共查询到20条相似文献，搜索用时 300 毫秒
1.
塔里木河下游植被生态需水量(英文) 总被引：4，自引：0，他引：4
We have appraised the relationships between soil moisture,groundwater depth, and plant species diversity in the lower reaches of the Tarim River in western China,by analyzing field data from 25 monitoring wells across eight study sites and 25 permanent vegetation survey plots.It is noted that groundwater depth,soil moisture and plant species diversity are closely related.It has been proven that the critical phreatic water depth is five meters in the lower reaches of the Tarim River.We acquired the mean phreatic evaporation of different groundwater levels every month by averaging the two results of phreatic evaporation using the Qunk and Averyanov formulas.Based on different vegetation types and acreage with different groundwater depth,the total ecological water demand(EWD)of natural vegetation in 2005 was 2.4×108m 3in the lower reaches of the Tarim River.Analyzing the monthly EWD,we found that the EWD in the growth season(from April to September)is 81%of the year's total EWD.The EWD in May,June and July was 47%of the year's total EWD,which indicates the best time for dispensing artificial water.This research aims at realizing the sustainable development of water resources and provides a scientific basis for water resource management and sound collocation of the Tarim River Basin. 相似文献
2.
We analyzed dust event occurrence and its seasonal distribution at 16 sites in the Tarim Basin,China.Although the overall frequency of dust events was the highest in spring in this region,its variation in other seasons could be classified into three patterns:(1) frequency of dust events in autumn > that in summer > that in winter(at the Kashi and Kuche sites);(2) frequency in summer > that in winter > that in autumn(at the Ruoqiang site);and(3) frequency in summer > that in autumn > that in winter(at all other areas of the Tarim Basin).The frequency of dust events and their seasonal variations in the Tarim Basin were mainly controlled by wind speed and locally available dust sources;the former was the key control when dust sources did not differ significantly.The seasonal variation in evaporation had a smaller,but still significant effect on the frequency of dust events. 相似文献
3.
Using NCEP/NCAR reanalysis data and the sand-storm frequency data fi＇om 37 weather stations in the Tarim Basin for the period 1961-2009, the relationship between the frequency of spring sandstorms in the Tafim Basin and the associated atmospheric circu- lation pattems is analyzed in this study. We found significantly negative correlations between sandstorm frequency and the 500-hPa geopotential height over the Paris Basin and midwestem Mongolia, while there were positive correlations over the Ural River region. The rising of the 500-hPa geopotential height in midwestem Mongolia and its falling over the Ural region corre- spond to a weakening of the large-scale wave patterns in the Eurasian region, which directly causes the frequency of the sand-dust storms in the Tarim Basin to decline. Also, the abrupt decline in the spring sandstorm frequency in the Tarim Basin observed in the last half-century is associated with profound changes in the atmospheric circulation in these key regions. At the interannual scale, the strengthened cyclonic atmospheric circulation patterns in the western part of Mongolia and the anticyclonic patterns over the East European plains at 500-hPa geopotential height, are responsible for frequent sandstorm occurrences in the Tarim Basin. 相似文献
4.
塔里木河下游土壤水分和地下水位变化对植被的影响 总被引：4，自引：0，他引：4
Based on data collected over five years of monitoring the Lower Tarim River,we analyzed the variability of soil moisture content (SMC) and the relationship between SMC,groundwater table depth (GWD) and vegetation by using the methods of coefficient of variation (Cv),Pearson correlation and regression. The results of the variability of SMC indicate that it rose with increase in depth of soil layer -SMC in the soil layer of 0-60 cm was relatively small compared to SMC in the soil layer of 100-260 cm which showed a significant increase in variability. SMC and GWD before and after ecological water diversions exhibited significant differences at the site of the Yingsu transect and its vicinity of the watercourse,especially SMC in the soil layer of 100-260 cm increased significantly with a significant rise of GWD and reached maximum values at a GWD of about 4 m. Plant coverage and species diversity significantly improved with increases in SMC in the soil layer of 100-260 cm,both of them approached the maximum values and 92.3% of major plant species were able to grow when SMC was > 10%. To restore the ecosystem of desert riparian forest along the Lower Tarim River,the GWD must be maintained at < 4 m in the vicinity of the watercourse and at about 4 m for the rest of this arid region. 相似文献
5.
