Growth responses and adaptations of the emergent macrophyte Acorus calamus Linn. to different water-level fluctuations

Figures & data

Figure1. A graph of the experimental system with water depth (cm) on the y-axis. Each treatment was replicated three times in outdoor ponds (3.0 m long × 1.4 m wide × 1.5 m deep) and the water levels in the fluctuating depth treatments occurred every week.

Table1 Water physical and chemical conditions during the experiment.

Parameter	Mean ± SD	Range
Water temperature (°C)	28.6 ± 1.7	26.5–30.3
Illumination (lx)	4146 ± 674	2831–6067
pH	7.69 ± 0.51	6.53–7.91
Total suspended solid (TSS) (mg L^−1)	2.28 ± 0.47	2.08–2.37
DO (mg L^−1)	8.22 ± 0.32	7.90–8.36
Chl a (μg L^−1)	1.53 ± 0.47	1.41–1.98
Electrical conductivity (EC) (μS cm^−1)	247.3 ± 8.3	222.5–278.4
Total dissolved solid (TDS) (mg L^−1)	760.2 ± 1.3	758.3–763.9
Transparency SD (cm)	107.8 ± 23.1	92.3–150.0
Oxidation-reduction potential (ORP) (mV)	−98.7 ± 11.2	−82.2 to –130.9
Turbidity [Nephelometric turbidity unit (NTU)]	1.95 ± 0.63	1.39–2.35
TN (mg L^−1)	2.20 ± 0.58	1.92–2.54
TP (mg L^−1)	0.395 ± 0.097	0.220–0.405

Figure2. Changes in mean blade length, shoot length, shoot number, and shoot width per pot over time in Acorus calamus subjected to four water-level fluctuation treatments (0 cm, 60 cm, 60 ± 30 cm, and 60 ± 60 cm). Each cycle was 2 weeks in duration.

Figure3. Changes in total biomass and biomass allocation of Acorus calamus subjected to four water-level fluctuation treatments (0 cm, 60 cm, 60 ± 30 cm, and 60 ± 60 cm). All the values were means of triplicates ± SD. Different letters within a tissue category signify significant differences.

Figure4. Differences in mean ratio of root dry matter to shoot dry matter production (R:S, top panel), mean fractional number of chlorotic leaves (yellow leaf ratio, middle panel), and mean relative growth rate (RGR, bottom panel) in Acorus calamus subjected to four water-level fluctuation treatments (0 cm, 60 cm, 60 ± 30 cm, and 60 ± 60 cm). Error bars represent 1 SD. Different letters within a graph indicate significant differences among treatments.

Figure5. The length, diameter and number of rhizomes in Acorus calamus subjected to four water-level fluctuation treatments (0 cm, 60 cm, 60 ± 30 cm, and 60 ± 60 cm). All the values were means of triplicates ± SD. Different letters within a graph indicate significant differences among treatments.

Figure6. The length, diameter and number of roots in Acorus calamus subjected to four water-level fluctuation treatments (0 cm, 60 cm, 60 ± 30 cm, and 60 ± 60 cm). All the values were mean of triplicates ± SD. Different letters within a graph indicate significant differences among treatments.

Figure7. Effects of four water-level fluctuation treatments (0 cm, 60 cm, 60 ± 30 cm, and 60 ± 60 cm) on tissue proline and MDA concentration in Acorus calamus for each two-week cycle. All the values were means of triplicates ± SD.

Figure8. Effects of four water-level fluctuation treatments (0 cm, 60 cm, 60 ± 30 cm, and 60 ± 60 cm) on chlorophyll a content in Acorus calamus. All the values are means of triplicates ± SD.

Figure9. The soluble sugar concentrations of shoot, rhizome, and root in Acorus calamus in four water-level fluctuation treatments (0 cm, 60 cm, 60 ± 30 cm, and 60 ± 60 cm). All the values were means of triplicates ± SD. Different letters within a graph indicate significant differences among treatments.