首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 140 毫秒
1.
Recently, the impacts of increasing atmospheric CO2 level on the terrestrial ecological system have been intensively studied. The higher the CO2 concentration, the higher the risk of destabilizing vulnerable carbon pool on ecological safety. Metabolism, biomass, activity, and diversity of microbial communities in soils can be significantly altered by the CO2 enrichment. For instance, it may accelerate carbonate weathering, vary the rhizospheric exudation, and enhance the amount of available C from the upper soil layer. However, how the CO2 enrichment would influence food safety such as species transformation and bioavailability of heavy metals in soils is remained unanswered. The bioavailability of heavy metals is strongly affected by bio-factors in addition to the physiochemical conditions of soils. Different physiological mechanisms and states control plant uptake of heavy metals. The enrichment of CO2 influences physiological functionalities of plants, and in turn, is expected to have impacts on the bioaccumulation of pollutants and the stress adjustment system of plants. Currently, in China soil is heavily polluted, in most cases, combined by organic pollutants and heavy metals. Studies of the environmental behavior and ecological effect of Cu in soil under elevated CO2 levels were conducted in China FACE (Free Air Carbon Dioxide Enrichment) from June to October 2005 using pot experiments. Results showed that the accumulation of Cu and Cd in leaves, stems, roots, and grains of rice growing in Cu contaminated soils was significantly lowered, indicating that the bioavailability of heavy metals in soils decreases with increasing CO2 concentration.  相似文献   

2.
Recently, the impacts of increasing atmospheric CO2 level on the terrestrial ecological system have been intensively studied. The higher the CO2 concentration, the higher the risk of destabilizing vulnerable carbon pool on ecological safety. Metabolism, b…  相似文献   

3.
The mining environment, medical geology and urban geochemistry form a group of related scientific disciplines that have developed strongly during recent years in the Nordic countries. Modern legislation controls the environmental issues. Close co-operation of researchers and legislators has improved the quality and safety of life in the societies of the Nordic countries. In mining environmental studies, methods that are suitable in Arctic conditions have been developed; in medical geology, the input from the Nordic countries has made it an appreciated scientific discipline throughout the world, and in the case of the urban environment, methods developed by our geochemists have especially improved the health conditions, particularly of children.  相似文献   

4.
The study aimed to assess the heavy metals(K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, As, Pb, Sr, Zr) contamination in the soil of mine affected Singaran river basin and to analyse spatial variation in the contamination level considering 32 soil samples. Elemental analysis of soil samples has been performed through Energy Dispersive X-ray Analysis(EDX) to quantify the elemental concentration(mg kgà1). Heavy metal concentrations have been assessed through geo-accumulation index(Igeo) and enrichment factor(EF).Indices showed soils have moderate accumulation of most of the metals with moderate enrichment of Sr,Zr, Zn, Cu and Ni. Soil contamination level assessment has been carried out using indices like Contamination Factor(CF), degree of contamination(C_(deg)), modified degree of contamination(m C_(deg)) and Pollution Load Index(PLI). CF shows moderate to considerable contamination by Sr, Zr, Ca, Cu, Mn, Zn and Ni. Mean indices values(m C_(deg)and PLI for the entire basin are 3.38 and 2.23 respectively) show low to moderate level of soil contamination. These indices result have been mapped and analysed in GIS platform to get spatial variation of pollution level. Opencast mines dominate middle catchment area and so is comparatively contaminated. Sample sites 11, 18 and 25 evidenced high values of all indices of pollution load. From the ecological standpoint Ecological Risk Factor(Er) and Potential Ecological Risk Index(RI) have been estimated to assess regional threat to native soil environment and it shows low ecological risk potential. Analysis shows that mine dominated soil of the entire Singaran basin is less contaminated in all respect but tends to the moderate contamination level at the mid-catchment area,especially by Sr, Zr, Zn, Cu and Ni.  相似文献   

