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1.
Response of riparian vegetation to water-table changes in the lower reaches of Tarim River, Xinjiang Uygur, China 总被引：1，自引：0，他引：1
Yaning Chen Zhonghe Pang Yapeng Chen Weihong Li Changchun Xu Xinming Hao Xiang Huang Tianming Huang Zhaoxia Ye 《Hydrogeology Journal》2008,16(7):1371-1379
The lower reaches of Tarim River in the Xinjiang Uygur region of western China had been dried out for more than 30 years before water began to be diverted from Konqi (Peacock) River via a 927-km-long channel in year 2000, aimed at improving the riparian ecological systems. Since then, eight intermittent water deliveries have been carried out. To evaluate the response of riparian vegetation to these operations, the groundwater regime and vegetation changes have been monitored along the 350-km-long stem of the river using a network of 40 dug wells at nine transects across the river and 30 vegetation plots at key sites. Results show that the water table rose remarkably, i.e. from a depth of 9.87 m before the water delivery to 3.16 m after the third water delivery. The lateral distance of affected water table extended to 1,050 m from the riverbank after the fourth water delivery. The riparian vegetation has changed in composition, type, distribution, and growing behavior. This shows that the water deliveries have had significant effects on restoration of riparian ecosystems. 相似文献
2.
Desert riparian forest colonization in the lower reaches of Tarim River based on remote sensing analysis 总被引：1，自引：0，他引：1
Guilin Liu Alishir Kurban Huanming Duan Umut Halik Abdimijit Ablekim Luocheng Zhang 《Environmental Earth Sciences》2014,71(10):4579-4589
The ecological water conveyance project that pipes water from Daxihaizi reservoir to lower reaches of Tarim River has been implemented ten times since 2000. After ecological water conveyance, restoration has taken place for vegetation along the dried-up lower reaches of the Tarim River. The changes of vegetation fluctuated yearly due to ecological water conveyance. In order to reveal the detailed process of vegetation changes, remote sensing images from 1999 to 2010 were all classified individually into vegetated and non-vegetated areas using the soil-adjusted vegetation index threshold method. Then inter-annual changes of vegetation over a period of 12 years were obtained using a post-classification change detection technique. Finally, spatial–temporal changes distribution of vegetation cover and its response to ecological water conveyance were analyzed. The results indicate: (1) vegetation area increased by 8.52 % overall after ecological water conveyance. Vegetation between 2003 and 2004 increased dramatically with 45.87 % while vegetation between 2002 and 2003 decreased dramatically with 17.83 %. (2) Vegetation area gain is greater than vegetation loss during 1999–2000, 2001–2002, 2003–2004 and 2009–2010 periods. Although vegetation restoration is obvious from 1999 to 2010, vegetation loss also existed except for the periods above. It indicates that vegetation restoration fluctuated due to ecological water conveyance. (3) Spatial distribution of vegetation restoration presented “strip” distribution along the river and group shaper in the lower terrain area, while spatial distribution of vegetation loss mainly located in the upper reaches of river and area far away from the river. (4) Vegetation restoration area had a positive relative with total ecological water conveyance volume. The scheme and season of ecological water conveyance had also influenced the vegetation restoration. The vegetation change process monitoring, based on continuous remote sensing data, can provide the spatial–temporal distribution of vegetation cover in a large-scale area and scientific evidences for implementing ecological water conveyance in the lower Tarim River. 相似文献
3.
4.
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
5.
