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Desert riparian vegetation and groundwater in the lower reaches of the Tarim River basin 总被引：1，自引：0，他引：1
Yaning Chen Weihong Li Changchun Xu Zhaoxia Ye Yapeng Chen 《Environmental Earth Sciences》2015,73(2):547-558
The Green Corridor in the lower reaches of Tarim River in northwestern China has an extreme hot and dry climate. Vegetation here, consisting of arbor, shrub and grass, relies on groundwater exceedingly. However, the increasing anthropogenic activities of large-scale agricultural reclamation and unreasonable water utilization in the upper and middle reaches caused the 321-km riverway in the lower reaches to dry up completely in 1972 and resulted in the sharp decline of groundwater, followed by the ruin of desert riparian vegetation on a large scale. The Green Corridor is on the verge of shrinking. Water has a key role in maintaining ecological balance and socioeconomic development. This paper, focused on the relationship between vegetation and groundwater, discusses (1) the change of groundwater table caused by the ecological water delivery carried out in the lower reaches of Tarim River; (2) the appropriate groundwater depth meeting the vegetation’s survival; (3) the minimum ecological flux and ecological water requirement for the growth of natural vegetation. It was shown that (1) based on the analysis of the monitoring data from the groundwater level of ten times water delivery, such an extensive artificial watering takes positive effect on raising the groundwater level along the two sides of the river; (2) a groundwater table depth of 2–4 m is probably the appropriate ecological water table level for the lower reaches of the Tarim River, and 6 m is the threshold for the local vegetation; (3) at the lower Tarim River, 1.157 × 108 m3 of water flow is needed for itself. The longer the duration of water releases, the greater would be the groundwater rise and the larger the range of vegetation influenced. It was found that the duration and volume of water delivery was closely related to restoration of vegetation in the lower reaches of the Tarim River. The goal of this paper is to offer scientific evidences for water delivery in the rigorous areas to maintain an ecological balance. 相似文献
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银川平原植被生长与地下水关系研究 总被引：15，自引：1，他引：14
干旱区植被生长与地下水的关系是生态水文地质学研究的热点之一。西北内陆干旱地区降水稀少,植被的生长发育与地下水的关系极为密切,从大尺度上研究地下水变化的生态效应问题对生态环境的保护和恢复具有重要的意义。借助遥感方法,结合地下水观测数据,在区域尺度上定量地研究了中国银川平原地区地下水埋深及矿化度与植被生长的关系。结果表明:适宜植被生长的地下水埋深范围约为1~6m,当地下水位埋深为3.5m左右时,植被长势最好。而在水位埋深为3.5m左右的地区,植被生长的相对好坏又受地下水矿化度的影响。当地下水矿化度为0.9g/L时对该地区植被的生长最为有利。 相似文献
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Comprehensive evaluation on the ecological function of groundwater in the Shiyang River watershed 
