伊犁河谷地下水及土壤盐分分布特征

利用化学分析和地统计学法,分析了研究区地下水以及土壤盐分含量、离子组成特征及其分布规律.结果显示:地下水矿化度平均值为2.37 g/L,pH值平均值为7.63,地下水中各阴离子含量由高到低依次为Cl-＞SO42-＞HCO3-＞CO32-,阳离子含量由高到低依次为Ca2+＞Na+＞Mg2+＞K+,地下水属于Cl--Ca2...     

基于MODS耦合的新疆玛纳斯河流域生态安全问题研究

干旱区山地-绿洲-荒漠系统（MODS）耦合关系,是在新疆山盆结构及水文循环共同作用下形成的,是内陆河流域生态系统稳定性和生态服务健康性的客观表达。用生态系统耦合原理、空间结构稳定性分析、土地类型及利用评价等方法,结合相关遥感影像分析,得出：绿洲开发改变了流域水文循环及水资源分配的有效性,圈层结构的脆弱组成-天然绿洲及过...     

塔里木河干流治理工程对天然植被的影响及对策建议

 塔里木河沿岸是我国胡杨林分布最集中的地区,在世界上占有极其重要的地位。塔里木河干流治理工程实施后,将对天然植被的生境产生一系列的影响。结合水资源配置,对天然植被进行保护和建设,对防止沙漠化、保护人工绿洲具有重要的意义。介绍塔里木河干流植被分布特征、干流治理工程布局及水资源配置,分析治理工程对天然植被的影响,提出了保护对策建议。     

黑河流域防风固沙林生态效益研究——以甘肃省高台县为例

通过对黑河流域高台地区防风固沙林体系的定位观测,分析了该区防风固沙林20年来的生态效益变化。研究结果表明:在防风固沙效益方面,花棒×柠条锦鸡儿×梭梭混交林最好,梭梭纯林(6m×9m)最差;防风固沙林建立20年后,林内土壤粗粒沙(1.0~0.5mm)含量降低66.4%,而<0.25mm的细沙和粉(黏)沙含量由12.8%提高至72.0%,土壤有机质含量提高30.1%,土壤全N增加48.3%,全P增加76.3%,全K增加58.0%,土壤pH值和全盐量均有降低。20年来防风固沙林的防风固沙效益和改土作用显著。     

不同隔盐材料对滨海盐渍土水盐动态和树木生长的影响

[目的]揭示不同隔盐材料对滨海盐渍土水盐动态和树木生长的影响,为滨海地区盐渍土改良和沿海防护林营造等林业工程提供理论依据。[方法]采用单因素方差分析及多重比较方法,于2010—2013年在天津滨海重度盐碱地区的大田试验中,开展了沸石、陶粒、蛭石和河沙4种隔盐材料对盐渍土0—80cm土层水盐动态及4个树种(刺槐、国槐、香花槐和红叶臭椿)生长影响的研究。[结果](1)在树穴底部和侧壁铺设隔盐层可以明显降低土壤含盐量并显著增加土壤含水量。沸石处理(FS)能显著降低0—80cm土体内盐分含量,控抑盐效果明显优于其他处理。陶粒处理(TL)在40—80cm土层有显著的降盐效果,但其控盐效果比沸石差。蛭石处理(ZS)仅在40—60cm土体内显著降低土壤含盐量。河沙处理(HS)中,0—80cm土体内盐分含量虽低于对照,但与对照之间无显著差异,降盐效果最差;(2)铺设隔盐层可显著降低土壤盐分离子含量,其中对Na+,Cl-和SO2-4这3种滨海盐碱地主要盐分离子的去除效果排序为:FSTLZSHS;(3)隔盐层材料能有效改善树种根区土壤物理性质,提高各树种成活率和保存率,并能明显促进植物生长,其中沸石效果最佳。[结论]可将沸石作为滨海地区4个树种造林时隔盐材料的最优选择。     

海岛地区小流域暴雨洪涝灾害模拟研究

[目的] 对海岛地区小流域暴雨洪涝灾害进行模拟研究，为该类地区后续开发建设以及防洪排涝治理工作的顺利开展提供技术支撑。[方法] 选取浙江省舟山市朱家尖岛为研究对象，根据设计暴雨及设计和校核潮位资料，运用MIKE构建了一维河网模型、二维水动力模型以及MIKE FLOOD耦合计算模型，对比分析两种方案的淹没面积和水深、典型河道断面水位以及重点区域洪水演进过程。[结果] 相对于设计暴雨及设计潮位条件下的方案1（94降雨+实测潮位），设计暴雨及校核潮位条件下的方案2（94降雨+极限潮位）在相对高水位时刻淹没面积更大，最大淹没深度更深。[结论] 朱家尖流域内河流比降大，汇流时间短，流域调蓄能力差，抵抗暴雨产生的洪涝灾害的能力较弱。特别是暴雨遭受天文大潮时，研究区域受灾程度更重。     