5.
燕金寿 《地球化学》1975,(4):291-296
Some soft and mud samples have been determined for eadmiun, lead, copper,nickel and cobalt by atomic absorption speetrophotometry with a high-temperature graphite tube, after their extraction with sodium diethylthiocarbonate into methy lisolutyl ketone. The tests of the effects of acidity on extraction and interference have been also carried out and the optimum conditions have been obtained. In addition, experiments on recoveries by this procedure have been performed for the elements in ppb amount. The recovery of the metals added to soil samples is made in the same manner and the precision values are given in this paper. This method is considered as to be applicable to the determination of soil and mud samples for the above-mentioned elements, of which the concentration is higher than 1 ppb.  相似文献   

6.
Glass and gas inclusions have been observed in olivine and other minerals in 30 doubly polished tin sections of Jilin meteorites, indicating that there must have been melting And condensation stages during the process of meteorite formation. Temperatures of formation have been determined by homogenization and quenching runs,giving 1050-200℃ and 502℃ for glass and gas inclusions respectively, Meanwhile,the fibrous radial crystals of pyroxene have been notieed to grow when heated over 800℃. These observations are in general agreement with the available experimental data and theoretical calculations regarding meteorite.  相似文献   

7.
At gold mining in the 19th~20th centuries on technogenous deposits of cryolitozone, considerable amounts of mercury-containing elements (amalgams) have been accumulated. Urgency of their utilization is caused by necessity of providing safe vital activity. It can be achieved when elaborating up-todate technologies providing self-support of utilization as a consequence of extracting precious metals. Difficulty of this problem realization is caused by the absence of theoretical and applied elaborations of making the appropriate works in cryolitozone. The main trends of the problem solving on the grounds of creating scientific method foundations for investigating the cryolitozone amalgams transformation have been considered in the paper. Dynamics has been shown and the revealed regularities of their transformation,testifying of the occurrence of hydrometallurgic processes in cryolitozone massifs in situ, resulted in the decline of gold reserves at decreasing dispersity and increasing hallmarking, have been analyzed.  相似文献   

8.
翁文灏  王紹文 《地质学报》1930,9(2):106-120
The crystallographical study of the newly found crystals of topaz was started by W. H. Wong and continued and completed by S. W. Wang under the supervision of the former. The angular measurements have been taken  相似文献   

9.
西藏南部花岗岩类中微量元素的某些地球化学特征   总被引:1,自引:0,他引:1  
Types and intrusion times of granitoid rocks in Southern Xizang have been distingui.shed by diseriminatory and cluster analyses. By means of regression analyses, we discussed quantitatively the correlations between trace and major elements and the characteristics of trace element evolution. The features of trace element distribution and evolution have been discussed as well. It has been indicated, that the granitoid recks of different periods are resulted from partial melting to various extents in the lower crust or in the upper crust.  相似文献   

10.
《地球化学》1973,(4):272-275
The concentrations of radiogenic Ar^40 and cosmogenic Ar^32 in Anlung chondrite have been measured by the isotopic dilution technique. A ultrahigh-vacuum system have been designed for extracting and purifying the gases in the sample. These data provide a K^40-Ar^40 age of 3.28 b.y. and an exposure age of 3.0 m,y. for this chondrite.Based on these results, we have discussed the origin and the former environment of stone meteorite.  相似文献   