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下载免费PDF全文 Liu Min Nie Zhen-long Cao Le Wang Li-fang Lu Hui-xiong Wang Zhe Zhu Pu-cheng 《地下水科学与工程》2021,9(4):326-340
With an arid climate and shortage of water resources, the groundwater dependent ecosystems in the oasis–desert ecotone of the Shiyang River Watershed has been extremely damaged, and the water crisis in the oasis has become a major concern in the social and the scientific community. In this study, the degeneration characteristics of the groundwater ecological function was identified and comprehensive evaluated, based on groundwater depth data, vegetation quadrat and normalized difference vegetation index (NDVI) from Landsat program. The results showed that (1) the suitable groundwater depth for sustainable ecology in the Shiyang River Watershed is about 2-4 m; (2) the terms of degenerative, qualitative and disastrous stages of the groundwater ecological function are defined with the groundwater depths of about 5 m, 7 m and 10 m; (3) generally, the groundwater ecological function in the oasis-desert ecotone of the lower reaches of Shiyang River Watershed is weak with an area of 1 397.9 km2 identified as the severe deterioration region, which accounted 74.7% of the total area. In the meantime, the percentages of the good, mild and moderate deterioration areas of groundwater ecological function are 3.5%, 5.5% and 16.3%, respectively, which were mainly distributed in the Qingtu lake area and the southeastern area of the Shoucheng town; (4) the degradation and shrinkage of natural oasis could be attributed to the dramatic groundwater decline, which is generally caused by irrational use of water and soil resources. This study could provide theoretical basis and scientific support for the decision-making in environmental management and ecological restoration of the Shiyang River Watershed. 相似文献
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生态植被的地下水阈值是指植被依赖地下水生长的最大水位埋深和溶解性总固体含量（TDS）。控制地下水开采生态风险的基础是弄清生态植被与地下水的依存关系并给出地下水阈值。文章利用遥感数据集MOD13Q1和水文地质调查获得的实测数据,统计分析了柴达木盆地主要平原区生态植被与潜水的水位埋深、TDS的关系。结果表明:天然植被依赖地下水的阈值是水位埋深为5.3 m、TDS为7.5 g/L;埋深＞5.3 m地带的天然植被基本与地下水无关;埋深＜1.1 m是水生植被、湿生植被与湿生耐盐碱植被适宜生长的水位埋深区间;埋深1.4~3.5 m是耐盐植被及中生植被与旱生植被适合生长的水位埋深区间;TDS≤1.5 g/L适宜植被生长,1.5 g/L＜TDS≤5 g/L较适宜植被生长,5 g/L＜TDS≤7.5 g/L基本不适宜植被生长,TDS＞7.5 g/L不适宜植被生长。 相似文献
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海流兔河流域植被分布与地形地貌及地下水位关系研究 总被引：1，自引：0，他引：1
干旱区植被与地形地貌及地下水的相互依存关系是揭示植被生态水文过程的关键。由于降水稀少,中国西北地区植被的生长发育与地貌和地下水的关系极为密切,从大尺度上研究地形地貌和地下水变化的生态效应问题对生态环境的保护和恢复具有重要的意义。应用遥感方法,基于地形地貌和地下水位观测数据,在流域尺度上定量地研究了中国鄂尔多斯高原海流兔河流域植被发育与地形地貌和地下水埋深的关系。结果表明：河谷、滩地、沙丘、沙地地貌的植被发育状况是依次变差的,植被在高程1 220 m左右处发育最好。地下水位埋深对植被的影响范围为1~5 m,当地下水位埋深超过5 m时,气候与土壤因素是决定植被的主要因素,地下水位的变化对植被的长生状况影响不大。 相似文献
