西北干旱区额济纳绿洲水资源与生态环境保护对策

分析黑河流域下游额济纳绿洲水资源与生态环境的关系 .由于流域中、上游地区用水量逐年增加 ,使上游来水量逐渐减少 ,导致额济纳河由常年流水变成季节性流水 ,造成额济纳绿洲地下水位持续下降、水质恶化、植被退化、土地沙漠化 ,以及沙尘暴危害加剧 ,使绿洲生态环境严重恶化 .为保护和恢复额济纳绿洲 ,使社会经济可持续发展 ,应采取一系列生态环境保护对策 ,包括实施流域水资源分配 ,合理配置水资源 ;加强节约用水 ,发展高效农业 ,提高水资源利用率 ;搞好生态环境建设及水源保护 ,搞好流域规划 ,加强水资源管理和基础研究等工作 .     

基于正切模型的额济纳绿洲生态需水研究

基于RS解译和实测径流资料,分析了额济纳绿洲生态状况与水资源的关系,结果表明,无论从时间尺度上还是从空间尺度上,额济纳绿洲生态演变和水资源之间均具有明显的正相关关系,水资源减少是生态退化的决定性因素。在此基础上,结合西北内陆河产水和用水特点,提出了产流较弱的绿洲区生态需水量是为维持一定规模绿洲所需区外补给水量这一观点,并建立了额济纳绿洲生态需水计算的“正切”模型,通过与其他方法的比较,验证了模型的合理性,该方法可为北方缺水地区绿洲生态需水分析计算和水资源管理方案的合理制定提供决策依据。     

银根-额济纳旗盆地含油气系统特征与油气勘探前景

银根－额济纳旗盆地是陆上油气勘探的一个新区,面积大,勘察程度低。最新勘探表明,银根－额济纳旗盆地是自海西期四大板块碰撞形成大陆后在其板内演化过程中出现的中生代拉裂盆地群。该盆地群由单一的、彼此分隔的北东或北东东向箕状断陷组成。形成于株罗纪和早白垩世两个时期,相应形成了两套含油气系统。从区域地质背景出发,分别介绍了侏罗系（？）含油气系统和下白垩统（？）含油气系统的地质基本要素特征及要素特征及地质作用过程,分析了二者各自的含油气远景,指出了盆地的油气勘探方向。     

近50年来额济纳三角洲气象要素变化对蒸发皿蒸发量的影响

识别蒸发皿蒸发量与气象要素的关系是认识气候变化对水循环影响的重要基础。根据额济纳旗气象站1961年-2001年的常规气象数据,建立了额济纳三角洲地区蒸发皿蒸发量与相关气象要素关系的Penpan模型,并据此估算了2002年-2011年的蒸发皿蒸发量,延展了蒸发皿蒸发量的时间序列,进而分析了1961年-2011年研究区蒸发皿蒸发量和相关气象要素的变化趋势及其相互关系。研究结果表明:(1)1961年-2011年期间,额济纳三角洲蒸发皿蒸发量呈下降趋势(气候倾向率为年-215.5mm/10a),而平均气温呈上升趋势,风速、总辐射、相对湿度则均呈下降趋势;(2)总体上,蒸发皿蒸发量对各气象因子的敏感程度从大到小依次为风速、相对湿度、太阳总辐射、平均气温;1961年-2011年,蒸发皿蒸发量对风速、相对湿度的敏感性呈下降趋势,对太阳总辐射、平均气温的敏感性呈上升趋势;(3)风速变化对蒸发皿蒸发量变化的贡献度最大,其次是相对湿度、平均气温、总辐射。     

黑河中游张掖绿洲灌溉渠系的数字化制图与结构分析

人工灌溉渠系对于干旱区内陆河绿洲的生存和发展具有重要作用。以黑河中游的张掖绿洲为例,在收集大量高分辨率遥感影像和地形图资料的基础上,利用GPS实地测量和GIS软件提取了全绿洲干、支、斗3级渠系信息,获得了翔实准确的灌溉渠系空间和属性数据,首次完成了张掖绿洲灌溉渠系的数字化制图并对该渠系网络的空间格局进行了分析。结果表明：张掖绿洲目前渠道总数约为6 300条,总长为8 749.51 km,密度为0.47 km/km²,干、支、斗渠的比例为1∶1.17∶2.4。5个县区中甘州区的灌溉渠系分布最密集,而山丹县渠系建设相对落后。 绿洲人工灌溉渠系建设方式和水资源利用开发程度是影响和改变本地区流域景观结构和土地利用方式的重要因素。     

AL-ULA OASIS AND THE LOST CIVILIZATION

This article firstly explores how Al-Ula, an ancient city in northwestern Arabian Peninsula, thrived historically despite little rainfall, and reviews the historic civilizations ruled this oasis. Then, it points out that the misuse of limited water resource degraded the environmental capacity of the oasis, resulting in the imbalance between humans and the land and eventually the decline of civilizations. Finally, the article concludes that the oasis and the watershed it depends on is an integral system, whose lifeblood is maintained by water cycle restoration. It is also one of the key tasks of Landscape Architecture to explore ecological restoration and sustainable management of watershed in the sense of hydrology.     

