Beneath the Surface: Comparative Diversity, Abundance, and Bio-Indicative Capabilities of Nematode Community Structure in Natural and Disturbed Habitats

Abstract

This present study underscores the significance of soil nematodes as indicators of ecological health, particularly in areas affected by human activities like mining. Soil nematodes, classified into five trophic groups, play vital roles in nutrient cycling and provide insights into soil food web dynamics. Various nematode community indices, including the maturity index (MI) and trophic diversity index (TDI), are crucial for assessing soil food web diversity. Nematodes exhibit adaptability across diverse soil environments, from pristine to highly disturbed habitats, making them responsive indicators of environmental changes. Understanding nematode community structure enhances their potential as global indicators for assessing food resource availability and habitat characterization. This study compares three different zones based on anthropogenic disturbances in the coal mining region of Sonebhadra, Uttar Pradesh, representing undisturbed, moderately disturbed, and intensely disturbed sites. By analyzing nematode communities and trophic group abundance, the study assesses soil ecosystems across these zones. Human activities, especially mining, significantly impact soil nematode diversity and ecosystem health. Transition from natural forests to mining sites leads to shifts in nematode communities and species diversity, with intermediate disturbance fostering increased species diversity. Maturity index values reflect ecosystem maturity, with undisturbed and moderately disturbed zones indicating structured ecosystems, while highly disturbed zones represent degraded conditions. Faunal profiles mirror these findings, indicating shifts in decomposition pathways. This study highlights the potential of nematodes as indicators for environmental monitoring and quality assessment in coal mine areas. Further research on individual nematode species can inform biodiversity modeling and contribute to more effective ecological restoration efforts.

1. Introduction

Nematodes have been categorized into five primary trophic groups [1, 2]. They play a significant role in nutrient mineralization through energy decomposition pathways [3, 4, 5, 6] and offer valuable insights into the structure and function of soil food webs [1, 7, 8, 9]. Nematode community indices, such as the maturity index (MI) based on c-p scaling, the plant parasitic index (PPI) (weighted mean of c-p values of plant-parasitic nematodes), species richness, evenness, the ratio of bacterivore to fungivore nematodes, and the trophic diversity index (TDI), are routinely employed to assess soil food web diversity conditions [10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20]. Furthermore, various faunal food web indices for nematodes, such as enrichment (EI), structure (SI), and decomposition channel index (CI), based on the relative weighted abundance of nematode c-p guilds, provide information on enrichment, trophic connections, structure, and prevailing decomposition in a food web [1].

Nematodes are valuable indicators as they inhabit soils ranging from pristine to highly disturbed habitats and are represented in almost all trophic groups of the soil food web. They respond quickly and specifically to environmental changes. A comprehensive understanding of nematode community structure for assessing food resource availability and characterizing different habitats would enhance the indicative capability of nematodes on a global scale [1, 21].

Although we have limited knowledge about the influence of vegetation and abiotic parameters on nematode fauna, drawing trends can be challenging due to geological, climatological, and methodological differences among various sites or studies [22]. Analyzing the soil nematode community can reveal differences between habitats [19, 21].

In the present study, three different zones with varying degrees of anthropogenic disturbances in the coal mine region of district Sonebhadra, Uttar Pradesh, were compared. Various parameters of the nematode community were used to assess the prevailing soil ecosystem in these zones. Depending on the nature and frequency of disturbances (physical, chemical, or biological), active mining land and wild forests (potential future mining sites) represent two extremes in terms of ecosystem structure and stability. The three zones identified based on the degree of human interference were: undisturbed hillocks or potential future mining sites (Zone ‘A’), moderately disturbed and managed habitat represented by abandoned reclaimed land after mining (Zone ‘B’), and intensively disturbed habitat as the active mining site (Zone ‘C’).

The objectives of the study were to compare these three selected habitats using a combination of nematode community indices and trophic group abundance and to examine substrate characteristics through nematode community measures using multivariate analyses.

2. Description of site and protocol of study

See Figure 1.

Figure 1.

A. Satellite images of the coal mine region. B. Topographic map of the study region showing three different zones. Zone ‘A’ = green color, Zone ‘B’ = light green color (samples were collected from median age coalmine spoils from this zone), Zone ‘C’ = dark blue color.

The coal mine region was divided broadly into three differentiating sites on gradient of anthropogenic disturbances.

Zone ‘A’: This area represented the unmined hills covered with wild vegetation and with least or no anthropogenic activities. Samples were collected on altitudinal gradients from foothill to top. The Zone lies between the geographic coordinates 24° 11′57.73″N, 82° 44′31.95″E to 24° 08′49.06″N, 82° 43′33.85″E (Figure 2A and B).

Figure 2.

A, B: Snapshots of Zone ‘A’.

Zone ‘B’: The area represented reclaimed overburden of about 21 years of age. For the proper management of spoils, anthropogenic inference occurs time to time. Samples were collected on an altitudinal gradient from foot to top of overburden. This Zone lies between the geographic coordinates 24° 10′32.99″N, 82° 45′51.29″E to 24° 07′40.38″N, 82° 48′32.51″E (Figure 3A and B).

Figure 3.

A, B: Snapshots of Zone ‘B’.

Zone ‘C’: The area represented the highly disturbed zone with an extremely nutrient-poor environment. Samples were collected on both altitudinal and horizontal basis. The samples were collected between the geographic coordinates 24° 10′57.92″N, 82° 45′07.83″E to 24° 07′47.38″N, 82° 43′24.89″E (Figure 4A and B). On horizontal basis, the active coal mining region was considered as source of disturbance, and the samples were collected in a circumference of 400 m diameter.

Figure 4.

A, B: Snapshots of Zone ‘C’.

3. Materials and methods

Sampling for Zone ‘A’: Soil sampling was done on an altitudinal gradient from the foot to the top on undisturbed hills. Samples were taken 15–25 cm below the ground level.

Sampling for Zone ‘B’: Soil sampling was done from top to bottom and from the bench of the coal mine spoil.

Sampling for Zone ‘C’: Samples were taken at a 15 m distance along the altitudinal gradient starting from ground level (about 160 m above sea level) to the top (about 400 m high).

Sampling was done using steel corer of 5 cm diam. For each Zone 30 samples were collected with each sample being a composite of five samples. Samples were then stored in plastic bags and transported to the lab for chemical analysis and nematode identification. The climatic and edaphic information were also recorded (Table 1). Geographic data like geographic coordinates, altitude, and temperature were recorded via the navigation device GARMIN -eTREX- 20.

