杭州西溪湿地生态旅游开发现状与前景初探

湿地生态旅游是基于丰富的湿地生态旅游资源发生的多种形式的旅游活动,它可以实现旅游者回归自然、体验传统文化和民俗风情、保护湿地生态环境的愿望。在实地调查和资料分析的基础上,文章总结了西溪湿地生态旅游的现状和存在的问题,探讨了该地生态旅游开发的优势及前景,并就杭州西溪湿地生态旅游开发模式、湿地生态环境及资源保护等提出建议。     

胶州湾沉积物重金属形态不同浸取方法的比较与污染讯息指示作用初探

海洋沉积物中重金属的活性形态对于指示沉积物污染状况具有重要作用;为探寻简洁且能够有效提取重金属活性形态的浸提方法;实验研究了0.1 mol/L和1 mol/L盐酸的单级提取和欧共体标准局（European Community Bureau of Reference）提出的BCR分级提取法对胶州湾表层沉积物中重金属（Cr、Cu、Ni、Pb、Zn）和Al、Fe、Mn的浸取效果。结果显示;3种提取方法提取的金属含量呈显著正相关关系;两种浓度的稀盐酸对BCR方法中的酸可提取态和可还原态金属均具有较好浸提效果;但对可氧化态金属浸提能力相对较弱。不同提取方法的人为信号指数（ASI）计算结果表明;BCR浸取法提取结果的金属ASI值最大;表明其对沉积物中金属活性形态提取效率较高;1 mol/L HCl提取结果的金属ASI值最低;可能是较高浓度强酸使沉积物较大颗粒内层中“惰性”金属被浸取出来;“增加”了金属活性组分的污染讯息信号;对沉积物中Cu、Pb和Zn而言;0.1 mol/L HCl提取结果的ASI值与BCR方法接近。经过Al归一化后;0.1 mol/L HCl浸提的重金属含量的空间分布与胶州湾的实际污染状况相吻合;表明0.1 mol/L的HCl在一定程度上能够代替复杂的BCR浸取法;此方法可简化重金属活性形态的提取步骤;适合大范围沉积物重金属污染评价。     

南极低温降解菌Shewanella sp. NJ49羟化酶分离纯化及最适产酶条件研究

羟化酶是细菌降解烷烃的关键酶,本文以南极低温降解菌Shewanella sp.NJ49为研究对象,通过硫酸铵沉淀、超滤浓缩及葡聚糖凝胶Sephadex G-75柱层析方法,分离纯化NJ49的羟化酶,获得了单一羟化酶组分,研究了温度、p H、表面活性剂和盐度等环境因素对NJ49羟化酶酶活活性影响。结果表明,羟化酶组分由α、β、γ三个亚基组成,分子质量分别为56,45和36 k D。NJ49最适产酶条件为:温度15℃、p H7.2、盐度55;不同类型表面活性剂对酶的活性影响效应不一,两性离子表面活性剂、阳离子表面活性剂、非离子表面活性剂对酶活没有作用,阴离子表面活性剂+非离子表面活性剂混和剂和阳离子表面活性剂+非离子表面活性剂混和剂能提高羟化酶的活性。     

琼东南盆地深水区松南-宝岛凹陷反转构造带发育特征及油气地质意义

利用新三维地震资料对松南-宝岛凹陷反转构造带发育特征、形成期次进行研究,并从构造背景及力学机制两个方面探讨反转构造的成因机制。研究结果表明,松南-宝岛凹陷反转构造带主要发育一系列"上凸下凹"的大型褶皱背斜,伴生NWW向弱走滑断裂构造和NNW向张剪构造。反转构造及其伴生构造符合NEE右旋剪切应力场特征,形成时间与东沙运动一致,表明该反转构造带可能受晚中新世南海东北部东沙运动产生的右旋走滑应力场作用控制。反转构造有利于研究区圈闭的重建和改造,对琼东南盆地东部新区油气运移和重新优选分配的认识,具有重要的油气地质意义。     

Effect of thickness of planar nozzles on erosion depth of levee soils subjected to plunging water

In this study, the effect of the thickness of a planar jet on the erosion depth when the jet impinges on a surface composed of cohesive soil was analytically and numerically evaluated. The results showed that the erosion depth was practically independent of the nozzle thickness for erosion depths shallower than the potential core length (i.e. the region of the jet in which the central flow velocity is the same as the nozzle velocity). The relation between nozzle thickness and erosion depth was non-linear with continuously variable slope for erosion depths deeper than the potential core length. Finally, the relation was approximately linear when the erosion depth converged to the equilibrium erosion depth. The findings of this study indicate that direct and fast prediction of the erosion depth in the field is possible using the data from a small scale soil erosion test with similar flow velocities.     

