Hindawi Publishing Corporation e Scientific World Journal Volume 2014, Article ID 183457, 10 pages http://dx.doi.org/10.1155/2014/183457 Research Article Impacts of Groundwater Recharge from Rubber Dams on the Hydrogeological Environment in Luoyang Basin, China Shaogang Dong,1 Baiwei Liu,2 Huamin Liu,3 Shidong Wang,4 and Lixin Wang1 1 College of Environment and Resources, Inner Mongolia University, Hohhot 010021, China 2 School of Environmental Studies, China University of Geosciences, Wuhan 430074, China 3 CollegeofLifeSciences,InnerMongoliaUniversity,Hohhot010021,China 4 National Secondary Occupation School, Xilingol Vocational College, Xilinhot 026000, China Correspondence should be addressed to Huamin Liu; [email protected] and Lixin Wang; [email protected] Received 9 June 2014; Revised 21 June 2014; Accepted 21 June 2014; Published 14 July 2014 Academic Editor: Hongbo Shao Copyright © 2014 Shaogang Dong et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. In the rubber dam’s impact area, the groundwater total hardness (TH) has declined since 2000, ultimately dropping to 100–300 mg/L in 2012. pH levels have shown no obvious changes. NH4-N concentration in the groundwater remained stable from 2000 to 2006, but it increased from 2007 to 2012, with the largest increase up to 0.2 mg/L. NO3-N concentration in the groundwater generally declined in 2000–2006 and then increased from 2007; the largest increase was to 10 mg/L in 2012. Total dissolved solids (TDS) of the groundwater showed a general trend of decline from 2000 to 2009, but levels increased after 2010, especially along the south bank of the Luohe River where the largest increase recorded was approximately 100 mg/L. This study has shown that the increases in the concentrations of NH4-N and NO3-N were probably caused by changes in groundwater levels. Nitrates adsorbed by the silt clay of aeration zone appear to have entered the groundwater through physical and chemical reactions. TDS increased because of groundwater evaporation and some soluble ions entered the groundwater in the unsaturated zone. The distance of the contaminant to the surface of the aquifer became shorter due to the shallow depth of groundwater, resulting in the observed rise in pollutant concentrations more pronounced. 1. Introduction over fertilization in agriculture [2–4]. Insecticide residue polluted the surface water and shallow groundwater [5, 6]. Groundwater is an important water resource because of its Solid municipal waste and industrially manufactured solid wide distribution, good quality, ease of access, and small sea- waste increased the organic, heavy metals, and inorganic sonal shifts. It becomes critical especially in arid and semiarid groundwater ions [7–9]. Excess discharge of domestic and areas,asitmayoftenbetheonlywatersource.Thechemical industrial wastewater has also polluted the groundwater compositions of the natural groundwater developed during [10]. Groundwater overpumping in coastal areas has caused the long geological history. It is affected by the types and seawater intrusion [11–13]. characters of rocks to which the water is exposed, the feature Since 1965, more than 1000 rubber dams have been built of the replenishment water, and the water-rock interactions. in China for various purposes, such as irrigation, hydropow- As human actions on the environment have intensified, they er, groundwater replenishment, flood control, beautification have become a primary cause of the impact on the chemical of the environment, and recreation [14]. There are still a characteristics of the groundwater in certain locations. For certainnumberofrubberdamsunderconstructionandbeing example, groundwater has been overpumped for industrial planned, especially in the arid and semiarid parts of China. use and agriculture, which has caused the groundwater levels The construction of rubber dams has changed the character- to decline and quality to deteriorate [1]. The concentration istics of the regional groundwater flow system and increased of nitrogen of the regional groundwater was raised by the amount of groundwater. It has also caused a series of 2 The Scientific World Journal 112 00 112 30 113 00 113 20 Qinhe River 35 Baiqiang reservoir 35 00 Yellow River 00 Wen county Mengzhou city Mangshan mountain Yanshi city Xiaoshan mountain Gongyi city Luoyang cityLuohe River Yihe River Plain area of Luoyang basin 34 Luohe River 34 Songshan mountain 30 Yiyang county 30 Xionger mountain Dengfeng city 34 Yihe River Basha reservoir 34 15 112 30 113 00 15 Figure 1: Luoyang Basin map. environmental problems. The rise in the groundwater table and occurrence regulations of groundwater were dominated has increased groundwater evaporation capacity, caused soil primarily by meteorology, hydrology, topography, formation salinization, and increased groundwater salinity [15]. lithology, and geological structure. Precipitation infiltration The groundwater recharge quantity of Luoyang Basin is is the main supplement to groundwater. 