氯与硫酸根比值对硫酸盐渍土工程性质影响的研究

对含氯化钠硫酸盐渍土的盐胀量，液限，塑限进行了试验分析，提出了不同硫酸钠含量水平下氯与硫酸根比值，即Ｃｌ＾－／ＳＯ４＾２－与盐胀率，Ｃｌ＾－／ＳＯ４＾２－与液限、塑限之间的计算公式，对从Ｃｌ＾－／ＳＯ４＾２－角度评判盐渍土的工程性质具有一定参考意义。     

新疆库车西部古近系奥奇克盐底辟地质地貌特征及构造形成模式

库车前陆冲断带西部古近系奥奇克盐底辟是中国最典型的盐底辟构造,可作为盐构造研究的天然实验室.本文在前人研究的基础上,通过详细的野外填图,同时辅以遥感解译、地震解释和合成孔径雷达干涉测量(InSAR)技术,探讨了奥奇克盐底辟盐喀斯特地貌特征,并分析了其形成机制及流变模式.奥奇克盐底辟表面盐喀斯特构造发育,在风化面上可见大...     

高纯度石英的酸浸实验研究

针对脉石英矿中含有大量云母及长石等伴生矿的特点，通过调整溶液浓度及温度等手段，强化矿物的酸浸效果。根据石英与杂质矿物在酸浸过程中的差异，探索消除石英中杂质矿物的方法。研究表明石英原料粉在温度为120℃、HF酸与水的比为0．4～0．5的溶液中酸浸适当时间后，其纯度可达到中高档石英玻璃的技术要求。     

金坛盐岩储气库运营模型试验研究

针对盐岩重度低、低弹强比、高流变性等强度与变形特性,研制出与金坛盐矿盐岩的力学行为较为相似的材料配方;采用地质力学模型试验技术,开展金坛盐岩储气库运行稳定性的模拟试验,研究腔体在周期性注、采气作用下的变形特点与力学分布规律。根据模型试验结果,采用盐岩非线性蠕变损伤本构模型,结合金坛盐岩储气库长期运营进行数值模拟,并与物理模型试验结果进行对比,研究分析储气库围岩在循环加卸载下的力学响应特点与盐岩溶腔的长期运营稳定性,得到了在周期性加卸载作用下腔体围岩蠕变变形的特点与规律,研究表明相似模型试验技术可以有效地应用于盐岩储气库运营长期稳定性的研究,其结果对盐岩储气库的建造与运行具有一定的指导意义和工程应用价值。     

盐胁迫对爪哇伪枝藻(Scytonema javanicum)生理生化特性的影响

研究了盐胁迫对荒漠生物结皮中的先锋藻类———S.javanicum的生理生化特性的影响。S.javanicum对盐胁迫很敏感,在较低盐浓度时光合作用活性已很低;色素分析表明,盐胁迫对类胡萝卜素的吸收值影响较大,对Scytonemin色素则较小。从对数生长期开始,其胞外总糖、胞外聚合物(Extracellularpolymericsubstance,EPS)和蛋白质浓度增高,并在稳定期和衰亡期达到最大。随盐浓度升高,盐胁迫显著抑制其生长,生物量产量下降,但单位生物量(μgChla)胞外聚合物各组份的产量增加,其中蛋白质的含量增加更显著。胞内还原性糖含量随盐浓度升高而升高,并在0.1mol·L-1时达最大;脯氨酸含量则呈V形变化。盐胁迫下胞外聚合物、胞内蔗糖、水溶性糖和还原性糖的大量积累,改变了胞内外物质浓度,说明糖类通过改变其代谢方式,在渗透调节上起着重要的作用。     

滴灌条件下盐地碱蓬(Suaeda salsa）种植年限对盐碱地土壤盐分离子分布的影响

采用时空转化的方法研究了滴灌条件下不同盐地碱蓬种植年限（0 a、1 a、2 a和3 a）对重度盐碱地土壤盐分及盐离子在0~120 cm土壤剖面的分布特征的影响,为盐地碱蓬在盐碱地中的改良利用提供理论依据。试验结果表明：滴灌种植盐地碱蓬后土壤盐分在剖面的分布发生明显变化,根区（0~40 cm）土壤含盐量随种植年限增加而下降,根底（40~120 cm）土壤则先增加后下降;Na⁺和Cl^-因容易被水淋洗和植物选择性吸收多,根区土壤中Na⁺和Cl^-含量随种植年限增加有显著降低,Ca²⁺和SO₄^2-不易随水移动,淋洗程度低,HCO₃^-和Mg²⁺第2 a和第3 a的淋洗效果明显好于第1 a;经过3 a种植后土壤中毒害离子Na⁺与Cl^-和在表层盐分组成中的比例下降,Ca²⁺比例上升,钠吸附比（SAR）值显著降低。     

