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Agricultural water productivity is crucial for sustainability amidst the escalating demand for food. Cereals are pivotal in providing nutritious food at affordable prices. This study was based on Ghanaian data spanning from 1992 to 2021 to evaluate water usage in the cultivation of major cereals. It also examined the virtual water losses or gains in cereal trade alongside influencing factors. The analysis utilized secondary data encompassing the virtual water content, production quantity, export and import quantities, distance, GDP per capita, population, and land per capita of Ghana and its 75 trade partners. In the last 5 years, crop water use (CWU) reached an average of 7.08 billion m3/yr for maize, 3.48 billion m3/yr for rice, 1.08 billion m3/yr for sorghum, and 0.63 billion m3/yr for millet production. Ghana’s major partners for exported virtual water (EVW) were Niger, Burkina Faso, South Africa, and Togo. Major partners for imported virtual water (IVW) were Argentina, South Africa, Ukraine, Togo, Russia, Burkina Faso, Canada, Senegal, Nigeria, Portugal, UK, Niger, and the USA. The Panel Least Squares Method of regression was used to apply the Gravity Model principle in assessing influencing factors. The findings indicate that Ghana is a net importer of virtual water in the cereal trade, with significant influences from geographical distance, GDP per capita, population, land per capita, and cereal water use.

This study analyzed the changes and trends in twelve extreme precipitation-based climate indices obtained using daily data from 10 synoptic stations in the Chungcheong region of South Korea during the 1973–2020 period. The climate indices were used to assess the trends in the extreme precipitation characteristics of duration, frequency, and intensity using the innovative trend analysis (ITA) method. The results of the ITA were further compared with two other non-parametric test methods such as Mann–Kendall (MK) and Spearman’s rho (SR). The results showed that most stations exhibited significant increasing trends in all the investigated climate indices at a 95% confidence level as indicated by the ITA method, with only a few stations indicating significant decreasing trends in R95p, R99p, Rx3day, and Rx5day. The sub-trend analysis further revealed the dominance of neutral behavior around the low-value cluster, especially for the extreme precipitation duration. At the same time, increasing trends dominate the high-value cluster at most stations. Meanwhile, only R10mm, R99p, and R95p exhibited monotonic trends in the Boeun and Seosan stations, respectively. Further, the ITA exhibited superior performance over the MK and SR methods by indicating the presence of more significant trends in the climate indices at most stations. The distribution of the extreme precipitation indices for duration, frequency, and intensity indicate the pronounced risk of flood conditions around the north–central and some parts of southern regions, while the western region indicates a potential drought risk, which could greatly impact the water resources and consequently agricultural activities in the study area. The results of this study provide essential information for addressing the climate-related problems of water resource management and agriculture in the study area and other related climatic regions.

Extreme climate change events are major causes of devastating impacts on socioeconomic well-being and ecosystem damage. Therefore, understanding the performance of appropriate climate models representing local climate characteristics is critical for future projections. Thus, this study analyses the performance of 24 GCMs from the Coupled Model Intercomparison Project Phases 5 and 6 (CMIP5 and 6) and their multi-model ensembles in simulating climate variables including average rainfall, maximum (Tmax), and minimum (Tmin) temperatures at annual and seasonal scales over the Chungcheong region of South Korea from 1975 to 2015. A trend analysis was conducted to estimate the future trends in climate variables in the 2060s (2021–2060) and 2080s (2061–2100). Inverse distance weighting and quantile delta mapping were applied to bias-correct the GCM data. Further, six major evaluating indices comprising temporal and spatial performance assessments were used, after which a comprehensive GCM ranking was applied. The results showed that CMIP6 models performed better in simulating rainfall, Tmax, and Tmin at both temporal and spatial scales. For CMIP5, the top three performing models were GISS, ACCESS1-3, and MRI-CGCM3 for rain; CanESM2, GISS, and MPI-ESM-L-R for Tmax; and GFDL, MRI-CGCM3, and CanESM2 for Tmin. However, the top three performing models in the CMIP6 were MRI-ESM2-0, BCC_CSM, and GFDL for rain; MIROC6, BCC_CSM, and MRI-ESM2-0 for Tmax, and GFDL, MPI_ESM_HR, and MRI-ESM2-0 for Tmin. The multi-model ensembles (an average of the top three GCMs) performed better in simulating rain and Tmin for both CMIP5 and CMIP6 compared with multi-model ensembles (an average of all the GCMs), which only performed slightly better in simulating Tmax. The trend analysis of future projection indicates an increase in rain, Tmax, and Tmin; however, with distinct changes under similar radiative forcing levels in both CMIP5 and CMIP6 models. The projections under RCP4.5 and RCP8.5 increase more than the SSP2-4.5 and SSP5-8.5 scenarios for most climate conditions but are more pronounced, especially for rain, under RCP8.5 than SSP5-8.5 in the far future (2080s). This study provides insightful findings on selecting appropriate GCMs to generate reliable climate projections for local climate conditions in the Chungcheong region of South Korea.

