Hydrochemical characteristics and controlling factors of natural water in the border areas of the Qinghai-Tibet Plateau

doi:10.1007/s11442-019-1994-y

Abstract

Abstract:

The special geography and human environment of the Qinghai-Tibet Plateau has created the unique hydrochemical characteristics of the region’s natural water, which has been preserved in a largely natural state. However, as the intensity of anthropogenic activities in the region has continued to increase, the water environment and hydrochemical characteristics of the Qinghai-Tibet Plateau have altered. In this study, water samples from the western, southern, and northeastern border areas of the Qinghai-Tibet Plateau, where human activities are ongoing, were collected, analyzed, and measured. The regional differences and factors controlling them were also investigated. The key results were obtained as follows. (1) Differences in the physical properties and hydrochemical characteristics, and their controlling factors, occurred in the different boundary areas of the Qinghai-Tibet Plateau. These differences were mainly the consequence of the geographical environment and geological conditions. (2) The water quality was good and suitable for drinking, with most samples meeting GB (Chinese national) and WHO (World Health Organization) drinking water standards. (3) The chemical properties of water were mainly controlled by the weathering of carbonates and the dissolution of evaporative rocks, with the former the most influential. (4) The biological quality indicators of natural water in the border areas were far superior to GB and WHO drinking water standards.

Key words: border area of the Qinghai-Tibet Plateau, natural water, hydrochemical characteristics, controlling factors

TIAN Yuan, YU Chengqun, ZHA Xinjie, GAO Xing, DAI Erfu. Hydrochemical characteristics and controlling factors of natural water in the border areas of the Qinghai-Tibet Plateau[J].Journal of Geographical Sciences, 2019, 29(11): 1876-1894.

Figures/Tables 13

Figure 1

Table 1

Sampling points of water samples in the border areas of the Qinghai-Tibet Plateau"

