高温高盐高黏油藏缔合聚合物-表面活性剂二元驱技术

针对大港油田孔南地区高温、高盐、中低渗、稠油等制约化学驱提高采收率的瓶颈技术问题,以官109 1断块枣Ⅴ油组为目标油藏,在优选适合缔合聚合物和表面活性剂基础上,进行聚合物-表面活性剂二元驱技术室内实验和现场应用研究。通过室内实验优选,缔合聚合物AP P7和表面活性剂BHS 01二元体系溶液与常规体系相比,具有较好的耐温抗盐性,拓展了常规二元驱适用油藏的温度和矿化度范围;缔合聚合物经过岩心剪切后仍能够有效建立阻力系数和残余阻力系数;通过岩心驱替实验,体系能有效提高稠油油藏的采收率,拓宽了聚合物驱适用的原油黏度范围;矿场单井试注后,注入井注入压力和启动压力升高,纵向吸水剖面得到改善,说明该体系在高温高盐条件下仍能保持较高黏度,能够有效改善水油流度比,效果明显。     

洞庭湖区与城陵矶水位关联性的临界特征分析

采用典型测站观测资料与水力学原理相结合,分析不同情况下城陵矶水位与洞庭湖区水位关联性强弱转化的机理和临界条件以及三峡水库对其影响等问题。理论解析表明,固定流量下,湖区水位与城陵矶水位相关关系应为单调指数函数,受到区间距离、湖槽形态等多因素影响,据此提出和率定了各湖区水位的经验计算模式。利用经验计算模式对实测数据进行延展,构建了各种可能出现的湖区来流和干流水位组合下的湖区水位特征曲线族,发现湖区水位与城陵矶水位之间的关联强度存在无影响区、影响区和决定区等状态区间,通过对临界条件的定义和计算,实现了各状态区间的定量划分,并提出了各状态区间内洞庭湖区水位的估算方法。通过对三峡水库蓄水后湖床冲淤和水文条件变化的影响分析,论证了以上方法和认识在水库蓄水后的适用性。     

溱湖湿地生态系统服务价值评估研究

利用实地调研结果,结合相关文献资料,采用市场价值法、影子工程法、旅行费用法等评估方法,对溱湖湿地生态系统的物质生产、涵养水源和调蓄洪水、提供动植物栖息地、调节气候、降解污染物和科考旅游等6个效益最为突出的生态系统服务功能经济价值指标进行评估。研究表明：溱湖湿地生态系统的总价值为1.15×109元,其中直接使用价值为7.708×108元,间接使用价值为3.62×108元,非使用价值为0.18×108元。其中科考旅游价值所占比重最大,为40.84％,调节气候价值次之,而生物多样性保护价值仅占1.45%。对溱湖湿地生态系统服务功能及服务价值的探讨,可正确认识该生态系统的生态经济价值,为合理开发利用提供决策参考,确保其资源的可持续利用。     

Toxic cyanobacteria at Nakuru sewage oxidation ponds - A potential threat to wildlife

Phytoplankton composition and biomass, and microcystin content were determined on diverse dates between November 2001 and June 2006 in the final oxidation pond of the Nakuru town sewage treatment plant. The oxidation ponds as well as the rivulet that drains the same are important water sources for some wildlife in the park. The phytoplankton composition of the pond studied mostly comprised coccoid green alga species. However, occasionally cyanobacteria or euglenoids were dominant. Among the cyanobacteria, Microcystis sp. made periodic appearance in the phytoplankton, and was the dominant species on some occasions. Total phytoplankton biomass varied widely from 48 to 135 mg L⁻¹ (wet weight) while cyanobacteria biomass ranged from undetectable levels to 130 mg L⁻¹. Most phytoplankton biomass was due to one or a few species. Detectable cyanotoxin concentrations (sum of microcystins) of up to 551.08 μg mg⁻¹ dry weight (DW) of cyanobacteria biomass or 0.28 μg mg⁻¹ DW of total phytoplankton biomass were recorded in samples collected on different dates. Microcystin content did not appear to correspond to the biomass of cyanobacteria suggesting that toxin production is possibly triggered by environmental changes or changes in the proportion of toxic strains. An occasional presence of microcystins in the pond water suggests that the wildlife species, which regularly use the ponds as drinking water sources are potentially exposed to intoxication. A close monitoring of pond water phytoplankton composition is necessary to accurately quantify the potential impact of cyanotoxins on these wildlife species.     