Nematode species	Functional guild	Mean ± SD (abundance)
Bacterivores		Zone ‘A’; Undisturbed forest; (site for advance quarry)	Zone ‘B’; Spoil of median age	Zone ‘C’; Active site of mining
Achromadora indica	Ba2	10.56 ± 3.54	28.24 ± 21.24	0.0 ± 0.0
Acrobeles cylindricus	Ba2	14.39 ± 16.54	20.12 ± 15.54	0.0 ± 0.0
Acrobeloides conoidis	Ba2	10.34 ± 7.45	12.45 ± 8.64	0.48 ± 0.75
Acrobeloides nanus	Ba2	18.15 ± 2.56	15.10 ± 12.10	0.0 ± 0.0
Acrobelophis minimus	Ba2	5.24 ± 3.21	0.63 ± 2.25	0.0 ± 0.0
Alaimus primitivus	Ba3	18.35 ± 32.30	30.34 ± 44.53	0.0 ± 0.0
Amphidelus sylvaticus	Ba3	16.3 ± 15.53	13.54 ± 8.64	0.0 ± 0.0
Cephalobus cubaensis	Ba2	10.4 ± 6.24	7.52 ± 10.25	0.0 ± 0.0
Cephalobus parvus	Ba2	10.86 ± 7.25	7.81 ± 5.23	0.0 ± 0.0
Ceratoplectus armatus	Ba2	9.26 ± 4.23	19.83 ± 25.3	0.0 ± 0.0
Chiloplacus symmetricus	Ba2	1.45 ± 7.59	0.25 ± 1.25	0.0 ± 0.0
Chiloplectus indicus	Ba2	0.50 ± 2.76	0.65 ± 2.54	0.0 ± 0.0
Eucephalobus oxyuroides	Ba2	16.68 ± 18.85	18.25 ± 12.24	0.0 ± 0.0
Geomonhystera glandulata	Ba2	12.24 ± 8.35	8.53 ± 12.53	0.0 ± 0.0
Halicephalobus gingivalis	Ba1	0.00 ± 0.00	0.94 ± 3.65	0.0 ± 0.0
Mesorhabditis vernalis	Ba1	13.51 ± 8.56	22.45 ± 9.45	0.36 ± 0.67
Mesorhabditis minuta	Ba1	8.45 ± 6.45	15.53 ± 12.67	0.48 ± 0.84
Monhystera gracilis	Ba2	11.84 ± 6.85	15.28 ± 14.53	0.0 ± 0.0
Monhystrella kerryi	Ba2	12.54 ± 6.44	9.28 ± 5.68	0.0 ± 0.0
Oscheius vulvastriatus sp .n.	Ba1	0.00 ± 0.00	8.22 ± 3.25	0.0 ± 0.0
Panagrellus dubius	Ba1	3.15 ± 1.23	1.75 ± 0.57	0.0 ± 0.0
Panagrolaimus dendroctoni	Ba2	15.83 ± 6.86	8.75 ± 6.55	0.0 ± 0.0
Plectus geophilus	Ba2	16.84 ± 18.24	18.49 ± 20.24	0.0 ± 0.0
Plectus parvus	Ba2	7.42 ± 4.24	5.77 ± 14.99	0.0 ± 0.0
Poikilolaimus oxycercus	Ba1	2.15 ± 0.24	0.55 ± 2.50	0.0 ± 0.0
Prismatolaimus intermedius	Ba3	12.46 ± 14.48	16.86 ± 12.86	0.0 ± 0.0
Teratolobus regulus	Ba3	2.43 ± 1.75	1.25 ± 3.45	0.0 ± 0.0
Tylocephalus primitivus	Ba2	3.26 ± 2.36	3.86 ± 1.67	0.0 ± 0.0
Wilsonema bangaloreiensis	Ba2	3.35 ± 1.75	3.55 ± 5.43	0.0 ± 0.0
Zeldia punctata	Ba2	2.72 ± 2.24	0.74 ± 2.24	0.0 ± 0.0

Table 1.

Abundance of bacterivore species in three zones of coal mine region of district Sonebhadra Uttar Pradesh.

4. Results and observations

4.1 Nematode abundance

Zone ‘A’: Nematode abundance was found high in Zone ‘A’ and mean value of 1748.63 ± 163.18 (1576–1859) nematodes were found in 100 g of samples.

Zone ‘B’: Nematode abundance was low in Zone ‘B’ comparably to Zone ‘A’ and mean value of 983.8 ± 120.2 (748.57–1168.74) nematodes were found in 100 g of samples.

Zone ‘C’: Nematode abundance was negligible in Zone ‘C’, which was the active mining Zone and mean of 0.42 ± 0.37 (0.08–0.42) nematodes isolated from 100 g of samples.

4.2 Nematode species diversity

Zone ‘A’: A total of 119 species belonging to 107 genera, 40 families and eight orders were recorded from Zone ‘A’. The dominant species were Aphelenchoides composticola, Aphelenchus avenae, Dorylaimoides constrictus, Labronema baqrii, Labronema deoriaensis, Laimydorus baldus, Thornenema mauritianum, Tripyla glomerans, Tripyla arenicola, Mylonchulus contractus, Mylonchulus vasis, Sporonchulus ibitiensis, Aporcelaimellus tropicus.

Zone ‘B’: Zone ‘B’ recorded 105 species belonging to 96 genera, 39 families and eight orders. The number and dominance were quite comparable with Zone ‘A’.

Zone ‘C’: Only three species belonging to two genera, one family and one order were observed at Zone ‘C’ (Figure 5).

Figure 5.

Number of species, genera and individuals observed in three different zones of coal mine region.

4.3 Nematode trophic structure

In Zone ‘A’ there was much diversity of omnivores and predators in comparison to bacterivores and in Zone ‘B’ bacterivores and fungivores nematodes were the abundant group over omnivores and predators and Zone ‘C’ had only three bacterivore species.

4.3.1 Zone ‘A’

4.3.1.1 Trophic groups

Bacterivores (bacteriophagous): Of the 28 bacterivore species recorded (Table 2), five most abundant species were Acrobeloides nanus, Plectus geophilus, Eucephalobus oxyuroides, Amphidelus sylvaticus and Acrobeles cylindricus.

