Relationship between Water and Vegetation in the Ejina Dclta

Vol.26 No.12012 Agriculture Water & EcologyEjina aquifer was recharged by multi-sources by usingspatial distributions of the hydrochemical compositionshydrochemical and environmental isotopes tracer technique,that exist in shallow groundwater of the downstreamand the surface water from Heihe River was the mainalong the both sides of the Heihe River (10 km). According to this study, the groundw aterof the shallow groundwater in the lower Heihe River is alsorecharge zones by river water were preliminary identifiedinfluenced by groundwater recharge from Badain Jaran(Wen, et al., 2005). There are also many scientists whodesert, adjacent basins, as well as lateral groundwater inflowuse environmental isotope technique, together withfrom the adjacent mountains (Wu, et al, 2002; Qian, ethydrochemical analysis, to study the impact of theal, 2005). Although groundwater in the Ejina aquifer has aenv ironmental flow controls on the shallow groundwaterdiversity of supply sources, the infiltration of surface waterenvironment as well as its evolution (Chen, et al.,from the Heihe River still is the main shallow groundwater2006; Su, et al, 2009; Zhu, et al, 2010), then inferredrecharge source, and is the key factor which maintains thethe relationship of water transformation between theecological environment in this region.groundwater and the river water. In relation to the impactThus, in recent years, researchers have graduallyof the volume and duration of runoff on water tablefocused their attention on the mechanism behind surface-changes, there are some scientists who with the help ofgroundwater interaction, which controls the groundwaterlinear regression methods to determine the relationshiplevel and salinity dynamics. Since 2000, Chinesebetween shallow groundwater table and total runoffscientists have used geophysical exploration, penetration(Li, et al, 2006; Hu & Song, 2007). However, furthertests and other methods to identify the interactioncomprehensive investigations are needed to fully quantifybetween the shallow groundwater and the surface waterthe groundwater recharge areas, as well as its temporal-in the lower Heihe River. Their results indicate that therespatial variations under the human controlled conditions,exists a fault zone in the Dingxin-Shaomaying valley,and also to identify the infuence of riverbed cross-sectionand lots of surface water from the Heihe River rechargesform and hydraulic conductivity of riverbed and aquiferthe shallow aquifer though thus fault zone (Wu, et al.,on transformation of water flux and salinity between2000, 2004). Besides, some researchers analyzed thesurface water and groundwater.2. The threshold of groundwater depth and salinity of natural vegetationOne of the key ecological factors in arid areas, thedevelopment, as ecological warning groundwater depth,groundwater table controls the changes and compositionand more than 6m as desertification groundwater depth (Fanof plant communities, and has a significant impact onet al., 2004). Satellite remote sensing decipherment andcomposition, development and stability of an inland rivergroundwater dynamics analysis in the lower reaches of thebasin ecosystem in arid areas (Ma & Gao, 1997). ManyHeihe River showed that the suitable groundwater depthstudies had confirmed that soil moisture and salinityof typical vegetation growth in Ejina Delta is 2-5m (Wang,influenced the growth and restoration of natural vegetationet al, 2011b; Jin, 2010). Quantitative classification andand was closely related to groundwater depth (Liu, 1996;analysis of relationships between plant communities andMa, 1997; Liu, 1984). In a sense, groundwater depththeir groundwater environment in the Ejina oasis indicatedetermines the distribution, growth, population successionthat increasing groundwater depth, due to groundwaterof natural vegetation in arid areas, and even the survivalenvironmental degradation such as groundwater salinityof the whole oasis. According to the relationships betweenincrease, is the main reason causing changes in communitygroundwater table and vegetation dynamic changes, ourdistribution and type in the region (Zhu et al., 2011a).researchers defined the groundwater depth within 1m asZhu et al. (2011b) performed two-wav indicator speciesthe swamping groundwater depth, 1-2m as salinizationanalysis (TWI中国煤化工getation types ingroundwater depth, 2-4m as proper ecological groundwater31 plant plots! YHCNMHGgtheresultsofdepth, 4-6m, which produces stress on plant growth andthe TWINSPAN classfication with practical ecologicalBulletin of the Chinese Academy of Sciences 71.中国煤化工YHCNMH G中国煤化工YHCNMH G中国煤化工YHCNMH GVol.26 No.1 2012 Agriculture water & EcologyDavis, J. et al. 2003. What happens when you add salt: predicting impacts of secondary salinisatin on shallow aquatic ecosystems by using anatternative- states model. Australian Jourmal of Botany :51 (6), 715-724.Duwala, et al, 2008. Remote sensing monitoring on vegetation restoration of Ejina oasis after Heihe river's water diversion. Arid Meteorology. (04), 67-70 (in Chinese).Fan, Z L et al, 2004. Research of eco-water table and rational depth of groundwater of Tarm River drainage basin. Anid Land Geography: (01), 8-13 (in Chinese).Froend, R. et al, 1987. Efects of salinity and waterlogging on the vegetation of Lake Toolibin, Westerm Austraia. Australian Joumal of Ecology.12 (3). 281- -298.nGuo, Q. L et al,. 