Statistical analysis of groundwater chemistry of the Tarim River lower reaches,Northwest China 总被引：2，自引：2，他引：0
Jianhua Xu Yaning Chen Weihong Li Lijun Zhang Yulian Hong Xueli Bi Yang Yang 《Environmental Earth Sciences》2012,65(6):1807-1820
This study applied a comprehensive quantitative approach including statistical, principal component and gray relation analyses
to assess the groundwater chemistry based on monitored data from 840 samples collected from the lower reaches of Tarim River
from 2000 to 2009. The main findings were: (1) there were six types of groundwater chemistry in the lower reaches of Tarim
River where Cl·SO4–Na·Mg was the dominant type accounting for 73.57% in all samples. There were linear relationships among chemical parameters,
where TDS had significant multiple correlations with Na+, K+, Mg2+, Ca2+ and Cl−, respectively. (2) Three principal components (PC1, PC2 and PC3) were extracted. They included comprehensive measurements
for salinization, alkalinity and pH, respectively. Most parameters showed decreasing trends during the period of 2000–2009,
as well as the scores on PC1, because the concentrations of various chemical substances were diluted due to the uplift of
the groundwater table in the lower reaches and the implementation of the ecological water delivery project in 2000. (3) HCO3
− was the most sensitive chemical parameter affected by the groundwater table followed by TA, Mg2+, TH, SO42−, K+, TDS and TS. PC2 was the most sensitive principal component to the change of the groundwater table followed by PC1 and PC3. 相似文献
6.
塔里木河下游357km河道断流近30年,向塔里木河下游实施应急输水抢救生态环境,是世界范围内流域退化生态系统恢复与重建的稀有案例。以此为背景,在生态环境本底状况调查的基础上,通过大量的监测资料,应用河道水力学、地下水动力学以及植被生态学,以河道水量沿程消耗-地下水位动态变化-植物恢复为主线,摸清了水流在河道纵向、河道横向两侧和垂向剖面中的运移、转化和消耗规律,研究分析了应急输水的水生态环境三维响应特征和植被恢复效应。为创建和完善干旱区受损生态系统输水、修复与重建的评价体系打下基础,也为塔里木河流域综合治理提供技术支撑。 相似文献
7.
塔里木河下游生态输水及植被恢复遥感监测评价 总被引：9，自引：1，他引：8
在干旱区内陆河流域,由于水资源过度开发利用,生态环境退化已成为普遍现象.向断流的河道和生态退化区域实施生态输水,是河流生态系统恢复的基本行为和必然过程.基于向塔里木河下游7次生态输水过程中地表水、地下水、植被恢复等系统监测,并运用卫星遥感技术,对生态输水后植被恢复响应特征指标NDVI(植被指数),进行了系统研究分析,并提出植被相对恢复度的评价方法. 相似文献
8.
The occurrence and development of riparian forests, which were mainly dominated by mesophytes species related closely with
surface water. Since there was no water discharged to the lower reaches of Tarim River in the past three decade years, the
riparian forests degrade severely. The groundwater table, the saline content of the groundwater, as well as the content of
free proline, soluble sugars, plant endogenous hormones (abscisic acid (ABA), and cytokinins (CTK)) of the leaves and relative
rates of sap flow of the Populus euphratica Oliv. (arbor species), Tamarix ramosissima Ldb. (bush species), and Apocynum venetum L. (herb species) were monitored and analyzed at the lower reaches of the Tarim River in the study area where five positions
on a transect were fixed at 100 m intervals along a sampling direction from riverbank to the sand dunes before and after water
release. The physiological responses and acclimation strategies of three species to variations in water and salinity stress
were discussed. It was found that A. venetum population recovered to groundwater table ranging from −1.73 to −3.56 m, and when exposed to saline content of the groundwater
ranging from 36.59 to 93.48 m mol/L; P. euphratica appeared to be more sensitive to the elevation of groundwater table than the A. venetum and T. ramosissima at groundwater table ranging from −5.08 to −5.80 m, and when exposed to saline content of the groundwater ranging from 42.17
to 49.55 m mol/L. T. ramosissima tended to be the best candidate species for reclamation in this hyper-arid area because it responded to groundwater table
ranging from −1.73 to −7.05 m, and when exposed to saline content of the groundwater ranging from 36.59 to 93.48 m mol/L.
These results explained the distribution patterns of desert vegetation in the lower reaches of the Tarim River. Understanding
the relationships among ecological factors variables, physiological response and acclimation strategies of plant individuals
could provide guidance to sustainable management, reclamation and development of this and similar regions. 相似文献
9.
