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331.
环境矿物材料应用在重金属污染治理中越来越受到人们的关注,而通过有机改性可以有效提高其治理效果。结合国内外对环境矿物材料的有机改性研究,综述了应用于重金属污染治理的环境矿物材料有机改性的研究进展,并提出了发展趋势和展望。  相似文献   
332.
铅低积累大豆的筛选及铅对其豆中矿物营养元素的影响   总被引:3,自引:0,他引:3  
筛选和培育铅低积累作物品种已被用来降低铅流入到人们的食物链中.本实验采用盆栽方法,研究了16个选定的大豆品种在两个铅处理(500和1500 mg·kg-1)下的生长反应,并评估其对铅的耐性.结果表明,在两个铅处理(500和1500 mg·kg-1)下,大豆中Pb含量有显著差异(p0.05),其平均值分别为0.19和0.27 mg·kg-1.在两种Pb梯度处理下富集系数的范围分别为0.003~0.014和0.002~0.012.16种大豆品种的富集系数在两种Pb梯度处理下均小于0.02,且存在显著差异(p0.05),表明大豆吸收的Pb主要积累在根部.大豆品种:垦丰16号、绥农28号、中黄35号和黑河35号被发现符合低铅积累大豆品种的标准.这4个品种的大豆被进一步用于评估Pb和其他矿质营养元素之间的相互作用,如Ca、Cu、Fe、Mg、Mn和Zn.土壤中Pb含量会影响大豆对微量矿物营养元素的吸收,表现为土壤中高剂量Pb能抑制大豆对Ca、Cu、Fe、Mg和Zn的吸收,同时增加其对Mn的吸收和积累.  相似文献   
333.
采用水培法研究模拟酸雨(p H=5.0、3.5、2.5)对水稻叶片质膜H+-ATPase活性与矿质元素含量的影响.结果显示:与对照(CK)相比,酸雨处理5 d(胁迫期)后,p H=5.0组质膜H+-ATPase活性与活化能、K+、Ca2+、Mg2+含量均无显著变化,仅细胞渗透势下降.p H=3.5酸雨导致细胞渗透势、K+含量下降,质膜H+-ATPase活性、H+-ATPase活化能、Ca2+含量明显上升,Mg2+含量无显著变化.p H=2.5组H+-ATPase活性、细胞渗透势和K+、Mg2+含量明显下降,H+-ATPase活化能和Ca2+含量上升,表明矿质元素含量不仅受H+-ATPase活性的调控,还与酸雨强度和离子价态有关.经5 d恢复(恢复期)后,p H=5.0组各指标均恢复到CK水平,p H=3.5组除细胞渗透势外均恢复至CK水平,p H=2.5处理组各指标虽未达到CK水平,但较胁迫期有所恢复.表明K+、Ca2+、Mg2+含量受H+-ATPase活性的调节,且恢复效果受酸雨强度影响.  相似文献   
334.
Impacts from climate change pose a raft of challenges for societies, governments and policy-makers internationally. The anticipated changes are well documented, including rising sea levels, increased floods and other extreme weather conditions. Much research and policy emphasis has focused on technical and economic aspects. Less debated are questions about different communities' vulnerabilities, inequitable distributional impacts, social justice issues and how vulnerability links to social inclusion/exclusion. This paper explores a case study mapping social exclusion and vulnerability in Brisbane, Queensland, which found that while communities can be vulnerable through physical aspects of an area when social dimensions are added to the equation it amplifies or exacerbates the scale of vulnerability. The findings also suggest that in developing research agendas and policy debates around climate change, there could be benefits from interlinking the currently separate areas of work on social vulnerability to extreme weather events, to forms and processes of social inclusion/exclusion.  相似文献   
335.
Informal recycling networks are systems through which impoverished populations earn money and residents recycle waste which might otherwise go into a landfill. These networks, in which people voluntarily self-organise to collect recyclables, occur throughout the world. This article discusses results of an exploratory, qualitative study of one such network in St. John's, Newfoundland and Labrador which identifies motivational characteristics of the network and their implications for public policy. Through close attention to particularities of place, the research identified community interaction and community inclusion as two of the most active motivating factors within the studied network. The findings suggest public recycling programmes can increase public participation through greater attention to place-based motivational factors. Such participation could contribute to increased sustainability and reach of recycling programmes.  相似文献   
336.
