1. Arthropod diversity and abundance were found to be significantly greater under organic agricultural practices than under conventional methods.

Countries like China, India, Pakistan, Nepal, Bangladesh, and the Philippines are distinguished by their predominant rice‒wheat cropping systems. This system spans approximately 10.3 million hectares in India alone, forming the cornerstone of the nation’s food security (Khedwal et al., 2023). However, the sustainability of this system is increasingly questioned due to various environmental and agricultural challenges (Yadav et al., 2021). The question here is whether ecosystem services are maintained and supported by existing agricultural practices. Soil arthropods, one of the most significant elements of soil-living communities, are crucial for preserving the health and quality of soil as well as for providing ecosystem services (Gonçalves et al., 2021). They play a highly recognized role in various ecosystem service-related processes, including the breakdown and decomposition of organic matter, the cycling of nutrients, the creation of soil structure, and ultimately the management of soil water holding and availability (Parisi and Menta, 2008; Bengtsson et al., 2005). Furthermore, since they are incredibly suited to certain soil conditions and because they live, feed, and reproduce in the soil, some groups are especially sensitive to changes in the quality of the soil (Holland and Luff, 2000).

Additionally, wheat is particularly susceptible to heat waves, and rice as a highly water-demanding crop, contributes significantly to greenhouse gas emissions. Moreover, there is a declining response per fertilizer unit, compelling farmers to use increased quantities to achieve similar yields, leading to groundwater contamination with nitrates (Datta et al., 2022). This situation underscores the growing importance of organic (farmyard manure, vermicompost, and jivamrit) and regenerative practices (ecological engineering for pest control, zero-tillage, and on-site crop residue management) for ensuring long-term production sustainability.

Advocated for integrating a short-duration mungbean crop and incorporating its residues during summer to enhance system sustainability. Prasad and Misra (2001) also recommend applying farmyard manure (FYM) at 10 t ha^-1 alongside recommended NPK doses. These practices aim to maintain the viability of the rice-wheat cropping system.

Moreover, the success of the rice-wheat-mungbean production system is heavily influenced by effective weed management. Conservation agriculture, which has gained widespread adoption for its contributions to sustainability, plays a crucial role in this context. It is essential to recognize that altering faunal habitats, often through vegetation removal, significantly impacts arthropods, which are crucial for agroecosystem ecological functions (Quinn et al., 2016). Arthropods, which are sensitive to changes in vegetation, contribute to detritus degradation and organic matter cycling, thereby supplying nutrients to other organisms (Giesy et al., 2000; Roy et al., 2018). The mechanical alteration of soil, variations in plant residue quantity and placement, and changes in weed communities all affect arthropod communities (Ponce et al., 2011). Effects of tillage are important on soil arthropods frequency and intensity (Bhan and Behera, 2014). In direct planting systems, crop residues are concentrated at the surface, fostering a more intricate biological system and maintaining stable microclimatic conditions, particularly regarding soil humidity and temperature. This creates a more favorable habitat for soil fauna, and this was well reviewed by Chen et al. (2024).

Additionally, the diversity of natural enemies, including larger arthropods, plays a pivotal role in the biological control of arthropods (Menta and Remelli, 2020; Huot et al., 2018; Ponce et al., 2011). It has been found that agricultural expansion affects the species composition of communities, has a detrimental impact on the diversity of their functional traits, and thus attenuates the functioning of ecosystems and the benefits they provide (Emmerson et al., 2016). Contemporary agricultural practices such as conventional tillage, deep tillage, intensive and imbalanced use of chemical fertilizers, and widespread pesticide application have contributed to a decline in arthropod populations (Gonçalves et al., 2021). These practices result in complex interactions among natural enemies, leading to positive, negative, and neutral outcomes. A stable insect community emerging from these interactions forms an intricate food chain and web, providing significant opportunities for community interaction and compensation if one pathway is disturbed (Menta and Remelli, 2020; Huot et al., 2018).