11.
基于DPSIRM框架模型的高原湿地生态安全评价   总被引:2,自引:0,他引:2  
秦趣  梁振民  刘安乐  赵增友 《冰川冻土》2020,42(4):1363-1375
综合考虑高原湿地生态安全的资源、 环境、 生态、 社会、 经济等影响因素, 以驱动力-压力-状态-影响-响应-管理(DPSIRM)框架模型建立高原湿地生态安全DPSIRM评价指标体系, 采用灰色关联法对各评价指标赋权重值, 运用集对分析法建立评价模型, 对威宁草海2011 - 2016年的湿地生态安全进行评价研究。结果显示: 人口自然增长率、 单位工业产值废水排放量、 生活污水排放量、 化肥施用强度、 农药施用强度、 人均水资源量、 物种多样性、 水土流失率、 物质生产、 湿地面积退化率、 污水处理率、 物质生活指数、 环保投资指数和政策法规实施力度等是影响威宁草海湿地生态安全的主要因素; 威宁草海湿地生态安全逐渐转好, 2011 - 2012年草海湿地生态安全属于不安全等级, 2013 - 2016年属于临界安全等级; 从各子系统情况看, 驱动力子系统为较安全等级, 压力、 状态、 影响、 响应和管理子系统均为临界安全等级, 响应子系统为不安全等级, 成为影响威宁草海湿地生态安全的重要系统。研究成果可为威宁草海湿地的生态安全和环境建设提供科学参考。  相似文献   

12.
湖泊蓝藻水华生态灾害形成机理及防治的基础研究   总被引:9,自引:0,他引:9  
湖泊具有供水、渔业、旅游、维持区域生态系统平衡等功能,是支撑我国经济和社会发展的重要资源之一。但是近30年来,湖泊富营养化所导致的蓝藻水华频繁暴发,生态灾害事件频发,严重影响湖泊功能的发挥, 制约区域经济可持续发展。针对国家在保障区域水安全和生态安全、保护人民健康及建设和谐社会等方面的重大需求,国家重点基础研究发展计划项目“湖泊蓝藻水华生态灾害形成机理及防治的基础研究”于2008年7月正式立项。项目拟解决的关键科学问题包括:①湖泊蓝藻水华主要衍生污染物的形成机理、迁移转化规律和毒理效应;②蓝藻水华导致湖泊生态系统结构变化和功能退化的机理;③蓝藻水华生态灾害评估及调控机理。针对上述科学问题,项目以蓝藻水华污染物的产生、湖泊生态系统结构与功能的响应以及生态灾害的评估与调控为研究主线,重点开展以下几个方面的研究:①蓝藻水华衍生污染物的产生及其环境过程;②蓝藻水华衍生污染物的毒理效应与生态和健康风险;③蓝藻水华导致湖泊生态系统结构变化与功能退化的关键过程和机制;④蓝藻水华灾害治理和调控的的技术原理和途径。项目的实施和完成将为我国湖泊蓝藻水华生态灾害的预防与控制提供理论和技术原理支撑。  相似文献   

13.
针对人地矛盾、粮食生产安全等日益突出的问题,泰山区结合土地开发整理工作的多年实践,因地制宜,注重实效,在土地开发整理工作中做了一些积极探索,通过健全管理制度、科学编制规划、建立监督机制和强化队伍建设等一系列措施的实施,连续4年实现了耕地总量的动态平衡,带来了显著的社会效益、经济效益及生态效益。  相似文献   

14.
土壤地球化学测量作为一种重要的勘查技术方法,历经近百年的发展历程,自从1932年苏联地质学家费尔斯曼、谢而盖耶夫等开展地球化学找矿尝试以来,其在矿产勘查、生态、环保等领域均取得了丰硕成果和长足发展.本文基于前人研究成果基础之上,通过对土壤地球化学测量发展历程回顾,通过其在多目标领域运用,在有色金属、贵金属、油气矿产、放...  相似文献   

15.
为了实现矿业城市生态安全性评价,利用BJ2、GF1、ZY3等国产高分辨率卫星影像数据,采用遥感技术手段,基于GIS平台,构建景观安全评价体系。通过获取2017年度研究区内各土地资源类型分布现状数据,进行景观指数(破碎度、分离度、优势度、干扰度、脆弱度、生态风险度)计算,逐网格剖析后采用普通Kriging插值法(半变异函数)对研究区域的景观生态安全度进行定量分析与评价。结果表明:研究区内大部分地区景观生态安全处于中、中高和高水平,面积为538 951.58 hm2,占研究区面积的86.75%,呈现由矿产资源集中开采区向其外部、平原区向低山丘陵区安全等级逐渐升高,生态环境逐渐转好的趋势;低、中低安全区总面积为82 342.18 hm2,占研究区面积的13.25%,景观生态安全仍存在较大问题,需引起地方政府关注。  相似文献   