With the increasing demand for electronic devices that use batteries, e-waste is also becoming a major threat to the environment. Battery e-waste contains hazardous heavy metals that affect the health of the soil ecosystem. Thus, the present study evaluates the cadmium (Cd) and lead (Pb) phytoextraction potential of coco grass (Cyperus rotundus L.) grown in soils contaminated with battery scrap waste (BSW). Pot experiments were conducted to grow C. rotundus under different treatments (0%: control, T1: 1%, T2: 2%, T3: 3%, and T4: 4%) of BSW mixed with soil (w/w). The results showed that BSW mixing significantly (p < 0.05) increased the physicochemical properties and heavy metal (Cd and Pb) content in the soil. BSW mixing resulted in a reduction in growth and biochemical traits of C. rotundus and an increase in oxidative stress enzymes with an increase in BSW dose. The Pearson correlation studies also showed that soil HM concentration had a negative influence on the growth and biochemical parameters of C. rotundus. The bioaccumulation and translocation factor analysis showed that C. rotundus was a hyperaccumulator plant with a maximum accumulation of Cd and Pb (38.81 and 109.06 mg·kg−1) in root parts followed by the whole plant (277.43 and 76.10 mg·kg−1) and shoot (21.30 and 22.65 mg·kg−1) parts. Moreover, predictive models based on multiple linear regression (MLR) and artificial neural network (ANN) approaches were developed for Cd and Pb uptake by C. rotundus. Mathematical modeling results showed that soil properties were useful to construct quality MLR and ANN models with good determination coefficient (R2 > 0.98), model efficiency (ME > 0.99), and low root mean square error (RMSE < 5.72). However, the fitness results of the ANN models performed better compared with those of the MLR models. Overall, this study presents an efficient and sustainable strategy to eradicate hazardous HMs by growing C. rotundus on BSW-contaminated soils and reducing its environmental and health consequences.

The novel coronavirus, SARS-CoV-2, which has caused millions of death globally is recognized to be unstable and recalcitrant in the environment, especially in the way it has been evolving to form new and highly transmissible variants. Of particular concerns are human-environment interactions and the handling and reusing the environmental materials, such as effluents, sludge, or biosolids laden with the SARS-CoV-2 without adequate treatments, thereby suggesting potential transmission and health risks. This study assesses the prevalence of SARS-CoV-2 RNA in effluents, sludge, and biosolids. Further, we evaluate the environmental, ecological, and health risks of reusing these environmental materials by wastewater/sludge workers and farmers. A systematic review of literature from the Scopus database resulted in a total of 21 articles (11 for effluents, 8 for sludge, and 2 for biosolids) that met the criteria for meta-analysis, which are then subdivided into 30 meta-analyzed studies. The prevalence of SAR-CoV-2 RNA in effluent and sludge based on random-effect models are 27.51 and 1012.25, respectively, with a 95% CI between 6.14 and 48.89 for the effluent, and 104.78 and 1019.71 for the sludge. However, the prevalence of SARS-CoV-2 RNA in the biosolids based on the fixed-effect model is 30.59, with a 95% CI between 10.10 and 51.08. The prevalence of SARS-CoV-2 RNA in environmental materials indicates the inefficiency in some of the treatment systems currently deployed to inactivate and remove the novel virus, which could be a potential health risk concern to vulnerable wastewater workers in particular, and the environmental and ecological issues for the population at large. This timely review portends the associated risks in handling and reusing environmental materials without proper and adequate treatments.

