A novel strategy using biodegradable EDDS for the chemically enhanced phytoextraction of soils contaminated with heavy metals   总被引：1，自引：0，他引：1  

Chunling LUO Zhenguo SHEN Alan J.M. Baker Xiangdong LI 《中国地球化学学报》2006,25(B08):115-115

For the sake of cost and potential environmental risk, it is necessary to minimize the amount of chelates used in chemically-enhanced phytoextraction. In the present study, a biodegradable chelating agent, EDDS was added in a hot solution at 90℃ to the soil in which garland chrysanthemum （Chrysanthemum coronarium L.） and beans （Phaseolus vulgaris L., white bean） were growing. The application of hot chelate solutions was much more efficient than the application of normal chelate solutions （25℃） in improving the uptake of heavy metals by plants. When 1 mmol kg1 of EDDS as a hot solution was applied to soil, the concentrations ofCu, Zn and Cd and the total phytoextraction by the shoots of the two plant species exceeded or approximated those in the shoots of plants treated with 5 mmol kg^-1 of normal EDTA solution. The concentrations of metals in the shoots of beans were significantly correlated with the relative electrolyte leakage rate of root cells, indicating that the root damage resulting from the hot solution might play an important role in the process of chelate-enhanced metal uptake. The soil leaching study demonstrated that decreasing the dosage of chelate resulted in decreased concentrations of soluble metals in soils. On the 28th day following the application of chelate, the concentrations of soluble metals in the EDDS treated soil were not significantly different from the concentrations in the control soil to which chelates had not been applied.  相似文献   

Permeable Reactive Barrier for the treatment of contaminated surface water in Katedan industrial development area, Hyderabad, India     

Savitri Tripathi Vandana Parth Phani Homeshwari M. Vittal Babu N. Murthy N.N. Sorlie J.E. Govil P.K. 《中国地球化学学报》2006,25(B08):117-118

Permeable Reactive Barrier （PRB） is an emplacement of inert material （s） in the subsurface, designed to intercept a contaminated plume, provides a preferential flow path through the reactive media, and transforms the contaminant into environmentally acceptable forms to attain concentration remediation goals at the discharge of the barrier. The phenomena, which help in remediation within PRB, are adsorption/sorption, precipitation, oxidation/reduction and biodegradation. Various materials like zero-valent iron, zero-valent bi-metals, natural zeolites, organic carbon, fly ash, zeolites, limestone, activated alumina, apatites, etc. have been tried by many researchers to remove organic and inorganic contaminants. In USA, Canada, and many European countries commercial full-scale and pilot scale PRBs are successfully working. The design and installation of full scale PRBs needs laboratory treatability and dynamic flow column experiments？ The concept of PRB is being applied to treat contaminated surface water in the Katedan industrial area, Hyderabad, India. National Geophysical Research Institute （NGRI）, Hyderabad, India, conducted systematic studies in collaboration with Norwegian Geotechnical Institute （NGI）, Norway, to develop PRB technique to decontaminate the surface water pollution due to industrial effluent. A site assessment study in the Katedan Industrial Area, were carried out and water, soil and sediment from the lakes of the area were found to be polluted with high concentrations of heavy metals like As, Pb, Cr, Cd, Ni, etc. Adsorption studies at NGRI with synthetic samples and in-situ industrial effluent using different reactive media for removing contaminants like arsenic, chromium, cadmium, copper, nickel, lead and zinc have been carried out and yielded satisfactory results. The performance of zero-valent iron and limestone is encouraging in removing As,  相似文献   

THE INFLUENCE OF FERTILIZERS, NaHCO3,SOIL TYPE ON CHEMISTRY OF FLOODED SOILS AND RICE PLANT GROWTH     

Ir. Lahuddin M S Zulkifli Nasution 《湿地科学》2006,4(3):161-167

1 INTRODUCTIONQuality of chemical properties of flooded soils isgenerally determined by salinity and alkalinity,bothof these acts as inhibiting factors of plant growth.Thecorrelation of electrical conductivity and other analysisindex has been reported by …  相似文献   

Naturally acidic and metalliferous waters at unmined volcanogenic massive sulfide deposits in the Bonnifield mining district, Alaska Range, east-central Alaska     

Robert G. Eppinger Paul H. Briggs Cynthia Dusel-Bacon Stuart A. Giles Larry P. Gough Jane M.Hammarstrom Bernard E. Hubbard 《中国地球化学学报》2006,25(B08):232-232