囊谦盆地贡觉组含膏盐地层粘土矿物组合特征及气候环境意义

囊谦盆地晚始新世贡觉组厚层红色含膏盐粉砂质泥岩是研究青藏高原始新世古气候演化和含膏盐沉积环境的良好素材。采集囊谦盆地贡觉组约257 m含膏盐地层的碎屑沉积物,研究其粘土矿物成分和组合特征及气候与沉积环境变化。结果显示,粘土矿物主要以伊利石(52.1%)为主,其次为绿泥石(8.1%)和高岭石(3.5%)。根据岩性特征及粘土矿物组合变化,剖面自下而上可划分为3个阶段,分别指示了暖湿—低盐度、冷干—高盐度、较暖湿—低盐度的气候和沉积环境。贡觉组气候与沉积环境受到青藏高原地区干湿交替变化大背景的影响。     

Response of a hypersaline salt marsh to a large flood and rainfall event along the west coast of southern Africa

The Orange Estuary lost 27% (276 ha) of its wetland area near the mouth as a result of bad management practices during the 1980s. The salt marsh has been unable to recover over the last 20 years because of the persistently high soil and groundwater salinity. In 2006, a 1 in 5 year flood occurred that completely covered the desertified salt marsh and floodplain with freshwater. The flood was followed by an above average (>45 mm) winter rainfall. Soil and groundwater sampled in April and August 2004 were compared with 2006 data to quantify the impact of the flood and rainfall event. It was hypothesised that the two freshwater events would significantly reduce the soil and groundwater salinity. However, the results showed no significant difference in sediment electrical conductivity throughout the soil profile over the four sampling periods. Soil moisture and organic content however increased significantly after these events in the surface soil layer. The flood deposited silt and scoured sand from the surface layers in significant quantities. The depth to groundwater in the desertified marsh retained a similar pattern after the flood despite 15 cm changes in depth in places. In 2004 a clear groundwater electrical conductivity gradient was present extending from the less saline north part of the marsh (0–15 mS cm⁻¹) to the central part (120–135 mS cm⁻¹) and decreasing again towards the south (60–75 mS cm⁻¹). The flood served to even out the groundwater salinity across the desertified marsh (60–90 mS cm⁻¹). The flood and high rainfall had a limited impact on the soil and groundwater characteristics. The few significant changes that were recorded were mostly restricted to the surface soil layers and on a small spatial scale. The rainfall did however create numerous pools of low salinity (<60 mS cm⁻¹) water on the marsh surface that provided a brief opportunity for salt marsh seeds to germinate. A further benefit of the flood was the increased tidal reach into the desertified marsh importing freshwater from the river mouth and exporting salt. Despite these responses it is unlikely that the hypersaline salt marsh will revegetate naturally. Human intervention is needed to ensure the rehabilitation of this important Ramsar site.     

Cross-shore suspended sediment flux in the salt marsh pioneer zone of Chongming eastern beach in the Changjiang Estuary in China

Between April 2002 and April 2003, in situ measurements of water depth, current velocity and suspended sediment content were carried out in edge region of East Chongming salt marsh and neighboring bald flat in the Changjiang (Yangtze) Estuary under different weather conditions. Cross-shore suspended sediment flux was calculated and analyzed. The results show that under calm weather conditions, the current velocity process in bald field and salt marsh area varied differently during semidiurnal tidal cycles. Owing to current velocity asymmetry, mean SSC during flood tide phase was 1.8 times higher than that of ebb tide phase. As a result, net onshore sediment flux controlled cross-shore suspended sediment transport process and salt marsh pioneer zone was generally accreting. There was significant positive correlation between total sediment flux and quartic power of maximum water depth. It indicates that tidal ranges dominate suspended sediment transport and sedimentation process in the salt marsh pioneer zone under the calm weather condition. The sedimentation rate on the adjacent mudflat was higher than the salt marsh, which induced stable accreting of salt marsh towards the sea. The wind events enhanced SSC and current velocity during the semidiurnal tides. And the remarkable onshore net sediment flux could occur on the high marsh and mudflat close to the marsh fringe during the short period under the rough weather condition.     

潮滩围垦对海岸环境的影响研究进展

潮滩围垦是沿海国家拓展陆域, 缓解人地矛盾的最主要方式之一。潮滩围垦通过对潮滩高 程、水沙动力条件、沉积物特征等多种环境因子的改变, 促进生物演替, 并通过垦区土地的人为利 用, 对海岸环境演变产生重要影响。文章从围垦工程对水沙环境的影响、围垦对海岸带物质循环 的影响、围垦对潮滩生物生态学的影响和盐沼恢复与生态重建等4 方面探讨了不同学科学者对 围垦环境影响的主要研究进展及存在的问题, 并指出应加强多学科合作的综合研究, 探讨潮滩围 垦对海岸环境的影响机制, 以寻求兼顾围垦土地需求与海岸带生态保护的持续发展之路。