干旱区生态环境知识资源中心(Arid): Saline groundwater in the Buffels River catchment, Namaqualand, South Africa: A new look at an old problem

Arid

DOI	10.1016/j.scitotenv.2020.143140
	Saline groundwater in the Buffels River catchment, Namaqualand, South Africa: A new look at an old problem
	van Gend, J.; Francis, M. L.; Watson, A. P.; Palcsu, L.; Horvath, A.; Macey, P. H.; le Roux, P.; Clarke, C. E.; Miller, J. A.
通讯作者	Miller, JA (corresponding author), Stellenbosch Univ, Dept Earth Sci, Private Bag X1, Matieland, South Africa.
来源期刊	SCIENCE OF THE TOTAL ENVIRONMENT
ISSN	0048-9697
EISSN	1879-1026
出版年	2021
卷号	762
英文摘要	Namaqualand, South Africa, is a global biodiversity hotspot but local populations are affected by challenging economic conditions largely because of poor access to water. In this study groundwater types are characterised and sources of salts and salinisation processes are identified using hydrochemistry and delta O-18, delta H-2 and Sr-87/Sr-86 data. Analysis of delta O-18 and delta H-2 data suggests that evaporation does not play a major role in salinisation of the groundwater. However, major ion chemistry and Sr-87/Sr-86 ratios indicate that salts present in the groundwater are linked to dry deposition of marine aerosols and ion-exchange reactions in soils in the alluvial aquifer systems. The hydrochemical variability of the groundwater in the basement aquifer system suggests that there are strong local controls linked to weathering processes in individual basement rock types. The region is also notable for the high density of heuweltjies, biophysical features associated with increased nutrient levels, associated with termite activity. Electromagnetic scanning as well as measurement of water-soluble soil electrical conductivity values on and off heuweltjies, show that heuweltjies are saline with salinity increasing with depth. The level of groundwater salinity correlates with the level of heuweltjie salinity. Precipitation records from the last 150 years provide support for the hypothesis that accumulated salts, and in particular, heuweltjie salts are flushed into the groundwater system during sporadic large volume precipitation events. Thus, heuweltjies and hence termite activity, could potentially represent a previously unrecognized contributor to groundwater salinisation across Namaqualand and in other parts of the world. (C) 2020 Elsevier B.V. All rights reserved.
英文关键词	Natural groundwater salinity Heuweltjies Arid environments Hydrochemistry Environmental isotopes
类型	Article
语种	英语
收录类别	SCI-E
WOS记录号	WOS:000607910300071
WOS关键词	EARTH MOUNDS ; MICROHODOTERMES-VIATOR ; SOIL-SALINITY ; CAPE-PROVINCE ; LAND-USE ; METAMORPHIC PROVINCE ; SEAWATER INTRUSION ; HARVESTER TERMITE ; ARID ENVIRONMENT ; COASTAL-AQUIFER
WOS类目	Environmental Sciences
WOS研究方向	Environmental Sciences & Ecology
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/348168
作者单位	[van Gend, J.; Watson, A. P.; Miller, J. A.] Stellenbosch Univ, Dept Earth Sci, Private Bag X1, Matieland, South Africa; [Francis, M. L.; Clarke, C. E.] Stellenbosch Univ, Dept Soil Sci, Private Bag X1, Matieland, South Africa; [Palcsu, L.; Horvath, A.] Isotope Climatol & Environm Res Ctr, Debrecen, Hungary; [Macey, P. H.] Council Geosci, POB 572, ZA-7530 Bellville, South Africa; [le Roux, P.] Univ Cape Town, Dept Geol Sci, Cape Town, South Africa
推荐引用方式 GB/T 7714	van Gend, J.,Francis, M. L.,Watson, A. P.,et al. Saline groundwater in the Buffels River catchment, Namaqualand, South Africa: A new look at an old problem[J],2021,762.
APA	van Gend, J..,Francis, M. L..,Watson, A. P..,Palcsu, L..,Horvath, A..,...&Miller, J. A..(2021).Saline groundwater in the Buffels River catchment, Namaqualand, South Africa: A new look at an old problem.SCIENCE OF THE TOTAL ENVIRONMENT,762.
MLA	van Gend, J.,et al."Saline groundwater in the Buffels River catchment, Namaqualand, South Africa: A new look at an old problem".SCIENCE OF THE TOTAL ENVIRONMENT 762(2021).