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1.
The sustained development of an artificial oasis depends critically on the stability of the natural oasis associated with
it. This work theoretically investigates the most suitable ratio of natural oasis area to artificial oasis area in oasis ecosystems,
as quantified by the percentage of artificial oasis (PAO). Based on data from oases observed in Xinjiang Province, China,
this paper analyzes the PAO distribution for these oases via fractal theory. The results allowed us to draw the following
conclusions. (1) The PAO distribution possesses fractal characteristics, and the fractal dimension of the PAO decreases as
the oasis evolves. (2) The interval of the fractal dimension of the PAO is 0–1.7068, and the interval of the expectation of
the PAO is 0–85.01%. This indicates that the natural oasis should occupy at least around 15% of the total oasis area. (3)
The fractal dimension and the expectation of the PAO for the ecosystem of oases in Xinjiang Province, China, are currently
0.5369 and 53.51%, respectively. These results show that the development of artificial oases in Xinjiang Province should continue,
although the corresponding natural oases should also be maintained and developed at the same time. 相似文献
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水资源约束下的阿克苏河流域适宜绿洲规模分析 总被引:2,自引:0,他引:2
阿克苏绿洲是中纬度干旱区典型的绿洲灌溉系统,制定绿洲适宜发展规模、明确适宜耕地面积,可为实现绿洲的生态稳定与可持续管理提供科学依据。以中国西北干旱区的阿克苏河流域为研究对象,基于作物需水量和绿洲适宜面积模型的水热平衡法,借助典型绿洲结构模型,计算了阿克苏绿洲的适宜耕地面积。结果表明:2010-2015年阿克苏灌区的作物需水量高达740.3 mm,较20世纪60年代的539.6 mm增加了37.2%;考虑到山区来水和下泄塔里木河干流的水量要求,阿克苏绿洲的可用水量为42.6×108 m3;阿克苏河流域绿洲已处于不稳定状态,耕地面积超过了水资源承载能力。计算得出绿洲适宜规模为12 430 km2,与现有水平相当。基于作物需水量和绿洲适宜面积模型的水热平衡算法计算的阿克苏绿洲的适宜耕地面积分别为4 674 km2和4 211 km2,需要在当前耕地水平上退耕18%至26%。 相似文献
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应重视和加强我国沙漠绿洲的研究 总被引:2,自引:1,他引:2
把散布在我国干旱荒漠地带内的沙漠绿洲,统一组合成一种独特而完整的生成地域单元开展研究,应予重视和加强。沙漠绿洲是干旱荒漠地带内精华地域,也是今后该地带开发建设和经济发展基地,还是改造利用沙漠的潜力与希望所在。随着我国经济发展战略重点向西北转移,开发建设和整治利用沙漠绿洲,有着特别的重要性和紧迫性。 相似文献
5.
干旱地区内陆河流域水文问题的研究实践与展望 总被引:13,自引:0,他引:13
过去,干旱地区内陆河流域水文研究主要偏重于山区水文,注重山区来水及径流分析,而很少涉及灌区问题和生态问题,对绿洲水文和荒漠水文的研究十分缺乏。以新疆为例,通过对干旱地区河流的基本特征和水文机理的分析研究,从径流形成、水资源开发利用、生态环境保护三位一体,即从全流域水文循环的角度出发,提出了以山区水文、绿洲水文、荒漠生态水文为三大构成要素的干旱地区内陆河流域水文系统的新概念,并基于干旱地区内陆河流域水文问题的研究实践,提出了各自领域的研究内容和方向,进一步拓宽了水文问题的研究领域,对水文学科的研究与发展提出了新的思路,注入了新的内容。 相似文献
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干旱区绿洲地下水位调控方法与模型研究进展 总被引:1,自引:0,他引:1
适宜的地下水位是干旱区绿洲健康稳定发展的基础。从地下水生态水位的调控机理、调控方法、调控模型和应用实践入手,综述了干旱区绿洲地下水生态水位调控的研究进展:地表水与地下水相互转化规律是干旱区绿洲地下水生态水位调控的理论基础,掌握人类活动强烈影响下的地表水与地下水的响应关系是关键;地下水的补给、排泄和开发利用是实现地下水位调控的三个主要途径,不同调控方法在作用环节、适用性及效果方面存在显著差异;基于不同的研究重点,目前形成了以水资源配置、水循环过程和生态过程为核心的三类调控模型;建议继续深化强人类活动影响下干旱区绿洲生态水文响应机理与演变规律研究,构建基于调控措施-循环转化-响应反馈的地下水生态水位调控体系。 相似文献
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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
10.