Nematode species	Functional guild	Mean ± SD (abundance)
Fungivores		Zone ‘A’; Undisturbed forest (Site for advance quarry)	Zone ‘B’; Spoil of Median Age	Zone ‘C’; Active site of mining
Aglenchus agricola	Fu2	16.43 ± 6.05	16.48 ± 8.45	0.0 ± 0.0
Aphelenchus avenae	Fu2	32.04 ± 18.64	12.6 ± 10.35	0.0 ± 0.0
Aphelenhoides besseyi	Fu2	36.13 ± 20.13	18.74 ± 16.36	0.0 ± 0.0
Axonchium thoubalicum	Fu5	9.40 ± 3.56	2.25 ± 1.75	0.0 ± 0.0
Basiriotyleptus minimus	Fu2	8.95 ± 4.31	6.25 ± 4.21	0.0 ± 0.0
Belondira apitica	Fu5	10.42 ± 4.10	5.40 ± 2.50	0.0 ± 0.0
Daladenus wilsoni	Fu2	3.67 ± 1.58	13.43 ± 6.48	0.0 ± 0.0
Diptherophora alami	Fu3	12.10 ± 4.20	4.61 ± 2.80	0.0 ± 0.0
Ditylenchus dipsaci	Fu2	3.26 ± 2.05	11.4 ± 6.23	0.0 ± 0.0
Dorylaimellus indicus	Fu5	16.82 ± 6.42	8.64 ± 3.56	0.0 ± 0.0
Dorylaimoides constrictus	Fu2	39.27 ± 20.46	13.45 ± 6.45	0.0 ± 0.0
Filenchus mircodorus	Fu2	22.30 ± 10.46	16.43 ± 8.23	0.0 ± 0.0
Filenchus vulgaris	Fu2	18.20 ± 9.65	15.43 ± 6.28	0.0 ± 0.0
Leptonchus granulosus	Fu2	4.85 ± 2.24	5.44 ± 3.24	0.0 ± 0.0
Roqueus indicus	Fu5	4.64 ± 3.41	5.53 ± 2.54	0.0 ± 0.0
Tylencholaimellus acutus	Fu4	28.41 ± 14.42	12.34 ± 6.80	0.0 ± 0.0
Tyleptus projectus	Fu2	7.23 ± 3.54	10.23 ± 4.25	0.0 ± 0.0

Table 2.

Abundance of fungivores species in three zones of coal mine region of district Sonebhadra Uttar Pradesh.

Fungivores (mycophagous): Seventeen fungivore species were recorded (Table 3), among which the five most abundant ones were Dorylaimoides constrictus, Aphelenhoides composticola, Aphelenchus avenae, Tylencholaimellus acutus and Filenchus mircodorus.

Nematode species	Functional guild	Mean ± SD (abundance)
Herbivores		Zone ‘A’; Undisturbed forest (site for advance quarry)	Zone ‘B’; Spoil of median age	Zone ‘C’; Active site of mining
Basiria abberans	H2	16.80 ± 6.46	7.25 ± 4.23	0.0 ± 0.0
Boleodorus filiformis	H2	9.35 ± 4.05	3.36 ± 2.35	0.0 ± 0.0
Coslenchus areolatus	H2	6.87 ± 5.64	1.53 ± 2.50	0.0 ± 0.0
Helicotylenchus dihystera	H3	9.64 ± 4.38	12.68 ± 5.85	0.0 ± 0.0
Hemicriconemoides communis	H3	15.38 ± 8.36	6.86 ± 4.25	0.0 ± 0.0
Hemicycliophora corbetti	H3	1.50 ± 2.35	1.02 ± 2.21	0.0 ± 0.0
Hoplolaimus indicus	H3	2.30 ± 3.66	10.25 ± 6.23	0.0 ± 0.0
Longidoroides longiurus	H5	13.45 ± 8.36	2.52 ± 0.0	0.0 ± 0.0
Longidorus elongatus	H5	16.84 ± 10.35	1.08 ± 2.50	0.0 ± 0.0
Malenchus nanellus	H2	4.68 ± 3.45	1.24 ± 3.65	0.0 ± 0.0
Merlinius brevidens	H3	3.87 ± 2.36	1.25 ± 0.58	0.0 ± 0.0
Neopsilenchus affinis	H2	2.48 ± 2.01	1.20 ± 2.36	0.0 ± 0.0
Paratylenchus similis	H2	9.85 ± 6.46	12.26 ± 6.58	0.0 ± 0.0
Pratylenchus brachyurus	H2	10.64 ± 6.68	0.0 ± 0.0	0.0 ± 0.0
Psilenchus mixus	H3	4.65 ± 3.34	0.56 ± 1.14	0.0 ± 0.0
Rotylenchus mircrostylus	H3	6.80 ± 4.88	0.26 ± 2.24	0.0 ± 0.0
Scutellonema brachyurum	H3	1.54 ± 2.34	0.50 ± 1.54	0.0 ± 0.0
Scutylenchus hexincisus	H3	2.38 ± 1.36	0.35 ± 2.25	0.0 ± 0.0
Trichodorus borai	H4	8.62 ± 4.38	1.24 ± 2.52	0.0 ± 0.0
Tylenchorynchus striatus	H3	11.56 ± 8.44	10.23 ± 6.45	0.0 ± 0.0
Tylenchus arcuatus	H3	12.56 ± 6.35	5.86 ± 3.54	0.0 ± 0.0
Xiphinema americanum	H5	6.24 ± 9.25	9.25 ± 5.24	0.0 ± 0.0

Table 3.

Abundance of herbivore species in three zones of coal mine region of district Sonebhadra Uttar Pradesh.

Herbivores (plant parasites): Of the 22 herbivore species (Table 4), five most abundant ones were Longidorus elongates, Basiria abberans, Longidoroides longiurus, Tylenchus arcuatus and Tylenchorynchus striatus.