In this study, the potential use of sewage sludge (SS) as a fertilizer source for cultivated Dhaincha (Sesbania bispinosa (Jacq.) W.Wight) crops was investigated. Field experiments were conducted using different doses of SS such as 0% (T0), 5% (T1), 10% (T2), and 15% (T3) to amend the soil (w/w). The findings showed that soil amended with SS significantly (p < 0.05) improved the response parameters of S. bispinosa with an increase in the dose of SS from 0% to 15%. In particular, the T3 treatment gave the best results (mean values) for plant growth and yield parameters such as plant height (380.59 cm), fresh weight (1.47 kg/plant), dry weight (0.27 kg/plant), base diameter (3.19 cm), seed yield (44.71 g/plant), total chlorophyll (3.15 mg/g fwt), carotenoids (0.88 mg/g fwt), carbohydrates (9.40 mg/g), and phenol (0.13 mg/g) contents. Moreover, the selected proximate and fiber characteristics of the S. bispinosa crop were significantly (p < 0.05) improved by the same treatment (T3); such as ash (7.25%), crude fiber (32.70%), crude protein (15.94%), lignin (24.60%), cellulose (37.25%), fiber weight (3.06 g/plant), stick weight (32.08 g/plant), fiber: stick ratio (0.10), fiber diameter (26.97 µm), ultimate tensile strength (855.98 MPa), strength (58.92 g/tex), density (1.54 g/cm3), and luster (45.65%) compared with the control treatment (T0). The bioaccumulation factor (BAF) studies showed that the S. bispinosa plant was capable of accumulating selected heavy metals from the soil following the order: Fe > Mn > Zn > Cu > Cd > Cr. The study suggested a sustainable approach for efficient soil fertilization and high-quality S. bispinosa fiber production that could minimize the environmental pollution caused by the unsafe disposal of SS.

The present study aimed to investigate the impact of sewage sludge (SS) amendment on the growth, yield, and biochemical attributes of the marigold (Tagetes erecta L. var. Pusa Basanti Gainda) crop. For this purpose, marigold flowers were cultivated using three different treatments of SS, i.e., 0% (control with no SS), 5%, and 10%. Multiple linear regression (MLR) modeling was performed to develop prediction models for the impact of soil properties on heavy metals uptake by marigold plants. The results showed that the growth, yield, and biochemical attributes of marigold plants significantly (p < 0.05) increased with an increase in SS dose from 0 to 10%. The most feasible SS treatment was found to be 10%, which achieved a maximum flower yield of 318.42 g/plant. On the other hand, the bioaccumulation factor (BAF) values (>1) showed that the marigold plant was capable of uptaking significant contents of six heavy metals in the order of Cd < Cr < Cu < Zn < Mn < Fe. The MLR-based predictive models were capable of precisely predicting the contents of most heavy metal uptake by marigold plants as indicated by the coefficient of determination (R2 > 0.73), model efficiency (ME > 0.49), root mean square error (RMSE < 3.25), and analysis of variance (ANOVA; p < 0.05) results. Overall, this study presented a novel approach to floriculture by sustainable management of SS while reducing public health and environmental impacts.

The potential use of carbon dioxide (CO2) and wastewater released from a mushroom farm for the cultivation of Chlorella vulgaris microalga was investigated in this study. For this purpose, a microcontroller-based aided CO2 capture and mixing prototype was constructed for the cultivation of C. vulgaris under varying concentrations of mushroom farm wastewater (0 as control, 50 and 100%). The results showed that the constructed prototype was helpful to maintain desirable CO2 levels (6000 ppm) in the mushroom cultivation chamber with constant CO2 supply to algal culture, i.e., 0.6% at an airflow rate of 50 mL/min. After 16 days of algal cultivation, it was observed that the maximum significant (p < 0.05) algal biomass production of 2.550 ± 0.073 mg/L was recorded in 50% wastewater concentration followed by 100% and control. Also, the maximum removal of selected mushroom farm wastewater pollutants, such as total dissolved solids (84.00 ± 1.37%), biochemical oxygen demand (90.17 ± 2.42%), chemical oxygen demand (91.53 ± 0.97%), total nitrogen (86.27 ± 1.60%) and total phosphorus (94.19 ± 2.33%), was achieved in 50% concentration of wastewater treatment with maximum first-order rate constant (k) values. In addition, the algal growth kinetics results showed that the logistic model fit best compared to the modified Gompertz model, based on selected validation tools, such as experimental vs. predicted values, coefficient of determination (R2 > 0.9938), model efficiency (ME > 0.98) and root mean square error (RMSE < 0.03). The post-harvest characterization of algal biomass revealed that the proximate, biochemical, ultimate elements (carbon, oxygen and nitrogen) and structural properties were significantly higher in 50% treatment than those in 100% and control treatments. Therefore, the findings of this study are novel and provide significant insight into the synergistic use of CO2 and wastewater produced by mushroom farms for algal cultivation and biological wastewater treatment.

