Introduction

Since 2000 BC, human civilization has progressed by using fossil fuels, where every organism sustaining is forced to depend on energy. Many generations have passed, yet the question remains “a subsequent source for energy production” (Lee and Holder 2001). Anthropogenic indulgence is the prime cause of climate change, converting wetlands into the civil area, population rise, deforestation, burning of fossil fuel, transportation, greenhouse gas emissions (GHGE), and mining (Turner et al. 2019; Kühmaier et al. 2022). Among all other issues, burning fossil fuels also (Stewart et al. 2021) has a significant negative impact on the environment by emitting 25% of greenhouse gas (GHG) and climate change (Massar et al. 2021), which is paramount to all beings and makes plant earth unfit for survival (Ejiofor 2019).

Chief gases commanding to take quick action against drastic climate changes are CO2, CH4, N2O, and fluorinated gases. The present study mainly focuses on the primary greenhouse gases, CH4 emissions rates, and concentration levels. When CO2 is emitted into the atmosphere, 40% remains for 100 years, and 20% remains for 1000 years than other gases like CH4 and nitrous oxide (over a century) (Global Warming Potential 2022). CH4 is the second most significant greenhouse gas in heat-trapping in the atmosphere. The primary sources of CH4 emissions include agriculture, waste, fossil fuels, wetlands, freshwater systems, and geological sources. Wetlands comprise 30% of the total, while agriculture, waste disposal, livestock, oil, gas, and coal mining comprise 20%. Wildfires, biomass burning, and the ocean are other culprits (Jackson et al. 2020; Rosentreter et al. 2021). Likewise, boreal lakes and ponds produce two-thirds of all natural CH4 emissions above latitude 50 North (Martin et al. 2021). By the end of the twentieth century, climatic types near the global mass of 31.3–46.3% will transition from 3.5 to 8.5 RCP (Representative Concentration Pathway) due to significant temperature rise, causing the disappearance of global climate heterogeneity (Zhang et al. 2021). In August 2020, the international team of scientists from Berkeley Lab, including William Riley (senior scientist) and Qing Zhu, estimated global CH4 emissions had increased by nearly 5% from 2008 to 2017, which is 570 million tonnes (Global Carbon Project 2020).

However, it has been noted that CO2 and CH4 emissions vary with biome and physio-hydric variables of soil, temperature, vegetation, water level, and wetland salinity, which significantly impact the rates of CO2 and CH4 emissions (Olsson et al. 2015). Wetlands are a beneficiary source of organic carbon stores, where 15% is released into the atmosphere. About 100–231 Tg (25–40%) of CH4 is released annually from wetland sources (Pugh et al. 2018; Li et al. 2016). Still, our role in the environment is to consider emerging global issues that could get converted into beneficial outcomes without disturbing the regular regulative cycles of the domain (Neale et al. 2021). This review highlights critical themes on CH4 emissions, climate change, and regulatory ecology in methanogenesis, emphasizing CH4’s sustainable use in industrial and energy production for a better future.

Prime sources of CH4 emissions

CH4 emission from wetland

Wetlands are significant ecosystems that maintain the environment’s biodiversity and regulate hydrogeographic basins (Taillardat et al. 2020). Soil is the universal habitat for most organisms, and the bio-geo cycle changes based on vegetation and soil locality (France et al. 2022). These ecosystems support endemic species diversity and contribute to CH4 emissions through topological conditions (Ribeiro et al. 2020; Singh et al. 2018a, b). Wetlands are significant CH4 emitters due to fluctuations in greenhouse gas efflux and changes in genera and vegetation (Baker-Blocker et al. 1977). The deep-down anoxic condition in wetlands leads to the accumulation of humic acid, creating an environment for carbon sequestration. The diverse biome from higher to lower range at each level concerning temperature variation is shown in Fig. 1. The sequestered carbon overweighs CH4 production in non-vegetated areas (Laanbroek, 2010).