Nematode species	Functional guild	Mean ± SD (abundance)
Omnivores		Zone ‘A’; Undisturbed forest (site for advance quarry)	Zone ‘B’; Spoil of median age	Zone ‘C’; Active site of mining
Amphidorylaimus flagellicauda	Om4	6.24 ± 4.36	—	—
Cephalodorylaimus papillatus	Om4	6.20 ± 5.48	—	—
Crassolaibium gharwaliense	Om4	16.84 ± 9.65	4.24 ± 2.35	—
Discomyctus cephalatus	Om4	12.86 ± 9.80	6.33 ± 3.26	—
Dorylaimus stagnalis	Om4	10.54 ± 5.46	1.56 ± 3.28	—
Enchodelus macrodorus	Om4	8.64 ± 5.24	0.45 ± 1.56	—
Eudorylaimus silvaticus	Om4	13.64 ± 8.30	5.26 ± 3.25	—
Eumenicus monhystera	Om4	8.64 ± 5.45	—	—
Ischiyodorylaimus navus	Om4	3.58 ± 4.24	—	—
Labronema deoriaensis	Om4	20.42 ± 12.92	15.50 ± 11.54	—
Labronema baqrii	Om4	24.56 ± 18.45	18.35 ± 8.62	—
Allodorylaimus irritans	Om4	31.54 ± 22.56	2.45 ± 3.56	—
Makatinus heynsi	Om4	7.45 ± 6.52	—	—
Mesodorylaimus subtiloides	Om4	20.38 ± 11.36	—	—
Mesodorylaimus indicus	Om4	20.38 ± 16.36	23.56 ± 13.46	—
Microdorylaimus parvus	Om4	18.45 ± 8.46	8.54 ± 5.64	—
Moshajia idiofora	Om4	12.45 ± 6.75	8.65 ± 5.60	—
Opisthodorylaimus cavalcantii	Om4	16.45 ± 9.45	—	—
Oriverutus sundarus	Om4	19.44 ± 12.46	—	—
Oxydirus ganagticus	Om5	10.65 ± 6.54	—	—
Paraoxydirus gigas	Om5	8.64 ± 4.84	—	—
Porodorylaimus sturhani	Om4	15.46 ± 12.24	—	—
Pungentella porosa	Om4	9.86 ± 5.68	—	—
Pungentus angulatus	Om4	12.6 ± 9.83	2.60 ± 1.35	—
Thonus cylindricus	Om4	14.24 ± 8.38	13.50 ± 8.45	—
Thornenema mauritianum	Om4	22.54 ± 16.38	15.68 ± 8.54	—

Table 4.

Abundance of omnivores species in three zones of coal mine region of district Sonebhadra Uttar Pradesh.

Omnivores: Five most abundant species among the 25 omnivore species (Table 5) were Allodorylaimus irritans, Thornenema mauritianum, Labronema deoriaensis, Mesodorylaimus indicus and Mesodorylaimus subtiloides.

Nematode species	Functional guild	Mean ± SD (abundance)
Predators		Zone ‘A’; Undisturbed forest (site for advance quarry)	Zone ‘B’; Spoil of median age	Zone ‘C’; Active site of mining
Actinolaimus armatus	Ca5	12.22 ± 5.64	4.68 ± 2.52	—
Actus minutus	Ca4	11.22 ± 6.42	6.86 ± 6.36	—
Aporcelaimellus tropicus	Ca4	22.60 ± 14.38	15.50 ± 8.46	—
Aporcelaimellus heynsi	Ca4	12.68 ± 8.42	—	—
Aquatides minutus	Ca5	4.23 ± 6.69	9.40 ± 6.53	—
Clarkus sheri	Ca4	9.68 ± 4.38	—	—
Discolaimodes bulbiferus	Ca5	16.46 ± 10.26	14.84 ± 5.21	—
Discolaimus major	Ca5	12.45 ± 8.62	15.60 ± 8.64	—
Iotonchus monhystera	Ca4	10.12 ± 5.36	6.18 ± 2.48	—
Iotonchus indicus	Ca4	15.99 ± 8.59	4.21 ± 3.26	—
Ironus dentifurcatus	Ca4	18.62 ± 9.96	8.64 ± 4.42	—
Laimydorus papillatus	Ca4	16.45 ± 4.66	—	—
Laimydorus baldus	Ca4	22.68 ± 6.68	15.21 ± 8.62	—
Michonchus rectangularis	Ca4	14.44 ± 8.64	11.64 ± 6.30	—
Mononchoides longicauda	Ca1	—	0.25 ± 3.36	—
Mulveyellus jairi	Ca4	9.66 ± 3.36	1.89 ± 2.06	—
Mylonchulus contractus	Ca4	23.45 ± 14.64	15.24 ± 11.42	—
Mylonchulus viasis	Ca4	26.20 ± 18.46	16.54 ± 8.44	—
Neoactinolaimus thornei	Ca5	6.48 ± 5.36	3.05 ± 2.58	—
Nygellus subclavatus	Ca4	16.28 ± 6.66	6.26 ± 5.88	—
Nygolaimus timmi	Ca5	8.35 ± 6.45	2.83 ± 1.26	—
Prionchulus muscorum	Ca4	8.32 ± 4.32	—	—
Solidedens bisexualis	Ca5	6.64 ± 7.38	4.21 ± 2.36	—
Sporonchulus ibitiensis	Ca4	25.68 ± 44.61	10.58 ± 13.60	—
Sporonchulus vagabundus	Ca4	18.68 ± 12.68	5.36 ± 3.36	—
Tripyla glomerans	Ca3	24.35 ± 18.38	32.26 ± 22.42	—
Tripyla arenicola	Ca3	31.24 ± 24.24	20.25 ± 12.24	—

Table 5.

Abundance of predator species in three zones of coal mine region of district Sonebhadra Uttar Pradesh.

Predators: Of a total of 26 predator species (Table 6), the five most abundant ones were recorded as Tripyla arenicola Mylonchulus viasis Tripyla glomerans Mylonchulus contractus and Laimydorus baldus.