绿洲地区葡萄生态适应性初步分析

葡萄是绿洲农区最重要的果品之一,但目前对绿洲地区葡萄适应性的研究较少.本文通过对绿洲农区的光、热、水、土资源与葡萄的耦合效应研究,分析了葡萄的生态适应性.结果表明:绿洲农区葡萄在长期的环境驯化过程中,已经形成了对不同生态条件的绿洲生态型的适应性.为了提高葡萄对绿洲生态条件的适应性,应该设法实现葡萄的供求、生态位及栽培模式的多元化.     

传统民居中的生态建筑经验刍议——以哈密市五堡乡博斯坦村为例

该文从地域建筑对自然环境的适应性出发,结合哈密市五堡乡博斯坦传统民居的生态建筑理念和技术,对哈密传统民居中的生态建筑经验进行了初步的总结,并论述了传统建筑建构方式来自于自然生态环境。     

西北干旱区绿洲型城市空间演变及其动因分析——以库尔勒为例

库尔勒作为西北干旱区典型的绿洲型城市其城市形态呈现出阶段性发展,表现为点状积聚、飞地扩散、填充拓展、郊区新城的空间特征,并形成了适应孔雀河水系发展的组团格局。本文运用城市形态学、空间紧凑度、分形维数等分析方法对其空间格局及形态进行了梳理分析。结论表明其发展受其绿洲自然条件及资源禀赋、区位优势及交通结构、经济及社会发展和政策引导及项目驱动的影响,其中自然因素是库尔勒城市发展之本,区位优势及交通结构是决定性因素;资源条件、区位优势、产业发展等是库尔勒城市发展的内在动力;政策推动以及城市建设等因素则起到了重要的催化作用。这就要求城市发展必须整合现有优势和资源走生态可持续发展之路。     

Typology of oases in northern Oman based on Landsat and SRTM imagery and geological survey data

In the desert country of Oman, available water resources are scarce and scattered. In most locations where water can be accessed, this resource is harnessed by oases planted to date palm (Phoenix dactylifera L.) and other crops. So far, little is known about the site-specific conditions determining the existence, size and type of these oases. Remote sensing and image processing techniques were used to locate oases, to characterize the sites according to their topographic, hydrologic and geologic characteristics and to develop a typology of oases in northern Oman.To derive oasis positions, we calculated the Normalized Difference Vegetation Index (NDVI) of Landsat images covering all of northern Oman, subtracted a regional average NDVI, averaged the resulting grid over 3 × 3 pixels and extracted the brightest of five classes determined by a natural breaks algorithm. A buffer of six pixels was added to the oases and the vegetated area as determined by the NDVI was summarized for these polygons. The oasis detection procedure was validated using Google Earth Pro®. Topographic information was derived from data of the Shuttle Radar Topography Mission (SRTM), complemented by digitized Russian military maps, from which mean elevations and elevation range above the oases within a buffer of 2 km were extracted.Water contributing upslope area and distance to streams with catchments of 10 km² and 100 km² were derived from the same elevation model. All geologic formations of northern Oman were assigned to one of 7 groups and tested for influence on vegetation surrounding them. Four such geologic settings were identified and described by categorical variables. All input parameters were used to define oasis types based on cluster analysis.Our algorithm detected 2663 oases in northern Oman, of which 2428 had vegetated areas of more than 0.4 ha, the minimum size for reliable detection. The oases were subdivided into six groups. ‘Plain Oases’ (49% of all oases) lie mostly in the plains east and west of the mountains, and are fed by groundwater flow in Quaternary sediments. ‘Foothill Oases’ (46%) are scattered over the foothills, where they draw their water from groundwater flow that is channeled by rock formations. ‘Mountain Oases’ (3%) and ‘Kawr Oases’ (0.5%) lie in the mountains, close to an unconform boundary between limestones and confining rocks. ‘Drainage Oases’ (0.3%) are the largest oases in northern Oman. They lie close to a drainage channel, which drains the entire area west of the mountains. Finally, ‘Urban Oases’ (1.7%) consist of parks and sporting facilities, which do not lie in conclusive hydrologic settings.