Sulphur-oxidising bacteria isolated from deep caves improve the removal of arsenic from contaminated harbour sediments

Acidophilic S-oxidising bacteria isolated from sulphur-rich deep caves (Frasassi, Italy), characterised by relatively low temperature, were tested for their ability to mobilise (semi-)metals from contaminated sediments. Sediment samples from two commercial Italian seaports were used to set up bioleaching experiments. The effect of different growth substrates was also investigated. Our experiments revealed that S-oxidising bacteria isolated from Frasassi caves have a high potential to remove As from contaminated marine sediments, as never reported before. Although As solubilisation efficiency was quite low (i.e. about 30%), only a small amount of As was associated with non-residual fractions of the sediment. On the contrary, the solubilisation efficiencies of Zn and Ni (20% and 10%, respectively) were lower than those previously obtained by the use of other acidophilic bacteria and mainly influenced by the experimental conditions rather than by the presence of the S-oxidising bacteria. Results presented here open new perspectives in bioleaching applications for the remediation of contaminated sediments. Indeed, microbial strains adapted to relatively low-temperature environments could improve sediment bioleaching at temperature regimes where mesophilic and thermophilic strains are not favoured. Such strains could be exploited for developing selective bioremediation procedures for sediments contaminated with As, to be applied in multistep biotreatment processes.     

大流量高流速溶洞堵漏技术的研究

在岩溶地区的各种工程的施工中,大流量、高流速溶洞的堵漏处理是一大难题。文章介绍了溶洞精确探测技术、堵漏材料、施工工艺上的最新研究成果,并以贵州猫跳河四级窄巷口水电站水库渗漏、贵州三岔河引子渡水电站厂房基坑涌水的处理为实例,介绍了孔间CT精确探测、模袋灌浆等技术的成功应用经验。     

安庆地震台山洞再利用的可行性研究

本文全面总结了安庆台山洞的现状,客观指出安庆台山洞巳经不能满足现实需求,并依据地震监测规范要求,就如何改善和解决观测条件和观测系统等方面存在的问题,以实现山洞的再利用进行了深入研究和探讨,认为安庆台山洞可以通过观测环境的改造、观测系统的升级等措施实现山洞再利用,并能够重新发挥安庆台洞体观测在全省地震监测中的重要作用,同...     

鸡冠洞CO2和222Rn变化特征以及与旅游活动关系研究

洞穴空气CO_2和~(222)Rn是岩溶洞穴中重要的小气候参数,理解影响洞穴空气CO_2和~(222)Rn浓度的时空变化特征及控制因素,对合理开发洞穴旅游资源有一定现实意义。本文通过2011年12月至2019年4月对我国南北气候过渡带附近河南省栾川县鸡冠洞空气CO_2和~(222)Rn浓度的多时空尺度的变化特征进行监测研究,主要得到以下结论:(1)在空间变化上,洞穴空气中的CO_2和~(222)Rn浓度主要受洞穴结构和通风效应的影响。越往洞内,CO_2和~(222)Rn浓度越大。(2)洞穴空气中的CO_2和~(222)Rn浓度季节变化特征明显,雨季上升,旱季下降,都受洞外水热环境的影响。鸡冠洞CO_2浓度变化范围为307～4 678 mg/L,受游客旅游活动的影响较为显著,空气~(222)Rn浓度变化范围为33. 0～2 421. 2 Bq/m~3,主要受洞穴结构和通风作用的影响。(3)在昼夜尺度的变化上,洞穴空气CO_2白天上升,夜间下降,主要受旅游活动的影响。空气中的~(222)Rn浓度与旅游活动的关系不明显。(4)鸡冠洞內吸入氡子体所导致的內照射人均年有效剂量为29. 6 mSv/a,虽然氡子体对一般游客产生危害较小,但年累积量需考虑,尤其是鸡冠洞内一线导游的核辐射安全防护。     