	Type Area ‘A’; Non minning forest	Type Area ‘B’; Spoil of median age	Type Area ‘C’; Active site of mining
Genera (total count)	109	104	2
Species (total count)	114	110	3
Individuals	1748.63 ± 163.18 (1576–1859)	983.80 ± 120.24 (748.57–1168.74)	0.42 ± 0.37 (0.08–0.42)
Margalef diversity	16.17 ± 0.35 (15.58–16.79)	15.11 ± 0.59 (14.23–16.23)	—
Menhinick diversity	3.92 ± 0.35 (3.63–3.95)	3.43 ± 0.43 (2.85–3.98)	—
Simpson dominance	0.01 ± 0.00 (0.01–0.01)	0.01 ± 0.00 (0.01–0.01)	—
Inverse Simpson dominance	91.14 ± 3.25 (82.25–96.35)	67.50 ± 7.33 (54.32–76.15)	—
Hill’s effective index	98.23 ± 2.43 (97.24–99.89)	75.64 ± 4.90 (65.18–77.89)	—
Shannon diversity	4.58 ± 0.45 (3.97–5.65)	4.32 ± 0.44 (3.54–4.88)	—
Simpson diversity	0.99 ± 0.00 (0.99–0.99)	0.99 ± 0.00 (0.99–0.99)	—
Brillouin diversity	4.51 ± 0.65 (3.85–5.78)	4.19 ± 0.34 (3.50–4.60)	—
Sheldon Index	0.82 ± 0.00 (0.82–0.82)	0.72 ± 0.00 (0.72–0.72)	—
Heip Index	0.82 ± 0.00 (0.82–0.82)	0.72 ± 0.00 (0.72–0.72)	—
Maturity Index (MI)	3.46 ± 0.26 (3.36–3.87)	2.96 ± 0.50 (2.87–3.12)	—
Plant Parasitic Index (PPI)	0.78 ± 0.09 (0.50–1.25)	3.26 ± 0.23 (2.00–3.65)	—
Trophic Diversity Index (TDI)	1.17 ± 0.02 (1.06–1.32)	1.09 ± 0.04 (1.04–1.25)	1.00 ± 0.00 (1.04–1.25)
Nematode channel ratio (NCR %)	0.40 ± 0.02 (0.35–0.72)	0.68 ± 0.02 (0.62–0.73)	—
Structure Index (SI)	68.23 ± 10.20 (58.30–77.43)	45.1 5 ± 5.85 (40.68–52.68)	—
Enrichment Index (EI)	12.62 ± 4.66 (7.65–32.25)	22.62 ± 12.58 (16.53–64.65)	9.54 ± 1.54 (9.50–10.56)
Basal Index (BI)	41.28 ± 12.30 (32.04–62.05)	57.29 ± 8.10 (44.24–67.35)	74.46 ± 3.25 (70.13–78.16)
Channel Index (CI)	0.31 ± 0.40 (0.25–0.84)	0.54 ± 0.42 (0.50–1.24)	—

Table 6.

Ecological parameters of nematode population in three zones of coal mine region of district Sonebhadra Uttar Pradesh.

4.3.2 Zone ‘B’

4.3.2.1 Trophic groups

Bacterivores (bacteriophagous): Of the 29 bacterivore species recorded (Table 2), five most abundant species were Alaimus primitivus, Achromadora indica, Mesorhabditis vernalis, Acrobeles cylindricus and Ceratoplectus armatus.

Fungivores (mycophagous): Seventeen fungivore species were recorded (Table 3), among which five most abundant ones were Aphelenhoides composticola, Aglenchus agricola, Filenchus mircodorus, Dorylaimoides constrictus and Aphelenchus avenae.

Herbivores (plant parasites): Of the 21 herbivore species (Table 4), five most abundant ones were Helicotylenchus dihystera, Paratylenchus similis, Hoplolaimus indicus, Tylenchorynchus striatus and Xiphinema americanum.

Omnivores: The five most abundant species among the 15 omnivore species (Table 5) were Mesodorylaimus indicus, Labronema baqrii, Thornenema mauritianum, Labronema deoriaensis and Thonus cylindricus.

Predators: Of a total of 22 predator species (Table 6), the five most abundant ones were recorded as Tripyla glomerans, Tripyla arenicola, Mylonchulus vasis, Discolaimus major and Aprocelaimellus tropicus.

4.3.3 Zone ‘C’

4.3.3.1 Trophic group

Bacterivores: In Zone ‘C’ only three species were reported from bacteriovores (Table 2) viz., Mesorhabditis vernalis, Mesorhabditis minuta and Acrobeloides nanus.

4.4 Biomass

The relative biomass of different trophic groups (Figure 6) varied in three zones and are as follows:

Figure 6.

Percentage biomass of the different trophic groups in the three different zones of coalfield region.

Zone ‘A’: The highest biomass was of predators, that is, about 36% of the total nematode biomass and the lowest,that is, 8% was constituted by bacterivores. Omnivore species showed 32% biomass followed by herbivores (13%) while fungivores constituted 11% of the total nematode biomass. The total nematode biomass in this Zone was calculated to be 6162.99 μg in 100 g. of soil.

Zone ‘B’: The nematode biomass demonstrated similar trends in Zone ‘B’ compared to Zone ‘A’. The highest biomass was of predators that is, 37% of the total nematode biomass while herbivores constituted the lowest 13%, omnivores constituted 21% followed by bacterivores (15%) and fungivores (14%) of the total nematode biomass. The total nematode biomass in this Zone was estimated to be 3438.93 μg in 100 g of soil.

Zone ‘C’: In Zone ‘C’ there were only three bacterivore species that constitute nematode biomass. The total nematode biomass in this Zone was estimated to be 2.37 μg in 100 g of soil.

5. Diversity indices

Diversity indices and nematode maturity indices were calculated for each zone to assess the diversity of nematode species and maturity of soil ecosystem.

5.1 Margalef index (species richness)

In Zone ‘A’ the Margalef species richness index was found to be 16.17 ± 0.35 (15.58–16.79). Zone ‘B’ was calculated to be 15.11 ± 0.59 (14.23–16.23) and in Zone ‘C’, where only two species were recorded, the index was incalculable (Table 7 and Figure 7).

Characteristics	Mining sites
	Zone ‘A’; Undisturbed forest (site for advance quarry)	Zone ‘B’; Spoil of median age	Zone ‘C’; Active site of mining
<2.0 mm (gravel)	9.00 ± 0.92	13.00 ± 1.80	20.00 ± 2.15
2.–0.2 mm (sand)	63.00 ± 3.50	72.00 ± 5.24	88.55 ± 6.54
0.2–0.1 mm (silt)	13.00 ± 1.23	10.00 ± 0.24	3.00 ± 1.26
<0.1 mm (clay)	8.10 ± 1.45	7.80 ± 1.25	3.20 ± 1.56
pH	6.54 ± 0.02	6.82 ± 0.02	5.45 ± 0.26
Bulk density	1.25 ± 0.18	1.26 ± 0.08	1.75 ± 0.16
Natural moisture content (%)	12.20 ± 2.26	11.60 ± 0.28	6.2 ± 0.25
Porosity	46.27 ± 2.25	42.62 ± 2.65	33.65 ± 2.66
Water holding capacity	53.00 ± 0.92	52.00 ± 2.65	24.84 ± 3.25
Soil organic carbon (mg C/g)	3.45 ± 0.024	2.38 ± 0.028	ND
Total soil N (μg N/g)	2456.63 ± 148.34	194.94 ± 25.46	ND
Exchangeable K μg P/g spoil	271.95 ± 6.74	16.96 ± 2.35	ND
Electrical conductivity ms/cm	0.05 ± .01	0.33 ± 0.01	0.65 ± 0.01

Table 7.

