1 Introduction

Agricultural residue burning is a prevalent practice in many regions, particularly in the Indo-Gangetic plains of India, where it significantly impacts air quality, soil health, and human well-being. This review paper synthesizes current knowledge on the environmental and health effects of crop residue burning, highlighting the urgent need for sustainable management practices. The frequent in-situ burning of residues, especially rice and wheat, releases high levels of particulate matter (PM10, PM2.5, PM1) and gaseous pollutants (NOx, SO2, CO2), contributing to severe air pollution and associated health risks, including respiratory and cardiovascular diseases. Additionally, this practice leads to substantial nutrient loss in soils, adversely affecting agricultural productivity.

Other than India, in Mexico, a comprehensive assessment of biomass availability and seasonal variations revealed a substantial amount of biomass residue through spatial data analysis tools. This residue was estimated to be 87.94 million tonnes (Mt) per year. Of this total crop residue, 37.54 Mt dry matter (DM) per year is readily available for biofuel production. The primary crop waste contributes 30.53 Mt DM per year, and secondary crop leftovers account for 7.01 Mt DM per year. Overall, 95.8% of the available crop residue in the country comes from maize, beans, sugarcane, wheat, sorghum, and barley [1]. In Ethiopia, the estimated total accessible bioenergy amounts to 750 petajoules (PJ) per year, comprising forest biomass waste (46.5%), crop leftovers (34%), animal waste (18.8%), and municipal solid waste (0.05%). The country maintains its bioenergy database and focuses on developing technologies to harness untapped energy for sustainable development [2].

Vietnam generates approximately 39 Mt of paddy residue each year. A considerable amount of this residue is used for livestock feed, field mulching, and energy generation, while a significant portion is burned on fields. This practice increases greenhouse gas concentrations in the atmosphere and depletes vital soil nutrients such as nitrogen (N), phosphorus (P), and potassium (K) [3]. In China, residues from major crops like wheat, paddy, and maize were collected from six major agricultural zones and examined for PM2.5, emission factors (EFs), organic carbon (OC), and water-soluble ions. No significant variations were observed in the combustion profiles of the three crop residues. However, potassium (K) and chloride (Clˉ) were identified as influential ions, and PM2.5 was recorded as the predominant pollutant [4].

Globally, crop residue was estimated at 3803 Mt, equivalent to 60,848 million British thermal units (MBTU) and 1534.37 tonnes of oil equivalent (TOE) in 2003. By 2013, these figures had increased to 5011 Mt, 80,176 MBTU, and 2021.75 TOE. Similar energy estimations were made for Asia, the USA, Europe, and Africa. Thailand evaluated the emission levels of air pollutants from open crop residue burning in 2018. Using country data and remote sensing tools, they analyzed PM10 and lesser particles. During the 2010–2017 agricultural years, 61.87 Mt of paddy waste was produced, of which only 23.0% was exposed to open burning. This emitted 5.34 ± 2.33 Mt of carbon dioxide, 44 ± 14 kilotonnes (Kt) of methane, 43 ± 29 Kt of PM2.5, and 2 ± 1 Kt of PM10 [5]. China also monitored particulate matter emissions (PM2.5 and PM10) and studied the correlation and differences in particulate matter levels from crop residue burning. Ground inspections and remote sensing tools (MODIS) data revealed seasonal emission correlations, with the highest emissions recorded in autumn due to intensive crop residue burning during this season [6].