Fig. 1
figure 1

Schematic representation of the interconnective and diverse biome from higher to lower range at each level concerning temperature variation (Rothschild and Mancinelli 2001)

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Fluctuation in organic matter affects the vegetative structure of wetlands, leading to increased CH4 emissions with rising temperatures (Kandel et al. 2019). The water table determines the anoxic/oxic and redox boundaries, the primary cause of greenhouse gas emissions. Shallow water levels increase CH4 emissions compared to deeper groundwater, emitting a high magnitude of N2O (Prananto et al. 2020). An increase in CO2 emissions was observed during the growing seasons (spring–fall) at Tibetan plateau peatlands (Cao et al. 2017; Mwagona et al. 2021). Most wetland plant roots have aerenchyma tissue that helps uptake oxygen supply and act as CH4 conduits (Korrensalo et al. 2022). Vascular plants in natural and restored vegetation contribute to CH4 production and consumption (Zhang et al. 2022a, b; Wilson et al. 2016; Van der Nat and Middelburg 2000).

CH4 emissions from the dams

Dams are built to conserve water for irrigation and meet human needs, but their impacts are often debated. The uncontrolled rise in population has led to the construction of reservoirs, which can increase water consumption (Jarveoja et al. 2016). Dams also promote various activities, such as electricity generation, flood control, fish farming, fire protection, erosion prevention, and mine tail storage (Fig. 2a). There is a direct link between CH4 eviction and accumulated organic matter in dams. The deposited organic matter involves trapping CH4 (Fearnside and Pueyo 2012; Varis et al. 2012). Deep under the water column in the dam, due to a lack of agitation and air supply, sediment gets deposited at the bottom (Maeck et al. 2013). Therefore, it serves as a hot spot for anaerobic decomposition biological mechanisms. Thereby, CH4 is released directly into the atmosphere and does not decrease over the dam’s lifetime (Chen et al. 2011). Though it serves as green energy in its prime aspect, it later serves as a significant GHG-releasing factor that considerably impacts the environment (Fearnside and Pueyo 2012; Rooney-Varga et al. 2018).

Fig. 2
figure 2

Prime sources of methane emission. a Dam—decomposition of the accumulated organic matter at the bottom of the reservoir (Lima et al., 2008; Maeck et al. 2013; Song et al. 2018; Seo et al. 2014), b anaerobic condition provided by water flooded farming land (Poppe et al. 2021; Legg et al., 2015), c CH4 emission from upland trees through the interaction between the tree and the soil microbiome (García-Palacios et al., 2021; Korrensalo et al. 2022; Barba et al. 2019), and d ruminant microbiome involving in the digestion of the carbohydrates intake (Mizrahi et al., 2018; Glasson et al. 2022)

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Converted peats for human subsidence

Peatlands, covering nearly 3% of the global landmass, have become a hotspot for CO2 emissions due to anthropogenic disturbances in Northern and Southeast Asia. Southeast Asia, including Malaysia, East Sumatra, Indonesia, and New Guinea, was once considered the largest peatland carbon pool (Lupascu et al. 2020). However, expansion for economic development has led to catastrophic fires, releasing additional carbon into the atmosphere (Xu et al. 2019). The CH4 efflux in fire-affected peatland is higher than in intact peat (Dommain et al. 2018). In contrast, the other peatlands, covering Europe, America, and Russia, account for one-third of the global carbon soil pool. By 2015, 30% of peatland was converted for palm and acacia plantations, lowering water table levels (Jarveoja et al. 2016). Southeast Asian drained peatland generates around 380–420 Tg of CO2 per year, while 44% of carbon emissions from industrial plantations have been reported (Miettinen et al. 2017; McCalmont et al. 2021) as depicted in Fig. 2b. The heating of peat accelerates CH4 emissions during seasonal changes (Joabsson et al. 1999; Wilson et al. 2016).

