Table 1. Details of the sediment samples from different wetlands Including geographic location, physiochemical characteristics, numbers of different OTUs and biodiversity. (Shannon diversity index, Simpson's reciprocal index, Pielou index and functional organization values were calculated based on a culture-dependent method and a DGGE method).

Sites	Code	Statusa	Changjiang Riverb	Longitude	Latitude	Altitude	Organic matter (g kg−1)	Organic C (g kg−1)	Total N (g kg−1)	Total P (g kg−1)	Total K (g kg−1)	C/N
Zhalong Wetland	ZLW	NC	N	124.5	47.3	142.5	54.78±18.52	31.78±10.74	2.99±1.10	0.65±0.13	20.33±0.83	10.88±1.23
Mengjiaduan Reservior	MJD	NC	N	121.0	43.4	276.0	6.64±4.55	3.85±2.64	0.19±0.04	0.17±0.03	24.13±0.89	19.51±8.76
Baxiantong Marsh	BXT	NC	N	121.0	43.3	275.0	10.47±4.08	6.07±2.37	0.62±0.29	0.23±0.09	25.80±0.05	10.07±0.86
Laoha Lake	LHH	NC	N	120.6	42.9	311.0	15.26±3.54	8.85±2.67	0.96±0.30	0.34±0.05	22.38±0.42	9.43±1.60
Bosten Lake	BL	NC	N	86.8	42.0	1048.0	32.60±6.28	18.91±3.64	1.73±1.69	0.69±0.19	17.81±1.44	16.72±8.87
Baiyangdian Lake	BYD	NC	N	115.9	38.8	18.0	23.48±4.80	13.62±2.78	2.56±1.60	0.87±0.16	18.26±0.69	6.18±2.08
Qinghai Lake	QHL	QTP	N	100.2	36.8	3100.0	7.27±0.31	4.22±0.18	0.31±0.01	0.52±0.14	18.18±7.77	13.63±0.14
Gahai Lake	GHL	QTP	N	102.3	34.2	3200.0	36.13±2.16	20.96±1.25	2.53±0.73	0.65±0.31	14.82±1.78	8.58±2.00
Zoige Wetland	ZW	QTP	Y	103.0	33.6	3461.0	48.10±6.30	27.90±3.65	2.47±0.45	0.89±0.03	20.08±0.57	11.35±0.87
Zoige Marsh	ZM	QTP	Y	103.0	33.6	3456.0	29.67±2.43	17.21±1.41	1.32±0.25	1.42±0.13	12.80±0.65	13.38±3.18
Nanjing River	NJR	SC	Y	118.0	32.2	8.9	14.51±11.69	8.42±6.78	0.84±0.47	0.78±0.26	21.25±0.22	9.17±2.90
Dong Lake	DL	SC	Y	114.4	30.5	23.3	23.88±1.35	13.85±0.78	1.66±0.16	0.46±0.01	17.16±0.07	8.38±0.32
Xixi Wetland	XXW	SC	Y	120.1	30.3	8.0	17.88±5.64	10.37±3.27	0.95±0.22	0.82±0.18	16.88±2.48	10.83±0.99
Zimei Lake	ZML	QTP	Y	99.1	30.0	3800.0	22.06±0.10	12.80±0.06	0.78±0.01	0.51±0.08	17.07±7.55	16.33±0.11
Jinhuajiang River	JHR	SC	Y	119.2	29.1	49.0	13.33±10.27	7.73±5.96	0.90±0.49	0.60±0.38	29.71±2.79	8.20±3.08
Sourth Dongting Lake	SDT	SC	Y	113.0	29.4	35.0	19.17±0.41	11.12±0.24	1.12±0.06	0.87±0.00	22.96±0.08	9.90±0.30
Poyang Lake	PYL	SC	Y	116.1	29.2	16.0	26.49±3.61	15.37±2.09	1.40±0.15	0.64±0.30	23.97±2.07	11.09±1.85
East Dongting Lake	EDT	SC	Y	112.4	28.9	45.0	14.26±6.39	8.27±3.71	0.80±0.43	0.47±0.22	22.13±2.74	10.62±1.02
Dali West Lake	WL	SC	N	100.1	26.0	2069.0	103.06±3.82	59.78±2.21	5.26±0.35	0.43±0.01	6.87±0.86	11.38±0.33
Guangdong Mangrove	GDM	SC	N	110.1	20.9	15.0	52.55±6.14	30.48±3.56	1.96±0.30	0.76±0.13	13.75±2.36	15.72±2.56