No.	Type	Town, County	Latitude (°)	Longitude (°)	Elevation (m)	No.	Type	Town, County	Latitude (°)	Longitude (°)	Elevation (m)
1	Well (14 m)	Zhaxigang, Gaer	32.3722	79.7976	4262	45	Stream	Yalai, Nyalam	28.4159	86.1307	4426
2	Stream	Zhaxigang, Gaer	32.6942	79.4597	4271	46	Stream	Borong, Nyalam	28.7547	85.5842	4643
3	Well (14 m)	Rituzong, Ritu	33.3922	79.7046	4264	47	Stream	Gyirong, Gyirong	28.3950	85.3294	2815
4	Well (15 m)	Risong, Ritu	33.3682	79.6971	4281	48	Stream	Gyirong, Gyirong	28.3952	85.3525	2731
5	Stream	Risong, Ritu	33.1262	79.8355	4359	49	Stream	Gyirong, Gyirong	28.4812	85.2251	3171
6	Stream	Kunsha, Gaer	32.1069	80.0823	4293	50	Stream	Gyirong, Gyirong	28.5006	85.2215	3261
7	Well (10 m)	Tuolin, Zhada	31.4778	79.8051	3712	51	Stream	Gyirong, Gyirong	28.5346	85.2195	3409
8	Well (8 m)	Tuolin, Zhada	31.4757	79.6732	3621	52	Stream	Gyirong, Gyirong	28.5418	85.2285	3510
9	Stream	Daba, Zhada	31.5879	79.9703	4582	53	Stream	Zongga, Gyirong	28.5635	85.2462	3632
10	Stream	Daba, Zhada	31.5314	79.9843	4493	54	Stream	Zongga, Gyirong	28.6056	85.2599	3760
11	Stream	Daba, Zhada	31.4484	80.1229	4693	55	Stream	Zongga, Gyirong	28.6301	85.2691	3736
12	Stream	Menshi, Gaer	31.1789	80.7601	4450	56	Stream	Zongga, Gyirong	28.6533	85.2781	3785
13	Stream	Menshi, Gaer	31.1426	80.9014	4636	57	Stream	Zongga, Gyirong	28.7397	85.2965	3955
14	Well (10 m)	Pulan, Pulan	30.2945	81.1759	3905	58	Stream	Zongga, Gyirong	28.8557	85.2968	4145
15	Well (5 m)	Kejia, Pulan	30.1927	81.2707	3734	59	Stream	Zheba, Gyirong	29.0409	85.4394	4733
16	Stream	Kejia, Pulan	30.2633	81.1870	3891	60	Stream	Zheba, Gyirong	29.2074	85.3636	4527
17	Stream	Namumani, Pulan	30.5157	81.2018	4521	61	Stream	Zhangmu, Nyalam	27.9887	85.9828	2277
18	Stream	Huoer, Pulan	30.6872	81.8323	4752	62	Stream	Zhangmu, Nyalam	27.9903	85.9829	2263
19	Stream	Longzi, Longzi	28.4081	92.4628	3881	63	Stream	Yalai, Nyalam	28.3828	86.1070	4373
20	Stream	Ridang, Longzi	28.6125	92.2153	4998	64	Stream	Nierudui, Kangma	28.4865	89.9269	4569
21	Stream	Zhaxiraodeng, Milin	29.2319	94.0680	2993	65	Stream	Nierudui, Kangma	28.4894	89.9265	4584
22	Stream	Wolong, Milin	29.1447	93.6939	3032	66	Stream	Nierumai, Kangma	28.6419	89.8728	4389
23	Stream	Nanyi, Milin	29.1849	94.1883	2938	67	Stream	Zhangxiong, Kangma	28.6183	89.3708	4489
24	Stream	Nanyi, Milin	29.1279	94.2226	3009	68	Stream	Samada, Kangma	28.3495	89.5377	4447
25	Stream	Nanyi, Milin	29.0417	94.2321	3147	69	Stream	Samada, Kangma	28.2517	89.6455	4573
No.	Type	Town, County	Latitude (°)	Longitude (°)	Elevation (m)	No.	Type	Town, County	Latitude (°)	Longitude (°)	Elevation (m)
26	Stream	Danniang, Milin	29.4613	94.7849	2945	70	Stream	Gala, Kangma	28.2388	89.1817	4474
27	Stream	Pai, Milin	29.5174	94.8811	2931	71	Stream	Kangma, Kangma	28.5587	89.6807	4298
28	Stream	Pai, Milin	29.6977	94.8978	2821	72	Stream	Labuleng, Xiahe	35.1936	102.5151	2942
29	Stream	Jiayu, Longzi	28.2941	92.7492	3380	73	Stream	Sangke, Xiahe	35.0651	102.4624	3207
30	Stream	Liemai, Longzi	28.4247	92.5742	3851	74	Stream	Sangke, Xiahe	35.0126	102.5232	3399
31	Stream	Ridang, Longzi	28.3930	92.1056	4253	75	Stream	Sangke, Xiahe	34.9377	102.6594	3249
32	Stream	Ridang, Longzi	28.4883	92.2845	4119	76	Stream	Maai, Luqu	34.5901	102.4854	3112
33	Stream	Xuesha, Longzi	28.6346	92.5459	4245	77	Stream	Gahai, Luqu	34.4331	102.2976	3432
34	Stream	Xuesha, Longzi	28.6337	92.5489	4175	78	Stream	Gahai, Luqu	34.2006	102.4419	3491
35	Stream	Xuesha, Longzi	28.6038	92.5566	3905	79	Stream	Benzilan, Luqu	34.1269	102.6116	3358
36	Stream	Rerong, Longzi	28.4856	92.1489	4064	80	Stream	Langmu, Luqu	34.0949	102.6318	3393
37	Well (8 m)	Menbu, Nyalam	28.7857	86.2255	4452	81	Stream	Hongxing, Nuoergai	34.0959	102.7545	3161
38	Stream	Menbu, Nyalam	28.5812	86.1501	4857	82	Stream	Zhagana, Diebu	34.2394	103.1792	2974
39	Stream	Yalai, Nyalam	28.4565	86.1650	4560	83	Stream	Zhagana, Diebu	34.2374	103.2025	2978
40	Stream	Nyalam, Nyalam	28.1598	85.9805	3771	84	Stream	Zhagana, Diebu	34.2370	103.1979	2939
41	Stream	Nyalam, Nyalam	28.1634	85.9768	3788	85	Stream	Dianga, Diebu	34.0558	103.2373	2355
42	Stream	Yalai, Nyalam	28.2928	86.0248	4104	86	Stream	Wangzang, Diebu	33.9520	103.6059	2007
43	Stream	Yalai, Nyalam	28.3273	86.0474	4259	87	Stream	Huayuan, Diebu	33.9885	103.9207	1733
44	Stream	Yalai, Nyalam	28.3828	86.1070	4373	88	Stream	Sigou, Minxian	34.2426	103.9113	2948