The rise in population around South Asian countries, including China and Korea, led to the conversion of paramount peat to paddy fields, the staple diet of the significant population (Seo et al. 2014). The metamorphosis of peatland inverses its role in the environment by taking a positive side (global warming) for climate change (Ribeiro et al. 2020; Lynch et al. 2021). At the same time, draining peatlands for human settlement, cultivation, and forestry accelerated CO2 emissions following years in the atmosphere (Krause et al. 2021; Kandel et al. 2019). However, converted peat for paddy cultivation reports 30% of annual carbon storage, referring to their tremendous impact on massive carbon sinks on the millennial scale (Ghazouani et al. 2021). Exploiting natural wetlands threatens the primary hydrological and environmental conditions (Zou et al. 2018).

According to the Fifth IPCC report, agriculture practices alone contribute 38% to global CH4 emissions, with sub-tropical regions like South East Asia, Central and Latin America, and Africa converting most peatlands for paddy cultivation (Rahman et al. 2021; Nie et al. 2019). Improper drainage and converted peatland may evict CH4 in a large proportion to non-paramount regions (Luta et al. 2021). India and China are the primary rice cultivators, with 2600 million people (60% Asians) relying on rice in their diet (Rahman and Yamamoto 2020). Paddy fields, covering 167.25 million hectares globally, account for about 530 Mt of CH4 emissions annually (Ito 2015). Human activities accelerate 60% of CH4 emissions, with 78% of CH4 emitted globally from irrigation paddy fields (Mujiyo et al. 2017). CH4 reacts with the rhizosphere or oxidizes in the oxic region, causing some to get trapped in soil and evicted into the atmosphere. The average mixing ratio of CH4 in the atmosphere has increased by 6.8 ppb in the last decade. Still, the cascade releases CH4 into the environment, causing it to linger in the atmosphere for an extended period, as per World Data Centre for Green House Gases (WDCGG) survey (World Meteorological Organization 2019).

Trees’ role in CH4 emissions

Trees play the frontier role in balancing the geo cycle in the atmosphere. Recently accelerated CH4 emissions from trees into the atmosphere are at an alarming venue in global warming (Jeffrey et al. 2021). Intact and dead trees participate in CH4 sequestration and eviction in the environment. An incredible amount of CH4 gets loaded in upland trees, where more than 65% gets trapped in tree stems. CH4 in the tree was first reported in 1970 by Bushong while cutting cottonwood trees (Flanagan et al. 2020). The heartwood of the stem accumulates 250,000 times more CH4 than the balanced atmosphere, but the high accumulation of CH4 in the heartwood does not relate to the total CH4 efflux rate (Barba et al. 2019). The flux dynamic depends on internal and physical factors like species, ages, tissue type, site characteristics, and environmental conditions and primarily on stem water content controlling gas diffusion rates (Covey and Megonigal 2019), as depicted in Fig. 2c. Comparatively, CH4 emissions from upland trees are lesser than from wetland trees. In wetlands or uplands, living trees emit more CH4 than dead ones, regardless of the physiochemical conditions (Pitz and Megonigal 2017). It proves tree stems are the source or sink co-related to (methanogenesis) production and CH4 consumption (methanotrophs). CH4 is produced deep inside the layer of soil and then released into the atmosphere through roots, stems, and leaves (Wang et al. 2017; Li et al. 2020).

Three trillion trees are present worldwide, considering the CH4 kinetics from individual trees could upscale the overall global flux (Barba et al. 2019). The tree stem embellishes 1–6% of accumulated CH4 in the soil, changing the upland sink into a source of efflux. Thus, the flux between upland and tree stem makes it difficult to maintain the forest temperature uniform (Pitz and Megonigal 2017). In addition, diseases like fungal infection in plants generate a CO2 environment favouring the growth of anaerobic organisms (minor redox condition), selecting the methanogens survival. Epiphytes such as algae, lichen, bryophytes, and cyanobacteria in the tree bark help maintain the tree stem’s CH4 emissions (Lenhart et al. 2015). The consequence of regulative factors involved in climate change and global warming must be concerned to understand the bio-geo cycle flux.