Various agricultural crop residues are used to produce biofuel through different treatments and conversion techniques [7]. In northern China, fuel wood, indoor biomass, or crop residue combustion is a major source of polycyclic aromatic hydrocarbons (PAHs) emissions [8]. In India, agricultural waste and biogas production possibilities, updated technologies, government initiatives, and policy regulations discussed earlier [9]. They highlighted the challenges in biogas production and opportunities for circular economy development from agricultural waste management and climate change scenarios. Efforts were made to promote community resilience in waste management through an innovation program in collaboration with the United States Consulate General in Mumbai (2017). This program aimed to develop solid waste management systems aligned with circular economy principles in rural and urban India [10]. The Indian agriculture sector is a significant contributor to greenhouse gas emissions from farming lands. Traditional agricultural waste management practices in central India exacerbate pollution. The review discusses various technological advancements and strategies for managing crop residues, such as the use of machinery like the Happy Seeder and Super Straw Management System, biogas production, biochar preparation, and bioethanol production. These methods offer promising solutions for mitigating the environmental impacts of residue burning while enhancing soil health and promoting renewable energy sources. The paper also explores policy frameworks, community engagement, and global collaboration as essential components for the successful implementation of sustainable practices (Table 1).

Table 1 World agriculture waste generation during the years 2003 and 2013, estimated energy potential equal to common energy resources [59]
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1.1 Agricultural residue generation; Indian scenarios

India, the seventh-largest nation in the world, spans 329 million hectares (32,87,263 sq. km), with 195 million hectares of cropped land and 140 million hectares of net sown fields. The total cultivable land in the country is 83 million hectares, primarily dependent on rainfall. Approximately 47.7% of Indian agricultural lands rely on beneficial farming practices, and 51% of the irrigated lands in India contribute to 11% of the cultivated lands worldwide [11]. According to the Indian Council for Agricultural Research (ICAR), crop residue yield is considered in tonnes per hectare for various crop types and projected in a tabular format (Table 2). Each state's bioenergy production potential is based on ICAR's published data (Fig. 1). The north-central region of India produces 620 megatons of crop residue annually, with 30% comprising rice and wheat crop waste. Of the total crop residue, around 16% is burned, including 62% of rice and wheat residues [12].

Table 2 Crop residue yield range in India, dry matter, and net calorific values of agricultural leftover [13]
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Fig. 1
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India's bioenergy production potential

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The generation of bio-waste has increased with India's growing population, including crop residue, livestock leftovers, and garbage waste. Currently, managing crop residue is a significant problem due to the lack of farmer-friendly methods. In-situ crop residue burning damages soil health, contributes to global warming, climate change, and toxic metal contamination. In a comprehensive attempt, the total crop waste products across the country were examined. During the 2014–15 agricultural years, 516 different varieties of crop wastes were produced. The largest portion of crop residue came from cereals, followed by sugarcane. In the same study, the latent energy from rice straw (486,955 megawatts) and cereals (226,200 megawatts) was evaluated [14]. Recent studies have continued to highlight these challenges and explore potential solutions. For instance, new technologies and sustainable practices for managing crop residues are being investigated to mitigate the adverse environmental impacts and enhance bioenergy production [15]. Additionally, innovative policies and farmer education programs are being implemented to promote better waste management practices and reduce the harmful effects of residue burning [16].

1.2 Agricultural residue burning and air pollution

Indo-Gangetic plains of the India region was observed for seventeen air quality parameters, while burning the crop residue the ambient atmospheric levels of PM10 (196.7 ± 30.6 μgm−3), PM2.5 (148.2 ± 20 μgm−3), and PM1 (51.2 ± 8.9 μgm−3) was recorded frequently on 24 h standard base. The highest amount of PM2.5 was recorded in Amritsar (178.4 ± 83.8 μgm−3), and the least concentration was noticed in Chandigarh (112.3 ± 6.9 μgm−3). Besides, the highest concentrations of gaseous pollutants (nitric oxide, oxides of nitrogen, nitrogen dioxide, and sulphur dioxide) were observed at Amritsar locations and noticed generation of secondary pollutants [17]. In India, 48% of total straw residue comes from Haryana and Punjab agricultural fields, to manage this straw in-situ burning is a common option for local farmers but it emits harmful gases into the atmosphere and caused adverse health effects on humans moreover it triggers global warming. An experimental study estimated, burning of 1 metric tonne of straw residue emit 03 kg (Kilograms) of particulate matter, 60 kg carbon monoxide, 1460 kg carbon dioxide, 199 kg ash, and sulphur dioxide 2 kg [18]. Rice and wheat are the common cultivable crops in Haryana, Punjab, U.P, and Rajasthan regions, intensive crop residue burning leads to loss of organic carbon 3850 m/kg, N 59 m/kg, P 20 m/kg, and K 34 m/kg. Besides, the ambient air is polluting with carbon dioxides, methane, nitrogen oxides, sulphurous oxides, and a huge amount of PM10 and PM2.5 which cause significant health effects on humans [19]. In north-western parts of India crop residue blazing is one of the major reasons for increasing pollution in the capital region of the country (Delhi), satellite (GIS) and the ground-based study was explained the pollution level in Indo-Gangetic plains, pointed the increasing risk of tiny carbon fleck and Green house gases (GHGs) in ambient air of the region observed from 2010 to recent years [20]. In-situ agricultural waste burning and carbon dioxide emissions were compared around the world (US, India, China, and Brazil) and the details were projected in the bar chart (Fig. 2).