近20余年来西北地区植被变化特征分析 总被引:27,自引:0,他引:27
利用1982—2003年8 km分辨率的NDVI数据集,选中国西北地区森林、草原、灌溉农业、雨养农业区不同类型植被为研究区,分析了植被年、年际变化特征,并对植被覆盖空间变化进行动态研究.结果表明:森林、草原、灌溉农业区和以春小麦为主的雨养农业区NDVI年变化为单峰型曲线,以冬小麦为主的雨养农业区NDVI曲线呈双峰型;同一类型的植被NDVI受纬度或海拔高度的影响,绿峰出现时间存在1个月的位相差.22 a来森林植被NDVI多呈下降趋势,草原植被区为上升趋势;雨养农业区变化不大,灌溉植被区呈显著的上升趋势.西北东部雨养农业区植被波动频率和幅度最大,是受降水影响最敏感的地区;森林植被次之;有灌溉条件的绿洲植被,年际间波动最小.22 a间西北地区植被以增加趋势为主,增加面积约为20.5%,主要分布在新疆和河西走廊绿洲、黄河沿岸灌区以及青海草区,水分条件充足的绿洲是NDVI增加最显著的区域;NDVI减少地区面积为4.77%,主要分布在西北东部. 相似文献
11.
地质学报 《《地质学报》英文版》2000,74(2):18-369
The arid area is one of the most concerned areas among the water resources researchers and economists. Northwest China will be an important developing region of China in the 21st century. Yaoba is a well-irrigation oasis within this arid area, which is located in the Alxa area west of the Helan Mountains and next to the Tengger desert in the east. It has contributed greatly to the local stock raising and agriculture since its development in 1970. However, the groundwater which the oasis depends on to survive has been getting salinized gradually and more serious in recent years.A comprehensive study was carried out using the methods of groundwater environment isotope analysis, lithofaci-es and palaeogeography, calculations of water-rock interaction and the existing form of chemical components in groundwater etc. It has been found that the salinization of groundwater is mainly caused by reinfiltration water solving the salt in soil which is deposited simultaneously with the sediments and accumulated in th 相似文献
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新疆开都-孔雀河流域绿洲需水量与稳定性分析 总被引:3,自引:0,他引:3
水是绿洲存在和发展的核心, 干旱区绿洲稳定性与水密切相关. 根据2000-2009年资料, 采用蒸发系数法和定额法估算开都-孔雀河流域绿洲自然生态系统和社会经济系统综合需水量, 并对水资源约束条件下的绿洲稳定性进行初步探讨. 结果表明: 2000-2009年, 绿洲年均总需水量理论值约为54.80×108 m3, 其中开都河绿洲总需水量约为20.55×108 m3, 孔雀河绿洲总需水量约为21.90×108 m3, 博斯腾湖区耗水量约为12.35×108 m3, 与绿洲10 a平均供水量相比, 供需表现出极大地不平衡性. 水资源可承载绿洲面积(不含博斯腾湖)约为3139.66 km2, 其中可承载灌溉地面积约为1395.41 km2, 与绿洲10 a平均面积5 248 km2相比, 差别较大, 绿洲处于不稳定状态, 现状绿洲面积应适当收缩. 最后, 对博斯腾湖最低生态水位进行讨论, 初步把大湖最低水位定为海拔1 045 m, 小湖最低生态水位定为海拔1 046.5 m. 相似文献
13.
沙漠—绿洲过渡带近地表风沙过程研究进展 总被引:1,自引:0,他引:1
受绿洲和沙漠景观格局的双重影响,沙漠—绿洲过渡带是一个对外界条件变化极为敏感的生态环境脆弱带。沙漠—绿洲过渡带近地表风沙过程及其动态演变直接影响绿洲的稳定和有序发展,在空间上制约沙漠的进退或绿洲的变迁。从沙漠—绿洲过渡带局地小气候、沙尘暴、风沙环境、土壤风蚀、风沙输移和绿洲防护体系建设等几个方面比较全面地综述了近数十年来沙漠—绿洲过渡带近地表风沙过程研究进展,并基于当前沙漠—绿洲过渡带生态环境建设与地方需要等面临的实际问题,分析了该领域今后的研究重点和发展趋势。 相似文献
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Qingqing Zhang Hailiang Xu Yan Li Zili Fan Peng Zhang Pujia Yu Hongbo Ling 《Environmental Earth Sciences》2012,66(2):683-692
The Manas River valley is a typical inland river basin of an arid area in central Asia, and illustrates oasis evolution and
economic development in this region. Based on the historical documents, monitoring data from field surveys, and remote sensing
image data, this paper illustrates the oases evolution over the last 2,000 years and analyzes the rapid expansion of the Manas
River oasis in the last 60 years. We also examine the relationship between oasis evolution and water resource utilization.