2009. Environmental changes atter ecological water conveyance in the lower reaches of Heihe River, northwest China. EnvironmentalGeology: 58 (7), 1387-1396.Hu, J. H., & Song, H. x.2007. Relationship between surface water and groundwater in Ejina Oasis. Yellow River. (12), 51- -52 (in Chinese).Institute of Earth Sciences, Chinese Academy of Sciences, 1996. Water resources investigation report of northwestern arid region-proposals aboutreasonable use of water and repiring ecology in Heihe River Basin and Shiyang River Basin.Advance in Earth Sciences.11 (1), 1-4 (in Chinese).Jin, x. M. et al., 2010. Quantitative relationship between the desert vegetation and groundwater depth in Ejina Oasis, the Heihe River Basin. EarthScience Frontiers: (06). 181-186 (in Chinese).Leng, s. Y., & Song, C. Q, 2010. Progress in the researches on the Earth Surface process in West China under the supports by National NaturalScience Foundation of China. Progress in Geogrephy: (02), 9-13 (in Chinese).Li, Q. K. et al, 2006. Study on the ecological water requirements for restoring the oasis in Ejina region. Jourma/ of Water Resources & WaterEngineering: 17(2), 9-13 (in Chinese).Liu, c. M. 1996. Soil salinity control regarding subsurface water regulation in north china plain. The Joumal of Chinese Geography: 6(4). 28 -37.Liu, Y. C. et al, 1984. Discussion on hydrogeological environment and osis ecological agriculture. Hydrogeology and Engineering Geology: (06), 28-30(in Chinese).Ma, J. Z.1997. Sustainable exploitation and uilization of water resources in the inland river basin of arid Northwest China. Chinese GeographicalScience: 7 (4), 347- -351.Ma,J.Z .. & Gao, Q. z.. 1997. Water resources system and eco-environmental problems in the inland river basin of arid Nothwest China. Joumal/ ofAnd Land Resources and Enironmet11(04) , 15-21 (in Chinese).Qian, Y. P. et al. 2005. Study on groundwater of the Eina Basin at the lower reaches of the HeiheRiver using istopes. Arid Land Geography.28 (5),574-580 (in Chinese),Su, Y. H. et al, 2009. Environmental isotopic and hydrochemical study of groundwater in the Ejina Basin, northwest China. Environmental Geology. 58(3), 601-614.g, M. L. et al..2001. Significance of groundwater for existence and succession of vegetation in Northwest China. Geological Science andTang,M.Technology Iformation (02) , 79-82 (in Chinese).Wang, P. et al, 2011a. Impacts of environmental flow controls on the water table and groundwater chemistry in the Ejina Delta, northwestern China.Environmental Earth Sciences: 64, 15- -24.Wang, P. et al.2011b. Vegetation dynamics induced by groundwater fluctuations in the lower Heihe River Basin, northwestern China. Journal of PlantEcology:4(1- 2), 77-90.Wen, x. et el.2005. Hydrochemical characteristics and salinity of groundwater in the Eina Basin, Northwestem China. Environmental Geology:48 (6), 665 -675.Wu, X. M. et al, 2002. The study on the groundwater flow system of Ejina Basin in lower reaches of the Heihe River in Northwest China. Hydrogeologyand Engineering Geology: (01) .16- -20 (in Chinese).Wu, Y. Q. et al..2000. Analysis of the transformation path between stream flow and groundwater from Dingxin to Shaomaying in Heihe River, catchmentWest China. Journal of Glaciology and Geocryologys: 22(01), 73-77 (in Chinese).Wu, Y. Q. et a/. 2004. New findings about interaction between river water and groundwater in the lower reach of Heihe River Basin, Northwest China.Progress in Natural Science:14 (12), 1428-1433 (in Chinese)Xue, z. Q. et al. 2006. Analyses of variations of the Ejina Oasis and relevant factors in the downstream of the Heihe River, Northwest China. EarthScience Frontiers: (1), 48-51 (n Chinese).Zhang, G. H. ot al., 2005. lsotopic characteristic and recharge fect of groundwater in the water circulation of Heihe River Basin. Advance in EarthSciences:20 (5). 511- -519 (in Chinese).Zhang, L. et al.. 2002. Natural stand and its water requirement in lower reach of Heihe River. Irigation and Drainage: (04), 16- -20 (in Chinese).Zhang, L. et al..2004. Modeling on relatin between major plants growth and groundwater depth in arid area. Journal of Desert Research:24(01). 110-113 (in Chinese).Zhang, Y. C. et al, 2011a. Vegetation responses to integrated water management in the Ejina Basin, northwest China. Hydrological Processes: 25(22),3448-3461Zhang,Y. C. et al, 2011b. Effects of eco-water transfer on changes of vegetation in the lower Heihe River Basin. Jourmal of Hydraulic Engineering:42(07), 757-765 (in Chinese).Zhao, W. z.. & Cheng, G. D.2001. Review of eco-hydrologicai processes research in arid region. Chinese Science Bulletin: (22), 1851-1857 (in Chinese),Zhong, H. P. et al, 2002. Relationship between Ejina Oasis and water resources in the lower Heihe River Basin. Advances in Water Science:28 (5) ,574-580 (in Chines).Zhou, A. G. et al.. 2004. Geoecology of the Ejina Basin in North-Westem Arid Region, P.R.China China University of Geosciences Wuhan (in Chinese).Zhu, G. F. et al/, 2010. Hydrogeochemical processes in the groundwater environment of Heihe River Basin, northwest China. Environmental EarthZhu, J. T. et al., 2011a. Quantitative cassication and analysis of relationships between plant commSciences: 60 (1), 139-153.中国煤化工。onment in theEjin Desert Oasis of China. Chinese Joumal of Plant Ecology: 35(5), 480 489 (n Chinese).Y出.CNMH GZhu, J. T. et al, 2011b. Interpreting the groundwater atributes infuencing the distribution patterns of grounawater-aepenaent vegetaon in northwestermChina, Ecohydrology (online). DOI: 10.1002/eco.249.Bulletin of the Chinese Academy of Sciences 75.