Fig. 2
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In-situ agricultural waste burning and carbon dioxide emissions were compared around the world

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1.3 Air pollution estimation models and effect on human health

In north-western India, management of produced crop residue in rice–wheat farming systems within a short window period (10–15 days), to ready the farmland for timely sowing the next crop is a tough task. Lack of farmer-friendly options about to handle the crop leftover, Haryana, Punjab, U.P and Rajasthan farmers opted in-situ burning, the consequence of this practice emits different pollutants, Soot, NO2, SO2, CO2, CO, and PAHs pollute the Environment, moreover, it caused nutrient to lose in the soils [21]. 2017–18 agriculture year, Punjab and Haryana were assumed that 20.3 and 9.6 megatons of agricultural residue were burned and the emissions were recorded by VIIRS Thermal Anomalies Datasets, result, emission of atmospheric pollutants like PM2.5, PM10, CO2, GHGs, PAHs, and other pollutants raise was observed. It harmed public health in the central capital region of India [22]. Agricultural residue burning was quantified based on spatiotemporal data (MODIS) in Madhya Pradesh, India. Spatial–temporal parameters were observed over the last three years (2022 to 2024), revealing an increased frequency of fire incidents from 1268 to 7915. Among all incidents, 48.1% were identified in croplands and 36% in forests. Residue burning incidents increased tenfold, from 454 to 4359. The burning incidents were more frequent in the Rabi season (March–May) than in the Kharif season (October–December). This information was used to project long-term evolution studies for sustainable agricultural residue burning [23]. In north-Indian states like Punjab, Haryana, U.P, Rajasthan to manage the crop residue in their agriculture fields, practice intensive open burning in pre-post monsoon periods, it releases and added significant amount of particulate matter in the atmosphere. Winter seasons in Delhi form air-locked conditions result in poor air quality in the national capital region [24].

Indian agricultural domain responsible for the generation of 22,289 gigagrams of paddy residue per Annam, and total content of it 13,915 gigagrams (62.42%) of paddy stubble sets under fire in the farmlands. Haryana and Panjab produce 48% of countries' total crop residue and it exposed to burn in-situ, thus various harmful gases emit into the atmosphere and damage human health such as pneumoconiosis, pulmonary tuberculosis, bronchitis, blindness, cataract, pulmonary diseases, and corneal opacity [25]. Laboratory simulations were estimated for PM2.5, rice, wheat, and maize crop residue exposed to burn and characterized the PM2.5 particles, EC, PAHs, and APAHs, these pollutants lead to visibility impairment in humans [26].