Ruminants’ role in CH4 emissions

As other sources contribute to CH4 emissions, anthropogenic is no less equal (Misiukiewicz et al. 2021; Sharma and Sinha 2013). Due to the increasing population, the need for meat and meat products will rise to 70–78% by 2050 (Min et al. 2020; Tseten et al. 2022). The rumen ecosystem plays a 90% function in digesting complex plant materials. The feed degradation and release of CH4 from ruminants are considered a vast complex biome interaction globally (Mizrahi and Jami 2018). Among other products, CH4 is produced at a comparable rate in ruminants (95%) and nonruminants (5%) by digestion (Zhao and Zhao 2021). The anaerobic digestion of carbohydrates in ruminants’ gastrointestinal tracts produces CH4 as they are being digested (Lan and Yang 2019), as picturized in Fig. 2d. These anaerobic archaeal methanogens convert the single carbon source to CH4 using a straightforward oxidation process.

Ruminants undertake three modes of the process such as (i) CO2-H2 conversion, (ii) transformation of fatty acid chains like acetic acid, formic acid, and butyric acid, and (iii) synthesis of compounds like methanol and ethanol for degrading the feed (Lan and Yang 2019). Most methanogens undergo (a primary pathway) to reduce CO2 to CH4 in the rumen. Ruminant CH4 release accounts for about 19% of global CH4 emissions (Sun et al. 2021). The industry’s continued growth, the cost of mitigation, the difficulty of implementing mitigation measures for grazing ruminants, the inconsistent effects on animal performance, and the scarcity of data on animal health, reproduction, product quality, cost–benefit, safety, and consumer acceptance are significant obstacles to reducing global enteric CH4 emissions from ruminants (Beauchemin et al. 2020).

Anthropogenic factors adding to CH4 emissions

Anthropocene-humans’ inference in the environment leads to potential global warming (PGW), with unhealthy events like burning fossil fuels and deforestation accelerating greenhouse gas (GHG) emissions (Feng et al. 2022). GHGs disrupt the Earth’s carbon cycle, including water vapour, CO2, CH4, N2O, and radiative fluxes. Since industrialization began in 1900, GHG emissions have increased over time (Ritchie et al. 2020a, b). NASA warns that clearing forest areas has significantly impacted climate change. Human-caused sources of CH4 emissions include agriculture, livestock, fossil fuel extraction, energy generation, coal mining, biogas and oil frameworks, waste treatment, and disposal (Zheng et al. 2021; Kulkarni et al. 2022). As the population grows, there is a growing demand for food, such as rice and ruminant livestock, which directly contribute to CH4 emissions (Jorgenson and Birkholz 2010). In 2020, up to 60% of CH4 emissions from these sources were recorded in the atmosphere (Staniaszek et al. 2022).

CH4 emissions from oil and gas production and transportation significantly contribute to climate change. Wells leaking CH4 can increase the risk of explosions, pollute groundwater, alter air quality, and release harmful aromatic compounds like benzene and toluene, which harm human health (Lebel et al. 2020). In Canada and the USA, CH4 emissions from abandoned wells account for 150 times, and 20% of world emissions were reported by Williams et al. (2021). In 2022, 43% of CH4 emissions were due to anthropogenic activity. China has risen to third place in energy consumption since 2013, consuming 8.3% more natural gas than in 2000 (Wang et al. 2022). If CH4 leaks into the atmosphere, it has the same greenhouse gas effects as CO2 molecules, a drawback of biogas production (Torres-Sebastián et al. 2021). Pieprzyk and Hilje (2018) predicted that global CH4 emissions from the oil industry in 2015 would reach 22 to 59 Mt, with crude oil CH4 emissions rising from 18 to 59% by 2040. They calculated those global emissions from venting (52%), incomplete combustion during flaring (1.4%), and fugitive emissions (42%) from diesel and petrol ranged from 8.78 to 14.80 g CO2eq MJ-1 to 8.88 to 16.34 g CO2eq MJ-1 in 2040. However, recent inventory estimates do not account for frequent escapes of substantial amounts of CH4 during maintenance operations or equipment failures. Upstream production processes are the leading causes of oil and gas CH4 emissions.