This study investigated the monitoring of six heavy metals (Cd, Cr, Cu, Fe, Mn, and Zn) in pond water, sludge, and cultivated water chestnut (Trapa natans L.) crops in Saharanpur district of Uttar Pradesh, India. For this purpose, samples of pond water, sludge, and T. natans plant (nut, shoot, and root) were collected in November of 2021 and 2022 from three zones (Zone 1: agricultural area irrigated with borewell water, Zone 2: urban area irrigated with municipal wastewater, and Zone 3: rural area irrigated with mixed type of wastewater) and subsequently analyzed for heavy metal concentration using atomic absorption spectroscopy. The results showed that the physicochemical and heavy metal characteristics of pond water and sludge were significantly (p < 0.05) higher in Zone 2 and 3 than to those in Zone 1. The concentration of heavy metals in T. natans root was comparatively high followed by shoot and nut parts. The bioaccumulation factor (BAF) was maximum while using pond water as a reference medium compared to pond sludge. Overall, the increasing order of heavy metals in T. natans was observed as Cd < Cr < Cu < Zn < Mn < Fe. In the edible part (nut) of T. natans, the average contents of Cd (0.005 ± 0.002 mg/kg), Cr (0.134 ± 0.009 mg/kg), Cu (1.043 ± 0.104 mg/kg), Fe (9.589 ± 0.957 mg/kg), Mn (4.326 ± 0.753 mg/kg), and Zn (1.540 ± 0.537 mg/kg) were comparatively less than shoot and root parts. Overall, the results revealed that T. natans irrigated with contaminated irrigation supplies at Zone 2 and 3 showed the highest BAF of heavy metals than Zone 1. Because the heavy metal concentrations in edible parts of T. natans did not exceed the threshold limits, the contaminated water sources in the Saharanpur region of India should be used in a safe and controlled manner.

The abundant biomass growth of aquatic macrophytes in wetlands is one of the major concerns affecting their residing biota. Moreover, the biomass degenerates within the wetlands, thereby causing a remixing of nutrients and emission of greenhouse gases. Therefore, it is crucial to find sustainable methods to utilize the biomass of aquatic macrophytes devoid of environmental concerns. The present study investigates the utilization of the biomass of three aquatic macrophytes, including the lake sedge (CL: Carex lacustris Willd.), water hyacinth (EC: Eichhornia crassipes Mart. Solms), and sacred lotus (NL: Nelumbo nucifera Gaertn.) to produce oyster (Pleurotus ostreatus var. florida) mushrooms. For this purpose, different combinations of wheat straw (WS: as control) and macrophyte’s biomass (WH) such as control (100% WH), CL50 (50% WH + 50% CL), CL100 (100% CL), EC50 (50% WH + 50% EC), EC100 (100% EC), NL50 (50% WH + 50% NL), and NL100 (100% NL) were used for P. florida cultivation under controlled laboratory conditions. The results showed that all selected combinations of wheat straw and macrophyte biomass supported the spawning and growth of P. florida. In particular, the maximum significant (p < 0.05) growth, yield, bioefficiency, proximate, and biochemical parameters were reported using the WH substrate followed by CL, NL, and EC biomass, which corresponds to the reduction efficiency of the substrate parameters. Therefore, the findings of this study reveal that the biomass of selected aquatic macrophytes can be effectively utilized for sustainable mushroom cultivation while minimizing the risk associated with their self-degeneration.

The world’s sustainable growth is being severely hampered by the inefficient use of water resources. Despite the widely acknowledged importance of trade in global and regional water and food security, societal reliance on local production, as well as international trade, remains inadequately assessed. Therefore, using South Korea as a case study, this study fills in this research gap by applying the virtual water concept, the logarithmic mean divisia index (LMDI) method, and the Tapio decoupling model. The virtual water concept was used to estimate South Korea’s net virtual water trade for major grain crops from 1992 to 2017. Then, the LMDI method was utilized to assess the driving factors causing changes in net virtual water trade. Lastly, the Tapio decoupling model was used to investigate the decoupling relationships between economic growth and the driving factors of net virtual water trade. The results showed that South Korea remains a net importer of virtual water flows with respect to grain crops, with an average import of 16,559.24 million m3 over the study period. In addition, the change in net virtual water trade could be attributed to the water intensity effect, product structure effect, economic effect, and population effect. However, water intensity and economic effects were the major decisive factors for decreases and increases in net virtual water trade, respectively, while the population and product structure effects had minor positive influences on the net virtual water trade. Furthermore, water intensity and economic growth showed a strong decoupling in most periods, while the decoupling state between product structure and economic growth was observed as expansive negative decoupling. Likewise, population size and economic growth showed a weak decoupling in most periods. The results reveal South Korea’s status as it concerns the virtual water trade of grain crops, thus providing valuable insights into the sustainability of trade activities for the management of local water resources.