1.4 Agricultural residue burning and loss of soil nutrients

Crop residue (rice straw) burning to damage the beneficial soil microorganisms, and nutrient loss was observed in Haryana, Panipat crop field [27]. In-situ crop waste burning affects the soil physico-chemical parameters, raise in pH and EC of the soils was noticed, before burning soil pH 7.94, EC 245–699 µS/cm and after burning soil pH 8.6, EC 403–800 µS/cm. similarly, increase in soil organic matter 25,200 to 27,100 mg/kg, but nitrogen, phosphorus, and decreased soil digestive enzyme activities [28]. In-situ burning caused soil nutrients loss some analysis results in Haryana and Panjab rice crop fields such as nitrogen (N) 0.236 Mt/yr, phosphorous (P) 0.009 Mt/yr, potassium (K) 0.200 Mt/yr, similarly in the wheat fields soil loss N 0.079 Mt/yr, P 0.004 Mt/yr, K 0.061 Mt/yr and in the Sugar cane fields soil loss N 0.079 Mt/yr, P 0.001 Mt/yr, K 0.84 Mt/yr [29]. To achieve food security, agricultural soils play a key role, due to several reasons, cultivable soils lose their nutritional values and lead to unproductive, to this concern south Asian countries postulated soil management policies for sustainable ecosystem survives [30].

2 Crop residue and livestock management

In developing countries like India, the majority of the population depends on agriculture, livestock management, and dairy production as auxiliary industries within the farming tradition. This interdependence underscores the critical need for efficient resource utilization, including the management of agricultural residues. To maintain the livestock industry, the demand for crude protein (feed) is significant, estimated at 50 to 60% of the country’s total agricultural output. Interestingly, feed availability scenarios recorded on a dry biomass basis reveal that 70% of dry matter comes as a secondary product from grain production [31]. The integration of biochar production into agricultural practices presents a promising solution for managing these residues while addressing energy needs and enhancing soil health.

In regions like Andhra Pradesh, where the dry biomass attainability for different feed resources is 16.93 million tonnes (Mt), 84.4% of total crop residue is utilized for livestock feed [27]. By converting a portion of this crop residue into biochar through pyrolysis, farmers can create a valuable soil amendment that improves soil fertility, increases crop yields, and sequesters carbon, thus contributing to climate change mitigation. Moreover, the pyrolysis process produces not only biochar but also bio-oil and syngas, both of which can be used as renewable energy sources. Bio-oil can serve as a fuel for heating, power generation, or be refined into transportation fuels, while syngas can generate electricity and heat or act as a feedstock for producing chemicals and fuels. This multifaceted energy recovery process ensures that the energy content of agricultural residues is fully utilized, promoting a more sustainable and efficient agricultural system.

The economic benefits of integrating biochar production into agricultural practices are substantial. Farmers can diversify their income streams by producing and selling biochar and energy products derived from bio-oil and syngas. Establishing biochar production facilities can stimulate rural economies by creating jobs and supporting local businesses. Additionally, using biochar to enhance soil health can lead to increased agricultural productivity, further supporting economic stability and growth in rural areas.

3 Agricultural residue and management strategies

Agricultural Ministry (DAC&FW) in 2018–19 assigned a task to Indian Council of Agricultural Research (ICAR) with 21.29 crores funded project, it has been implementing in 60 KVKs in Indo-Gangetic plains, and all of them 22 placed in Punjab, 14 in Haryana, 01 in Delhi and 23 in Uttar Pradesh, KVKs provide training and technology assessment to manage the crop residue [25]. A report was projected different technologies to avoid the agricultural residue burning in Punjab, Haryana, Delhi region and west Bengal, coded technologies were Super straw management system, happy seeder, hydraulic reversible M.B. plow, rotary mulcher, shrub master, paddy straw chopper/shredder (Ministry of Agriculture and Farmers Welfare, 2019). In the north-western parts of India, farmers preferred to burn the leftover in-situ, it pollutes the environment, agricultural fields and involved severe human health risks. Management of the crop residue had a key role in nutrient recycling into the soil, plants, and atmospheric entities. ICAR developed various technologies to manage the crop residue in Indo-Gangetic plains, happy seeder, and super straw management system are sowing spatial zero-till drive, sowing with seed cum fertilizer drill, sowing with rototill drill [32]. To overcome the crop residue burning problem, happy seeder (HS) is one of the most believable options among all of the tillage practices, it saves investment, water, facilitates time for wheat sowing after rice harvesting, and leads to sustainable development [33]. Happy seeders reduce GHGs emission, loss of soil nutrients, and loss of soil micros [34]. Mulching technology introduced by DIHAR in Ladakh and was implemented in low productive tomato crop fields, wheat straw was exposed to various rhizosphere microbial biota covered with plastic film and allowed the crop growth. The height concentrations of phosphorus, Potassium, Magnesium, and micronutrients (Fe, Mn, and Cu) were noticed in crop plants by ICP-OES analysis [35]. Excessive tillage may damage the productivity of the farmlands, in China, winter wheat crop soil health and root ecology were tested with various tillage practice with sub-soiling interval (two-years), observed lower bulk density, changed root characters, high indole acetic acid, and more absorption root surface [36]. Machinery in agriculture and its sustainable aimed designs to manage different agricultural tasks and crop residue management, it reduces time, cost, and effort in agriculture fields, the machinery intervention in farm field leads towards sustainability in agriculture development [37]. Agricultural crop waste (wheat residue) is used as supporting material for decomposition food waste, the maggot larvae in the presence of garbage enzyme decomposed the food waste effectively, and significantly reduced heavy metal concentration was recorded in prepared compost [38].