地震反演驱动的改进匹配追踪煤层识别方法

多类型油气藏储层受到煤层反射干扰, 有效识别与去除煤层地震响应是提高煤系储层地震描述精度的关键技术之一.常规煤层匹配识别欠缺考虑煤层弹性参数的影响, 引起煤层定位不准确、识别可靠性低、运算效率低等问题, 本文充分考虑了弹性参数对煤层具有较好的指示作用, 首次提出了地震反演驱动的改进匹配追踪煤层识别方法.首先根据岩石物理分析, 构建煤层指示因子, 提出匹配追踪煤层指示参数的地震反演方法, 该参数能够较好地刻画煤层空间展布; 基于此, 在地震反演驱动下获得了煤层的先验位置, 将其引入匹配追踪算法中约束匹配追踪搜索邻域, 为缓解现有匹配追踪算法运行效率缓慢, 将经验模态分解(EMD)引入匹配追踪领域, 同时将连续相位替换瞬时相位加快匹配追踪运算效率, 研发了煤层指示因子约束下基于EMD字典的改进匹配追踪煤层识别算法.模型测试验证了本文方法识别煤层的可行性, 实际资料的计算结果表明, 该方法在保持精度的情况下大大提高了计算效率, 此外, 预测的煤层与实际测井解释的煤层基本一致, 有助于油气储层预测和识别, 具有重要的实际应用价值.

     

贝塞尔曲线在虚拟森林景观单树几何模型构建中的应用

虚拟景观模型的生成,需要对实际景观进行抽象和简化。树几何模型和数字高程模型(DEM)是构成虚拟森林景观的两大要素。而树几何模型的构建又是林业GIS三维可视化的基础。在树几何建模中,树干及树枝形状的可视化表达具有突出意义。由于实际树种的复杂性,在计算机中建树模型,通常采用基于过程建模的方式,而这将面临用户如何对模型进行交互式控制的问题：参数太少,不足以描述树形态特征,而参数太多,则模型难以生成和理解。为了解决这个问题,我们引进贝塞尔(Bezier)曲线这种基于控制点的自由曲线来描述树木中的树干以及树枝形状,利用对曲线控制点的变动来控制曲线的形状,进而生成形态各异的树形状,对此,我们基于ActiveX技术生成Bezier曲线控件。结果表明,该方法能够表示多种形状的树干与树枝,具有操作简捷、计算速度快,可视化效果良好的优点。     

云南鲁甸6.5级地震灾害特点浅析

通过对2014年8月3日云南鲁甸6.5级地震震害开展实地调查,对灾区破坏情况进行总体介绍,并就各烈度区特征和建筑物震害、地震地质灾害、工程结构震害进行分析,初步得出本次地震的一些震害特点.一是灾区人口密度大,人员死亡较集中.人员死亡主要集中在Ⅷ和Ⅸ度区.二是地震振动强,灾区破坏严重.本次地震震源深度12km,极震区烈度高达Ⅸ度,震源破裂在11s内集中释放.三是抗震能力弱,房屋破坏严重.灾区属国家级贫困区,农村民居抗震能力弱,且多数民房坐落在河谷陡坡上,边坡效应加重房屋震害,重灾区砖木和土木房屋成片损毁、倒塌.四是灾区条件恶劣,救灾难度大.震区活动断裂密集发育、地质破碎疏松、地形崎岖不平,又恰值雨季,诱发极其严重次生地质灾害,导致人员伤亡,造成灾区大面积交通、通信、电力中断,救援物资与救援力量无法及时发挥作用.     

