Biodiversity and distribution of zoobenthos in the ecological water replenishment area of the Yellow River estuary coastal wetland revealed by eDNA metabarcoding

The circos chart in Fig 2A highlights significant differences in zoobenthic species composi- tion across sampling points S1 to S16. Each sampling point is represented by a segment in the outer circle, with color-coded bars denoting the relative abundance of various species families. The inner chords illustrate transitions and interactions between species groups across these points. Notable variations are observed, with Limnocytheridae and Typhloplanidae being more prevalent at point S11. Additionally, Xyalidae are prominent at points S6 and S7, while Schizocytheridae show higher presence at points S2, S13, and S14. These patterns suggest dis- tinct ecological niches or environmental conditions influencing species distribution at differ- ent sampling points. The Venn diagram in Fig 2B illustrates the species composition differences at the family level across 16 sampling points. The central "core 39" represents 39 species common to all sampling points. Each petal indicates the number of unique species for each respective sample. For example, sample S3 has 56 unique species, S14 has 46, and both S9 and S8 have 48 unique species each. The total number of species in each sample is calculated by adding the core value (39) to the unique species count. Thus, S3 contains 95 species (39 core + 56 unique), and S14 has 85 species (39 core + 46 unique). Although the data on shared species between different points is not shown, the diagram effectively highlights both the diver- sity and commonality of species across the sampling points, emphasizing the ecological rich-

ness and variation within the zoobenthic ecosystem. Table 1. Water quality parameters of samples taken from the Yellow River Estuary Coastal Wetland. Sampling site S1 S2 S3 S4 S5 S6 S7 S8 S9 S10 S11 S12 S13 S14 S15 S16 T (˚C) 19.20 ±0.55 20.40 ±0.05 21.40 ±0.45 21.80 ±0.00 20.10 ±0.10 21.90 ±0.15 21.50 ±0.40 21.10 ±0.16 22.30 ±0.32 19.90 ±0.00 20.60 ±1.05 19.80 ±0.00 21.80 ±0.25 19.50 ±0.12 19.60 ±0.11 19.50 ±0.40 pH 7.85 ±0.67 8.11 ±0.10 8.31 ±0.20 8.46 ±0.23 8.32 ±0.00 9.56 ±0.17 8.68 ±0.17 8.58 ±0.17 8.32 ±0.26 8.61 ±0.02 8.62 ±0.06 8.32 ±0.04 8.94 ±0.18 8.45 ±0.00 8.29 ±0.20 8.31 ±0.35 DO (mg/ L) 5.34 ±1.76 8.08 ±0.05 7.92 ±1.43 9.96 ±2.22 8.91 ±0.06 10.76 ±0.24 10.27 ±0.00 10.82 ±0.35 10.12 ±0.09 9.30 ±0.40 8.58 ±0.47 7.32 ±0.21 9.96 ±0.78 9.41 ±1.97 9.41 ±0.92 9.41 ±1.51 ORP (mv) 87.7 ±139.5 79.8 ±29.6 100.9 ±13.3 118.2 ±4.3 193.7 ±0.1 163.0 ±10.0 165.7 ±13.6 183.5 ±1.3 150.2 ±5.6 149.2 ±10.1 144.7 ±0.7 149.6 ±7.7 159.5 ±7.1 144.4 ±11.9 144.6 ±23.0 144.2 ±18.9 EC (μS/ cm) 26545 ±9167 889±1 1303 ±122 2178 ±819 5921 ±403 1983 ±343 1636 ±42 39870 ±232 44670 ±4 1660 ±159 1224 ±42 1265 ±39 891±10 68470 ±113 52740 ±148 70400 ±5895 TDS (mg/ L) 13270 ±4582 444±2 651±61 1067 ±421 2965 ±204 991 ±171 867±45 19930 ±123 22330 ±5 830±80 614±22 632±20 445±5 37280 ±279 29420 ±72 38250 ±1665 SAL (mg/ L) 1050 ±272 44±0 62±5 103±40 296±3 113±16 77±3 1920 ±123 2180 ±13 79±5 72±1 74±0 55±3 2630 ±49 2690±7 3030 ±80 NH4+-N (mg/L) 1.21 ±0.03 0.09 ±0.00 0.19 ±0.24 0.67 ±0.24 1.10 ±0.01 0.27 ±0.21 0.13 ±0.03 2.03 ±0.92 2.42 ±0.95 0.45 ±0.02 0.32 ±0.06 0.33

±0.00 0.07 ±0.02 0.01 ±0.35 0.02 ±0.20 0.01 ±0.17 TP (mg/L) 0.038 ±0.010 0.004 ±0.044 0.043 ±0.012 0.048 ±0.020 0.053 ±0.002 0.004 ±0.025 0.038 ±0.005 0.098 ±0.012 0.078 ±0.100 0.038 ±0.000 0.033 ±0.000 0.048 ±0.002 0.033 ±0.007 0.112 ±0.001 0.107 ±0.006 0.068 ±0.017 TOC (mg/ L) 23.26 ±4.67 4.36 ±1.73 6.37 ±0.79 5.90 ±2.73 8.65 ±0.35 8.50 ±1.35 6.39 ±0.23 11.92 ±0.95 11.67 ±0.42 8.28 ±0.26 7.45 ±0.44 6.88 ±0.26 5.39 ±0.09 4.69 ±1.47 4.45 ±2.32 4.61 ±3.38 SO42- (mg/ L) 487.5 ±21.5 40.3 ±18.7 147.2 ±10.9 188.0 ±39.5 256.4 ±25.3 188.8 ±6.1 173.6 ±4.9 1024.7 ±15.2 1168.7 ±41.6 161.9 ±10.1 144.6 ±11.6 164.0 ±1.6 125.7 ±55.0 1952.8 ±64.8 1902.3 ±9.3 2267.8 ±31.2 Na+ (mg/ L) 3056 ±731 183±51 171±26 262 ±122 842±45 382±61 26±88 4921 ±205 5580 ±260 223±18 118±33 238±6 131±19 6287 ±140 8616 ±33 8154 ±199 K+ (mg/L) 102.6 ±49.9 13.3 ±1.6 11.7 ±1.3 11.0 ±3.3 36.8 ±2.1 20.3 ±1.9 4.0±5.6 212.7 ±19.2 260.6 ±26.2 13.7 ±0.3 13.5 ±0.3 16.5 ±1.3 11.5 ±1.1 328.6 ±0.2 449.2 ±1.5 405.8 ±6.7 Mg2+ (mg/ L) 419.2 ±105.0 39.8 ±10.2 42.9 ±5.0 48.8 ±29.0 119.0 ±5.8 2.6 ±26.0 8.7 ±19.6 546.0 ±26.3 627.8 ±29.2 49.0 ±1.8 46.2 ±1.2 52.0 ±2.6 32.6 ±5.1 748.5 ±28.1 996.5 ±6.2 605.5 ±28.9 Ca2+ (mg/ L) 213.3 ±58.6 104.4 ±22.3 48.1 ±1.6 46.4 ±23.1 107.7 ±4.6 36.2 ±3.1 9.3 ±14.0 268.9 ±3.2 302.3 ±5.1 49.0 ±6.0 37.1 ±1.5 33.1 ±5.4 35.5 ±0.3 315.5 ±18.1 427.8 ±3.4 271.7 ±20.7 https://doi.org/10.1371/journal.pone.0315346.t001 PLOS ONE Biodiversity and zoobenthos distribution in yellow river estuary wetlands revealed by eDNA metabarcoding

PLOS ONE | https://doi.org/10.1371/journal.pone.0315346 December 18, 2024 7 / 19