Ecological problems of development of the Ozyornoye lead and zinc deposit (Western Transbaikalia)

We outline the natural conditions of the area of the Ozyornoye deposit, the population and economy of the territory, the geological structure of the deposit, and the technological patterns of its development. We examine the sources of environmental impact, and the technical means of resolving this problem. Some ways to optimize the ecological situation in the area of development of the deposit are discussed.     

Risks of construction and operation of heat and power generating facilities (as exemplified by Sakhalin oblast)

The ecological risks of construction and operation of heat and power generating facilities in Sakhalin oblast have been investigated on the basis of a comparative-geographical analysis of the study areas. Risks are considered, which are associated with selection of main fuel for Sakhalin GRES–2 Power Plant, a change in the land use pattern and, hence, a loss of the ecological functions of geosystems, and with unfavorable natural conditions which are exacerbated in the construction process of the power plant. Vulnerable geosystems are revealed, and the eventual negative changes in the structure of flora and fauna in the construction area are determined. The problems of chemical and physical pollution caused by the operation of the projected GRES–2 are considered. The legal and socio-cultural aspects of the risks caused by construction activity are taken into consideration. Alternative variants are proposed for the siting of GRES–2 from the perspective of ecological risks: in the area of the village of Ilyinskoe (Tomarinskii district), on the western shore of Sakhalin; nearby the coal deposit in the Uglegorskii municipal district, and on the shore of the Terpeniya Gulf in the Poronaiskii district, in the immediate vicinities to the existing Sakhalin GRES–1. It was found that the industrial site of the existing Sakhalin GRES–1 in the area of the village of Ilyinskoe (Tomarinskii district) is an optimal variant for the construction from the standpoint of ecological risks.     

The problems of development of the Kholodninskoye lead and zinc deposit (Northern Baikal region)

We examine the pre-project data related to development of the Kholodninskoye lead and zinc ore deposit from the standpoint of ecological and economic soundness of the proposed production and engineering aspects of the design. Some of the proposals and recommendations are aimed at improving environmental safety of the projected facilities for extraction and benefication of mineral raw materials in conditions of the Central Ecological Zone of the Baikal Natural Territory, a World Natural Heritage Site.     

水生植物的生态功能和资源应用

水生植物具有水体产氧、氮循环、吸附沉积物、抑制浮游藻类繁殖、减轻水体富营养化、提高水体自净能力的重要功能,同时还能为水生动物、微生物提供栖息地和食物源,维持水岸带物种多样性.通过综述国内外水生植物的研究进展,阐明了水生植物的概念及分类方法,全面概述了水生植物的生态功能,讨论了中国城市建设中水生植物资源利用现状和效果,提...     

中国的脆弱生态带与土地荒漠化

土地荒漠化是当前世界上一个重要的生态环境问题, 也是一个脆弱生态失去平衡迫切需要治理的国土整治问题。作者根据联合国环境署关于土地荒漠化的评估, 结合我国情况认为, 土地荒漠化是在脆弱生态条件下, 由于人为强度活动、经济开发、资源利用与环境不相协调下出现了类似荒漠景观的土地生产力下降的环境退化过程。一类是沙质地表叠加干旱多风和强度土地利用形成的沙质荒漠化(沙漠化), 另一类是流水作用叠加土状堆积物(或风化壳)和人为强度土地利用形成的土地荒漠化。土地荒漠化是脆弱生态带内环境退化表现的主要形式, 而荒漠化的发展又加深了脆弱生态带内生态平衡的严重失调, 环境更趋于严重恶化, 构成了对人类经济发展与生存环境改善的严重威胁。但是, 只要建立防止土地退化又促进生产发展的资源节约型、适度开发型、环境保护型的经济体系, 采取因地制宜的治理措施, 从而达到生态、经济、社会三个效益, 是克服我国脆弱生态地带环境退化、资源危机的基本对策。建议在我国不同脆弱生态带建立示范区, 开展改善环境、治理土地荒漠化的研究。     

汾河源区不同景观带表土粒度与地球化学元素组成分析

基于ArcGIS,将汾河源区景观带谱分为亚高山草甸带、针阔叶林带、灌丛荒草带和河流两岸农田耕作带等4个类型,并对不同景观带表土沉积粒度和地球化学元素进行了初步分析。结果表明汾河源区表土沉积物以粉砂为主,辅以一定数量的极细砂和粘土,细砂和中粗砂含量较低;总体上沉积物分选差,呈正偏和极正偏的分布,峰态中等到尖窄;沉积物沉积环境复杂多样,风成、海相/河流沉积并存,与区域地质构造运动、风成物质堆积和河流发育有着密切的关系。地球化学元素分析发现该区表土沉积以SiO₂、Al₂O₃、Fe₂O₃为主,与上部陆壳（UCC）和中国黄土（CL）相比具有显著的同源性;而Ca和Mg等活动性元素则随海拔高度影响的降水变化呈现明显的垂向差异;沉积物化学风化基本处于脱Ca和Na的初级阶段,属寒冷干燥条件下的低等化学风化。研究旨在揭示沉积物粒度特征和地球化学行为,为进一步认识汾河源区生态环境变化提供理论基础和数据支撑。     