寿昌江流域及邻近山区溶岩洞穴大型水生底栖动物

灵栖洞、灵山洞、瑶琳洞为浙江西部山区已开发的著名观光溶岩洞穴群，灵栖洞位于寿昌江流域支流小江溪的源头附近，由灵泉、清风、霭云三洞组成，灵山洞由清虚洞、仙桥洞组成．三洞穴群内大型水生动物隶属2门3纲5目11科．灵栖洞大型水生动物群落主要由放逸短沟蜷和掌指米虾组成，灵山洞主要由硬环棱螺、放逸短沟蜷、格氏短沟蜷及水生昆虫幼体组成，瑶琳洞内主要由锯齿新米虾和扁卷螺组成．灵泉洞洞穴有光带主要分布有掌指米虾和放逸短沟蜷，弱光带主要分布有锯齿新米虾、掌指米虾和硬环棱螺，黑暗带主要分布有锯齿新米虾、掌指米虾和扁卷螺，灵泉洞有光带动物种类的多样性、均匀度指数最高，分别为0．9832和0．6109，黑暗带最低，分别为0．0983和0．1418；优势度在黑暗带最高，其值为0．6250．表3参18     

贵州纳朵洞洞穴水水文地球化学变化特征及其环境意义

对贵州关岭纳朵洞2012年12月至2014年12月期间,三处滴水(S1、S2、S3)和一处池水(SC)的地球化学指标进行动态监测.结合当地气象资料,分析了观测期间纳朵洞洞穴水水文地球化学季节变化及其对外界气候变化的响应.结果表明,纳朵洞洞穴水的水化学类型主要为HCO_3~--Ca~(2+)型,除每年降水量最大的月份外,滴水和池水长期处于沉积状态;纳朵洞3个滴水点的离子浓度由于岩溶水在洞顶的运移路径和时间不同存在一定差异,池水因受到洞穴混合水和洞穴空气较高CO2浓度的影响,其离子浓度高于滴水且变化幅度偏大;纳朵洞洞穴水地球化学指标具有显著的季节变化规律,可以很好地响应外部气候环境变化;离子浓度对极端气候事件引起的年际间降水变化的响应比较敏感:2013年雨季的Ca~(~(2+))、Mg~(2+)、SO_4~(2-)浓度高且平稳,而2014年雨季其浓度偏低且波动大,不同观测点的响应程度和时间并不一致.     

Why geodiversity matters in valuing nature's stage

Geodiversity—the variability of Earth's surface materials, forms, and physical processes—is an integral part of nature and crucial for sustaining ecosystems and their services. It provides the substrates, landform mosaics, and dynamic physical processes for habitat development and maintenance. By determining the heterogeneity of the physical environment in conjunction with climate interactions, geodiversity has a crucial influence on biodiversity across a wide range of scales. From a literature review, we identified the diverse values of geodiversity; examined examples of the dependencies of biodiversity on geodiversity at a site‐specific scale (for geosites <1 km² in area); and evaluated various human‐induced threats to geosites and geodiversity. We found that geosites are important to biodiversity because they often support rare or unique biota adapted to distinctive environmental conditions or create a diversity of microenvironments that enhance species richness. Conservation of geodiversity in the face of a range of threats is critical both for effective management of nature's stage and for its own particular values. This requires approaches to nature conservation that integrate climate, biodiversity, and geodiversity at all spatial scales.     

洞穴沉积物的环境记录研究进展

云贵高原有着独特的地理环境 ,其气候变迁应与青藏高原这一特殊的高海拔、低纬度的隆升地块有重要关系。洞穴化学沉积物是响应环境变化的地质记录档案 ,通过对它蕴藏的古气候信息的解译 ,可以反演过去的气候变化。本文侧重介绍了洞穴次生化学沉积物研究近年来取得的最新成果及其研究现状 ,并利用其在古环境研究中的优点 ,来讨论青藏高原的抬升对西南地区环境变化产生的屏蔽效应的可能性。     

贵州省洪家渡电站K40溶洞封堵处理方法分析

本文对贵州省洪家渡电站K40溶洞封堵处理设计与施工进行了分析,并提出了岩溶地区复杂地质条件的处理方法。即在查清地质条件的基础上,采用分区处理,多种工程手段相结合的措施。     

泛化理解下的生态旅游发展思考——以南京珍珠泉旅游度假区为例

20世纪80年代初,许多学者提出了生态旅游的概念,以期解决旅游业中人与自然日趋激烈的矛盾,如今生态旅游已渐渐成为旅游业的发展方向。文章在概念的泛化理解下分析了发展生态旅游的核心,并以南京珍珠泉旅游度假区为例,阐述了其多方面的开发优势,提出其开发原则、理念和发展生态旅游的框架,以期对长江流域乃至全国的旅游资源开发提供借鉴。