大别山东北缘构造片麻岩中锆石U-Pb年代学分析及构造意义

大别造山带是由华北板块和扬子板块经过长期构造演化、最终碰撞拼合的产物。大别山东北缘发育地壳深部构造层次上的构造片麻岩,通过对构造片麻岩的应力场恢复,认为大别山东北缘主要受到NE-SW向的特提斯构造体制和NW-SE向的太平洋构造体制两个体制的作用,并不是受单一的构造体制控制。锆石LA-ICP-MS微区U-Pb同位素测年结果显示,大别山东北缘至少存在3期构造事件。第一期是750±50 Ma的岩浆活动;第二期是210±10 Ma的变质活动;第三期是130±5 Ma的岩浆活动。大别山在碰撞造山后期发生了近水平东西向沿造山带的塑形流变,导致大别山中片麻理和线理走向均为NWW-SEE向,大别造山带发生塑形流变的时间在210±10 Ma左右,大概在195±5 Ma左右郯庐断裂带开始活动,改造了大别山原有的NWW-SEE向构造,使得大别山东端片麻理走向出现NE向转变。     

Carbon pools and fluxes in the China Seas and adjacent oceans

The China Seas include the South China Sea, East China Sea, Yellow Sea, and Bohai Sea. Located off the Northwestern Pacific margin, covering 4700000 km~2 from tropical to northern temperate zones, and including a variety of continental margins/basins and depths, the China Seas provide typical cases for carbon budget studies. The South China Sea being a deep basin and part of the Western Pacific Warm Pool is characterized by oceanic features; the East China Sea with a wide continental shelf, enormous terrestrial discharges and open margins to the West Pacific, is featured by strong cross-shelf materials transport; the Yellow Sea is featured by the confluence of cold and warm waters; and the Bohai Sea is a shallow semiclosed gulf with strong impacts of human activities. Three large rivers, the Yangtze River, Yellow River, and Pearl River, flow into the East China Sea, the Bohai Sea, and the South China Sea, respectively. The Kuroshio Current at the outer margin of the Chinese continental shelf is one of the two major western boundary currents of the world oceans and its strength and position directly affect the regional climate of China. These characteristics make the China Seas a typical case of marginal seas to study carbon storage and fluxes. This paper systematically analyzes the literature data on the carbon pools and fluxes of the Bohai Sea,Yellow Sea, East China Sea, and South China Sea, including different interfaces(land-sea, sea-air, sediment-water, and marginal sea-open ocean) and different ecosystems(mangroves, wetland, seagrass beds, macroalgae mariculture, coral reefs, euphotic zones, and water column). Among the four seas, the Bohai Sea and South China Sea are acting as CO_2 sources, releasing about0.22 and 13.86–33.60 Tg C yr~(-1) into the atmosphere, respectively, whereas the Yellow Sea and East China Sea are acting as carbon sinks, absorbing about 1.15 and 6.92–23.30 Tg C yr~(-1) of atmospheric CO_2, respectively. Overall, if only the CO_2 exchange at the sea-air interface is considered, the Chinese marginal seas appear to be a source of atmospheric CO_2, with a net release of 6.01–9.33 Tg C yr~(-1), mainly from the inputs of rivers and adjacent oceans. The riverine dissolved inorganic carbon (DIC) input into the Bohai Sea and Yellow Sea, East China Sea, and South China Sea are 5.04, 14.60, and 40.14 Tg C yr~(-1),respectively. The DIC input from adjacent oceans is as high as 144.81 Tg C yr~(-1), significantly exceeding the carbon released from the seas to the atmosphere. In terms of output, the depositional fluxes of organic carbon in the Bohai Sea, Yellow Sea, East China Sea, and South China Sea are 2.00, 3.60, 7.40, and 5.92 Tg C yr~(-1), respectively. The fluxes of organic carbon from the East China Sea and South China Sea to the adjacent oceans are 15.25–36.70 and 43.93 Tg C yr~(-1), respectively. The annual carbon storage of mangroves, wetlands, and seagrass in Chinese coastal waters is 0.36–1.75 Tg C yr~(-1), with a dissolved organic carbon(DOC) output from seagrass beds of up to 0.59 Tg C yr~(-1). Removable organic carbon flux by Chinese macroalgae mariculture account for 0.68 Tg C yr~(-1) and the associated POC depositional and DOC releasing fluxes are 0.14 and 0.82 Tg C yr~(-1), respectively. Thus, in total, the annual output of organic carbon, which is mainly DOC, in the China Seas is 81.72–104.56 Tg C yr~(-1). The DOC efflux from the East China Sea to the adjacent oceans is 15.00–35.00 Tg C yr~(-1). The DOC efflux from the South China Sea is 31.39 Tg C yr~(-1). Although the marginal China Seas seem to be a source of atmospheric CO_2 based on the CO_2 flux at the sea-air interface, the combined effects of the riverine input in the area, oceanic input, depositional export,and microbial carbon pump(DOC conversion and output) indicate that the China Seas represent an important carbon storage area.