High accuracy measurements of water storage change in Mining Lake 111, Germany

Several pressure sensors were deployed in a small lake to determine its storage change. It could be shown that a deep enough deployment and an averaging over a time interval of 1 hour and 5 measuring points allowed for a measurement of 1 or 2 kg/m² (i.e. 2 mm of water column) of changes in the storage on the scale of the lake size. This accuracy for the lake storage could not be achieved by other methods, especially if conditions were difficult, e.g. snowfall, or in cases when precipitation was small. Finally, the pressure measurement - originally intended to roughly determine the water level - turned out to be a direct measurement of water mass in the lake, which was the proper magnitude for exchanges between atmosphere and lake. Hence the measurement of lake storage could become an interesting approach even for meteorological measurements, such as precipitation and evaporation on a water surface.     

Local variability of sedimentation rate in Lake Arendsee, Germany

We measured the thickness and the dry weight of recently deposited sediment along several transects across Lake Arendsee in order to quantify the sedimentation rate and its local variability. As a time marker, we used an artificial marl layer that was deposited by a remediation program in the year 1995. A portion of the sediment deposited during the year was transported from the littoral and the top of the submerged hills to the foot of the slope, where we found the greatest deposition. Within the same lake, the deposited sediment layer varied by a factor of 4 between minimal and maximal values over the same time periods. Lake Arendsee is a holomictic and eutrophic lake with depletion of oxygen in summer time.     

The history of water salinity in the Pearl River estuary,China, during the Late Quaternary

This research reconstructed the Late Quaternary salinity history of the Pearl River estuary, China, from diatom records of four sedimentary cores. The reconstruction was produced through the application of a diatom–salinity transfer function developed based on 77 modern surface sediment samples collected across the estuary from shallow marine environment to deltaic distributaries. The statistical analysis indicates that the majority of sediment samples from the cores has good modern analogues, thus the reconstructions are reliable. The reconstructed salinity history shows the older estuarine sequence formed during the last interglacial was deposited under similar salinity conditions to the younger estuarine sequence, which was formed during the present interglacial. Further analysis into the younger estuarine sequence reveals the interplays between sea level, monsoon‐driven freshwater discharge, and deltaic shoreline movement, key factors that have influenced water salinity in the estuary. In particular, a core from the delta plain shows the effects of sea‐level change and deltaic progradation, while cores from the mouth region of the estuary reveal changes of monsoon‐driven freshwater discharge. This study demonstrates the advantages of quantitative salinity reconstructions to improve the quality of reconstruction and allow direct comparison with other quantitative records and the instrumentally observed values of salinity. Copyright © 2010 John Wiley & Sons, Ltd.     

青海湖流域河川径流特征及其对降水的滞后效应

以青海湖流域的布哈河为例,采用变差系数、集中度和集中期等指标,对青海湖流域内径流量、降水量在年代、年际、季节等时间尺度上进行分析,并用集中期来反映河川径流对降水的滞后效应。结果显示,河川径流年内主要集中在6—10月,特别是7月中旬至8月中旬之间;降水主要集中在5—9月,特别是7月;径流量与降水量存在极大的相关性（r=0.746＞0.443=α0.001(47)）,径流对降水具有滞后效应,多年平均滞后时间为20 d左右。     

塔里木河下游表层土壤盐分空间变异和格局分析

土壤盐化是造成塔里木河下游天然植被退化的主要因素之一,应用地统计学方法,分析了塔里木河下游表层土壤盐分的空间异质性特征。结果表明,研究区土壤含盐量普遍较高,表层土壤盐分呈现强变异性和具有较强的空间自相关格局,主要受结构性因子影响。空间插值结果表明,表层土壤盐分整体上呈现出条带状的分布格局,局部地区表现出斑块状的空间变异特征。从河流纵向看,表层土壤盐分“两头高,中间低”;从河流横向看,离河道越远,盐分越低,地下水埋深逐渐加深,物种数和植被盖度分别表现出与之相应的递减趋势。     

“水资源域”概念在美国五大湖的应用(英文)

"水资源域"为在某一时段向河口或某一地点,传送水、水中营养物、泥沙或其它物质的空间范围。这一新概念与"流域"概念既相似又不同:1)流域边界以地貌特征来确定,相对稳定。而水资源域的边界以水文事件中的水和物质传播范围来确定,随时空而变化;2)流域强调给定空间范围内水和物质的时间分布,而水资源域强调水和物质随时间和空间二者相互变化的动态分布;3)水资源域综合考虑了不同尺度的时空即时变化对水资源及物质传播的影响。这一新概念应用遥感、空间分析、追踪及模拟技术分析流域空间模式与过程,为水资源探索、分析、模拟及预测提供了一种全新的方法与途径。该文以美国伊利湖茅密河为例,应用分布式大流域模型计算了水资源域的分布。