Response of groundwater chemistry to water deliveries in the lower reaches of Tarim River,Northwest China 总被引：2，自引：0，他引：2
Yongjin Chen Kefa Zhou Yaning Chen Weihong Li Jiazhen Liu Tao Wang 《Environmental Geology》2008,53(6):1365-1373
In this paper, we analysed the monitored data from nine groundwater-monitoring transects in the lower reaches of Tarim River
during the five times of stream water deliveries to the river transect where the stream flow ceased. The results showed that
the groundwater depth in the lower reaches of Tarim River rose from −9.30 m before the conveyances to −8.17 and −6.50 m after
the first and second conveyances, −5.81 and −6.00 m after the third and fourth the conveyance, and −4.73 m after the fifth.
The horizontal extent of groundwater recharge was gradually enlarged along both sides of the channel of conveyance, i.e.,
from 250 m in width after the first conveyance to 1,050 m away from the channel after the fourth delivery. With the rising
groundwater level, the concentrations of major anions Cl−, SO42− and cations Ca2+, Mg2+, Na+, as well as total dissolved solids (TDS) in groundwater underwent a significant change. The spatial variations in groundwater
chemistry indicated that the groundwater chemistry at the transect near Daxihaizi Reservoir changed earlier than that farther
from it. In the same transect, the chemical variations were earlier in the monitoring well close to watercourse than that
farther away from the stream. In general, the concentration of the major ions and TDS at each monitoring well increased remarkably
when the water delivery started, and decreased with the continued water delivery, and then increased once again at the end
of the study period. Hence, the whole study period may be divided into three stages: the initial stage, the intermediate stage
and the later stage. According to the three stages of groundwater chemistry reaction to water delivery and the relationships
between groundwater chemical properties and groundwater depths, we educe that under the situation of water delivery, the optimum
groundwater depth in the lower reaches of the Tarim River should be −5 m. 相似文献
10.
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
11.
The changes in the depth of groundwater were studied from the period before water conveyance through 2010, and the TDS of groundwater was analyzed in the lower reaches of the Tarim River during the period 2001–2010. Besides, the numbers of juvenile P. euphratica were investigated in the lower reaches of the Tarim River during the period 2001–2010. The findings indicate that: (1) the hydrological environment of the lower reaches has slowly deteriorated again; and (2) few juvenile P. euphratica were observed along the channel. These results show that the positive influence of the ecological water conveyance project on the ecosystem of the lower Tarim River should be beneficial in the long term; however, the long-term stability of the ecosystem cannot be achieved by the current water diversion scheme. 相似文献
12.
13.
塔里木河下游的乔木、灌木、草本植被的主要建群种为胡杨、柽柳和罗布麻,对其中丙二醛(MDA)含量以及保护酶活性对地下水位的研究表明:1)MDA含量以及SOD、POD活性均呈增加趋势,而且均与地下水位呈正相关关系;2)对同一断面相同地下水位条件下胡杨、柽柳和罗布麻的SOD活性和POD活性比较,可以反映出SOD和POD作用的互补性;3)根据不同地下水位条件下胡杨、柽柳和罗布麻的MDA含量和SOD活性所反映出的适宜植物生存的合理生态水位、(严重)胁迫水位,并将其进行综合比较与分析,初步推断在塔里木河下游地下水埋深超过3.12 m时,胡杨和柽柳的生长即开始受到抑制,6 m左右的地下水位即对胡杨造成严重胁迫,≥8.83 m的地下水位则会危及胡杨的生存;而柽柳的严重胁迫地下水位以及临界地下水位分别为5 m左右和≥8.83 m.相比之下,罗布麻所能承受的胁迫地下水位比较高,超过3.12 m的地下水位即会对其生长造成严重水分胁迫,地下水位低于4.42 m则危及其生存. 相似文献
14.