Landfills release more CH4 into the atmosphere than previously thought, ranking third, followed by oil and biogas systems and agriculture (Singh et al. 2018a, b; Nguyen and Lee 2021). These emissions were mainly generated through microorganisms’ anaerobic breakdown of organic matter (Dang et al. 2023). The two significant greenhouse gases landfills release are CH4, CO2, N2O, carbon monoxide, and hydrochlorofluorocarbons (CFCs, HCFCs, and HFCs) are trace components that make up essential greenhouse gases. CH4 burns to produce greenhouse gases like CO2, water vapour, and ozone and filters outgoing radiation. Landfilling gas emissions contribute 50–99% to global warming, ozone depletion, and smog impacts (Wang et al. 2021a, b). According to a recent analysis by the International Energy Agency, China, India, and Russia are the world’s largest CH4 polluters (Manheim et al. 2021).

Additionally, despite the transition to clean energy, coal plays a crucial role in the world economy (Warmuzinski 2008). Coalification converts biomass into coal through biological and geological processes, releasing CH4 gas and coal. When pressure within coalbeds is lowered due to faulting, natural erosion, or mining, CH4 is released (Dutka and Godyń 2021; Li et al. 2022). Commercial extraction of coalbed CH4 (CBM) has been ongoing for over 60 years (Wang et al. 2021a, b). Mine gas emissions from coal mines contribute 7% of global CH4 production but can also come from thermogenic and biogenic sources (Beckmann et al. 2011; Kholod et al. 2020). It also contributes to the depletion of the ozone layer and has a positive ecological impact by enhancing warming. CH4 from coal extraction can be used for electricity or commercial purposes (Ianc et al. 2020; Yang et al. 2021). However, CH4 concentrations increased 2.5 times from 731 ppb in 1750 to 1890 ppb in 2020 (Nisbet et al. 2019).

Development towards destruction

Over the years, Earth’s climate has been estimated based on physical, chemical, and biological complex ocean, land, and atmosphere processes. The radiative property of the atmosphere, a significant climate-changing factor, is strongly affected by the Earth’s surface biophysical state and trace constituents, which act as an amphipathic radiative energy response (Specht et al. 2016). In addition, it is supported by atmospheric changes through anthropogenic emissions of GHGs like CO2, CH4, and N2O and aerosols and volcanic eruptions (Menon et al. 2007; Xie et al. 2016). However, the mean annual increase of CO2 is 2.40 ppm and CH4 is 8.0 ppm per year. As per the 2021 IEA record, among other countries, India releases about 16% CH4 from the energy sector and 8.9% (31842 kt) of total emissions (International Energy Outlook, Global Methane Tracker 2022).

CH4 has a potential for global warming that is 80 times greater than CO2 over 20 years and 34 times greater over 100 years (Wang et al. 2022). Naturally occurring global bio-geo cycle are incrementally and constantly affected by human activities. According to the WDCGG survey in 2020, the net global mean abundance of CH4 is 1889 ± 2, an 11 ppb increase between 2019 and 2020. According to the methane emissions tracker 2022, CH4 emissions from energy sources are about 70% more than anthropogenic sources estimate (International Energy Agency, Global Methane Tracker, 2022). The development and developing process clearly shows the effect of its destruction, which is not far. So, the CH4 and CO2 emissions efflux must be examined under comparative study in all wetlands to better estimate the threat source (Rousk and Bengtson 2014).

