Ecosystem benefits from coastal habitats—A three-country choice experiment

Coastal habitats provide a variety of benefits for citizens living in littoral countries. The economic value of changes in coastal habitats in the context of the implementation of the Baltic Sea Action Plan, targeting good ecological status by 2021, in two coastal sites was estimated using the choice experiment method. The selected aspects of marine ecosystem were described in conjunction with ecological changes modeled within the Finnish–Swedish archipelago and the Lithuanian coast. The benefits for Finns, Swedes, and Lithuanians for changes in the adjacent coastal site were estimated with the conditional logit and random parameters logit models accounting for preference heterogeneity. The willingness to pay estimates for healthy perennial vegetation, protection of currently pristine areas, and size of fish stocks differed significantly between populations. The transfer errors ranging from 40%, when transferring the estimates for the same coastal site between populations, to 400%, when transferring between both sites and populations, underline careful consideration in value transfers.     

从南京市矿业经济构架概论矿业经济发展态势

从南京市的矿业经济成分入手,对矿山布局、加工水平、资源经济和社会效益等方面进行了分析,显示了乡镇矿业经济的发展情况.运用统计分析的结果说明南京市矿业经济总体特征和制约其发展的因素.提出了矿业经济发展的“矿山环境恶化变量“的概念以及与治理成本的关系,阐述了采矿活动对环境破坏与恢复治理的动态平衡原理.就OR值的优化也提出了相应的对策.运用宏观经济学等理论分析了区域性矿业经济发展的态势,围绕资源价值的加工放大能力产生的效益反哺环境治理的可行性进行了探讨.     

试论资源科学的发展与任务

归纳了资源的三类定义,回顾了资源概念中的时间尺度和价值理论问题,并对我国资源研究工作进行了总结,最后认为资源科学在２１世纪将会得到长足发展,为此需要开展１０个方面的研究工作,并应尽快使资源科学进入国家学科体系。     

沉积岩包裹体烃源条件时间温度指数判别法的探讨--以鄂尔多斯下古生界为例

包裹体在油气地质邻域的应用,是近年来包裹体研究的热点和难点。本文探索性地运用沉积岩中包裹体测试数据计算烃源岩主要生烃时期的时间温度指数(TTI),对沉积盆地的烃源条件进行判别。首先利用鄂尔多斯下古生界包裹体显微测温数据求取捕获温度、计算古地温梯度,得出动态古地温曲线;然后计算出下古生界烃源岩的门限。奥陶系烃源岩生烃门限时间为280～131Ma,相当于二叠纪至侏罗纪,其对应的生烃门限温度为70～115℃,门限深度2100～3400m,生烃高峰期为181.4～149.6Ma,相当于侏罗纪中晚期。在生烃高峰期该层位的温度为110～115℃,埋深3300～3400m。和实际主要产气层分布相一致,说明了应用沉积岩包裹体计算时间温度指数,对烃源条件进行判别这种方法的有效性。     

National height datum,the Gauss–Listing geoid level value w0 and its time variation 0 (Baltic Sea Level Project: epochs 1990.8, 1993.8, 1997.4)

 A methodology for precise determination of the fundamental geodetic parameter w ₀, the potential value of the Gauss–Listing geoid, as well as its time derivative ₀, is presented. The method is based on: (1) ellipsoidal harmonic expansion of the external gravitational field of the Earth to degree/order 360/360 (130 321 coefficients; http://www.uni-stuttgard.de/gi/research/ index.html projects) with respect to the International Reference Ellipsoid WGD2000, at the GPS positioned stations; and (2) ellipsoidal free-air gravity reduction of degree/order 360/360, based on orthometric heights of the GPS-positioned stations. The method has been numerically tested for the data of three GPS campaigns of the Baltic Sea Level project (epochs 1990.8,1993.4 and 1997.4). New w ₀ and ₀ values (w ₀=62 636 855.75 ± 0.21 m²/s², ₀=−0.0099±0.00079 m²/s² per year, w ₀/&γmacr;=6 379 781.502 m,₀/&γmacr;=1.0 mm/year, and &γmacr;= −9.81802523 m²/s²) for the test region (Baltic Sea) were obtained. As by-products of the main study, the following were also determined: (1) the high-resolution sea surface topography map for the Baltic Sea; (2) the most accurate regional geoid amongst four different regional Gauss–Listing geoids currently proposed for the Baltic Sea; and (3) the difference between the national height datums of countries around the Baltic Sea. Received: 14 August 2000 / Accepted: 19 June 2001     