由于中国西北地区地表水资源有限,地下水则成为重要的备用水资源,而地表水和地下水转化过程及其耦合模拟是水资源开发利用和科学评价的基础,因此,为了准确反映塔里木河下游间歇性生态输水后地下水的动态变化,以塔里木河下游英苏断面为例,基于Boussinesq方程建立了改进的地下水动力学(GH-D2)模型,模拟了塔里木河下游绿色走廊典型断面地下水对全时段(2000-2015年)间歇性生态输水的响应过程。结果表明,尽管Boussinesq方程的GH解能较好地模拟地下水位的瞬态变化,但模拟地下水位多年变化的结果并不理想,而改进的GH-D2模型考虑了间歇性生态输水对地下水位变化的滞后效应,对长时间尺度地下水位变化的模拟具有较好的效果。与GH和GH-D1模型相比,GH-D2模型模拟的地下水位值更接近于观测值,这将对塔里木河下游实施科学合理的生态输水计划以及生态恢复和重建策略提供关键的技术支撑。 相似文献
15.
Environmental changes after ecological water conveyance in the lower reaches of Heihe River,northwest China 总被引：3，自引：0，他引：3
This paper analyzed the dynamic change of the groundwater level by 6 years’ monitoring in field monitoring and the change
of vegetation by the field survey and satellite remote sensing after watering in the lower reaches of Heihe River. The findings
indicated: (1) the groundwater level elevation and the plant growth are closely related to the volume and the duration of
watering. In general, groundwater level elevates dramatically and plants are growing much more vigorously after watering;
(2) Watering incidence on groundwater keeps extending with the watering times increasing; (3) Plants grew rapidly in 100–400 m
away from the water channel after watering. Watering incidence on vegetation reached 1,000 m; (4) In terms of the function
and structure of ecosystem after watering in the lower reaches of Heihe River, the ecological water conveyance does not still
reach the goal of ecological restoration at a large spatial scale at present. In addition, in order to solve fundamentally
the problem of ecological environment worsens in the lower reaches of Heihe River, some suggestions and countermeasures are
put forward. 相似文献
16.
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
17.
塔里木河下游已经干涸断流多年,其"绿色走廊"濒临消失.自2000年5月至2001年11月,先后3次实施向塔里木河下游输水,使下游的水文状况得到了改善,生态得到了一定程度恢复.根据塔里木河下游3次应急输水的有关资料,在输水过程的分析与模拟方面进行了研究,重点是第2次输水过程的分析模拟.从流量沿程损失率及水头前进速度出发,模拟了历次输水的流量沿程分布、输水距离、输水历时及输水水量,为评价输水的水文效应及选择适当的输水方案提供了初步依据. 相似文献
18.
加强塔里木河阿拉尔生态系统综合监测 总被引：3，自引：0，他引：3
塔里木河流域是我国最大的内陆河流域,流域总面积102×104km2,水资源总量为429×108m3,水资源相对贫乏,生态环境十分脆弱.阿拉尔生态系统监测站位于阿克苏河、叶尔羌河、和田河三河和塔里木河交汇处的肖夹克,是平原区重要区域代表站,其生态环境直接关系着塔里木河干流上、中、下游生态和环境安全.查阅模清该区域的生态环境的基本特点、变化规律和演变趋势,对指导塔里木河综合治理,以及当地社会经济和谐发展极其重要.该站始建于1996年7月,监测项目有水文气象;地下水动态;乔、灌、草;土壤、水盐;沙漠化动态5类监测项目.野外监测设施有河道水文断面、气象观测场、第一监测剖面(长22 km).除水文气象监测项目在综合系统监测站附近外,其余4个监测项目均在第一剖面进行. 相似文献
19.
干旱区内陆河流域的生态安全与生态需水量研究 总被引：2，自引：0，他引：2
结合对干旱区生态安全和生态需水量关键科学问题的探讨,提出干旱内陆河流域生态脆弱区的生态安全分析是以水过程研究为核心的,水文过程控制着生态过程,对流域生态系统的稳定性有着直接影响,而水资源开发利用和水循环对生态系统功能有重要影响,天然植物恢复和生长的合理地下水位的研究是确立生态需水量的基础。并实证分析和计算了维系塔里木河生态安全的生态需水量,塔里木河干流现状生态需水量为31.74×108 m3,其中,上、中、下游分别为9.95×108m3、18.47×108m3和3.32×108m3。 相似文献
20.
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