India and China account for 36% of the world population, with India covering 67% of the Asian population. The accelerating population in both countries converts natural land into reclaimed land for irrigation and conservation, becoming a leading carbon source. Irrigation lands account for about 6–7 tonnes (2.4–4.2%) of CO2 annually in the Netherlands (Poppe et al. 2021). According to the COP26 and Paris Agreement reports, developed nations are primarily responsible for the accelerated mission; since the 1850s, the USA has been the top GHG emitter. As per the IPCC-2021 study, the total emissions of CH4 from various sectors show a significant shift in the top-hit countries, as depicted in Fig. 3. China takes the top spot, followed by India, Indonesia, Russia, North America, Iran, and more. As a result, small groups of progressive steps will be adopted to reduce CH4 emissions to 30% by 2030 (Global Climate Agreements: Successes and Failures 2021). According to Our World In Data (OWID) reports, in 2020, CO2 emissions were significant in Asia and China after the twentieth century. Asia is marked as the largest emitter of CO2, accounts about 53%, which is more than one-quarter of global emissions (Ritchie et al. 2020a, b). Compared with top CH4-emitting countries like India, Indonesia, Russia, North America, Europe, and the USA, China recorded the highest emissions (> 50,000 MtC, 2021), as represented in (Fig. 3a; Supplementary Tables S1 and S2). At the same time, China (> 5000 MtC, 2021) and North America (> 3000 MtC, 2021) have taken the first two positions for CO2 emissions from territorial and consumption as shown in Fig. 3b and Supplementary Table S3 (Global Carbon Project 2021; Friedlingstein et al. 2022; Drinkwater et al. 2023). From the last 5 years, data from various sectors taken for fossil fuel, coal, and oil are at the top-hit prime sources reported by Friedlingstein et al. (2020) and Zhang et al. (2022a, b), as represented in Fig. 4 and Supplementary Tables S4 and S5. The present global and historical carbon budget has shifted out of balance (− 0.788, 2020) due to fossil fuel emissions, atmospheric expansion, the ocean, land, and cement sinks (Fig. 5; Supplementary Table S6) (Global Carbon Project 2021; Friedlingstein et al. 2022).

Fig. 3
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Representation of the top most countries emitting methane (a) and carbon dioxide (b) measured in metric tons

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Fig. 4
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The last 5 years of carbon emission in various sectors were measured in MtC/year (Friedlingstein et al. 2020)

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Fig. 5
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Estimation of global and historical carbon budgets from the various source were measured in GtC (Global Carbon Project 2021; Friedlingstein et al. 2022)

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Sustainable resource

Methane is a clean, efficient biochemical and biofuel resource, but backup sources are not scientifically proven, and fossil fuels run out faster (Fan et al. 2021; Liu et al. 2021). CH4 is an excellent fuel for combustion, and CH4 releases less CO2 per mole than any other fossil fuel (Lee and Holder 2001), as depicted in Fig. 6. CH4 is a potent GHG and a more prominent energy source than other resources. Methanogenic bacteria also provide a platform for energy conversion, which can become a future CH4-based bio-manufacture industry (Nguyen and Lee 2021). CH4 produces ammonia, syngas, hydrogen, and methanol without exploiting nature (Richard et al. 2021). Gaseous biofuels reduce GHG emissions and have a high energy consumption value. CH4 can become the principal feedstock for future single-cell protein production, revitalizing rural communities with much access to it (Pieja et al. 2017; Kulkarni and Ghanegaonkar 2019). We are on the brink of a radical technological revolution necessary to protect the environment and its inhabitants (Jones et al. 2022).