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To accurately evaluate ecological risks trigged by groundwater exploitation, it must be clarified the relationship between vegetation and groundwater. Based on remote sensing data sets MOD13Q1, groundwater table depth (WTD) and total dissolved solids (TDS), the relationship between groundwater and natural vegetation was analyzed statistically in the main plain areas of Qaidam Basin. The results indicate that natural vegetation is groundwater-dependent in areas where WTD is less than 5.5 m and TDS is less than 7.5 g/L. Aquatic vegetation, hygrophytic vegetation and hygrophytic saline-alkali tolerant vegetation are mainly distributed in areas with WTD <1.1 m. Salt-tolerant and mesophytic vegetation mainly occur in areas with WTD of 1.4-3.5 m, while the xerophytic vegetation isprimarily present in areas where WTD ranges from 1.4 m to 5.5 m. Natural vegetation does not necessarily depend on groundwater in areas with WTD >5.5 m. For natural vegetation, the most suitable water TDS is less than 1.5 g/L, the moderately suitable TDS is 1.5-5.0 g/L, the basically suitable TDS is 5.0-7.5 g/L, and the unsuitable TDS is more than 7.5 g/L. 相似文献
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甘肃石羊河流域民勤盆地水资源短缺,生态环境脆弱,弄清地下水埋深与天然生态植被生长的关系,是精准调控地下水开采、针对性制定生态保护政策的重要理论依据。利用民勤盆地2000—2017年LANDSAT遥感数据,计算归一化差值植被指数（NDVI）年均值,结合85眼监测井的地下水埋深实测数据,分析了植被生长与埋深的关系。结果显示:研究区植被NDVI较低,多年均值约0.1,2012年后NDVI趋于增大,反映人工造林等措施成果明显。地下水埋深总体趋于增大,2008年后增幅减缓,目前埋深西部大于20 m,东部、北部小于20 m。区内适宜植被生长的埋深范围为2.5~3.9 m,多年平均适宜生态水位约2.66 m;埋深小于4 m时,NDVI与埋深表现为高度负相关(R<-0.8),即埋深越小,NDVI越高;埋深大于4 m时,两者无明显关系。较前人成果,文章从长序列时间、盆地空间尺度分析了民勤绿洲区天然植被生长与地下水埋深的变化,得到浅埋区生态水位,进而圈定了生态治理重点靶区。 相似文献
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西北内陆流域下游区天然植被对地下水生态功能具有强烈依赖性,而包气带岩性结构对地下水生态功能具有明显影响,但是在目前的研究中,缺乏定量分析评判。以甘肃石羊河流域下游天然绿洲区为研究区,基于包气带岩性结构野外调查、室内土柱试验和Hydrus1-D数值模拟,研究包气带岩性结构与地下水耦合作用的生态效应,分析不同岩性结构包气带... 相似文献
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在气候变化、生态保护以及水资源调控影响下,西北内陆河流域水循环和生态环境状态发生了显著改变,迫切需要解答气候变化对植被恢复和产水量的影响,调水和压采等措施下地下水水位动态、管控指标及其对生态环境的维持机制。为此,文章阐述了内陆河流域气候-植被-土壤-水文相互作用机理以及上中下游演变状况。针对上游产水区,提出了山区气候变... 相似文献
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黑河下游额济纳绿洲荒漠植被与地下水位埋深的
定量关系 总被引：3，自引：1，他引：2
干旱区植被生长与地下水的依存关系是生态水文地质学研究的热点之一。由于降水稀少,中国西北地区植被的生长发育与地下水的关系极为密切,从大尺度上研究地下水变化的生态效应问题对生态环境的保护和恢复具有重要的意义。借助遥感方法,结合地下水观测数据,在区域尺度上定量地研究了我国黑河下游额济纳绿洲荒漠植被发育与地下水埋深的关系。结果表明:适宜植被生长的地下水埋深范围约为2~5 m,当地下水埋深超过5.5 m时,由于植被根系缺水,不能维持冠层正常生长,几乎没有植被发育。 相似文献
12.
柴达木盆地格尔木河流域生态需水量初步估算探讨 总被引：9，自引：1，他引：8
格尔木河流域是柴达木盆地工农业较发达地区之一。近年来,随着流域水资源开发利用程度不断加大,用水结构欠合理,生态环境趋于恶化。本文从流域主要植物生长状态分析了地下水位埋深对植物生长的影响,确定了不同植物对地下水位埋深、地层岩性和不同盖度下的植物蒸发蒸腾强度。从研究流域生态需水量出发,分别对河道内、河道外天然植被和东达布逊湖生态需水量进行了初步估算,分析了水资源开发利用对生态环境的影响,从而为今后研究流域水资源开发利用和生态环境保护提供理论参考。 相似文献
13.
许多地区地下水是生态稳定的重要支撑或补充,确定地下水补给地表植被的临界埋深对地下水管理和生态安全至关重要。以西辽河平原为例,主要研究成果如下:①根据地下水补给植被原理划分包气带水分运动结构,描述地下水补给植被的作用机理和物理过程,定义地下水补给植被的临界埋深及相关物理概念。②根据植被根系吸收潜水蒸发的物理机制,地下水面附近由毛管水上升形成的潜水影响层是临界埋深计算的关键。③推导土壤毛管有效孔径计算推理公式,通过构建土壤微结构模型求解推理公式中的孔隙特征参数,解决毛管水最大上升高度的精确计算难题;④结合不同群落植被根系层厚度,形成地下水补给植被的临界埋深计算模型。⑤通过野外调查和观测试验实证,表明计算结果可靠,研究成果在科尔沁草原得到了及时应用。 相似文献
14.