16.
基于能值-生态足迹模型的湖北省生态安全评价   总被引:1,自引:0,他引:1  
冯芳  金爽  黄巧华  戴桂斌  张强 《冰川冻土》2018,40(3):634-642
基于能值分析法改进的生态足迹模型,对1997-2014年湖北省生态经济系统长时间序列可持续发展趋势和生态安全状况进行了定量分析。结果表明:研究期内湖北省多年平均能值密度为1.286×1015 sej·hm-2,人均能值生态承载力从1.18 hm2下降到1.10 hm2,人均能值生态足迹由4.50 hm2增加到8.72 hm2。从1998年起湖北省人均生态足迹逐年扩大,以年均6.2%的速度快速增长,一直处于生态赤字状态,且赤字增大趋势明显;生态压力指数从3.82增长到7.95,生态安全形势严峻。湖北省生态环境系统不足以维持自身经济社会快速发展,其中城市建设发展和重工业的能耗压力大以及进出口总额剧增是造成区域生态赤字的主要原因。  相似文献   

17.
我国地处欧亚板块东缘,地貌类型多样,地质条件复杂,国家重大战略的顺利实施与生态文明建设的有效推进面临着严峻的地质安全风险,因此亟需解决各种地质作用对人居环境与工程活动带来的地质安全问题。本文以地球系统科学为指导,以圈层相互作用、内外动力耦合、人地协调互馈为理论核心,聚焦国土空间地质安全、重大工程地质安全、城市建设地质安全、生态环境地质安全及资源开发地质安全等方面,分析国家战略发展面临的重大地质安全挑战,剖析地质安全牵引出的系列前沿科学问题,勾画出地质安全主要研究方向。地质安全是保障人民高质量生活、推动社会经济绿色发展、构建宜居地球的重要前提,对于解决当前和今后发展面临的重大工程建设、重大灾害防控、生态环境保护和人地和谐安居等相关地质安全问题,推进科技进步与社会可持续发展具有重要科学意义。  相似文献   

18.
矿山生态地质环境恢复治理是生态文明建设的环境基础。该文在介绍莱芜市石棚地区的地质、水文特征的基础上,对损毁山体的地质环境现状和存在危害进行了分析,提出了矿山生态地质环境恢复治理的生态、工程措施,实现了生态、社会、经济三大效益的协调发展。  相似文献   

19.
连倪 《吉林地质》2019,38(2):99-102
本次需要治理的5处矿山遗留的地质环境问题严阻碍了社会发展,使当地人居环境恶化。综合地质灾害、生态环境、气象水文条件以及居民生产活动等因素,提出合理的治理工程方案,解决治理区内突出的矿山地质环境问题,消除或减少露采边坡存在的威胁,改善生态环境,营造一个宜居、宜人的生存环境,确保地方经济的可持续发展。通过治理消除或最大限度的减少露采边坡存在的威胁,确保人民生命财产安全和社会稳定。  相似文献   

20.
矿山开采活动中地下水与生态环境保护是需要综合利用多学科思想与理论解决的难题,仅从采矿工程学角度难以解决根本问题。文中从生态水文地质学的角度,针对陕北采煤安全必须疏排水和陕北能源基地建设亟须水资源支撑的现状,提出了通过充分地利用煤田地下水满足强劲用水需求来保护水资源的对策,并从矿区水文地质结构、地下水循环条件出发,根据矿区植被生态风险区划、采煤影响地下水区划,提出了建立保护矿山水资源的采煤秩序、不同阶段地下水保护与开发利用区划以及矿山掘进过程中保护性开采地下水的水源地布局规划原则与建设方案。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号