3.1 Agricultural residue production—inherent energy

Agricultural residue production plays a significant role in the energy sector, particularly in a country like India where agriculture is a major part of the economy. Crop residues such as rice straw, wheat straw, and corn stover are often underutilized or poorly managed, leading to environmental issues like pollution from in-situ burning. However, these residues hold considerable potential for energy recovery through processes like anaerobic digestion, which can effectively convert biomass into methane, a renewable energy source. This method not only provides a sustainable way to manage agricultural waste but also reduces greenhouse gas emissions, contributing to a cleaner environment [39]. Recent advancements in biofuel technology have emphasized the importance of converting agricultural residues into bioenergy. For instance, sugarcane bagasse, maize stalks, and rice husks can be transformed into biofuels, offering a renewable alternative to fossil fuels and alleviating pressure on natural resources [40].

The Indian context is particularly noteworthy, with an estimated 370 million tonnes of biomass produced annually. This biomass has the potential to generate up to 17 GW of energy, highlighting the substantial opportunities for sustainable energy production in the country. In Haryana alone, an agricultural state, 24.697 million tonnes of crop waste are produced each year, with a significant portion being utilized for various purposes. The surplus biomass, which could generate an additional 1.499 GW of energy, underscores the untapped potential in the region [41]. Efforts to curb the in-situ burning of paddy residue in states like Punjab and Haryana have led to initiatives aimed at promoting biomass-based power plants. A survey conducted in these regions indicated strong support for such projects, as they not only provide a sustainable solution to waste management but also boost the local economy. Establishing biomass power plants can enhance the economic status of farmers, create employment opportunities, and offer skill development training to the local population [28]. These developments are crucial in the transition towards a more sustainable and eco-friendly energy system, leveraging agricultural residues as a valuable resource.

Recent studies have highlighted the vast potential of agricultural residues in India for energy production. For instance, the Indian government has been promoting schemes to encourage the utilization of agricultural residues for bioenergy. The National Policy on Biofuels and the National Biomass Mission are pivotal initiatives aimed at enhancing the use of biomass for energy generation. These policies are designed to support the development of biomass power plants and incentivize farmers to supply crop residues for energy production. Moreover, advancements in technology have improved the efficiency of converting agricultural residues into bioenergy. Techniques such as pyrolysis, gasification, and fermentation are being refined to optimize the yield and quality of biofuels derived from agricultural waste. Pyrolysis, for example, involves the thermal decomposition of biomass in the absence of oxygen, producing bio-oil, syngas, and biochar, which can be used as renewable energy sources. The integration of agricultural residue-based bioenergy into India's energy mix can also contribute to reducing greenhouse gas emissions. The use of biofuels derived from crop residues can significantly lower the carbon footprint compared to conventional fossil fuels. This aligns with India's commitments under the Paris Agreement to reduce carbon emissions and transition towards a low-carbon economy.