湘江沉积物重金属元素环境地球化学特征

在前人研究的基础上,对湘江干流河道表层沉积物及入湖三角洲地区沉积物中的重金属富集特征、赋存状态等进行了总结;对湘江沉积物中重金属的污染来源进行了分析,湘江沉积物重金属的富集种类主要受流域富集矿产的控制,重金属污染主要是人为活动导致的点源污染集中和高排放引起的;另外,运用Hakanson潜在生态风险指数和地累积指数对湘江沉积物中重金属的潜在生态风险和污染程度进行了评价,结果显示Cd、Pb、As、Zn、Cu、Hg等重金属在湘江沉积物中存在不同程度的污染,其中Cd、Hg、As、Pb、Cu污染严重同时潜在生态危害也大,应引起重视。     

兰坪—思茅盆地钾盐矿床的物质来源探讨

云南兰坪—思茅盆地是我国重要的成钾盆地。综合前人的研究成果,简要介绍了该地区的地质概况。对兰坪—思茅盆地钾盐矿床的物质来源进行了阐述和讨论,认为该盆地钾盐矿床的物质来源以残存古海水为主,并有陆源水体的补给。盆地内的富钾火山凝灰岩、古盐和风化盐也可能为该盆地钾盐矿床提供物源,至于深部地下卤水是否提供物源还需更深入的研究论证。兰坪—思茅盆地钾盐矿床成矿物源具有多源性。     

"富营养化湖泊治理及湖泊管理昆明国际讨论会"综述

湖泊富营养化是国际上普遍存在而倍受关注的问题。以国家列为“三河三湖”重点环保项目整治的滇池为首的云南九大高原湖泊中,有6个已富营养化。在云南省即将大规模开展湖泊治理工作之际,为借鉴国际湖泊治理及管理的方法及成功的经验,2001年11月召开了此次会议。有众多国际湖泊学权威在内的10个国家的163名专家出席会议。重点讨论了5个主题：湖泊治理及管理研究;湖泊环境变化的沉积记录;湖水氮、磷负荷与湖泊生态健康;湖泊污染与治理;湖泊富营养化过程。专家们对云南高原湖泊的治理提出了4个方面的建议：以改善、恢复湖泊生态系统结构的方法控制富营养化;清淤一定要慎重;加强湖泊富营养化过程与机制的研究;加强流域管理研究。会议最后发表了《昆明宣言》,建议建立云南高原湖泊国际研究中心。     

Complex internal architecture of a debris‐flow deposit revealed using ground‐penetrating radar,Cass, New Zealand

Previous research on debris‐flow deposit structure typically reports little to no visually discernible stratigraphy. The preliminary findings presented here provide evidence for more complex internal deposit architecture with inverse grading and subunits thought to reflect individual flow surges. Ground‐penetrating radar surveys, geospatial data and field observations are used to describe 10 subunits traceable over the 14 lateral radargrams imaging the lower 38 m of the deposit. Additional subunits are depicted further upslope in a longitudinal transect. As well as demonstrating the need for continued investigation of deposit architecture using non‐traditional techniques, these results may help improve future interpretations of post‐event deposits.     

地球化学研究方法在钾盐找矿中的应用

钾盐是我国的紧缺矿产资源之一,寻找钾盐资源尤其是古钾盐矿床对于我国具有重要的意义。但是由于钾盐易溶,在地表很少有成矿标志,所以加大了找矿的难度。通过论述地球化学方法在蒸发岩研究中的应用情况,指出地球化学方法在寻找钾盐的过程中有着重要的应用,其应用可以概括为:可以判断成盐古卤水的蒸发浓缩阶段和矿床的成矿阶段、揭示盐类矿床的物质来源及其沉积环境、划分蒸发岩的沉积旋回和重现古盐湖的演化过程以及分析成盐盆地的封闭蒸发条件和氧化还原性等。云南兰坪—思茅盆地是我国最具有找钾希望的区域,研究盆地内蒸发岩的地球化学特征对于在盆地内寻找钾盐矿床具有重要的指示意义。     