Heavy metal pollution from industrial wastewaters has become an issue of global concern. These wastewaters are frequently used for inland irrigation which possess a serious risk of heavy metal contamination of both soil and cultivated crops. The problem is more common in developing countries like India where industrial wastewaters are often discharged without appropriate treatments. Therefore, this study aimed at assessing the impact of paper mill effluent for irrigation on the growth, productivity, and heavy metal accumulation potential of two rice (Oryza sativa L.) varieties (PB-1121 and PR-121). Water, soil, and rice crop samples were obtained from the vicinity of Saharanpur city, Uttar Pradesh, India, and subsequently analyzed for selected physicochemical and heavy metal parameters. Results showed that paper mill effluent and nearby Kali River water had significant (p < 0.05) loads of pollutants that impacted the soil properties. Moreover, the maximum plant height (123.48 ± 4.86 and 98.83 ± 2.02 cm); total chlorophyll (6.70 ± 0.25 and 6.64 ± 0.17 mg/g); leaf carotenoids (0.67 ± 0.08 and 0.63 ± 0.05 mg/g); starch content (71.08 ± 2.05 and 72.60 ± 1.63%); amylose content (25.10 ± 1.32 and 20.28 ± 1.24%); crop yield (4270.20 ± 75.12 and 5830.58 ± 63.10 kg/ha); and straw yield (5472.05 ± 93.90 and 6683.76 ± 61.26 kg/ha) of PB-1121 and PR-121, respectively, were observed using Kali River water irrigation source as compared to paper mill effluent and borewell water. The order of heavy metal accumulation in rice straw and grain followed: Fe > Mn > Zn > Cu > Cr > Cd. Similarly, the bioaccumulation factors for heavy metals in rice straw and grain were observed as >1 and 1). As a result, the findings of this study provide useful information about the current state of heavy metal pollution and the health risks associated with rice crops irrigated with contaminated water sources.

This study aimed at assessing the concentration of six heavy metals (Cd, Cr, Cu, Fe, Mn, and Zn) in two wild edible oyster mushrooms (Pleurotus ostreatus and Pleurotus djamor) collected from Rajaji National Park in Haridwar, India. For this purpose, mushroom samples were collected from selected locations (forest, residential, tourist, industrial areas, and transportation activities) from June 2021 to July 2022 and subsequently analyzed for selected heavy metals using atomic absorption spectroscopy (AAS). Results showed that both Pleurotus spp. had significantly varying (p < 0.05) concentrations of heavy metals. However, P. ostreatus showed relatively higher concentration levels of these metals compared to P. djamor. The mean concentrations (mg/kg dry weight) of the Cd, Cr, Cu, Fe, Mn, and Zn in P. ostreatus and P. djamor were 0.10 and 0.08, 0.87 and 0.64, 16.19 and 14.77, 28.49 and 27.15, 9.93 and 8.73, and 18.15 and 15.76, respectively. As indicated by the multivariate analysis tools i.e., principal component analysis (PCA) and hierarchical cluster analysis (HCA), the locations near the residential, industrial, and transportation activities had higher concentration levels of heavy metals. Moreover, the health risk studies using the target hazard quotient (THQ < 1) showed no significant health risk as the consumption of both Pleurotus spp., except for at one location, had high-traffic activities. The findings of this study provide vital information about the occurrence of potentially toxic heavy metals in wild edible Pleurotus spp. in Rajaji National Park in Haridwar, India representing a safeguard for mushroom consumers.