In Dakhla oasis, Western Desert of Egypt, groundwater is the only resource for all anthropogenic activities. During the last 50 years, the Nubian Sandstone Aquifer System (NSAS) has been undergoing serious stress through withdrawing its storage. Plans for expanding the agricultural areas in Dakhla oasis were given by the government. This article is an attempt to investigate the best management option that meets development ambitions and groundwater availability. Based on a calibrated regional three-dimensional groundwater flow model for the NSAS using FEFLOW, a refined (high resolution) local scale model was developed to simulate and predict the impact of applying the actual and planned extractions rates on Dakhla oasis. Five management scenarios were suggested. The application of the actual extraction rate of 1.2 × 106 m3/day for the oasis for the next 90 years resulted in a drawdown of 75 m and a depth to groundwater up to 75 m with an annual change in hydraulic head of 0.57 m. At the end of this simulation, only a few wells at the west of the oasis will still be free flowing. The application of the planned extraction rate (1.7 × 106 m3/day) resulted in great depths to groundwater (>100 m) and formed huge cones of depressions that connected together to cover the whole oasis and extend further beyond its borders. It was found that the best option for groundwater management in the oasis is the implementation of an extraction rate of 1.46 × 106 m3/day, as the depths to groundwater will never exceed the 100 m limit. 相似文献
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The influence of water conveyances on restoration of vegetation to the lower reaches of Tarim River 总被引：2，自引：1，他引：1
Because of long-term stream-flow cut off in the lower reaches of Tarim River, environmental degradation has become the most
severe and widespread environmental problem in Tarim River basin. Nine ecological water conveyances to the lower reaches of
Tarim River made ecological environment change a lot. 3S technology was used to monitor dynamic change of ecology. However,
remote sensing area index cannot analyze ecological restoration degree of Tarim River precisely because the time of each water
conveyance is short, the change of vegetation area is not obvious, and there exists visual interpretation error. In this paper,
remote monitoring datum of high temporal resolution and high spatial resolution were used to research the relationships between
normalized difference vegetation index (NDVI) and the groundwater depth, between NDVI and the surface vegetation coverage,
and between the groundwater depth and the surface vegetation coverage. The growth and restoration of the vegetation in different
periods were evaluated by investigative analysis of the change trend of NDVI. The conception of relative restoration degree
was proposed and the response of vegetation restoration to the water conveyance was evaluated. The evaluation result suggests
that: first, the response of vegetation to the water conveyance concentrates within 1,000 m of both riversides, and the range
of influence becomes smaller along the lower reaches of Tarim River. Second, influenced by the groundwater recharge, the vegetation
coverage shows decreasing trend with the increase of off-river distance. Third, the vegetation coverage shows decreasing trend
along the watercourse influenced by the water consumption. Finally, in spatial, original scattered meadow of low coverage
transforms to high coverage gradually in research region. Vegetation response to the water conveyance expands to both sides
with the watercourse being the axis, and expanding scale increases continuously. 相似文献
16.
陕北能源化工基地地下水开发的植被生态效应及对策 总被引：5，自引：2，他引：3
为了建立陕北能源基地基于生态良性循环的地下水开发利用模式,依据生态学和水文地质学原理,采用生态-水文地质调查与遥感定量分析相结合的方法,在研究陕北能源化工基地的植被生态空间分布特征、近30年来的演化趋势和影响因素的基础上,从植物类型、植物根系、植被指数与潜水埋深对比分析入手,建立了本区地下水位埋深与植被生态的依存关系,确定了影响植被生态的地下水位阈值,并开展了地下水开发的植被生态环境效应敏感性区划,提出了基于生态良性循环的地下水资源开发利用对策。 相似文献
17.