Furthermore, the socio-economic benefits of utilizing agricultural residues for energy production are substantial. The establishment of biomass power plants in rural areas can create job opportunities, stimulate local economies, and reduce poverty. Farmers can earn additional income by selling crop residues, and communities can benefit from improved energy access and reduced dependence on imported fuels. In addition, addressing the issue of crop residue burning through biomass power generation can improve air quality and public health. Crop residue burning is a major source of air pollution in India, contributing to smog and respiratory problems. By providing an alternative use for crop residues, biomass power plants can help mitigate these adverse environmental and health impacts. The role of research and development in advancing the utilization of agricultural residues for energy cannot be overstated. Continued investment in R&D is essential to develop more efficient and cost-effective technologies for biomass conversion. Collaborative efforts between government, industry, and academia can drive innovation and accelerate the adoption of sustainable bioenergy solutions.

4 Agricultural residue and energy recovery technologies

Rice straw and other crop residue used as a substrate for fabricating bioethanol, biochar, fuel-pellets, fuel-briquette, compost, animal feed, and eco-panel [42]. The fast depletion of energy resources and changes in climate warming phenomenon was driven to practice the circular environmental management concepts, to explain renewable energy resource role and management of waste (municipal, electronic, and plastic) relations among circular economy and sustainable development policies. It majorly focused on energy recovery technologies from the waste integrated with sustainable practices [43, 44]. The hierarchy of the crop residue management and energy recovery technologies were mention as biogas production, biochar preparation, and bioethanol production). Biowaste-to-energy is the best practice for sustainable development, India producing a significant amount of organic waste, to recover the energy from the waste various technologies were developed and adopted, moreover, realistic problems were projected [45]. Several eco-friendly technologies are available to handle the huge crop residue in the agricultural fields, some are effective to implement and some are under progressive development to reach the sustainable mark demands (Fig. 3).

Fig. 3
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Several eco-friendly technologies available to handle the huge crop residue in the agricultural fields

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4.1 a. Biogas production

Punjab producing a huge amount of biomass and it was the estimated highest energy-producing (3172 MW) state in India. Currently, Bio-CNG producing from biogas, India was in search for conversion of biogas into electricity practices, Punjab has massive chances to establish decentralized biogas plants for producing biogas to electricity due to availability of the enormous amount of agriculture, animal, and household waste. Biogas production is one of the most preferable and promising technology in the context of crop residue management, current policies and research support not enough to reach the needs of efficient energy recovery from the residue, it demands, improve the effective anaerobic digestion technologies to convert the agri-waste to circular economic aspects. Vegetable and other agricultural residues were collected in Maharashtra, examined the substrate availability for the anaerobic digestion (AD), and coded that biogas (methane) quality depends on the composition of the used biowaste for digestion [46]. Rajasthan producing a large quantity of wheat and millet residue (straw), tested for the production strategies on biogas by giving pre-treatment with lime (Ca(OH)2) at different temperature profiles and observed that raise in biogas production. Agro-residue is used in mushroom cultivation, fungi digest the crop residue and produce food, fungal metabolism useful as pre-treatment and form spend mushroom substrate, by adding other residues biogas production rate was increased significantly [47, 48]. Rice straw mixed with municipal solid waste in three various ratios and allowed them into co-digestion, the highest amount of biogas production was noticed in 2:1 ratio and 60% biogas potential increase was noticed in the same ratio, moreover, C/N ratio optimization was noticed.