Furthermore, Hong et al. (2022) demonstrated the connection between biodiversity and ecosystem health. The excessive use of fertilizers and pesticides, coupled with poorly coordinated development and landscape transformation in modern intensive agricultural practices, has led to pollution in water and soil environments and eradicated the biological refuge and habitat provided by wheat and rice fields (Hong et al., 2022). The biodiversity established in rice‒wheat fields is essential for stable ecosystems, contributing significantly to the ecosystem services offered by paddy fields and creating economic value for society.

Unfortunately, sufficient database on soil organisms (including arthropods) and their role in ecosystem functions are still lacking (Havlicek, 2012). Their significance in agriculture is presented only as worldwide statistics and in the form of straightforward facts suitable for mass audiences. The growing concern about sustainability in agriculture and the food industry, as well as the role of soil quality, may shed light on the significance of a thorough understanding of soil arthropod communities and the critical role they play in maintaining soil quality and health (Menta and Remelli, 2020). Thus, understanding soil arthropod communities under different soil nutrient management practices can aid in the development of management plans for sustainable agriculture. The hypothesis of the study is that different organically managed crop fields may help increase soil arthropod biodiversity for soil and agricultural sustainability. Thus, the study aimed to explore, evaluate, and compare the abundance, family diversity, and prey-predator composition of arthropods in rice-wheat cropping systems under conventional (chemical fertilizer- and pesticide-based agricultural practices), organically amended (use of compost and organic solutions), and regenerative (zero-tillage, crop residue management in the field, etc.) agricultural practices over three-year post-conversion from conventional practices. This study focused on a diverse group of arthropods with distinct functions, including insects such as spiders, ants, grasshoppers, earthworms, and beetle insects, and elucidated the importance of this existing cropping system.

The study, encompassing five scenarios and 13 arthropod families, explored the fauna within a three-year rice-wheat cropping system and revealed significant results of the management The present study aimed to assess the impacts of various long-term crop establishment, residue management and sustainable agricultural practices on arthropod diversity and composition under the subtropical humid climate of the Eastern Indo-Gangetic Plain of Uttar Pradesh, India. Soil flora–fauna diversity has been reported to be strongly affected by tillage in our findings and supported by literature (Moretti et al., 2017; Gora et al., 2022). As a significant number of arthropoda (13 arthropod families) were found in the study, it is to be noted that the number of soil-dwelling Diptera in temperate zones can reach higher, may be 50–150 species (Frouz, 1999; Ponce et al., 2011; Vera-Aviles et al., 2020). Depending on the family to which they belong—for example, Chironomidae in wet grasslands and Empididae in deciduous tree formations—they are more prevalent in forests than on arable land (Menta and Ramelli, 2020). Coleoptera, another arthropod reported in the study, is the largest order of beetles, and are frequently utilized as indicators because of their quick reaction to disturbances (forest cutting, grazing, fertilization, and habitat fragmentation). Additionally, they are also dependent on numerous biotic and abiotic variables that regulate their population as well (Rainio and Niemelä, 2003). However, the integration of organic farming is expected to result in a delayed positive response in species groups due to slow changes in soil properties and limitations in organism dispersal. Spiders, which are more abundant in the food web, may respond more slowly than other arthropods.

The decrease in Acarina abundance in Sc1, attributed to habitat modification rather than glyphosate use (van Eekeren et al., 2022; Giesy et al., 2000; George et al., 2017). Furthermore, the increased survival of specific mite groups in tilled soil could be due to their resilience to water scarcity, which is consistent with the findings of Moretti et al. (2017). This analysis describes and supports the complex interplay between population dynamics and environmental factors.

It is well known that organic amendments significantly enhance soil organic carbon and micronutrient levels, and thus influencing soil organisms (Crystal-Ornelas et al., 2021). In the compost-treated plots, it was found in our study that spiders exhibited larger abdomens, suggesting increased prey availability and reduced leaf damage. Despite no decrease in herbivore numbers, the larger spiders indicate potential shifts in predator‒prey dynamics. Spiders also played a significant role in neem-treated rice plots, as reported by Baitha et al. (2000a and 2000b). These findings highlight the complex relationships within the ecosystem and the positive impact of organic farming on plant resistance and pest control (Muneret et al., 2018) and meta-analyses by Crystal-Ornelas et al. (2021).

