酸性矿山废水中生物成因次生高铁矿物的形成及环境工程意义

酸性矿山废水(acid mine drainage,AMD)是一类pH低并含有大量有毒金属元素的废水。AMD及受其影响的环境中次生高铁矿物类型主要包括羟基硫酸高铁矿物(如黄铁矾和施威特曼石等)和一些含水氧化铁矿物(如针铁矿和水铁矿等),而且这些矿物在不同条件下会发生相转变,如施氏矿物向针铁矿或黄铁矾矿物相转化。基于酸性环境中生物成因次生矿物的形成会"自然钝化"或"清除"废水中铁和有毒金属这一现象所获得的启示,提出利用这些矿物作为环境吸附材料去除地下水中砷,不但吸附量大(如施氏矿物对As的吸附可高达120mg/g),而且可直接吸附As(III),还几乎不受地下水中其他元素影响。利用AMD环境中羟基硫酸高铁矿物形成的原理,可将其应用于AMD石灰中和主动处理系统中,构成"强化微生物氧化诱导成矿-石灰中和"的联合主动处理系统,以提高AMD处理效果和降低石灰用量。利用微生物强化氧化与次生矿物晶体不断生长的原理构筑生物渗透性反应墙(PRB)并和石灰石渗透沟渠耦联,形成新型的AMD联合被动处理系统,这将有助于大幅度增加处理系统的寿命和处理效率。此外,文中还探讨了上述生物成因矿物形成在AMD和地下水处理方面应用的优点以及今后需要继续研究的问题。     

统一分布下的LP估计抗差测度

本文根据定位参数Ｍ估计理论,导出了ＬＰ估计的影响函数,分析了ＬＰ估计的抗差能力,同时还推导了ＬＰ估计的渐近效率,综合抗差能力和效率,分析了ＬＰ估计的优劣性,明确指出,用现测数据中含有粗差扰动的数据和Ｐ为（１,１．２５）的ＬＰ估计进行处理,结果较优,效率较高。     

Progress and Prospect of Statistics and Assessment of Large-scale Natural Disaster Damage and Losses

In June 2014, the "Statistics System for the Damage and Loss of Large-scale Natural Disasters" (SSDLLND) was issued by the Ministry of Civil Affairs and the Office of National Disaster Reduction Committee, which marked that the statistics and assessment of China's catastrophic natural disaster damage and losses formally entered a new stage of institutionalization. On the basis of analyzing the five major international disaster damage and loss assessment systems, including HAZUS-MH, ECLAC, DaLA, EMA-DLA and PDNA, the differences between the “SSDLLND” of China and five major international systems were compared from the statistics and assessment contents and indicators. Combined with the statistics and assessment practices of China’s large-scale disaster damage and losses and the characteristics of international systems in recent years, the future development of the SSDLLND were proposed in three aspects: Enriching and improving the framework of damage and loss statistics content, stepwise improvement of disaster impact assessment methods (such as the ecological capital loss assessment, tourism industry loss assessment due to the disasters, etc.), and improving indicators and parameters of loss statistics. The study has an important practical significance for improving the statistics and assessment system of the damage and loss of major natural disasters and better serving the post-disaster recovery and reconstruction decision-making.     

夯扩桩沉管控制贯入度计算法

通过改造格尔谢万诺夫打桩公式,提供了夯扩桩沉管控制贯入度计算表达式,在此 ,介绍了沉积控制贯入度在夯扩桩设计和施工中的用途,并举例验证。     

Possible sources of forecast errors generated by the global/regional assimilation and prediction system for landfalling tropical cyclones. Part I: Initial uncertainties

This paper investigates the possible sources of errors associated with tropical cyclone (TC) tracks forecasted using the Global/Regional Assimilation and Prediction System (GRAPES). The GRAPES forecasts were made for 16 landfalling TCs in the western North Pacific basin during the 2008 and 2009 seasons, with a forecast length of 72 hours, and using the default initial conditions (“initials”, hereafter), which are from the NCEP-FNL dataset, as well as ECMWF initials. The forecasts are compared with ECMWF forecasts. The results show that in most TCs, the GRAPES forecasts are improved when using the ECMWF initials compared with the default initials. Compared with the ECMWF initials, the default initials produce lower intensity TCs and a lower intensity subtropical high, but a higher intensity South Asia high and monsoon trough, as well as a higher temperature but lower specific humidity at the TC center. Replacement of the geopotential height and wind fields with the ECMWF initials in and around the TC center at the initial time was found to be the most efficient way to improve the forecasts. In addition, TCs that showed the greatest improvement in forecast accuracy usually had the largest initial uncertainties in TC intensity and were usually in the intensifying phase. The results demonstrate the importance of the initial intensity for TC track forecasts made using GRAPES, and indicate the model is better in describing the intensifying phase than the decaying phase of TCs. Finally, the limit of the improvement indicates that the model error associated with GRAPES forecasts may be the main cause of poor forecasts of landfalling TCs. Thus, further examinations of the model errors are required.     

