalef index (R), and evenness (J&prime;) index values were registered in MEF (H&prime; = 0.661, R = 0.762, J&prime; = 0.369) compared to those in Pa (H&prime; = 1.25, R = 1.165, J&prime; = 0.696) and SP (H&prime; = 0.99, R = 0.883, J&prime; = 0.552), implying that MEF is the least diversified land system. In contrast, the highest dominance index (D) value was registered in MEF (Pa = 0.39, SP = 0.53, MEF = 0.67), which again showed that MEF is the least diversified land system. The highest values of abundance and biomass were recorded in MEF (754.15 individuals m&minus;2 and 156.02 g m&minus;2), followed by SP (306.13 individuals m&minus;2 and 124.84 g m&minus;2) and Pa (77.87 individuals m&minus;2 and 31.82 g m&minus;2). Both the density and biomass of earthworms increased from Pa to MEF (Pa &lt; SP &lt; MEF). This study is novel because it revealed that the diversity and productivity (biomass and abundance) values of earthworms were negatively correlated (as diversity increased, productivity decreased; as diversity decreased, productivity increased). The total values of abundance and biomass of earthworms in the three land use systems indicated perfect synchrony between aboveground and belowground habitats, whereas the diversity values revealed that MEF was dominated by one or two species and the least diversified. Therefore, for sustainable belowground productivity, aboveground conservation is recommended, and vice versa, regardless of diversity