In general, CO2 sequestration by carbonation is estimated by laboratory experimentation and geochemical simulation. In this study, however, estimation is based on a natural analogue study of the Miocene basalt in the Kuanhsi-Chutung area, Northwestern Taiwan. This region has great potential in terms of geological and geochemical environments for CO2 sequestration. Outcropping Miocene basalt in the study area shows extensive serpentinization and carbonation. The carbon stable isotopes of carbonates lie on the depleted side of the Lohmann meteoric calcite line, which demonstrates that the carbonates most probably precipitate directly from meteoric fluid, and water–rock interaction is less involved in the carbonation process. Oxygen stable isotope examinations also show much depleted ratios, representative of product formation under low temperatures (∼50–90 °C). This translates to a depth of 1–2 km, which is a practical depth for a CO2 sequestration reservoir. According to petrographic observation and electron microprobe analysis, the diopside grains in the basalt are resistant to serpentinization and carbonation; therefore, the fluid causing alteration is likely enriched with calcium and there must be additional sources of calcium for carbon mineralization. These derived geochemical properties of the fluid support the late Miocene sandstone and enclosed basalts as having high potential for being a CO2 sequestration reservoir. Moreover, the existing geochemical environments allow for mineralogical assemblages of ultramafic xenoliths, indicating that forsterite, orthopyroxene and feldspar minerals are readily replaced by carbonates. Based on the mineral transformation in xenoliths, the capacity of CO2 mineral sequestration of the Miocene basalt is semi-quantitatively estimated at 94.15 kg CO2 chemically trapped per 1 m3 basalt. With this value, total CO2 sequestration capacity can be evaluated by a geophysical survey of the amount of viable Miocene basalt at the potential sites. Such a survey is required in the near future.  相似文献   
337.
Small-scale mining is more prevalent in India. The maximum production capacity of 50,000 tonnes/year has been accepted as a criterion to Indian small-scale mine. Such mines constitute about 90% of total number of mines, 42% of the total non-fuel minerals and metals, 5% of the fuel minerals. Some 3000 small scale mines account for a work force of about 0.5 million people. Yet this sector is a neglected sector in Indian economy and still considered as an unorganized sector. This paper examines the contribution of small-scale mines to employment and national mineral production, practices, and Indian policy on small-scale mining. It identifies the drawbacks in the existing Government policy and discusses the role of Government for up gradation in this sector. It focuses the need for technical up gradation and to ensure the economic and social infrastructure. It also discusses how the pursuit of sustainable livelihoods, poverty alleviation and indigenous peoples right in artisanal and small-scale mining be more effective when these communities are disadvantaged or neglected by Government policies. This paper concludes that this sector can make significant contribution to Indian economy and employment generation. It recommends that by establishing mining centre consist of shared mining and processing facilities, educating and training related initiatives it can be achieved.  相似文献   
338.
本文论述了开展矿产资源经济评价对准确掌握各类矿产资源的数量和进行勘探及资源开发决策的重要性,阐述了矿产资源经济评价的基本原理,提出了经济评价基本模型及从经济角度对资源进行分类的标准和确定资源优先开发顺序的比较方法。  相似文献   
339.
杨勇 《四川环境》1992,11(3):1-4
本文对长江上游雅砻江一带的藏、汉、彝和纳西等民族混合居住地区的文化、社会、生产、生活习俗,地形、地质、地貌演变,以及森林砍伐,乱开矿山,随意捕杀动物等人为活动,造成了水土流失、滑坡、泥石流和地震等自然灾害。破坏了自然生态环境,给当地开发丰富的水资源和矿产资源带来了极大的影响。  相似文献   
340.
为探究矿物碳酸化与污泥厌氧消化耦合过程中实现CO2捕获和N/P营养盐协同回收的可行性,在污泥水解液为底物的厌氧消化系统中,研究不同比例Mg2+/Ca2+离子添加对厌氧消化系统中CO2捕获和营养盐的协同回收效果的影响.结果表明,添加Mg2+/Ca2+离子为(20mmol/L)/(0mmol/L)、(10mmol/L)/(10mmol/L)和(0mmol/L)/(20mmol/L)均可促进有机质降解,使沼气产量分别提升16.97%、21.56%和23.99%,并使CO2含量由27.27%分别下降至24.81%,22.06%和21.98%.不同比例Mg2+/Ca2+离子添加可使磷酸根浓度下降63.46%~66.47%,但仅Mg2+/Ca2+离子以(20mmol/L)/(0mmol/L)和(10mmol/L)/(10mmol/L)添加的实验组中氨氮浓度得到下降.XRD分析揭示,Mg2+/Ca2+离子以(20mmol/L)/(0mmol/L)、(10mmol/L)/(10mmol/L)和(0mmol/L)/(20mmol/L)添加时分别使厌氧消化系统中形成鸟粪石和碳酸镁、鸟粪石和方解石、方解石和三斜磷钙石.Mg2+、Ca2+离子等摩尔量联合添加可实现最优的CO2捕获和营养盐协同回收效果.  相似文献   
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