星际甲醇（CH3OH）脉泽

简要综述了近年来对于星际ＣＨ３ＯＨ脉泽的观测和研究成果，对ＣＨ３ＯＨ脉泽的性质从分类，生成区域及分布，辐射特性，运动状况等方面做了介绍，并阐明了理论上对其时变特性，激发机制及河外脉泽的探讨，最后对两种类型的ＣＨ３ＯＨ脉泽作了对比和讨论。     

Nitrous oxide emissions from different land use patterns in a typical karst region, Southwest China

Fluxes of nitrous oxide (N2O) from different land use patterns (matured forest, secondary forest, grassland and cropland) in a subtropical karst region of Guizhou Province, Southwest China, were measured for one year with a closed static chamber technique and by gas chromatography. The results showed that soil under different land uses was a source of atmospheric N2O. The cropland was a source with relatively high N2O as compared to forest and grassland, but no significant differences were observed. N2O emissions from soils varied with land use change and fertilizer application. There were two peaks of N2O flux occurred following the combination of two obvious precipitation and fertilizer events in the cultivated land. Converting from the matured forest to secondary forest tended to increase annual emissions of N2O (from 1.40 to 1.65 kg N ha -1 a -1 ), while changing land use from secondary forest to scattered grassland tended to decrease annual emissions of N2O slightly (from 1.65 to 1.45 kg N ha -1 a -1 ). Our range of cumulative annual N2O emission across different land uses (1.40-1.91 kg N ha -1 a -1 ) in a karst region is in general agreement with previously published data in a non-karst region. However, in the maize field, N2O emission factor (EF) was 0.34% for fertilizer application, which is about 71.2% lower than the IPCC default value. It is suggested that current IPCC (Intergovernmental Panel on Climate Change) EF methodology could overestimate N2O emission from the karstic cropland. Anyway, the N2O emission from cropland in the karst region would contribute significantly to the global N2O budget, so reducing fertilization frequency during the crop growing season could lead to a decrease in N2O emission in the whole year.     

南沙群岛海域构造地层及构造运动

根据对“实验2”号调查船1987—1991年测得的反射地震剖面的解释,论述了南沙群岛海域的构造层划分、时代属性与分布发育特征。提出本区自白垩纪中期以来发生过两次重大的构造运动,形成两个裂谷作用构造旋回。     

Vertical tilt structure of East Asian trough and its interannual variation mechanism in boreal winter

Vertical tilt structure of the East Asian trough (EAT) and its interannual variation mechanism in boreal winter are studied using NCEP/NCAR, ERA40, and NCEP/DOE reanalyses. A vertical tilt index (VTI) is defined as the mean slope of vertical trough line on the longitude-height cross section to describe the tilting extent of the EAT, with high index indicating a more west-tilted trough and vice versa. The VTI series derived from the three reanalysis datasets are highly correlated with each other during the corresponding periods. A significant positive correlation is found between the VTI and the zonal range of the vertical trough line. Based on the close relation, a possible physical mechanism is proposed to explain the interannual variation of VTI. It demonstrates that positive (negative) temperature anomalies within the mean zonal range of the EAT result in expansion (contraction) of the zonal range and lead to high (low) VTI years. The composite analyses based on the three reanalysis datasets well support the proposed mechanism. Furthermore, the general relationship between the VTI and the zonal temperature gradient is discussed based on the proposed mechanism. It is revealed that the asymmetric change of temperature gradient on the western and eastern sides of the EAT plays an important role in the variation of VTI, which suggests that the tilting extent of the EAT is strongly affected by the two-order zonal change of temperature instead of the zonal temperature gradient (i.e., one-order change). Climate variability not only in the simultaneous winter but also in the following spring and summer over East Asia is closely related to the variation of the VTI. This study on the vertical tilting of the EAT may enrich knowledge of the East Asian winter monsoon and the climate variability over East Asia and may be helpful in improving the regional climate prediction in East Asia.     

基于空间计量模型的中国城市化发展与城市空气质量关系

采用中国289个地级及以上城市2016年的空气质量指数（AQI）和夜间灯光数据,运用空间滞后模型,从空间溢出效应视角出发探究了城市化发展与空气质量之间的定量关系。从空间滞后模型的估计结果来看,城市空气污染存在显著的空间溢出效应,周边地区空气质量的下降会导致本地空气污染情况加重。在城市发展过程中,城市经济发展水平的提高,引致的城市建设用地的扩张使得空气质量不断恶化;政府管制力的加强对空气污染的治理起到了促进作用,而居民环保意识和城市技术创新水平的提高有利于空气质量的改善。此外,PM2.5质量浓度的上升导致空气质量恶化。公路货运量在统计上与空气质量的关系不显著。从研究结果来看,协调城市发展与空气质量的关系以及加强空气污染防治的联防联控机制,是未来空气污染治理工作的重点。