We discuss the characteristics and effects of oasis expansion and the proposed adjustment measures for sustainable development
of the Manas River valley. The principal objectives of this paper were to analyze the relationship between oasis expansion
and water resource utilization over the last 60 years, and to solve the conflict between the continuous expansion of oases
and a shortage of water resources to keep development of the Manas River valley sustainable. The results indicate that (1)
oasis evolution in the Manas River valley over 2,000 years can be divided into three periods: a period dominated by animal
husbandry, a period of semi-farming and semi-grazing, and a farming-dominated period. During the first two periods, the oasis
area was limited, water conservancy facilities were poor and water utilization levels were low. In the third period, oasis
expansion over the last 60 years shows a large-scale development. (2) The farming-dominated period can be subdivided into
four phases according to the scale of water projects and the level of irrigation. Different oasis scales of the four phases
show that artificial oasis evolution has a close connection with water resource utilization. (3) The evolution of oases in
the Manas River valley raises some environmental problems although it plays an active role in promoting sustainability. Therefore,
adjustment measures for the future development of oases could be proposed from the perspective of sustainable development,
such as oasis scale control, forbidding reclamation, moderating exploitation of groundwater, and transforming industrial structures. 相似文献
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绿洲耕地适宜面积确定与减灾研究——以新疆渭干河灌区为例 总被引:4,自引:0,他引:4
在干旱区,以农田为核心的绿洲规模过大,对绿洲的稳定性产生了广泛而深刻的影响。论文以位于塔里木盆地的渭干河为例,分析渭干河灌区当前所面临的主要风沙灾害,揭示了绿洲规模过大、农业耗水量过大。生态用水被侵占是导致农田生态环境恶化的重要原因。在此基础上,以水热平衡、水盐平衡理论分别计算了灌区适宜的规模与耕地面积。根据模型计算结果,提出了控制耕地规模、确保生态用水的宏观对策。 相似文献
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北疆玛纳斯河流域人工绿洲演变过程及其特点 总被引:5,自引:0,他引:5
利用历史文献资料、实地调查和监测资料, 并结合遥感影像解译数据, 分析了近2 000 a来玛纳斯河流域人工绿洲的演变进程, 探讨了人工绿洲扩展过程与水资源利用的关系以及绿洲扩张的特点. 结果显示: 近2 000 a来玛纳斯河流域人工绿洲的形成和演变可以分为4个时期: 17世纪以前以牧为主时期, 流域人工绿洲仅呈星点分布在交通要道和军事据点; 17世纪以后到1949年才进入半农半牧时期, 流域人工绿洲呈小块状分布在河、泉引水方便之处; 1949年以后玛纳斯河流域人工绿洲进入了以农为主时期, 人工绿洲由小片联接成大片, 扩大成新疆第四大绿洲群; 20世纪70年代以后城市化时期, 流域绿洲的二、三产业快速崛起.根据绿洲发展演变与水资源开发程度和灌溉水平将以农为主时期细分为4个阶段, 从4个阶段不同水利条件和灌溉水平下绿洲的规模可以看出人工绿洲的演变进程是与流域水资源利用水平紧密结合的; 玛纳斯河流域绿洲扩张的特点有: 人文因素对其有很大影响, 移民屯垦在绿洲发展中起了重要作用, 近60 a来人工绿洲面积成倍扩大, 尽管水利建设支撑绿洲发展, 但仍受到流域水资源的限制. 相似文献
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荒漠绿洲边缘凝结水量及其影响因子 总被引:16,自引:0,他引:16
以2004年7~10月在临泽内陆河流域综合研究站凝结水试验观测数据为基础,讨论了荒漠绿洲边缘凝结水凝结过程、不同下垫面凝结量及其影响因子.结果表明:荒漠绿洲边缘凝结水以吸湿凝结为主,北京时间16:00~18:00开始,至次日7:00~8:00结束.凝结开始的时间受控于沙地含水量,凝结量则主要受近地表相对湿度、近地表气温以及气温日较差三方面因素的影响.人工草地、平坦无植被沙地、沙丘顶部、丘间低地和人工林地在7~10月的平均月凝结量分别为:5.1 mm、4.0 mm、3.1mm、1.8 mm和1.0 mm. 相似文献
19.
甘肃河西地区内陆河流域荒漠化的水资源问题 总被引:25,自引:1,他引:24
河西地区内陆河流域荒漠化的水资源问题,根本的原因在于水资源短缺而导致的生态环境脆弱和水资源的过度开发利用.如果上、中游地区水资源的利用超过了水资源量的限度,则流到下游的径流量减沙,地下水位下降;而下游地区为了弥补水资源的不足,便大量开采地下水,致使地下水严重超采,从而导致植被退化和荒漠化.在分析上述问题的基础上,以石羊河为例,说明内陆河流域的荒漠化防治要求实行以农业节水为中心,建立节水型社会的流域综合治理,实现水资源、土地资源、经济、社会和生态环境协调和可持续发展. 相似文献
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Desert–oasis ecotone is an interactive area between desert and oasis ecosystems which plays an important role in ensuring
oasis ecological security and maintaining oasis internal stabilization. The studied region had experienced dramatic landscape
change and soil degradation during the 20th century, especially in the last two decades. To document the status and evaluate
this degradation process, geostatistics and GIS map algebra were used to quantify the temporal–spatial changes in landscape
pattern and soil degradation from 1983 to 2005. The results showed that: (1) the change of landscape pattern due to human
activities was the key reason responsible for the increasing of landscape diversity and fragmentation; (2) the extent of soil
degradation was higher near desert ecosystem than oasis, and human activities were the major driving forces in ameliorating
the soil properties; and (3) soil degradation is weaker in regions of bad soil quality than regions of good soil quality due
to both human activities and natural processes. 相似文献