This paper investigated the impact of the combined use of spent mushroom substrate (SMS) biochar and plant-growth-promoting rhizobia (PGPR) on the growth, yield, and biochemical response of cauliflower (Brassica oleracea var. botrytis). A preliminary study was conducted under greenhouse condition using six treatments (sextuplicate) as control (no addition), T1 (PGPR), T2 (5 g/Kg biochar), T3 (5 g/Kg biochar + PGPR), T4 (10 g/Kg biochar), and T5 (10 g/Kg biochar + PGPR) under greenhouse conditions. The Scanning Electron Microscopy (SEM-Zeiss), Energy Dispersive Spectroscopy (EDS), and Fourier’s transform infrared spectroscopy (FTIR) analyses showed that biochar produced from slow pyrolysis of SMS had advantageous structural, functional, and morphological properties for agricultural use. Results showed that SMS biochar addition aids the acceleration of soil nutrient properties. SMS biochar and PGPR application also significantly (p < 0.05) improved the selected growth, yield, and biochemical parameters of cauliflower. In particular, the highest cauliflower yield (550.11 ± 10.05 g), fresh plant biomass (1.66 ± 0.04 Kg), dry plant biomass (149.40 ± 4.18 g), plant height (22.09 ± 0.14 cm), root length (11.20 ± 0.05 cm), plant spread (28.35 ± 0.18 cm), and the number of leaves (12.50 ± 0.50) were observed in T5 treatment. Similarly, the best values for biochemical parameters and enzyme activities such as total chlorophyll (TC: 3.13 ± 0.07 mg/g), superoxide dismutase (SOD: 79.12 ± 1.29 µg/g), catalase (CAT: 55.70 ± 2.52 µg/g), peroxidase (POD 30.18 ± 0.37 µg/g), total phenolics (TP: 19.50 ± 0.31 mg/g), ascorbic acid (AA: 14.18 ± 0.55 mg/g), and total carotenoids (TCT: 150.17 ± 8.20 µg/100 g) were also recorded in the T5 treatment. The application of SMS biochar and PGPR showed a positive correlation with growth, yield, and biochemical response of cauliflower, as indicated by the Pearson correlation analysis. The findings of this study suggest efficient recycling of mushroom industry waste for biochar production and the use of PGPR to improve nutrient utilization in sustainable agriculture.

The spatial assessment of four heavy metals (Cd, Cr, Pb, and As) in two mango fruit (Mangifera indica L.) varieties (Dasheri and Langra) collected from the Saharanpur district, Uttar Pradesh, India, was investigated in this study. The samples of ripe mango fruits were collected from the orchards of 12 major towns in the Saharanpur district from May to June 2022. Heavy metal analysis using atomic absorption spectroscopy (AAS) showed the presence of all selected heavy metals. Specifically, the concentration (mg/kg dry weight basis) range of Cd (0.01–0.08), Cr (0.11–0.82), Pb (0.02–0.15), and As (0.01–0.14) did not exceed the safe limits. The geospatial variation in the heavy metal concentration was significantly (p < 0.05) different as indicated by the inverse distance weighting (IDW) interpolation and analysis of variance (ANOVA) results. The multivariate statistical analysis using principal component (PC) and agglomerative hierarchical cluster (AHC) analyses revealed that the Saharanpur city location had the highest levels of selected heavy metals out of the 12 sampling locations. In this, the Dasheri variety was identified to have higher heavy metal concentrations in comparison to the Langra variety. Moreover, the health risk study using the target hazard quotient (THQ) confirmed that the levels did not exceed the safe health risk index (HRI) limit of 1. However, the health risk assessment for the child group showed relatively high HRI values (

Nowadays, the increase in the wastewater generated from the mushroom cultivation sector has become a serious environmental pollution concern. Therefore, the present study aimed to assess the efficiency of two water ferns (Azolla pinnata and A. filiculoides) in phytoremediation of mushroom farm wastewater (MFW) under stagnant and flowing tank reactor systems. For this, the laboratory scale experiments were conducted using five treatments, i.e., control (absolute borewell water), S50 (15 L borewell water + 15 L MFW: stagnant mode), S100 (30 L MFW: stagnant mode), F50 (15 L borewell water + 15 L MFW: flowing mode), F100 (30 L MFW: flowing mode), separately for both Azolla spp. After 15 days, A. pinnata and A. filiculoides significantly (p < 0.05) reduced the physicochemical parameters of MFW such as pH (18.87 and 18.56%), electrical conductivity (EC: 80.28 and 78.83%), total dissolved solids (TDS: 87.12 and 86.63%), biochemical oxygen demand (BOD: 90.63 and 89.90%), chemical oxygen demand (COD: 86.14 and 85.54%), and total Kjeldahl’s nitrogen (TKN: 84.22 and 82.44%), respectively, in F100 treatment. Similarly, the highest growth and biochemical parameters of Azolla spp. were also observed while using absolute MFW treatment in a flowing tank reactor system. Moreover, out of the two tested growth kinetic models, the logistic model showed better fitness to the experimental data and prediction of critical growth parameters compared to the modified Gompertz model. The findings of this study are novel and suggest sustainable upcycling of MFW using plant-based treatment techniques with the production of high-quality Azolla spp. biomass.