西安翠华山古崩塌性滑坡体的沉积特征及其形成过程

西安翠华山风景地貌由古崩生滑坡体高速运行堆积而成,堆积体存在一些反映其运动和动力状况的沉积特征,将崩塌性滑坡体的平面堆积体划分出５个平面相带;中央相带、边缘相带、抛掷相带、气浪溅泥相带和特殊的残留相带,各带有不同的沉积特征,反映出调整运动中的崩塌式滑坡体动力过程和沉积过程在平面上分布的差异,通过研究该古积物的粒径变化、砾石组构和沉积结构、构造的差异,认为该崩塌式滑坡体在运动和沉积过程,存在前后部位     

Estimation of undiscovered deposits in quantitative mineral resource assessments—examples from Venezuela and Puerto Rico

Quantitative mineral resource assessments used by the United States Geological Survey are based on deposit models. These assessments consist of three parts: (1) selecting appropriate deposit models and delineating on maps areas permissive for each type of deposit; (2) constructing a grade-tonnage model for each deposit model; and (3) estimating the number of undiscovered deposits of each type. In this article, I focus on the estimation of undiscovered deposits using two methods: the deposit density method and the target counting method.In the deposit density method, estimates are made by analogy with well-explored areas that are geologically similar to the study area and that contain a known density of deposits per unit area. The deposit density method is useful for regions where there is little or no data. This method was used to estimate undiscovered low-sulfide gold-quartz vein deposits in Venezuela.Estimates can also be made by counting targets such as mineral occurrences, geophysical or geochemical anomalies, or exploration plays and by assigning to each target a probability that it represents an undiscovered deposit that is a member of the grade-tonnage distribution. This method is useful in areas where detailed geological, geophysical, geochemical, and mineral occurrence data exist. Using this method, porphyry copper-gold deposits were estimated in Puerto Rico.     

山东省广饶县土壤重金属来源、分布及生态风险

选取山东省广饶县作为研究区,采集300个表层土壤样品（0~20 cm）,测定As、Cd、Co、Cr、Cu、Hg、Mn、Ni、Pb和Zn等10种重金属含量;运用多元统计和地统计分析方法揭示广饶县土壤重金属元素的来源与空间分布特征,最后利用H?kanson潜在生态风险指数法评价重金属的潜在生态风险。结果表明：① 研究区土壤中Co和Pb的平均值低于山东省背景值,其他8种元素的平均值均超过山东省背景值;特别是Cd和Hg的平均含量分别达到山东省背景值的1.86倍和2.50倍,说明在土壤中存在明显的富集。② As、Co、Cr、Cu、Mn、Ni和Zn为自然源,受成土母质控制;Hg为人为源,主要来源于煤炭燃烧和工业排放;Cd和Pb受自然和人为因素共同控制。③ 成土母质控制着As、Cd、 Co、Cr、Cu、Mn、Ni、Pb和Zn的基本分布格局,不同土地利用类型的土壤Hg含量差别较明显,其高值区集中在城镇建设用地。④ 总体上,研究区为中等生态风险的偏高水平,其中Cd和Hg分别为中等和较高生态风险,其余8种元素处于低生态风险。     

Map Scale Effects on Estimating the Number of Undiscovered Mineral Deposits

Estimates of numbers of undiscovered mineral deposits, fundamental to assessing mineral resources, are affected by map scale. Where consistently defined deposits of a particular type are estimated, spatial and frequency distributions of deposits are linked in that some frequency distributions can be generated by processes randomly in space whereas others are generated by processes suggesting clustering in space. Possible spatial distributions of mineral deposits and their related frequency distributions are affected by map scale and associated inclusions of non-permissive or covered geological settings. More generalized map scales are more likely to cause inclusion of geologic settings that are not really permissive for the deposit type, or that include unreported cover over permissive areas, resulting in the appearance of deposit clustering. Thus, overly generalized map scales can cause deposits to appear clustered. We propose a model that captures the effects of map scale and the related inclusion of non-permissive geologic settings on numbers of deposits estimates, the zero-inflated Poisson distribution. Effects of map scale as represented by the zero-inflated Poisson distribution suggest that the appearance of deposit clustering should diminish as mapping becomes more detailed because the number of inflated zeros would decrease with more detailed maps. Based on observed worldwide relationships between map scale and areas permissive for deposit types, mapping at a scale with twice the detail should cut permissive area size of a porphyry copper tract to 29% and a volcanic-hosted massive sulfide tract to 50% of their original sizes. Thus some direct benefits of mapping an area at a more detailed scale are indicated by significant reductions in areas permissive for deposit types, increased deposit density and, as a consequence, reduced uncertainty in the estimate of number of undiscovered deposits. Exploration enterprises benefit from reduced areas requiring detailed and expensive exploration, and land-use planners benefit from reduced areas of concern.     