Based on monitored data from 840 samples, we assessed the spatial and temporal variability of groundwater salinization in the Tarim River lower reaches combining classical statistics and geostatistics. Results show that total dissolved solids （TDS） is significantly correlated with other related ions, such as Na＋, Mg2＋, Ca2-, C1- and K＋. TDS and underground water level have characteristics of spatial autocorrelation, both of which present the isotropic characteristic and con- form to the spherical model in each year from 2001-2009. TDS is basically greater than 1 g/L but less than 2 g/L in the Tarim River lower reaches, which indicates that salt stagnation pollution is more serious. The most serious salinization （3 g/L 〈 TDS _〈 35 g/L） contaminated area is mainly in the middle and lower part of the study area. 相似文献
6.
Plant communities were sampled in the lower reaches of the Tarim River,Xinjiang,The results showed that there are 23 species belonging to 21 genera in 11 families,most of which have low occurrence frequency in quadrats.The most common species is Tamarix ramosissima,which occurred in 17 sites accounting for 89.47% of the total 19 sites,Quantitative classification (TWINSPAN) and ordination(CCA) methods were used to study the distribution Patterns of 23 plant species in 19 sites in this valley.TWINSPAN results showed that the plant communities in the middle reaches of the Tarim River could be divided into 3 groups and the sampling sites could be diveded into 7 types in 3 groups .CCA results were consistent with TWINSPAN results ,and showed species distribution patterns correlated with major environmental variables of groundwater level and soil moisture. 相似文献
7.
塔里木河流域水资源变化的特点与趋势 总被引：1，自引：1，他引：0
The Tarim RiverBasin islocated in NorthwestChina,which is known in the world forits rich natural resources and fragile eco-environment.W ater resource rational distribution and highly effective utilization isthe key pointsto solve the severe eco-environm … 相似文献
8.
Based on monitored data from 840 samples, we assessed the spatial and temporal variability of groundwater salinization
in the Tarim River lower reaches combining classical statistics and geostatistics. Results show that total dissolved solids
(TDS) is significantly correlated with other related ions, such as Na+, Mg2+, Ca2+, Cl? and K+. TDS and underground
water level have characteristics of spatial autocorrelation, both of which present the isotropic characteristic and conform
to the spherical model in each year from 2001–2009. TDS is basically greater than 1 g/L but less than 2 g/L in the
Tarim River lower reaches, which indicates that salt stagnation pollution is more serious. The most serious salinization
(3 g/L < TDS ≤ 35 g/L) contaminated area is mainly in the middle and lower part of the study area. 相似文献
9.
《地理学报》2002,(6)
No.1Analysis of Wind Erosion Caused Landscape Change and Its Relation with Spatial Distribution of Wind Energy ZHANGGuopingLIUJiyuanZHANGZengxiangetal.( 10 )Natural Eco-environmental Evaluation of West Route Area of Interbasin Water Transfer Project YANGShengtianLIUChangmingYANGZhifengetal.( 18 )Oasis Land Cover Change in the South Edge of Tarim Basi nDINGJianliTashpolat·TiyipXIONGHeigang( 27 )Modelling the Vegetation of… 相似文献
10.
Based on the palaeoclimatic and palaeoenvironmental evidences of geological history and human history periods, this paper reviews the researches and progresses on the development of the sandy deserts in Xinjiang. It pointed out that the features of tectonic structure in Xinjiang had made both the Tarim Basin and the Junggar Basin being influenced greatly by the foehn effects originated from the planetary wind system of westerly, the East Asian ocean-continental monsoon and the topographical mountain-valley winds. The regional patterns of climate and environment since the Quaternary were characterized by the overall persistent drought accompanied by fluctuations in the secondary scale. Formations of aeolian sediments in the basins and at the margins are a potential response to global climate change, particularly the aridification of the Asian hinterland deduced by the uprising of the Tibetan Plateau and its surrounding highlands. For the question about the formation time of the Taklamakan Desert, because the research methods, objects and information carriers used in previous studies are different, there are many disputes in the academic circles at present. Evidences from aeolian deposits/rocks at the edge and in the hinterland of these sandy deserts and their chronological data indicate that an arid climate and land surface aeolian processes have occurred at the edge of the Tarim Basin and its hinterland areas since the Tertiary period. However, the duration time of these processes at mass scale should have begun after the middle Pleistocene and lasted to the Holocene. Occurrence of dune fields in recent 2000 years in the oasis areas should be greatly influenced by human factors. 相似文献
11.