Abiotic parameters in three zones of coal mine region of district Sonebhadra Uttar Pradesh.

Figure 7.

Comparison of species diversity indices in three selected zones.

5.2 Menhinick index (species richness)

Menhinick diversity, a measure to compare the species richness, was calculated to be 3.92 ± 0.35 (3.63–3.95) in Zone ‘A’, in Zone ‘B’ it was found to be 3.43 ± 0.43 (2.85–3.98) and the Menhinick index was incalculable for Zone ‘C’ (Table 7 and Figure 7).

6. Evenness indices

The values for both the evenness indices (Sheldon and Heip indices) were observed to be the same for the two Zones ‘A’ and ‘B’ and calculated to be 0.82 ± 0.00 (0.82–0.82) and 0.72 ± 0.00 (0.72–0.72), respectively. For Zone ‘C’ the values were inestimable (Table 7).

7. Maturity index

In Zone ‘A’ where there was the least disturbance, the MI was highest and a mean value of 3.46 ± 0.26 (3.36–3.87) was observed representing the structured soil ecosystem. Zone ‘B’ which represented coal mine-managed spoil of 21 years period, showed an MI equal to 2.96 ± 0.50 (2.87–3.12) while in Zone ‘C’ MI was incalculable (Table 7 and Figure 7).

8. Plant parasitic index (PPI)

In Zone ‘A’ the PPI was calculated to be 0.78 ± 0.09 (0.50–1.25) whereas in Zone ‘B’ the PPI value was 3.26 ± 0.23 (2.00–3.65). The PPI and MI showed an inverse correlation (Table 7 and Figure 8).

Figure 8.

Comparison of MI, PPI, and TDI in three different zones of coal mine region.

9. Trophic diversity index

The value of trophic diversity index of Zone ‘A’ was 1.17 ± 0.02 (1.06–1.32), while those of Zone ‘B’ and Zone ‘C’ were 1.09 ± 0.04 (1.04–1.25) and 1.00 ± 0.00 (1.04–1.25), respectively (Table 8 and Figure 8).

Variables	Bac. Sp	Fung. Sp	Herb. Sp	Omi. Sp	Pred. sp.	MI	PPI	TDI	SI	EI	BI	CI	NCR	Tot. Indv.	pH	BD	Porosity	SM	WHC	ToC	TSN	Avail. K	EC
Bac. Sp	1	0.996	0.997	0.872	0.991	0.949	0.999	0.898	0.983	0.705	−0.861	0.884	0.982	0.886	0.988	−0.986	−0.850	0.944	0.996	0.943	0.932	0.534	−0.804
Fung. Sp	0.996	1	1.000	0.910	0.999	0.972	0.999	0.932	0.995	0.643	−0.901	0.920	0.963	0.921	0.998	−0.996	−0.891	0.968	1.000	0.968	0.899	0.603	−0.851
Herb. Sp	0.997	1.000	1	0.905	0.998	0.969	1.000	0.927	0.994	0.653	−0.896	0.915	0.967	0.917	0.997	−0.995	−0.885	0.965	1.000	0.964	0.904	0.593	−0.844
Omi. Sp	0.872	0.910	0.905	1	0.931	0.982	0.892	0.999	0.948	0.269	−1.000	1.000	0.766	1.000	0.937	−0.942	−0.999	0.985	0.914	0.985	0.636	0.879	−0.992
Pred. sp.	0.991	0.999	0.998	0.931	1	0.983	0.996	0.950	0.999	0.602	−0.923	0.939	0.948	0.941	1.000	−0.999	−0.914	0.980	0.999	0.980	0.874	0.644	−0.877
MI	0.949	0.972	0.969	0.982	0.983	1	0.961	0.991	0.991	0.445	−0.978	0.986	0.873	0.987	0.986	−0.988	−0.973	1.000	0.974	1.000	0.770	0.774	−0.951
PPI	0.999	0.999	1.000	0.892	0.996	0.961	1	0.916	0.990	0.675	−0.882	0.903	0.974	0.905	0.994	−0.992	−0.871	0.957	0.999	0.956	0.916	0.569	−0.828
TDI	0.898	0.932	0.927	0.999	0.950	0.991	0.916	1	0.964	0.321	−0.997	1.000	0.800	1.000	0.955	−0.959	−0.995	0.993	0.935	0.993	0.678	0.852	−0.984
SI	0.983	0.995	0.994	0.948	0.999	0.991	0.990	0.964	1	0.562	−0.940	0.955	0.931	0.956	1.000	−1.000	−0.933	0.989	0.996	0.988	0.849	0.681	−0.900
EI	0.705	0.643	0.653	0.269	0.602	0.445	0.675	0.321	0.562	1	−0.247	0.291	0.825	0.295	0.588	−0.576	−0.226	0.432	0.636	0.429	0.914	−0.223	−0.145
BI	−0.861	−0.901	−0.896	−1.000	−0.923	−0.978	−0.882	−0.997	−0.940	−0.247	1	−0.999	−0.751	−0.999	−0.929	0.935	1.000	−0.981	−0.905	−0.981	−0.619	−0.889	0.995
CI	0.884	0.920	0.915	1.000	0.939	0.986	0.903	1.000	0.955	0.291	−0.999	1	0.781	1.000	0.945	−0.950	−0.998	0.989	0.923	0.989	0.654	0.868	−0.989
NCR	0.982	0.963	0.967	0.766	0.948	0.873	0.974	0.800	0.931	0.825	−0.751	0.781	1	0.783	0.942	−0.937	−0.737	0.866	0.961	0.864	0.983	0.367	−0.678
Tot. Indv.	0.886	0.921	0.917	1.000	0.941	0.987	0.905	1.000	0.956	0.295	−0.999	1.000	0.783	1	0.946	−0.951	−0.997	0.989	0.925	0.990	0.658	0.866	−0.988
pH	0.988	0.998	0.997	0.937	1.000	0.986	0.994	0.955	1.000	0.588	−0.929	0.945	0.942	0.946	1	−1.000	−0.921	0.983	0.998	0.983	0.866	0.657	−0.886
BD	−0.986	−0.996	−0.995	−0.942	−0.999	−0.988	−0.992	−0.959	−1.000	−0.576	0.935	−0.950	−0.937	−0.951	−1.000	1	0.926	−0.986	−0.997	−0.986	−0.858	−0.669	0.892
Porosity	−0.850	−0.891	−0.885	−0.999	−0.914	−0.973	−0.871	−0.995	−0.933	−0.226	1.000	−0.998	−0.737	−0.997	−0.921	0.926	1	−0.976	−0.895	−0.977	−0.602	−0.899	0.997
SM	0.944	0.968	0.965	0.985	0.980	1.000	0.957	0.993	0.989	0.432	−0.981	0.989	0.866	0.989	0.983	−0.986	−0.976	1	0.971	1.000	0.760	0.783	−0.955
WHC	0.996	1.000	1.000	0.914	0.999	0.974	0.999	0.935	0.996	0.636	−0.905	0.923	0.961	0.925	0.998	−0.997	−0.895	0.971	1	0.970	0.894	0.610	−0.856
ToC	0.943	0.968	0.964	0.985	0.980	1.000	0.956	0.993	0.988	0.429	−0.981	0.989	0.864	0.990	0.983	−0.986	−0.977	1.000	0.970	1	0.759	0.785	−0.956
TSN	0.932	0.899	0.904	0.636	0.874	0.770	0.916	0.678	0.849	0.914	−0.619	0.654	0.983	0.658	0.866	−0.858	−0.602	0.760	0.894	0.759	1	0.192	−0.534
Avail. K	0.534	0.603	0.593	0.879	0.644	0.774	0.569	0.852	0.681	−0.223	−0.889	0.868	0.367	0.866	0.657	−0.669	−0.899	0.783	0.610	0.785	0.192	1	−0.932
EC	−0.804	−0.851	−0.844	−0.992	−0.877	−0.951	−0.828	−0.984	−0.900	−0.145	0.995	−0.989	−0.678	−0.988	−0.886	0.892	0.997	−0.955	−0.856	−0.956	−0.534	−0.932	1