Relationship between land cover and monsoon interannual variations in east Asia

Asian monsoon have multiple forms of variations such as seasonal variation, intra-seasonal variation, interannual variation, etc. The interannual variations have not only yearly variations but also variations among several years. In general, the yearly variations are described with winter temperature and summer precipitation, and the variations among several years are reflected by circulation of ENSO events. In this study, at first, we analyze the relationship between land cover and interannual monsoon variations represented by precipitation changes using Singular Value Decomposition method based on the time series precipitation data and 8km NOAA AVHRR NDVI data covering 1982 to 1993 in east Asia. Furthermore, after confirmation and reclassification of ENSO events which are recognized as the strong signal of several year monsoon variation, using the same time series NDVI data during 1982 to 1993 in east Asia, we make a Principle Component Analysis and analyzed the correlation of the 7th component eigenvectors and Southern Oscillation Index (SOI) that indicates the characteristic of ENSO events, and summed up the temporal-spatial distribution features of east Asian land cover’s inter-annual variations that are being driven by changes of ENSO events.     

东亚土地覆盖动态与季风气侯年际变化的关系

以东亚地区 １９８２～１９８９年时间序列降水资料及 ＡＶＨＲＲ ８ ｋｍ ＮＤＶＩ数据为基本数据源，应用地理信息系统技术，分别研究了东亚地区夏季（５－９月）降水及土地覆盖的年际变化，并揭示了研究时间段内各自的变化规律。进一步用奇异值分解（ＳＶＤ）模型方法分析了以降水变化为表征的东亚地区气候年际变化与土地覆盖年际变化之间的关系。     

依舒断裂带北段尾波Q值特征研究

研究表明,地震波穿过构造活动相对稳定地区时,能量衰减不明显且具有高Q值;而穿过构造活动地区时,能量会发生强烈衰减且具有低Q值。本文利用Sato模型对依舒断裂带北段萝北-通河地区15个数字化地震台站记录到的266条M_L≥2.0地震尾波Q_c值进行了分析和研究,发现黑龙江萝北、通河附近地区Q_c值具有明显的复杂性和差异性,且萝北地区Q_c值远低于通河地区Q_c值,其原因一方面与区域构造活动有关,另一方面与区域地壳构造复杂、地下介质破碎、区域应力不断变化有关。本文还讨论了萝北、通河附近地区Q值随着频率变化的关系及Q_0值空间分布特征,有效地分析了该区域介质状态的变化过程,对萝北地区地震活动性的研究和预测有指导意义。     

长岛震群b值随深度变化特征

利用双差定位方法对2017年2月~2018年5月长岛震群进行重定位, 根据重定位结果计算长岛震群地震集中活动区域b值在深度上的变化分布。 结果显示: 长岛震群重定位的结果主要表现为北、 南两个地震活动区域。 北部地震活动区域的地震数量多, 时间跨度长; 南部地震活动区域的地震数量较少, 形成时间较晚, 震源深度主要集中在地壳深度4~25 km之间; 长岛震群北、 南两个地震活动区域的b值总体上均随深度增大而减小, 在8.5 km深度左右均存在转折上升的情况。 长岛震群b值的深度变化特征表明, 其应力主要受围岩静压力影响, 受断裂活动影响较小。     

Image-domain wavefield tomography for tilted transversely isotropic media

Transversely isotropic models with a tilted symmetry axis have become standard for imaging beneath dipping shale formations and in active tectonic areas. Here, we develop a methodology of wave-equation-based image-domain tomography for acoustic tilted transversely isotropic media. We obtain the gradients of the objective function using an integral wave-equation operator based on a separable dispersion relation that takes the symmetry-axis tilt into account. In contrast to the more conventional differential solutions, the integral operator produces only the P-wavefield without shear-wave artefacts, which facilitates both imaging and velocity analysis. The model is parameterized by the P-wave zero-dip normal-moveout velocity, the Thomsen parameter δ, anellipticity coefficient η and the symmetry-axis tilt θ. Assuming that the symmetry axis is orthogonal to reflectors, we study the influence of parameter errors on energy focusing in extended (space-lag) common-image gathers. Distortions in the anellipticity coefficient η introduce weak linear defocusing regardless of reflector dip, whereas δ influences both the energy focusing and depth scale of the migrated section. These results, which are consistent with the properties of the P-wave time-domain reflection moveout in tilted transversely isotropic media, provide important insights for implementation of velocity model-building in the image-domain. Then the algorithm is tested on a modified anticline section of the BP 2007 benchmark model.