4.2 b. Biochar preparation

Biochar production merits inclusion under a section titled "Energy Recovery Technologies" because the process of producing biochar, typically through pyrolysis, is intrinsically linked to energy recovery. Biochar preparation is one of the eco-friendly options to manage the crop residue, it increases soil fertility, soil carbon sequestration, and enhances crop production, slow pyrolysis of the rice husk at 650 ℃ and maize stover at 550 ℃ were responsible for the production of biochar. Compared to the biochar and un-pyrolyzed rice husk in various agricultural soils, then recorded an increase in different soil parameters and a decrease in CO2 emission was notices [49, 50]. Conversion of crop residue into biochar through pyrolysis is an effective solution for the management of agricultural waste [51]. A thermochemical conversion technology was developed for continuous manufacturing of biochar, groundnut shell was treated at various temperatures for carbonization, different crop residues were converted into biochar through this technology, and the production efficiency of biochar was noticed 30% [52]. Pyrolysis, carbonisation, gasification, hydrothermal, and torrefaction were different methodologies for biochar production, the property of the synthesized biochar depends on waste residue type and chemical composition, pyrolysis set-up temperature and time determine the quality of biochar [53, 54]. Biochar made with cotton residue composed of the highest carbon concentration and the biochar prepared with rice straw contains the highest amount of nitrogen and oxygen [55]. One hectare cotton farm field is estimated to produce 130 kg biochar per year [56]. The burning of agricultural residue caused changes in soil physical, chemical, and biological parameters of croplands. An observation was recorded instead of residue burn the raw mulch and prepared biochar employed into the field enhanced the soil yield capacity (36%-64%) in the tested lands of south Asia [57].

4.3 c. Bioethanol production

Energy crisis and its present demand became one of the major fundamental problems around the globe, production of bioethanol mandated in developed and developing countries, current policies in India no specific time goals to achieve successful bioethanol extraction to reach its future sustainability and economic feasibility in the bioethanol market of India.

Presently, bioethanol production in India depends on sugarcane molasses, but it is not enough to reach the production targets. Therefore, excess crop residue is used as a substrate to produce bioethanol (second-generation biofuels) to satisfy energy needs [58]. Pre-treatment had a vital role in the production of bioethanol, recent advanced technologies were integrated with pre-treatment principles towards a sustainable bioethanol market. Rice straw treated with 2% v/w NaOH and employed for enzymatic saccharification, T.reesei NCIM 1052 produced high fermentable sugars (55.6 g/l), higher ethanol (25.3 g/L) concentration was noticed in P.stipitis NCIM 3499, and it explained maximum significance for economic production of bioethanol from rice straw [59]. Sesame plant biomass was used to produce bioethanol, 1.90 g/L yield was observed after 60 h of fermentation. Lignocellulose feedstock like sugarcane, rice straw, maize, and millet residues were pre-treated (hydrolysis) with dilute acids, allowed to fermentation at 27 ℃ in the presence of biocatalyst (white-rot fungus). The result of the enzymatic hydrolysis was great and constant, 85 to 90% of fermentable sugars transformed into bioethanol [60]. Mostly two technologies were used for the production of bioethanol which is biological and thermochemical conversions, major principles involved in bioethanol production pre-treatment, enzymatic hydrolysis, fermentation, distillation, and filtration these made the technologies economically feasible [61]. Bioethanol is reviewed as one of the alternative fuels for future demands, presently 5% of the ethanol produced from motor gasoline, other technologies depend on lignocellulosic treatment are not completely developed for bioethanol production. A significant amount of bioethanol production capacity was estimated from cereal crop residue, Genome editing and metabolic engineering technology is the advanced practices for bioethanol production, these increase bioethanol yield and facilitate biorefinery theme [62].