Table 8.

Correlation coefficient among the various variables used for nematode community analysis.

10. Weighted faunal analysis

The indices calculated depended on weighted nematode indicator guilds [1, 12] to assess the level of organic enrichment (EI), the decomposition pathways (CI) (Table 8 and Figure 9), the basal/minimal level of resource utilization (BI) and the structured status or stability of ecosystem (SI). In Zone ‘A’ the structure index (SI) was highest i.e., 68.23 ± 10.20 (58.30–77.43), while in Zone ‘B’ the SI value was calculated to be 45.15 ± 5.85 (40.68–52.68) and in Zone ‘C’ the SI was zero. On the contrary, the enrichment index (EI) was calculated to be 12.62 ± 4.66 (7.65–32.25), 22.62 ± 12.58 (16.53–64.65) and 9.54 ± 1.54 (9.50–10.56) in Zone ‘A’, Zone ‘B’ and Zone ‘C’, respectively. The values of basal index (BI) for three different Zones were 74.46 ± 3.25 (70.13–78.16) in Zone ‘C’ followed by value of 57.29 ± 8.10 (44.24–67.35) in Zone ‘B’; lowest value of BI was observed in 41.28 ± 12.30 (32.04–62.05) in Zone ‘A’. The values of channel index (CI) in Zone ‘A’ and Zone ‘B’ were 0.31 ± 0.40 (0.25–0.84) and 0.54 ± 0.42 (0.50–1.24), respectively while CI was incalculable in Zone ‘C’ (Table 8 and Figure 10).

Figure 9.

Comparison of CI and NCR in three different zones of coal mine region.

Figure 10.

Comparison of SI, EI, and BI in three different zones of coal mine region.

In faunal ordination graph between structure index and enrichment index, it was observed that in Zone ‘A’ the mean values were placed in quadrat ‘C’ whereas the mean values for Zone ‘B’ were at the interjunction of quadrat ‘A’ and quadrat ‘C’. In Zone ‘C’ the soil had almost no vegetation, low nutrient, and very little organic carbon (Figure 11).

Figure 11.

Faunal profiles representing the food-web condition in relation to its structure (SI) and enrichment (EI) as indicated by the “weighted faunal analysis” (mean ± SE).

11. Correlations among different variables

The Principal component analysis (PCA) was carried out and a correlation circle was retrieved (Figure 12), which depicted the correlations among various variables. Structure index (SI) showed a positive correlation with number of bacterivores species (r = 0.98, p < 0.05), fungivores (r = 0.99, p < 0.05), and herbivores (r = 0.99, p < 0.05), omnivores (r = 0.94, <0.05) and predators (r = 0.99, p < 0.05). Almost all the trophic groups showed a positive relationship with SI. Structure index also showed a positive correlation with PPI (r = 0.99, p < 0.05), pH (r = 1.00, p < 0.05), TDI (r = 0.96, p < 0.05), NCR (r = 0.93, p < 0.05) and MI (r = 0.99, p < 0.05). SI also depicted low positive relationship EI (r = 0.56, p < 0.05) and strong negative correlation with CI (r = 0.99, p < 0.05) and BI (r = −0.94, p < 0.05). EI showed strong negative correlation with CI and BI all at (p < 0.05). All trophic groups showed a positive correlation among themselves (p < 0.05) and also with PPI, pH, and MI. Among the trophic groups, only bacterivores showed robust positive correlation with EI (r = 0.70, p < 0.05). EI did not show any correlation with PPI, nonsignificant correlation with SI and significant positive correlation with MI. Soil organic carbon was significantly positively correlated with all trophic groups (p < 0.05) and show a negative correlation with electrical conductivity, porosity, basal index and bulk density (Table 8 and Figure 13).

Figure 12.

Biplot correlation circle depicting the correlation among the different variables.

Figure 13.

Biplot ordination (PCA) of observation dates on trophic groups abundance in terms of species, total nematode abundance and various other variables with respect three different zones in coal mine region.

In Biplot ordination graph the three Zones can be clearly differentiated with respect to biotic and abiotic variables and can be superimposed on the anthropogenic disturbances to assess its impact.

12. Discussion

Human activities disturb the soil ecosystem and affect soil nematode diversity [8, 23, 24, 25]. The effect is well reflected in present study where there is a significant impact on below-ground soil biodiversity with special reference to nematodes. The transition from aboveground plant heterogeneity in natural forests to extreme loss of vegetation due to mining activities is reflected in the changed community characteristics of soil nematodes and in their species diversity.