Agro-wastes, such as crop residues, leaf litter, and sawdust, are major contributors to global greenhouse gas emissions, and consequently a major concern for climate change. Nowadays, mushroom cultivation has appeared as an emerging agribusiness that helps in the sustainable management of agro-wastes. However, partial utilization of agro-wastes by mushrooms results in the generation of a significant quantity of spent mushroom substrates (SMS) that have continued to become an environmental problem. In particular, Shiitake (Lentinula edodes Berk.) mushrooms can be grown on different types of agro-wastes and also generate a considerable amount of SMS. Therefore, this study investigates the biotransformation of SMS obtained after Shiitake mushroom cultivation into biogas and attendant utilization of slurry digestate (SD) in tomato (Solanum lycopersicum L.) crop fertilization. Biogas production experiments were conducted anaerobically using four treatments of SMS, i.e., 0% (control), 25, 50, and 75% inoculated with a proportional amount of cow dung (CD) as inoculum. The results on biogas production revealed that SMS 50% treatment yielded the highest biogas volume (8834 mL or 11.93 mL/g of organic carbon) and methane contents (61%) along with maximum reduction of physicochemical and proximate parameters of slurry. Furthermore, the biogas digestate from 50% treatment further helped to increase the seed germination (93.25%), seedling length (9.2 cm), seedling root length (4.19 cm), plant height (53.10 cm), chlorophyll content (3.38 mg/g), total yield (1.86 kg/plant), flavonoids (5.06 mg/g), phenolics (2.78 mg/g), and tannin (3.40 mg/g) contents of tomato significantly (p < 0.05) in the 10% loading rate. The findings of this study suggest sustainable upcycling of SMS inspired by a circular economy approach through synergistic production of bioenergy and secondary fruit crops, which could potentially contribute to minimize the carbon footprints of the mushroom production sector.

This study presents a spatial assessment of eight potentially toxic elements (PTE: Cd, Cr, Cu, Fe, Pb, Ni, Mn, and Zn) in white button (Agaricus bisporus J.E. Lange) mushroom samples collected from the local vegetable markets of Uttarakhand State, India. Fresh A. bisporus samples were collected from thirteen districts and fifteen sampling locations (M1-M15) and analyzed for the concentration of these PTE using atomic absorption spectroscopy (AAS). The results revealed that A. bisporus contained all eight selected PTE in all sampling locations. Based on the inverse distance weighted (IDW) interpolation, principal component (PC), and hierarchical cluster (HC) analyses, the areas with a plane geographical distribution showed the highest PTE concentrations in the A. bisporus samples as compared to those in hilly areas. Overall, the decreasing order of PTE concentration in A. bisporus was recognized as Fe > Zn > Mn > Cr > Cu > Ni > Cd > Pb. The Kruskal–Wallis ANOVA tests displayed a highly significant (p < 0.05) difference among the sampling locations. However, the concentration of PTE was below permissible limits, indicating no potential hazard in consuming the A. bisporus. Similarly, the health risk assessment studies using the target hazard quotient (THQ) also showed no significant health risk associated with the consumption of A. bisporus being sold in the local mushroom markets of Uttarakhand, India. This study is the first report on state-level monitoring of PTE in A. bisporus mushrooms, which provides crucial information regarding the monitoring and occurrence of potentially toxic metallic elements.

This study investigates the sustainable production of Shiitake (Lentinula edodes) mushroom using agro-industrial wastes. The substrate of Shiitake (80% rice straw + 20% sugar cane bagasse) was moistened with 0 (freshwater as control), 50, and 100% concentrations of secondarily treated dairy plant and sugar mill wastewaters (DPW and SMW). After proper sterilization, the cultivation was carried out under controlled environmental conditions using the bag log method for 100 days. The results revealed that DPW and SMW moistening significantly (p < 0.05) increased the nutrient levels of the formulated substrate which later gave better mushroom yield. The highest Shiitake mycelial coverage (90.70 ± 1.47 and 88.65 ± 1.82%), yield (186.00 ± 3.10 and 176.09 ± 4.12 g/kg fresh substrate), biological efficiency (80.00 ± 0.58 and 75.73 ± 0.93%), total phenol (2.84 ± 0.03 and 2.69 ± 0.03 mg/g), ascorbic acid (0.34 ± 0.03 and 0.32 ± 0.02 mg/g), and β-carotene (2.48 ± 0.06 and 2.29 ± 0.02 μg/g) contents with the minimum time taken for spawn running (60 ± 1 days) was observed using a 50% concentration treatment of both DPW and SMW, respectively. Besides this, the kinetic studies using a first-order-based model showed acceptable accuracy in predicting the rate constant for substrate delignification and heavy metal uptake by Shiitake mushroom. These findings suggest a novel approach for sustainable mushroom cultivation using agro-industrial wastes. The concept can be used for the production of high-quality mushrooms for edible and medicinal purposes while contributing toward the United Nations’ Sustainable Development Goals (SDGs 12) on responsible consumption and production of superfoods.