4.4 d. Compost preparation

Vermicomposting is an economic and eco-friendly technology, earthworm Eisenia foetidade composed the agricultural residue at 20 to 35 ℃ temperature along 60 to 80% relative humidity and produce a nutritional source of bio-fertilizer. Vermicomposting technology brought changes in compost physico-chemical parameters; it results in, decrease in TOC and C/N ratio but at the same time it showed an increase in NPK concentrations. Prepared vermicompost act like biocontrol for pathogens, it improved water holding capacity and supported for high yield [63]. Compost preparation in vermicomposting technology triggers useful changes in the compost; such as physico-chemical parameters, biological characters, and biochemical properties. Earthworms feed and digest the waste and reduce toxic elemental concentrations of the compost [64]. It can be effectively converted the lignocellulosic waste into a higher national value biofertilizer by employing the earthworms (Eisenaiafetida) on lignocellulosic waste [65]. Disposal of flower waste in rivers and landfills causes water and soil pollution, in this view, the flower residue mixed with cow dung and sawdust allowed it for central composting. The addition of cow dung maintains the maturity and the sawdust to hold the leachate, facilitate aerobic digestion and lump formation, resulted in compost was good for plant growth [66]. Vermicompost prepared from different crop residues like coconut, banana, cassava, teak, and some other weed plants, recorded the prepared vermicompost efficiency as greater than 60% remains the amount of carbon was lost in decomposition, respectively, rubber plant waste and mango crop residue produced greater than 20% efficient vermicompost, similarly, banana plant waste, jack fruit plant waste, coconut, and cocoa compost was recorded greater than 50% efficient [67, 68]. By composting the crop residue nutrients can be reunited into the soils [69]. Rice straw is mixed with another waste residue along with the cow dung in different proportions, it has undergone decomposition by the earthworms around 105 days and the resulting compost was enriched with a high amount of nitrogen, phosphorus, and potassium were observed, the increase of heavy metal concentrations in prepared vermicompost [70, 71]. Scanning Electron Microscopy was developed to record the C/N ratio and maturity of the prepared vermicompost, rice straw mixed with Azolla, and fungus in presence of cattle dung, it facilitated the fastest stabilization of the rice straw compost [72].

5 Conclusion

The study highlights the significant impact of agricultural residue burning on air quality, soil health, and human health in India, particularly in the Indo-Gangetic plains. The frequent in-situ burning of crop residues, especially rice and wheat, contributes to high levels of particulate matter (PM10, PM2.5, and PM1) and gaseous pollutants (NOx, SO2, CO2) in the atmosphere. This practice not only deteriorates air quality, causing severe health issues but also results in substantial nutrient loss in the soil, affecting agricultural productivity. The current methods for managing crop residues, such as burning, are not sustainable and pose environmental and health hazards. To address these challenges, various management strategies and technologies have been proposed and implemented, including the use of machinery like happy seeder and super straw management system, biogas production, biochar preparation, and bioethanol production. These methods offer promising solutions for sustainable crop residue management, reducing environmental pollution, and enhancing soil health. Additionally, technologies like vermicomposting and compost preparation from crop residues provide eco-friendly alternatives for nutrient recycling and soil enrichment.

6 Future scope

Technological advancements: Further research and development in advanced technologies for crop residue management, such as improved biogas production techniques, efficient biochar production methods, and enhanced bioethanol production processes, are essential. Innovations in these areas can make these technologies more economically viable and widely adoptable by farmers.

Policy implementation: Strengthening policy frameworks and providing incentives for adopting sustainable crop residue management practices are crucial. Government support through subsidies, training programs, and awareness campaigns can encourage farmers to shift from traditional burning methods to more sustainable alternatives.

Integration of renewable energy: Expanding the use of crop residues for renewable energy production, such as biogas and bioethanol, can contribute to energy security and reduce dependency on fossil fuels. Establishing decentralized biogas plants and biomass-related power plants in agricultural regions can create employment opportunities and enhance the local economy.

Sustainable agriculture practices: Promoting sustainable agricultural practices that minimize residue generation and maximize nutrient recycling is vital. Techniques like zero-tillage farming, crop rotation, and organic farming can reduce the need for residue burning and improve soil health.

Health impact studies: Conducting comprehensive studies on the long-term health impacts of agricultural residue burning on local populations can provide valuable data for public health policies. Monitoring air quality and health outcomes can help in devising strategies to mitigate adverse effects.

Global collaboration: Collaborating with international organizations and countries facing similar challenges can facilitate knowledge exchange and adoption of best practices. Joint research initiatives and funding opportunities can accelerate the development and implementation of sustainable residue management solutions.

Community engagement: Engaging local communities and stakeholders in the planning and implementation of crop residue management strategies is crucial for their success. Farmer participation in decision-making processes and adopting community-based approaches can ensure the sustainability of these initiatives.