In Zone ‘A’, the number of species (species richness) was greater, but species dominance was low while in Zone ‘B’, an intermediate value of species richness with high species dominance of bacterial-feeders was recorded. These species viz., Achromadora porosus sp. n., Acrobeloides nanus and Acrobeles cylindricus showed tolerance to environmental stress, seasonal anhydrobiosis and other anthropogenic disturbances. Further, Zone ‘B’ represented the reclaimed 21 years old coal mine spoil with some incorporation of amendments to enrich the soil thus another reason for abundance of bacterivores. In Zone ‘C’ only three species were found viz., Mesorhabditis tenuhystera sp. n., Mesorhabditis vernalis and Acrobeloides nanus. As, Zone ‘C’ was the active site for mining and with constant disturbances, the soil was almost lifeless with no nutrients and the area simply represented old exposed rocks mixed with coal dust having little organic carbon. The chemical residue from blasting and heavy metal contamination from mining process hindered the growth of plants and animals. The rhabditid species (cp-1) found in active mining Zone ‘C’, were enrichment opportunists and might have passively reached the active mining site via wind, water or through phoresis [26]. However, their sustenance showed their greater tolerance abilities towards mineral and industrial waste materials [27]. Thus Mesorhabditis spp. demonstrated greater endurance. In unfavorable periods, production of dauer larvae was the possible survival strategy for these enrichment opportunists. Zone ‘B’, the relatively less disturbed site, might have initially shown the growth of zymogenous (fast growing) microflora on fossil organic carbon that formed food for the microbivorous species, a condition also noticed by Háněl [28] who reported the abundant populations of genera Acrobeloides and Aphelenchoides. Zone ‘A’ consisting of natural wild forest, showed heterogenetic topography, and the litter accumulation due to undulating surfaces, was the reason for relatively high diversity and abundance of all trophic groups including bacterivores with values of both Simpson’s index and Shannon’s index comparable to any natural forest [23, 29, 30, 31, 32].

Although there was not a major difference between the total number of species of fungivores and herbivores in Zone ‘A’ and Zone ‘B’, the mean abundance of both the trophic groups was much high in Zone ‘A’. Despite the fact that stable ecosystems like Zone ‘A’ demonstrated species diversity and evenness, very often the species diversity has been reported to be greater in habitats subject to intermediate levels of disturbance because stochastic, intermediate (partial) elimination of resources by disturbance leads to species-specific mortality allowing the co-existence of competitively inferior species [33]. The combination of intermediate level of disturbance with intermediate productivity levels demonstrated a peak in species richness, not only due to periodic decreases of competitively dominant species but also to increased niche packing [34]. Structurally, complex environments thus provide more niches thereby increasing species diversity [35]. In conformity with the earlier reports on increased diversity at intermediate disturbance [36, 37, 38] and a positive relationship between habitat complexity and species diversity [39, 40, 41, 42, 43, 44], Zone B demonstrated similar status. It showed an intermediate level of disturbances and the species diversity too was somewhat closer to Zone A which represented undisturbed zone. Large mononchid and large dorylaimoid nematodes with higher c-p values were mostly missing from Zone ‘B’ (Table 5), except for Discolaimus major and Discolaimoides bulbiferous which constituted the predator group along with another low c-p value predator and disturbance or enrichment indicator Mononchoides longicauda. Zone ‘C’ simply represented bacterivore colonizers with c-p values 1 and 2. Thus the nematode community structure in the selected zones showed typical examples of maturity and species diversification with respect to anthropogenic disturbances.

The maturity index of Zone ‘A’ Zone ‘B’ did not show much difference and could well indicate the status of Zone ‘A’ as structured and mature type of ecosystem and Zone ‘B’ as moderately structured and maturing type. Zone ‘C’ was obviously a highly disturbed region because of mining activities. These results agree well with those reported by Háněl [28] on coal mines.

The faunal profile results also corresponded with MI values of Zone ‘A’ and Zone ‘B’ as both reflected the dominant fungal decomposition pathways whereas Zone ‘C’ with disturbed and degraded food web demonstrated bacterial decomposition channels.

Although the present study has provided some pertinent information related to nematodes found in coal mine areas and the differences in nematode communities and their gradual succession in different overburdens or spoils, a detailed discussion on the role of individual species could not be done due to space constraint. Nevertheless, it is clearly evident that nematode assemblages can be evaluated and can serve as excellent tools for environmental monitoring or environment quality assessment. The study has opened up avenues for more studies to be conducted in coal mine areas using nematodes as models. Also, future studies in this direction may further vouch for comparison and may indicate any specificity or association of nematode taxa to coal mine areas. Such information may also have predictive value about the specificity and occurrence of species in degraded habitats, early successional and late successional stages to undisturbed habitats and can be used in modeling and predicting future changes in biodiversity and species interactions with land use changes.

13. Conclusion

In conclusion, this study highlights the significant impact of human activities on soil nematode diversity, particularly in the context of mining activities. The transition from natural forests to mining sites results in notable changes in soil nematode communities and species diversity.

In Zone ‘A’, which represents undisturbed natural forests, there is a higher species richness and lower species dominance among nematodes. In Zone ‘B’, which is a reclaimed coal mine spoil with some soil enrichment measures, there is an intermediate level of species richness but a higher dominance of bacterial-feeders. These nematode species in Zone ‘B’ exhibit tolerance to environmental stress and anthropogenic disturbances. On the other hand, Zone ‘C’, an actively mined area with constant disturbances and little organic matter, contains only a few nematode species, primarily enrichment opportunists with a high tolerance for mineral and industrial waste materials.

The study also suggests that intermediate levels of disturbance, as seen in Zone ‘B’, can lead to increased species diversity due to periodic decreases of dominant species and increased niche packing. Habitat complexity, as observed in both Zone ‘A’ and Zone ‘B’, also contributes to higher species diversity.

The maturity index values of Zone ‘A’ and Zone ‘B’ indicate structured and mature ecosystems, while Zone ‘C’ represents a highly disturbed and degraded region due to mining activities. The faunal profile results align with the maturity index values, with Zone ‘A’ and Zone ‘B’ dominated by fungal decomposition pathways and Zone ‘C’ characterized by bacterial decomposition channels.

While this study provides valuable insights into nematode communities in coal mine areas, further research is needed to explore the roles of individual nematode species in these ecosystems. Nematodes can serve as excellent indicators for environmental monitoring and assessing environmental quality. Future studies in this area may reveal specific associations of nematode taxa with coal mine areas, aiding in biodiversity modeling and predicting how species interactions change with land use alterations. This research opens the door to a deeper understanding of the impact of human activities on soil ecosystems and the potential for ecological restoration efforts.