Furthermore, Formicidae are the most commonly utilized hymenopteran bio-indicator at the family level. Collembolan, mite, spider, and beetle species are richer than ant species and are more frequently used as environmental indicators. However, counting and identifying them takes longer than identifying ant species. They are also better indicators of assemblage composition than other groups and have a well-established ecology (Hoffmann and Anderson, 2003; Majer et al., 2007). Ants are well-known social insects that exhibit stationary nesting behavior. This characteristic of their ecology enables ant associations with the regions from which they are collected. Ants have been effectively employed as bio-indicators in Australia (Andersen and Majer, 2004), where their richness is connected with microbial activity in restored mining sites, as well as markers of pollution, the health of forests, and the state of rangelands. Since species assemblage, abundance, and richness are related to soil management factors, soil variables, and cropping practices, ants may have potential as biological indicators of soil conditions and management in agroecosystems. Previous research has indicated that ants respond to land changes in predictable ways. Additionally, because they may improve soil drainage, aeration, and nutrient supply, ants are crucial ecosystem engineers who help to implement low-impact farming practices. As indicated in Table 3, the Formicidae (ant) family boasts the greatest number of members, followed by the Araneae (spider) family. Table 3 shows the delayed or gradual responses of arthropods, potentially attributed to factors such as dispersal extent (referred to as “colonization credit”), residual effects of pesticides, the presence of chemical fertilizers in the soil, and the lag time associated with organic matter mineralization. Within the scope of the current study, specific taxa, including cockroaches, spiders, ants, and grasshoppers, gradually increased after the shift to organic farming. Among the factors mentioned above, dispersion limitation may not be the primary reason for the gradual increase, particularly in units adopting organic farming, such as the individual Sc2, Sc3, and Sc4 scenarios. Consequently, rapid immigration from neighboring habitats to these areas is anticipated. However, dispersal limitation could account for the observed changes in spiders and ants. These particular spiders are recognized for congregating in regions abundant in prey populations, yet their modus operandi revolve around daily site changes.

The study also highlighted the enhanced predator populations in zero-till wheat fields compared to conventionally sown fields (PCA analysis), suggesting that predator conservation could be a viable strategy for insect pest management in rice-wheat systems. The comprehensive PCA sheds light on the dynamic interplay of arthropod families in different agricultural contexts and underscores the potential of specific farming practices in promoting ecological balance.

A diverse ecosystem provides vital environmental buffers, offering necessary hosts, food, shelter, and overwintering sites, thereby reducing the likelihood of pest outbreaks and contributing to agricultural sustainability (Salim et al., 2003; Emmerson et al., 2016). This relationship, as provided in our study sites, between biodiversity and agricultural health highlights the need for integrated pest management strategies prioritizing ecological balance and sustainability. Additionally, this study provides vital insights into the time-dependent responses of organisms in rice‒wheat fields, highlighting the benefits of organic farming in supporting arthropod diversity. This diversity is crucial and is influenced by the scale and context of the agricultural system. The findings suggest that the arthropod population observed is sufficient for the needs of the organic farming community, emphasizing the overall benefits of organic practices in agricultural ecosystems.

The results of this study revealed a significant increase in arthropod populations in rice-wheat cultivation under organic farming practices (Sc2 and Sc3) as compared to conventional methods. The use of organic fertilizers and the integration of legume (mungbean) crops in this study showed a critical factor in enhancing the abundance and diversity of arthropods in organic (Sc2) and no-till (ZT) systems. A notable increase in arthropod populations as well predator-prey population was observed in Scenario 2, where implementing cover crops such as mulch played a critical role (no-tillage). Macrofauna and mesofauna were higher in Sc4 supporting the climate based ecological farming. This research underscores the complex relationship between agricultural practices and arthropod dynamics, emphasizing the ecological advantages of adopting organic and sustainable farming approaches for enhancing biodiversity and contributing to a more sustainable ecosystem.