Fig. 6
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Production of carbon–neutral fuel—CH4—by CO2-reducing methanogens

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Biology of methanogens

Methanogens produce CH4 to conserve high energy for adenosine triphosphate synthesis (ATPs), thereby marked as a sustainable resource for future energy development (Steinlechner and Junge 2018; Chellapandi and Prathiviraj 2020; Prathiviraj and Chellapandi 2020a; Gao and Lu 2021). It has faked the customary belief that the organism consumes energy for growth and has inspired the study area with its exotic metabolic pathways (Holmes and Smith 2016; Holmes et al. 2019). It plays a significant role in interconnective biome pathways in converting CH4 by decomposing organic carbon dumps (anoxic/reduced condition) (Gao and Lu 2021; Dang et al. 2023). In 1776, Alessandro Volta first discovered the bio-production of CH4 through his experiment on flammable gas from swamps and hypothesized that it is derived from decaying organic matter. Methanogens configure a significant fraction of the Earth’s diversity that controls the global climate conditions (Enzmann et al. 2018). It can be isolated from extreme thermochemical gradients from acidic to alkaline (03.0–12.0 pH) conditions, psychrophilic (1 to 124 °C) to hyperthermophilic (80–98 °C) conditions, and estuaries to hypersaline. The primary spots of methanogens range from deep thermal vents to the digestive tract of animals (Chellapandi et al. 2018). Other harbour methanogen conditions include freshwater estuaries, peat bogs, swamps, and wetlands (Wolfe 1993).

Methanogens are phylogenetically and biochemically distinct organisms that preserve energy through the Wolfe cycle, producing CH4 as a byproduct of their fundamental demand (Buan 2018). The methanogens are classified into the phyla Euarachaeota and are considered the “thermodynamic edge of life.” Methanogens grow autotrophically in sealed glass vials without light, using an inorganic substrate as the sole carbon source. Intermediatory derivatives from methanogens support and create a favourable interconnective biome community (Wang and Lee 2021). Methanogens were distinguished from bacteria and archaea branches with non-methanogenic halophiles, thermoacidophiles, and hyperthermophilic archaea (Prathiviraj and Chellapandi 2020b). The enzyme system, an ancestral feature of archaea and bacteria, has been lost in all but a few lineages of prokaryotes (Juottonen et al. 2006).

The catabolic mechanism divided methanogens into CO2-reducing, methylotrophic, and acetoclastic (Galagan et al. 2002; Juottonen et al. 2005; Prathaban et al. 2017). They need H2 as the sole source of converting CO2 to CH4, where H2 is a commonly released byproduct from other bacteria. As an essential extracellular intermediate, H2 never accumulates as it gets rapidly utilized by other metabolic functions (Ferry 1993). Recently, the phyla affiliating seven orders have been recognized where Methanobacteriale, Methanococcales, Methanomicrobiales, Methanosarcinales, Methanopyrales, Methaenocellales, and Methanomasiliicoccales (obligate methyl-respiring methanogens) in Thermoplasmata (Xu et al. 2021). In terms of their physiology, hydrogenotrophic methanogens evolved 3.5 billion years ago. In contrast, acetoclastic and methylotrophic originated recently, before 200–450 million years but could have lost their CH4-producing ability (Miller et al. 1988; Rohlin and Gunsalus 2010; Adam et al. 2017).

Extraordinary biome interaction

With rapid evolution and extensive adaptative physiology, methanogens seize multiple metabolic pathways. Methanogens are critical in maintaining the geothermal and global energy cycle via methanogenesis. Methanogens produce CH4 using simple substrates such as CO2 and H2 via an anaerobic path (Lyu and Whitman 2019; Chellapandi and Prathiviraj 2020; Prathaban et al. 2017). Methanogens carry out methanogenesis in both forward (hydrogenotrophic) and reversed (methylotrophic) manners as they contain all the genes and enzymes within (Timmers et al. 2017; Prathaban et al. 2017). They maintain the direct interactive electron transfer (DIET) connection with exoelectrogenic organisms concerning their habitat (Mand and Metcalf 2019; Prathiviraj et al. 2019; Prathiviraj and Chellapandi 2019, 2020b). Therefore, indigenous multi-community biome and external environmental conditions determine CH4 fluxes (Costa and Leigh 2010). The CH4 cycle is strongly affected by climate change, both by direct means (abiotic—temperature, humid condition of the soil) and indirectly through the change in vegetation (biotic—microbiome) because they are interconnected in regulating the cycle according to the requirement (Korrensalo et al. 2022) as depicted in Fig. 7. Anaerobic digestion of organic matter occurs via hydrolysis, acidification, acetogenesis, and methanogenesis (Seemann and Thunman 2019; Xu et al. 2021). Each process occurs balanced, thereby preventing the accumulation of metabolite intermediating in the system. Temperature and pH may affect the methanogenesis and the pathway of abundance in the biome community (Dhaked et al. 2010). Methanogenesis is an interconnected pathway with carbon–nitrogen cycles concerning their habitat biome (Park et al. 2018).