This research investigated the combined use of sewage sludge (SS) and plant growth-promoting rhizobia (PGPR) for Ridge gourd (Luffa acutangula (L.) Roxb.) cultivated under field conditions. The different treatments of SS and PGPR such as 0% (soil as control), 5% SS, 5% SS + PGPR, 10% SS, and 10% SS + PGPR were applied to assess their impacts on seedling growth, biochemical response, and yield performance of Ridge gourd. The results showed that the highest seedling emergence (92.3 ± 2.1%), fresh biomass (9.6 ± 0.3 g), growth rate (1.4 ± 0.1 g/day), seedling length (15.5 ± 0.3 cm), root length (10.4 ± 0.3 cm), total chlorophyll (3.2 ± 0.1 mg/g), crop yield (13.8 ± 0.1 kg/plant), and average crop yield per harvest (2.8 ± 0.1 kg/plant) were observed in 10% SS + PGPR treatment. The enzyme activities of superoxide dismutase (SOD; µg/g) and catalase (CAT: µg/g) were significantly lowered after PGPR inoculation in higher SS treatments. The results of principal component (PC) and Euclidian clustered distance analyses showed a positive influence of SS dose on soil nutrient availability and Ridge gourd’s growth, biochemical responses, and yield performance. Moreover, the elemental analysis showed that the bioaccumulation factor (BAF < 0.90) and health risk index (HRI < 0.40) of selected metal elements (Cd, Cr, Cu, Fe, Mn, and Zn) were within the permissible limits, indicating consumption of Ridge gourd fruits was safe. The outcomes of this study suggest the potential use of SS and PGPR for improved Ridge gourd production and contribution towards sustainable development goal (SDG) 12 on responsible consumption and production of vegetable crops.

The present study focused on the use of sewage sludge (SS) as a casing material amendment and the potential uptake of metal elements by the cultivated white button (Agaricus bisporus: MS-39) mushroom. Laboratory experiments were performed under controlled environmental conditions to grow A. bisporus on the composted wheat straw substrate for 50 days. Different treatments (0, 50, 100, 150, and 200 g/kg) of casing material were prepared by mixing garden and dried SS and applied on the mushroom substrate after proper sterilization. The results revealed that SS application was significant (p < 0.05) in accelerating mushroom yield with a biological efficiency of 65.02% for the mixing rate of 200 g/kg. Moreover, the maximum bioaccumulation of selected metal elements (Cu, Cr, Cd, Fe, Mn, and Zn) was observed using the same treatment. Additionally, the multiple regression models constructed for the uptake prediction of metal elements showed an acceptable coefficient of determination (R2 > 0.9900), high model efficiency (ME > 0.98), and low root mean square error (RMSE < 0.410) values, respectively. The findings of this study represent sustainable use of SS for the formulation of mushroom casing material contributing toward synergistic agro-economy generation and waste management.

Hydrological models have become an important tool for the efficient management of water resources. However, selection of appropriate models for evapotranspiration (ET) computations in river basins remains challenging to watershed managers, especially in data-scarce regions. The performance of Soil and Water Assessment Tool (SWAT)-based model for the prediction of potential and actual evapotranspiration (PET and AET) of Ogun- Oshun river basin, Nigeria was investigated. Spatial and meteorological data was applied in setting up Mapwindow SWAT model. The three existing methods: Penman-Monteith, Priestly-Taylor (radiation-based) and Hargreaves (temperature-based), available in SWAT-were applied for the evaluation of PET and AET using soil, topographic, land-use and meteorological data as input parameters. The model results show a good correlation between the simulated and observed dataset as shown by Nasch-Sucliffe efficiency and coefficient of determination values. For the 30 year-simulation period, the predicted average PET values for Penman- Monteith, Priestley-Taylor and Hargreaves methods were 1791.516, 1684.597 and 1724.563 mm with corresponding standard deviation values of 89.322, 53.824 and 77.867 mm, respectively. The analysis indicated that Penman-Monteith and Hargreaves methods yielded almost the same results, while Priestly-Taylor method slightly differs, which establishes that it is not very suitable for arid/semi-arid regions. The study could be beneficial to watershed managers in addressing climate-related problems and for sustainable water resource management. [ABSTRACT FROM AUTHOR]