The lower reaches of the Tarim River are one of the areas suffering from most severe sandy desertification in Xinjiang, Northwest China. Irrational utilization of water and land resources results in eco-environmental deterioration in the Tarim River. In May 2000, the local government carried out the water conveyances project in the Tarim River. The influence of water conveyance on desertification reversion is analyzed and discussed according to the monitoring data in the past three years. Based on monitored data of the nine observed sections, along the channel of conveyance, the intensity and scope of desertification reversion in the upper reaches are larger than those in the lower reaches. Dynamic changes of desertification reversion are more obvious from the channel of conveyance to its two sides. However, the range of influence and intensity of desertification reversion is limited at present. It is suggested that the way and range of water conveyances should be adjusted in the future. 相似文献
12.
塔里木河下游生态输水对沙漠化逆转的影响 总被引：23，自引：14，他引：9
塔里木河下游是我国沙漠化最严重的地区之一。由于人类不合理的资源开发, 导致320km河道断流、大面积湿地消失、地下水位大幅度下降、天然植被全面衰败, 沙漠化程度加重。作者结合塔里木河下游生态输水和近3a的实地监测资料, 分析输水前后塔里木河下游典型地区沙漠化程度的变化, 并就生态输水对塔里木河下游沙漠化逆转的影响进行了讨论。结果表明, 生态输水后, 河道附近地下水位大幅度抬升, 植被种类和盖度明显增加, 部分地区沙漠化得到逆转。从实现逆转的沙漠化土地的空间分布看, 在纵横两个方向上表现出明显的变化规律, 在纵向上表现为上游土地沙漠化逆转的强度和范围较下游大; 在横向上, 表现为距输水河道越近变化越明显的特点。考虑到输水影响范围较小, 建议对现行的输水方式和输水规模进行适当调整。 相似文献
13.
大型输水工程的生态效益与社会经济效益评价——以塔里木河下游为例 总被引：1，自引：0，他引：1
基于塔里木河下游2000年、2010年、2016年3期的遥感资料,对区域内的土地类型进行分类,评估整个区域的生态系统服务价值变化特征,并应用主成分分析法等估算区域的社会经济评价分值。结果表明：① 自生态输水以来,塔里木河下游地区的未利用地面积变化不大,水域面积增加最显著,耕地和建筑用地面积有所增加,林地和草地的面积有所减少。② 2000~2016年,塔里木河下游生态系统各项服务功能价值有所增加,其中以提供美学景观价值和气体调节的价值增加最大,增加率分别为318.35%,312.94%;生态系统服务总价值增加率约为69.57%。③ 影响塔里木河下游经济发展的因素可以概括为经济地理因素与农业发展水平。 相似文献
14.
生态输水是塔里木河流域退化胡杨林生态恢复的主要措施,及时监测和准确评估其恢复成效是优化输水策略、完善胡杨林修复体系的关键。以2013年以来8个胡杨林区为研究对象,基于中高分辨率遥感数据监测不同胡杨林区生态输水前后植被面积、长势及植被覆盖度的时序变化,探讨胡杨林恢复与生态输水的关系。结果表明：（1） 2016年以来整个流域累计漫溢水面为2172.96 km2,占林区总面积的4.39%,主要分布在输水通道两侧及末端10 km范围内。（2） 输水前后林区植被整体呈现由退化到恢复的转变,林区生态恢复水平与年最大漫溢面积显著正相关。（3） 生态恢复成效评估表明,生态恢复最显著的区域是塔里木河中上游和叶尔羌河下游的夏马勒林场,但整个流域远离输水通道的胡杨林仍有退化趋势。合理规划输水通道建设,扩大胡杨林区的受水范围是退化胡杨林生态恢复的关键。 相似文献
15.