Fig. 7
figure 7

Diverse microbiome interaction among the oxic and anoxic communities to maintain the biogeochemical cycle (Gao and Lu 2021; Wang and Lee 2021; Korrensalo et al. 2022)

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Conclusion and future perspectives

The increasing population and development in developing countries have significantly impacted the environment, accumulating greenhouse gas (GHG) and causing global climate imbalance. The global bio-geo sector produces 1.2 Gt of CO2 annually, and the UN’s climate report, “Now or Never,” aims to limit global warming to 1.5 ℃ (Richard et al. 2021). The atmospheric CH4 load is rising, contradicting the 2015 Paris Agreement targets of the UN Framework Convention on Climate Change (Nisbet et al. 2020). It is also described in the latest report from IPCC as “a litany of broken climate promises,” revealing a “yawning gap between climate pledges and reality” (UN News report, Global perspective Human stories 2022) and also added that investing in climate-chocking industries. The G7 Leaders Declaration from May 2016 to “recognize the importance of mitigating emissions of short-lived climate pollutants” also supports a variety of existing strategies (Saunois et al. 2016).

According to IEA greenhouse gas emissions from energy, the industry was the largest sector for about 40% of global emissions in 2019 (International Energy Agency, Greenhouse Gas Emissions from Energy: Overview, 2021). For the past five decades, there has been a clear need in various sectors for a sustainable transition source of energy production. The world is at an alarming stage, fighting for future sustainability (Cain et al. 2021). As discussed above, many renewable, carbon–neutral sources are available, and in the past two decades, it has been proven and optimized. Enhanced technological development is needed in the sustainable bioenergy sector for future wellness. At the IEA March 2022 ministerial meeting press release, global energy leaders vow to accelerate and strengthen the clean energy transition. One of the main focuses of US and international climate policy is reducing CH4 emissions from oil and gas installations. Leak detection and repair programs (LDAR) that rely on surveys based on optical gas imaging (OGI) are regularly used to reduce fugitive emissions or leaks (Fox et al. 2019; Kemp and Ravikumar 2021). However, swift action to cut CH4 emissions from fossil fuel operations is the most effective strategy to minimize near-term climate change. The Paris Agreement (Birol 2023), which all 197 UNFCCC members signed or endorsed in 2018, intends to restrict global warming to 2 ℃ (Meinshausen et al. 2022; Birol 2023).

Microorganisms are abundant natural products that can be used for fuels and fine chemicals (Colin et al. 2011; Chubukov et al. 2016; Sindhu et al. 2019). A diverse substrate utilization potential in microbial strains could provide a competitive advantage in biofuel production. Anaerobic digestion can produce nearly half of the biogas’s CH4, which can be upgraded to over 90% CH4, which has the same uses as natural gas (Mitchell et al. 2015). However, the accessibility of technical resources to reduce CH4 emissions is unconscionable. The benefits of mitigating climate change extend beyond preventing global warming and fulfilling responsibilities and are crucial for a sustainable future.

Along with helping the environment, lowering CH4 emissions might increase agricultural yields and human health by concurrently reducing ozone generation and opening up new business and job prospects (Methane Possible 2023). Thus, governmental organizations must participate in implementing schemes under shifting to bioenergy sources and waste-to-energy conversion (Mboowa et al. 2017; Liang et al. 2022; Bajar et al. 2021), for a better future (International Energy Agency: Ministerial Meeting 2022).