长武塬区沟坡开发中的水土保持和农业基础设施建设探讨

黄土高原沟壑区沟坡开发已是人们争取生存空间，缓和土地压力的途径，也是现阶段农村经济发展的基础。沟坡应的优化生态一半和改善农业生产条件的前提下进行开发。该以长武王东沟试验区为例，论述了沟坡开发中的水土保持和农业基础设施，即水、田、果、林、路五五项子工程的配套建设。     

基于GIS下的岷江干旱河谷地区泥石流发生域危险性评价

 四川省汶川县地处岷江上游,是我国泥石流频发地区。泥石流的发生与分布受地质构造、地貌条件、岩石种类、降水和植被等多种因素影响。以汶川县为例,在GIS技术支持下,通过计算机对空间数据获取、处理和分析,建立该地区泥石流发生域危险性评价指标体系及评价模型。通过合理选取评价指标、确定指标权重、计算综合评价值,得出:在该研究区域的16条沟系中,依据综合指数值,最易发生泥石流的沟系为桃关沟,佛堂坝沟等沟系,有潜在泥石流发生的沟系为新桥沟,板子沟等,而炭里沟,板桥沟等沟系属于无泥石流发生沟系。该评价结果经与历史资料对比和专家认可,符合实际,客观可行,可为防灾减灾、泥石流预报提供参考。     

延河流域2013年7月连续暴雨下淤地坝毁坏情况调查与评价

[目的]查明2013年7月延河流域连续出现的5次范围广,历时长,量级大的强降雨条件下淤地坝的运行及毁坏情况。[方法]对延河流域3县区15个小流域45座淤地坝进行实地考察。[结果]被调查淤地坝中35座经受住了暴雨洪水的袭击。遭毁坏的10座淤地坝中9座为已淤满变为耕地的"闷葫芦"坝(一大件)及1座新建坝。而尚未淤满正在发挥作用的淤地坝以及新旧结合的坝系大多数都正常运行。[结论]延河流域该次淤地坝毁坏的直接原因是高强度和持续集中降雨造成的超标准暴雨洪水,同时淤地坝在建设、运行和管理方面也存在诸多问题。     

Handling Sediments in Dutch River Management: The Planning Stage of the Maaswerken River Widening Project

Background, Aim and Scope   Faced with higher peak discharges in the foreseeable future, the Dutch government has decided to increase the discharge capacities of the Dutch Rhine and Meuse rivers. Instead of raising the dikes, river widening measures are to be undertaken, in and along the riverbed. Such measures include surface level lowering along the rivers, channel deepening, the addition of high-discharge channels and the removal of hydraulic obstacles. To cover or reduce the costs of river widening, a coupling with aggregates (sand and/or gravel) extraction has been considered. Although the rationale of this concept is basically sound, it has met with considerable resistance, especially along the southernmost stretch of the Dutch Meuse River, in the Maaswerken project area. Main Features: The Dutch river widening projects are quite unique in size and occurrence, and the number of publicly documented case histories available for the planning of such works is inevitably few. We review the planning and decision-making process for the Maaswerken project, which is in a more advanced stage than that of the corresponding project for the Rhine. Sediment handling and aggregates extraction are focused on, which are key issues to this case. Results: - Discussion: In the study area, there is a conflict of interests between the extractive industry and the local communities. The industry faces a policy of phasing out mineral extraction; river widening presents the last significant prospects in the area. The general public, however, has come to resent mineral extraction because of its historical impacts. Aiming at a manageable process, the Maaswerken project management kept most stakeholders in a basically reactive position: the general public was kept informed and enabled to submit formal reactions to draft planning decisions. Aggregate extraction plans and extraction volumes were only discussed with the industry. Despite not being represented, the public influenced this negotiation process by expressing dissatisfaction with interim outcomes through the media and political channels. Plans had to be reconsidered, and this closed process turned out to be only seemingly efficient. Conclusions: The level of public concern regarding the Maaswerken project suggests that the overall level of stakeholder involvement may have been insufficient, even though it complied with pertinent environmental and planning legislation. A participation deficit seems to have mainly occurred when defining the project's preconditions: a predefined, controversial role for the extractive industry was implicit in self-financed river widening. As planning and decision making in large projects such as the Maaswerken are prone to be affected by a negative public opinion, it is recommended that social feasibility is assessed and addressed at the very outset. Perspectives: -