Sites	Code	C/P	pH	Temperature (ºC)	Culture-independent method					Culture-dependent method
					H′	1/D	E	Fo	OTUs	H′	1/D	E	Fo	OTUs	Isolates
Zhalong Wetland	ZLW	47.58±8.74	8.75±0.11	21.1	2.80±0.25	14.52±4.80	0.91±0.06	0.70±0.09	27	2.1	3.82	0.67	0.79	22	57
Mengjiaduan Reservior	MJD	21.58±12.23	7.34±0.22	23.3	2.72±0.04	13.24±0.58	0.90±0.01	0.76±0.02	22	2.18	12.67	0.95	0.72	10	23
Baxiantong Marsh	BXT	26.88±0.40	7.36±0.22	23.3	2.86±0.11	15.31±2.25	0.92±0.01	0.73±0.04	25	1.43	4.29	0.89	0.78	5	21
Laoha Lake	LHH	26.14±3.10	7.32±0.22	23.3	2.83±0.09	14.12±2.23	0.90±0.03	0.78±0.04	25	2.25	1.39	0.94	0.74	12	35
Bosten Lake	BL	29.46±10.91	8.63±0.12	22.9	2.38±0.10	8.40±0.90	0.81±0.03	0.86±0.04	22	2.49	13.27	0.92	0.72	15	46
Baiyangdian Lake	BYD	32.25±33.27	8.00±0.15	21.3	2.67±0.17	11.59±2.29	0.86±0.05	0.80±0.05	27	3.23	29.08	0.94	0.73	31	76
Qinghai Lake	QHL	8.42±2.53	8.49±0.15	15.4	2.59±0.11	11.48±1.27	0.91±0.06	0.70±0.10	22	1.88	7	0.9	0.8	8	22
Gahai Lake	GHL	36.86±19.67	7.77±0.13	15.4	2.34±0.04	7.65±0.48	0.80±0.03	0.86±0.02	19	2.38	13.18	0.93	0.77	13	30
Zoige Wetland	ZW	31.24±3.22	7.06±0.16	12.5	2.47±0.16	9.02±1.78	0.83±0.05	0.85±0.02	19	2.37	17.27	0.95	0.79	12	20
Zoige Marsh	ZM	12.16±0.16	6.50±0.10	12.5	2.27±0.06	7.17±0.65	0.79±0.02	0.86±0.02	20	2.55	17.5	0.97	0.75	15	36
Nanjing River	NJR	9.87±5.35	6.78±0.16	27.2	2.67±0.19	12.47±2.10	0.89±0.00	0.78±0.02	17	2.96	19.5	0.93	0.76	25	95
Dong Lake	DL	29.95±0.82	6.82±0.19	29.1	2.58±0.33	11.51±3.87	0.88±0.01	0.79±0.04	25	2.58	16.25	0.95	0.69	15	42
Xixi Wetland	XXW	13.40±6.87	6.45±0.13	28.4	2.89±0.08	15.62±0.18	0.92±0.03	0.71±0.07	26	2.25	8.67	0.88	0.74	13	40
Zimei Lake	ZML	25.25±3.94	5.87±0.16	17.5	2.22±0.37	6.44±2.55	0.78±0.05	0.79±0.02	21	2.23	9	0.87	0.78	13	36
Jinhuajiang River	JHR	11.65±3.00	6.72±0.13	30.6	2.67±0.21	11.91±3.22	0.88±0.04	0.76±0.05	24	2.83	19.15	0.94	0.68	20	66
Sourth Dongting Lake	SDT	12.73±0.25	8.32±0.02	29.4	2.92±0.02	15.74±0.23	0.92±0.01	0.73±0.01	25	2.34	12.35	0.94	0.83	11	33
Poyang Lake	PYL	27.50±11.61	7.79±0.05	30.7	2.70±0.20	12.31±5.01	0.89±0.06	0.73±0.09	23	3.23	23.93	0.92	0.78	34	109
East Dongting Lake	EDT	17.53±2.78	6.94±0.10	29.4	2.62±0.13	10.95±2.08	0.89±0.04	0.76±0.03	19	2.43	10.93	0.9	0.88	15	41
Dali West Lake	WL	138.42±3.40	7.42±0.11	20.6	2.58±0.33	11.51±3.87	0.88±0.01	0.79±0.04	25	1.83	6.65	0.88	0.74	9	18
Guangdong Mangrove	GDM	40.31±4.58	6.70±0.05	30.6	2.39±0.10	8.55±0.82	0.85±0.01	0.80±0.04	19	2.62	18	0.95	0.78	16	37

^aSC, NC and QTP refer to Southern China, Northern China and the Qinghai-Tibetan Plateau in Western China, respectively.

^bY refers to wetlands associated with the Changjiang River, while N refers to wetlands not associated with the Changjiang River.