Mapping the progress of soil biodiversity studies in India to address research gaps and opportunities

Soil biodiversity is a key indicator of soil health and soil fertility. Earlier studies focused on ecological and taxonomic aspects and documentation of soil faunal diversity across Indian agroecosystems. However, the soil-crop-biodiversity-regional nexus was limitedly explored. In the present study, we synthesised 41 studies published from 1970 to 2025 to identify the (a) research gap and opportunities, and (2) assess the relationship between agroecosystem and soil biota using the ROSES protocol. A total of 205 soil faunal species/orders, including microfauna (47), mesofauna (56), and macrofauna (102) respectively, from 11 agricultural and tree-based land uses practised in eight states and two union territories were recorded. A total of 20 soil faunal groups across six soil types or orders were recorded in Tripura and Tamil Nadu, while a weaker association between soil faunal diversity and soil type was observed in Leh and Ladakh, Meghalaya, and Rajasthan. Synthesis revealed that Inceptisols and sandy loam soils support the maximum diversity of ants, earthworms, and microarthropods, particularly Collembola and Cryptostigmata. Soil faunal diversity across the states ranged between 0.3 and 3.8, respectively, in Uttar Pradesh and Meghalaya. Croplands under conventional farming with high levels of inorganic fertiliser and pesticides support lower soil faunal diversity and abundance. Isolates and mesofauna were strongly correlated ( r = 0.98), while species were negatively correlated with both mesofauna ( r = -0.17) and isolates ( r = -0.28). The principal component analysis suggested that most agroecosystems share similar soil faunal communities, whereas mixed plantations and mango orchards harbour unique, divergent communities. The nexus among soil microbial geomics, soil micro-foodweb, soil type, and crop-soil-nutrient dynamics needs to be explored to understand the significance of soil biodiversity in maintaining soil health. The synthesis recommends that Indian soil biodiversity work should align with the goals of the Global Soil Biodiversity Atlas (GSBA) and the Global Soil Biodiversity Initiative (GSBI), considering soil biodiversity a primary component of nature-based solutions (NbS) for sustainable agriculture.