新疆松湖铁矿地质特征与成矿期次划分

新疆松湖铁矿床位于伊犁地块东北部,矿体赋存于下石炭统大哈拉军山组火山碎屑岩中．目前共圈定5个矿体,L1、L2出露,IJ3、L4、L5矿体隐伏,其中L1规模最大,也是该矿床主要矿体．矿床主要矿石矿物为磁铁矿,次为赤铁矿、黄铁矿和褐铁矿．矿石构造类型主要为浸染状、块状、角砾状和条带状构造．蚀变类型主要有绿帘石化、绿泥石化、阳起石化和钾长石化．矿床形成经历了隐爆一矿浆成矿期和热液成矿期2个阶段．该矿床成因类型属于受热液作用交代改造的火山岩型铁矿．     

On a proposed plutonic porphyry gold deposit model

A plutonic porphyry gold deposit model is proposed that is imilar to the plutonic porphyry copper deposit model. However, unlike the plutonic porphyry copper deposit model, the proposed model is deficient in copper and contains less than 1 percent total sulfides. In the proposed model, gold is accompanied by scheelite, molybdenite, arsenopyrite, a variety of bismuth sulfides, tellurides, and native bismuth. The host rock varies from granite to granodiorite stock. Most of the ore is in the pluton. Deposits cited as examples of the proposed model are the Mokrsko deposit in Czechoslovakia, the Fort Knox deposit in the United States, and the Dublin Gulch deposit in Canada. In each of these deposits, pervasive potassic or phyllic alteration zones accompany the gold ore, which is disseminated in quartz-rich stockworks, veinlet swarms, and veins. Tonnages of gold-bearing material are large, but grades are low in the cited deposits. The proposed model is distinct from other gold deposit models because of the low Cu to Au ratio and the association of Au, Bi, W, and Mo.     

Use of Noise to Augment Training Data: A Neural Network Method of Mineral–Potential Mapping in Regions of Limited Known Deposit Examples

One of the main factors that affects the performance of MLP neural networks trained using the backpropagation algorithm in mineral-potential mapping isthe paucity of deposit relative to barren training patterns. To overcome this problem, random noise is added to the original training patterns in order to create additional synthetic deposit training data. Experiments on the effect of the number of deposits available for training in the Kalgoorlie Terrane orogenic gold province show that both the classification performance of a trained network and the quality of the resultant prospectivity map increasesignificantly with increased numbers of deposit patterns. Experiments are conducted to determine the optimum amount of noise using both uniform and normally distributed random noise. Through the addition of noise to the original deposit training data, the number of deposit training patterns is increased from approximately 50 to 1000. The percentage of correct classifications significantly improves for the independent test set as well as for deposit patterns in the test set. For example, using ±40% uniform random noise, the test-set classification performance increases from 67.9% and 68.0% to 72.8% and 77.1% (for test-set overall and test-set deposit patterns, respectively). Indices for the quality of the resultant prospectivity map, (i.e. D/A, D × (D/A), where D is the percentage of deposits and A is the percentage of the total area for the highest prospectivity map-class, and area under an ROC curve) also increase from 8.2, 105, 0.79 to 17.9, 226, 0.87, respectively. Increasing the size of the training-stop data set results in a further increase in classification performance to 73.5%, 77.4%, 14.7, 296, 0.87 for test-set overall and test-set deposit patterns, D/A, D × (D/A), and area under the ROC curve, respectively.     

聚焦变化中的盐湖:二次科考盐湖专题阶段性研究进展

青藏高原是我国重要的生态屏障,也是重要的盐湖分布区。在青藏高原第一次综合科考时曾对青藏高原盐湖开展过系统调查。二次科考在一次科考的基础上,加强了对一些工作程度不够的极端困难区的补充调查,还重点开展了气候变化及资源开发双重影响下青藏高原盐湖资源与环境的变化趋势;现代盐湖关键元素迁移、富集规律;古钾盐成矿预测;盐湖资源开发的生态环境效应等研究工作。经过近3年的系统工作,专题获得了大量一手科考数据,已取得了一批有显示度的科学成果。研究系统介绍了盐湖专题科考方案的整体思路、研究内容、技术路线、前期获得的亮点成果及下一步工作计划等。     

生态安全：国内外研究综述

生态安全是21世纪人类社会可持续发展所面临的一个新主题。本文归纳了学术界对生态安全概念的各种理解和认识，并将生态安全内涵概括为：（1）生态系统自身的健康、完整和可持续性，（2）生态系统对人类提供完善的生态服务。简述了生态安全的研究内容，提出了生态安全研究框架。综述10年来生态安全方面的研究进展，概括出生态安全研究十几年来的3个基本理论：①生态系统健康与环境风险评价理论;②环境（生态）安全的国家利益理论;③生态权利理论及其法律实践，以及生态安全研究所采用的几种主要技术方法，最后提出了生态安全研究展望。