基于栅格尺度的沙漠化预警模型研究——以塔里木河下游中段区域为例 总被引：2，自引：0，他引：2
以塔里木河下游为研究区,基于沙漠化在气候、地表和人文3方面的成因构建沙漠化预警指标体系,并建立预警模型;基于研究区1990年、2000年和2006年的遥感、气候、地表和人文数据,利用ArcGIS对各因子数据进行量化和栅格化处理,通过预警模型实现了研究区3个时期在栅格尺度上（30 m×30 m）的沙漠化程度分布,分别利用前两期和第3期的结果进行参数修正和验证;在此基础上预测研究区“间歇输水”和“无输水”情况下2015年的沙漠化发展趋势。通过参数修正、预警模型对研究区沙漠化程度分布模拟正确率达90%以上,预警模型适用性较好。间歇输水对塔里木河下游沙漠化逆转起到一定的作用,是防止其完全沙漠化的必要措施,但此逆转作用基本上只局限于沿河道有限范围内,无法彻底改变研究区的沙漠化现状。 相似文献
16.
17.
塔里木河下游地下水位对植被的影响 总被引：133，自引：5，他引：128
对塔里木河下游断流河道2000~2002年9个地下水监测断面和18个植被样地的实地监测资料分析表明,地下水埋深对天然植被的组成、分布及长势有直接关系。地下水位的不断下降和土壤含水率大大丧失是引起塔里木河下游植被退化的主导因子。塔里木河下游的四次输水对其下游地下水位抬升起到了积极作用,河道附近地下水位呈逐级抬升过程,横向影响范围达1000 m左右,纵向上,表现为上段地下水抬升幅度较大 (达84%),下段抬升幅度较小 (6%)。随着地下水位的抬升,天然植被的响应范围由第一次输水后的200~250 m,扩展到第四次输水的800 m。 相似文献
18.
应用因子分析研究塔里木河下游生态环境的退化 总被引：10，自引：6，他引：4
采用SPSS分析软件,对塔里木河下游沿河道布设的39个样地进行了环境退化的因子分析。通过数学变换,9个观测指标被转换为2个综合指标(主分量)。根据本地区的实际,对2个综合指标进行了环境解释。依据这2个主分量的贡献率计算了塔里木河下游39个样地的因子得分,并据此进行了环境退化程度(荒漠化)的评价。从因子得分结果看,塔里木河下游地区呈明显的随距大西海予水库距离的增加荒漠化程度加重的特点,引起这一结果的主要原因是水、盐条件逐渐恶化带来的植被衰败。从分类的结果看,与本地区的实际基本相符合。这说明因子分析的方法综合了多指标的综合影响,划分的结果更加客观。 相似文献
19.
断流河道输水对地下水净补给量研究——以塔里木河下游为例 总被引：4，自引：2，他引：2
依据塔里木河下游断流河道2000—2006年8次生态输水期间地下水埋深监测数据,拟合了输水后地下水埋深与离河距离关系的曲线方程,进而对输水后地下水的补给量及其变化特征进行了计算和分析,探讨了生态输水的横向影响范围及其变化特点。结果表明,塔里木河下游区域输水后地下水总净补给量为7.82487亿m3,占总下泄水量的35.63％。8次输水过程中,除第2次输水和第6次输水外,其余各次输水期间,地下水净补给量都呈下降趋势。对输水后横向影响范围的分析表明,横向影响范围与输水量大小和持续时间密切相关。随着输水的进行,横向影响范围呈明显扩大趋势,纵向上各断面的横向影响范围的变化表现出了局部波动,整体变化与距离输水源头远近呈弱相关性的特点。 相似文献
20.
新疆塔里木河下游断流河道输水对地下水变化的影响分析 总被引：14，自引：4，他引：10
结合2000～2002年以来塔里木河下游间歇性输水后地下水变化的监测数据．用回归分析的方法对输水后地下水位动态响应变化过程进行分析,揭示输水量与地下水的响应范围之间的关系。结果表明：在横向上．随着向塔河生态输水次数和输水量的增加．地下水的响应范围逐渐扩大．但随远离输水河槽中轴线,响应程度减小．地下水位的抬升幅度减弱;纵向上,输水河段上游区段地下水位响应范围最大,中游区段次之,下游区段较小。在第二次输水过程中,靠近河岸地下水位出现急剧上升,而在第三次输水过程中,地下水的响应范围则有巨幅增加．输水量与输水持续时间与地下水位变化有着密切关系。 相似文献