Table 1

Figure 2

Table 2

Figure 3

Table 3

Figure 4

Figure 5

Figure 6

Table 4

Figure 7

Table 5

Figure 8

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Parameters		pH	TDS	TH	Ca²⁺	K⁺	Mg²⁺	Na⁺	HCO₃^-	Cl^-	SO₄^2-	NO₃^-	Si
Unit			mg/L	mmol/L	mg/L	mg/L	mg/L	mg/L	mg/L	mg/L	mg/L	mg/L	mg/L
All	Min	6.52	6.11	3.69	1.10	0.00	0.19	0.19	2.95	0.00	1.29	0.00	2.08
	Max	8.88	583	512	149	8.43	71.0	32.8	305	21.7	356	32.2	20.7
	Mean	7.75	180	168	44.7	1.03	13.5	6.06	127	2.33	59.2	2.60	8.77
	Median	7.75	171	143	42.3	0.87	9.02	3.75	109	0.68	28.7	1.15	7.64
	SD	0.50	130	127	30.9	1.06	14.6	6.30	95.8	3.98	80.8	4.48	4.10
	Skewness	-0.04	1.13	0.88	0.77	3.89	1.75	1.66	0.37	2.94	2.03	4.33	0.85
West	Min	6.99	32.9	27.6	9.38	0.00	0.99	0.19	16.4	0.00	3.48	0.00	4.85
	Max	8.88	391	394	69.3	8.43	52.9	32.8	302	21.7	199	32.2	20.7
	Mean	8.38	142	122	31.0	1.44	10.6	10.8	106	5.62	46.9	3.41	10.2
	Median	7.74	171	146	42.4	0.86	9.09	3.54	108	0.67	29.6	1.17	7.50
	SD	0.44	79.1	82.8	17.4	1.77	11.1	8.37	70.1	6.79	45.0	7.42	4.96
	Skewness	-1.97	1.45	1.76	0.54	3.37	2.95	0.74	0.92	1.08	2.13	3.23	0.75
South	Min	6.52	6.11	3.69	1.10	0.00	0.19	0.38	2.95	0.31	1.29	0.40	2.08
	Max	8.07	583	512	149	2.72	58.7	23.7	305	9.84	356	19.2	18.3
	Mean	7.57	187	163	44.5	0.77	12.5	4.32	98.6	0.96	74.4	1.74	8.46
	Median	7.66	131	128	38.4	0.64	5.30	3.02	74.3	0.57	38.3	1.04	6.95
	SD	0.36	156	146	36.0	0.68	15.2	4.68	90.6	1.68	95.7	2.71	4.04
	Skewness	-1.11	0.92	0.90	0.85	0.76	1.44	1.92	0.93	4.47	1.51	5.30	0.68
Northeast	Min	6.87	119	148	40.6	0.34	4.44	0.99	162	0.97	3.35	0.92	3.51
	Max	8.14	330	462	81.9	2.87	71.0	20.6	298	12.4	139	16.3	14.0
	Mean	7.66	198	231	59.9	1.40	19.5	6.50	238	3.11	24.5	4.38	8.22
	Median	7.77	198	224	58.1	1.00	17.1	4.34	250	2.54	15.7	2.09	8.04
	SD	0.40	47.7	66.8	12.0	0.76	14.4	5.48	37.2	2.58	31.2	3.96	2.64
	Skewness	-0.68	0.91	2.27	0.14	0.47	2.54	1.55	-0.28	2.70	2.90	1.59	0.34

Parameters	GB	WHO	Number of exceeding the drinking water standards
Parameters	(MH 2007)	(WHO 2008)	West	South	Northeast
pH	6.5-8.5	6.5-9.5	9 (50%)	0	0
TDS	1000	1000	0	0	0
TH	450	500	0	4 (7.5%)	1 (5.9%)
Ca²⁺	-	300	0	0	0
Mg²⁺	-	300	0	0	0
Na⁺	200	200	0	0	0
Cl^-	250	250	0	0	0
SO₄^2-	250	250	0	6 (11%)	0
NO₃^-	44	50	0	0	0

Parameter	Border area of QT			GB	WHO
Parameter	Western	Southern	Northeastern	(MH 2007)	(WHO 2008)
NO₂^- (mg/L)	n.a.	0.02	0.08	-	3
NO₃^- (mg/L)	3.41	1.71	4.38	44	50
SO₄^2- (mg/L)	46.91	74.45	24.53	250	250
PO₄^3- (mg/L)	n.a.	n.a.	n.a.	-	-

No.	West		South		Northeast
No.	Eigenvalue	% of variance	Eigenvalue	% of variance	Eigenvalue	% of variance
1	7.3178	52.2703	6.9330	49.5215	6.9762	49.8304
2	3.4631	24.7362	2.1551	15.3934	2.3914	17.0814
3	1.1666	8.3326	1.4682	10.4873	1.9171	13.6934
4	0.6698	4.7843	0.9467	6.7622	1.1243	8.0310
5	0.4954	3.5387	0.7184	5.1313	0.7262	5.1872
6	0.3340	2.3859	0.7059	5.0418	0.5176	3.6968
7	0.2622	1.8729	0.4028	2.8774	0.1330	0.9501
8	0.1449	1.0349	0.3045	2.1753	0.1023	0.7308
9	0.1013	0.7236	0.2039	1.4561	0.0677	0.4835
10	0.0368	0.2627	0.0923	0.6594	0.0241	0.1724
11	0.0076	0.0542	0.0662	0.4728	0.0196	0.1397
12	0.0005	0.0037	0.0019	0.0135	0.0005	0.0034
13	0.0000	0.0000	0.0011	0.0079	0.0000	0.0000
14	0.0000	0.0000	0.0000	0.0000	0.0000	0.0000