下辽河平原地下水生态水位与可持续开发调控研究 总被引：3，自引：1，他引：2
下辽河平原是辽宁省老工业基地的核心地区,水资源问题已经成为制约该区经济发展和生态环境改善的重要因素。地下水资源在整个供水系统中一直占有65%左右的比例,但由于地下水开采所导致的环境水文地质问题也很严重,因此开展研究区内的地下水生态水位及其调控的研究具有重要的意义。首先在研究区内降水入渗与蒸发规律的基础上,结合野外试验资料,采用情景分析的方法,设置了两种情景下地下水生态水位标准,并在第二种情景里又分为考虑地下水调蓄功能与不考虑地下水调蓄功能两种方案;然后通过对地下水实际埋深与生态水位埋深的比较,结合相应的水文地质参数,计算出各种方案下满足地下水生态水位要求的地下水调控量;最后论述了研究区内地下水资源可持续开发利用的对策措施。研究成果对于区内地下水资源的科学开采与有效保护具有一定的参考意义。 相似文献
18.
黄河流域中上游矿区煤?水矛盾突出,煤炭开采对地下水环境造成一定的破坏。基于此,以鄂尔多斯盆地北部侏罗纪煤田榆神府矿区为研究区,在野外调查、数据分析、室内测试的基础上,分析研究区矿井水的量质特征,揭示煤炭高强度开采对地下水环境的影响,并开展矿井水生态利用研究。结果表明:研究区矿井富水系数在0.23~2.28,平均为0.91,评估2020年区内矿井排水量高达4.70亿m3,受采掘活动影响,浅埋煤层开采区地下水位下降趋势明显;区内矿井水出现不同程度的污染组分超标现象,主要超标指标为化学需氧量(COD)、Na+、SO4 2?、溶解性总固体(TDS),未处理的矿井水外排将会污染区内地下水环境;研究区浅层地下水超限的水质指标主要为NO3-N,与矿井水超限水质指标差别较大,反映出浅层地下水水质受采矿活动影响较小;提出矿井水浅层回灌和矿井水生态灌溉2种模式开展研究区矿井水的生态利用,矿井水回灌对矿井水中的溶解性有机碳、色度具有较好的去除效果,回灌后出水满足Ⅲ类地下水限值;浅埋煤矿矿井水具有作为矿区生态修复灌溉用水的较好潜力,中深埋煤矿和深埋煤矿矿井水不适宜作为灌溉用水。研究结果为我国西部煤矿区水资源保护和生态修复提供重要依据。 相似文献
19.
西北干旱区地下水生态功能评价指标体系构建与应用 总被引：2，自引：0，他引：2
西北干旱区降水稀少、蒸发强烈,水资源紧缺,自然湖泊湿地、天然植被绿洲和土壤盐渍化程度对地下水生态水位具有强烈依赖性,因此,西北干旱区地下水生态功能评价指标体系构建成为一个重要课题.本文基于对干旱区不同类型生态状况与地下水位埋深之间关系的机制研究,构建了以浅层地下水埋藏状况为核心要素的"西北干旱区地下水生态功能评价指标体系",它由地下水对自然湿地景观维持性、天然植被绿洲维持性、农田土地质量维持性及其隶属的6项要素指标构成;在石羊河流域中、下游平原区应用结果表明,该套指标体系可为西北干旱区地下水功能评价提供参考,同时还表征石羊河流域中、下游平原区地下水生态功能脆弱,生态功能较弱和弱的分布范围占示范应用区总面积的87.86％,地下水生态功能强、较强分布范围仅占5.07％.由此可见,进一步提高西北干旱区地下水生态功能保护能力刻不容缓. 相似文献
20.
陕北能源化工基地资源开发引起的植被生态风险 总被引：5，自引：1，他引：4
地下水和煤炭资源开发是否会破环生态环境,以及会给生态环境安全带来多大的风险,是陕北能源化工基地资源开发和生态环境保护中不可逾越的课题。以陕北能源化工基地生态环境最为脆弱的风沙滩地区为研究区,在研究地下水位埋深与植被生态关系的基础上,建立了不同地貌类型、不同潜水水位埋深对应的植被群落类型和植被指数的分布关系,利用Modflow软件建立了风沙滩地区地下水流数值模拟模型,采用蒙特卡洛方法建立了植被生态随机模型,根据地下水水位埋深与植被生态的关系实现了地下水流模型和植被生态模型的耦合求解,对地下水资源和煤炭资源开发可能引起的植被生态变化进行预测和风险评估。 相似文献