8 3 3.3–4.1 × 10 m /a (from 1995 to 1999) and the exploitation The south side of the Basin is wildly composed, with 8 3 quantity is 3.8–4.3 × 10 m /a (from 1996 to 2000). The sub- carbonaterocks,andthenorthandwestsidearealoesshilly stantial decline in groundwater levels and the deterioration area with a steep slope and developed a deep clough. This kind in quality were due to annual local overexploitation. In order of landform lends itself easily to runoff and discharge. The to meet needs for groundwater as a resource and beautify the groundwater in this area can run very short. urban environment, five rubber dams were built on the Luohe The Yi-luohe River alluvial plain has subsided since the River from 2000 to 2008. This paper discusses the impact of Quaternary period. It was the lowest part of this area and the rubber dam construction on groundwater and provides became a catchment area for surface water and groundwater. references for groundwater environment management and The aquifer of the whole Yi-luohe River alluvial plain area, protection of Luoyang Basin. especially in the massif and overbank, is thick. The aquifer is either directly exposed to the surface or covered by a minimal layer of earth or rock. This area has abundant groundwater 3 2. Regional Physical Geography resources. Generally, a single well can yield over 3000 m /d. and Hydrogeology The first and second terraces are mostly presented with a dual structure, an upper layer covered with sandy clay, and a lower 2.1. Regional Physical Geography. The Luoyang Basin is layer stock with coarse sand and sandy gravel. Here, a single 3 located in western Henan Province, surrounded by Mang well can yield 1000–3000 m /d (Figure 2). Shan, Xiao Shan, Xionger Shan, and Song Shan (Figure 1). It has a warm-temperate and monsoon climate. According to meteorological data, the perennial average temperature is ∘ 3. Primary Environmental 14.3 C and multiyear evaporation is 1451.7 mm. The multiyear average precipitation is 545.98 mm and this is subject to Geological Problems before and after considerable temporal and spatial change. Precipitation is the Rubber Dam Construction concentrated in July, August, and September, accounting for From 1957 to present, there have been thirteen groundwater about 50% of annual precipitation. source fields found in the Luoyang Basin, the total yield 3 reached 280–300 million m /a. According to the monitoring 2.2. Regional Hydrogeology. The Luoyang Basin formed in data, the groundwater depth of the Luohe Riverside was the late Mesozoic. It is a complete hydrogeological unit, 5.9–11.5 m in the middle and late 1980s. Because of overex- surrounded by mountainous and loess hills. The Yi-luohe ploitation, the groundwater table has declined since the early River alluvial plain is in the middle of it. Distribution 1990s. The Luohe River became a suspended river. Until 1999, The Scientific World Journal 3 Mangshan mountain (km) 05 A Yanshi city Lk5 Luohe River Jianhe River Luoyang city 2008 Lk6 Yihe River 2005 2002 Lk7 2001 Lk4 Lk11 Lk8 2000 B B Lk3 Lk14 A Songshan mountain (I) Loose rock pore water (II) Karst water Water sources area Aquifer of higher transmissivity Exposed karst water area Rubber dam and impounding time 3 2000 (water out flow from single well > 3000 m /d) Aquifer of medium transmissivity Covered karst water area River flow direction 3 (water out flow from single well 1000–3000 m /d) Aquifer of low transmissivity (III) Fissure water Ground water flow direction 100 1000 3 (water out flow from single well – m /d) (km) Aquifer of very low transmissivity Exposed fissure water area 05 3 (water out flow from single well <100m /d) Covered fissure water area Yidong ditch Lk8 Yihe River Lk7 Lk6 Luohe River Lk5 A A Q4 150 100 Q3 Q3 50 0 Q1 Q2 Elevation −50 184 m −100 201 Q1 m 207 m 239 m C-P Lk8 Luohe River Lk14 Lk4 Yihe River Lk3 Lk11 B B Q4 150 100 Q3 50 Q Q 0 120 m 1 2 Elevation −50 Q 1 200 m −100 195 m 201 m 225 m Lk8 Sandy clay Silty gravel Drill number and depth 184 Silty clay Clay Fault Pebble Carboniferous-permian shale Gravel Stratum boundary Geological profiles A-A and B-B in the study area Figure 2: Hydrogeological plan fig. and profiles A–A and B–B in the Luoyang Basin. 4 The Scientific World Journal A N8 Jianhe River Luohe River 150 2010 A B7 S1 2004 Luohe Z4 Z2 River level Ln2 Ln7 B3 B8 140 B1B2 C B4 B9 S2 Yihe River 1980 C B5 130 B6 1990 Elevation (m) Elevation 120 1999 Longmen (km) 110 0 10 100 CC Section lines Ground water level rise >4m Soil sampling point Sandy clay After rubber dams impounding Ground water level rise 1–4 m Water sampling point Pebble and gravel Before rubber dams impounding Ground water level rise <1m Rubber dam (a) (b) Figure 3: Changes of water tables before and after the rubber dam’s construction.