Assessing impact of acid mine drainage on benthic macroinvertebrates: can functional diversity metrics be used as indicators?

Figures & data

Figure 1. Locations of the abandoned pyrite mines and the sampling sites.

Table 2. Observed functional groups at sampling sites.

Functional group		Example genera
Filterers	Climbers	Tanytarsus
Filterers	Clingers	Ceratopsyche, Hydropsyche
Gatherers	Burrowers	Ephemera
Gatherers	Clingers	Ephemerella, Antocha
Gatherers	Sprawlers	Caenis, Setodes
Gatherers	Swimmers	Baetis, Leptophlebia
Predators	Burrowers	Bezzia
Predators	Climbers	Planaeschna
Predators	Clingers	Isoperla, Neoperla
Predators	Sprawlers	Atherix, Hemerodromia
Predators	Swimmers	Liodessus
Scrapers	Climbers	Cyphon
Scrapers	Clingers	Heptagenia, Deuterophlebia
Scrapers	Sprawlers	Psilotreta
Scrapers	Swimmers	Habrophlebiodes
Shredders	Burrowers	Tipula
Shredders	Climbers	Goerodes, Trichosetodes
Shredders	Clingers	Micrasema, Cricotopus
Shredders	Sprawlers	Nemoura, Amphinemura

Table 3. Mean and standard deviation (SD) of pH and metal concentrations at sampling sites.

	Control sites	Impacted sites	Recovered sites
pH	8.32 ± 0.26^a	5.22 ± 1.32^b	7.93 ± 0.92^a
Al (μg·L^−1)	43.10 ± 60.62^a	4052.68 ± 4243.12^b	52.27 ± 29.53^a
Cu (μg·L^−1)	3.80 ± 2.79^a	12.49 ± 8.93^a	3.72 ± 2.10^a
Fe (μg·L^−1)	39.23 ± 55.73^a	1437.20 ± 2544.27^b	27.28 ± 29.86^a
Mn (μg·L^−1)	0.90 ± 1.07^a	457.38 ± 282.12^b	36.37 ± 36.83^c
Zn (μg·L^−1)	8.75 ± 5.46^a	30.32 ± 23.11^b	6.68 ± 3.67^a

Note: Different letters (a, b, and c) above each result depict significant difference (Mann–Whitney U test, p < 0.05).

Figure 2. Density of macroinvertebrates at sampling sites.

Table 4. Mean and standard deviation (SD) of macroinvertebrate metrics at sampling sites.

	Control sites		Impacted sites		Recovered sites
Index	Mean	SD	Mean	SD	Mean	SD
Functional richness	12.83^a	1.17	1.17^b	1.17	10.50^a	2.35
Functional Shannon's index	1.83^a	0.14	0.23^b	0.36	1.50^c	0.30
Functional Brillouin's index	1.81^a	0.14	0.17^b	0.27	1.47^c	0.31
Richness	37.67^a	5.35	2.17^b	1.17	28.83^a	10.40
Shannon's index	3.43^a	0.16	1.23^b	0.36	3.06^a	0.49
Brillouin's index	3.38^a	0.15	1.16^b	0.27	3.00^a	0.50
AMD' index	37.35^a	6.20	2.74^b	1.37	29.59^a	10.53
BMWP score	107.50^a	11.95	5.83^b	5.15	82.00^a	30.23

Note: Different letters (a, b, and c) above each result depict significant difference (Mann–Whitney U test, p < 0.05).

Table 5. Pearson correlations of functional diversity metrics against AMD parameters.

	pH	Al	Cu	Fe	Mn	Zn	Average r
Functional richness	0.845***	−0.677**	−0.689**	−0.483*	−0.836***	−0.681**	0.702
Functional Shannon's index	0.816***	−0.704**	−0.740***	−0.499*	−0.838***	−0.708**	0.718
Functional Brillouin's index	0.820***	−0.685**	−0.716**	−0.482*	−0.832***	−0.690**	0.704
Richness	0.829***	−0.600**	−0.578*	−0.416	−0.778***	−0.582*	0.631
Shannon's index	0.822***	−0.684**	−0.716**	−0.481*	−0.832***	−0.694**	0.705
Brillouin's index	0.821***	−0.667**	−0.697**	−0.466	−0.825***	−0.678**	0.692
AMD' index	0.815***	−0.607**	−0.589*	−0.426	−0.781***	−0.594**	0.635
BMWP score	0.776***	−0.620**	−0.648**	−0.432	−0.789***	−0.635**	0.650

Note: The levels of significance are ***p < 0.001, **p < 0.01, *p < 0.05.

Figure 3. Proportion of functional groups at sampling sites.

Figure 4. Biomass of benthic algae (measuring with Ch1a) at sampling sites.

Table 1. Elevation, mean of channel width and water depth at sampling sites.

	Elevation (m)	Width (m)	Depth (m)
C1	770	3.69	0.16
C2	672	8.32	0.17
C3	652	7.55	0.26
I1	767	4.22	0.17
I2	717	10.03	0.15
I3	642	7.30	0.22
R1	580	13.80	0.28
R2	480	8.00	0.26
R3	381	14.28	0.20