The Bonnifield district hosts 26 tmmined volcanogenic massive sulfide （VMS） occurrences. Environmental geochemical samples of water and stream sediment were collected at several occurrences, concentrating on the two best-exposed and largest deposits, Red Mountain （RM） and Sheep Creek （SC）. Limited samples were also collected at the poorly exposed WTF deposit. The deposits are Late Devonian to Early Mississippian, and are hosted by felsic metavolcanic and carbonaceous schist members of the Totatlanika Schist or Keevy Peak Fm. Spring and stream waters at RM and SC have pH values commonly 〈3.5 （as low as 2.4 at RM and 2.5 at SC）, high conductivity （up to 11000 μS/cm）, and very high （Is to 100s mg/L） dissolved contents of Al, Cd, Co, Cu, Fe, Ni, and Pb. Waters at RM are characterized by extremely high REE contents （summed REE median 3200 μg/L, n=33）. At both RM and SC, pyrite oxidation and dissolution produce low pH waters that interact with and dissolve bedrock minerals, resulting in acidic, metal-laden, naturally degraded streams that are mostly devoid of aquatic life. Ferricrete is common. In contrast, WTF barely produces a surficial environmental footprint, mostly due to topography and relief. RM and SC are well exposed in the areas of relatively high relief, and both exhibit extensive areas of quartz-sericite-pyrite-alteration. While WTF shares many of the same deposit-and alteration characteristics, it is concealed by tundra in a large, nearly flat area. Surface water at WTF is absent and outcrops are sparse. Even though WTF is roughly the same size as Red Mountain （both around 3 million tonnes） and has similar base- and precious-metal grades, the surficial geochemical manifestation of WTF is minimal. However, exposure through mining of the altered, mineralized rock at WTF potentially could initiate the same processes of pyrite oxidation, acid generation, and mineral dissolution that are observed naturally at RM and SC.  相似文献   

Quantification of the risk associated with high levels of mercury pollution at Temirtau, Kazakhstan     

Huiwen HSIAO Susanne M. Ullrich Trevor W. Tanton 《中国地球化学学报》2006,25(B08):233-233

This research aims to establish the risks of hurnan exposure to modeling approach. The study site was located on the River Nura 1990s, an acetaldehyde production plant located in the industrial high environmental mercury levels, based on a quantitative risk in central Kazakhstan. From the 1950s until its closure in the mid city of Temirtau released mercury-containing wastewater into the river. River sediments are highly contaminated with mercury up to a distance of 25 km and beyond. In addition, a local power station released an estimated 6 million tonnes of fly-ash into the water and the mercury has become quite tightly associated with the ash deposits. River water, fish and agricultural land in the floodplain are also contaminated with mercury, yet the risks posed to the local population have not been evaluated to date. In June and July 2005, we took samples of soil, interior and exterior dust, drinking water, and food from individual households, communal areas and markets. Additionally, water and sediment samples and fish were taken from the river. Interviews were conducted with householders to establish their age and body weight, general living conditions and sources of irrigation and drinking water. A food frequency questionnaire （FFQ） was designed to investigate the frequencies of consumption of several common regional food items, including fish from the fiver and/or local market. Human hair samples were also collected to estimate the mercury bioburden and to enable the validity of the modeling approach to be established. The paper expands on the main pathways of contamination and looks at linkages between exposure pathways and mercury concentrations found in human hair. Uncertainties inherent in risk analysis as well as their influence on the relative importance of different exposure routes are also discussed.  相似文献   

Changes to cadmium associations in canal sediments on drying and oxidation     

Samantha R. Cook John M. Chamock Andrew Parker 《中国地球化学学报》2006,25(B08):247-247

The mainly 19th Century canal system in the UK, largely managed by British Waterways, has been increasingly brought back into operation over the last few decades, and is now widely used for both leisure, and, increasingly, transport. Both initial and routine dredging of the canal sediment is carried out and these sediments are generally disposed of to land. Because many of the canals were connected with primary industries, their sediments can locally be significantly contaminated with heavy metals, and the behaviour of these metals under differing redox conditions, when introduced into a new environment （i.e., on land） is of importance for environmental risk-assessment purposes. Canal sediments are often rich in sulfidic mineral phases, and we have attempted to quantify the influence of these sulfidic phases on the release and retention of metals in dredged canal sediments, using a combination of traditional chemical techniques （e.g. sequential extraction） and X-ray absorption spectroscopy （XAS）. Sediment samples have been collected from urban fresh-water canals, one in the British Midlands and one in Northern France. It appears from XAS that Cd is largely associated with oxygen in air-dried sediment, and with sulphur in vacuum-dried sediment.  相似文献   

金沙江干热河谷区土壤侵蚀危险度评价——以云南元谋为例     

周红艺  熊东红杨忠 《山地学报》2006,24(B10):52-56

利用空间主成分分析方法，选取降水、坡度、植被、土地利用、土壤类型、人口、高程等作为评价指标，建立空间主成分评价模型Pi=0．78X1＋0．06X2＋0．05X3＋0．04X4，将研究区分为无险型、轻险型、危险型、强险型和极险型五种类型，较为准确地得到了危险度综合评价结果。因此，空间主成分分析模型，在土壤侵蚀危险程度评价方面的应用较为成功，是一种科学有效的研究方法。  相似文献   

The chromite deposits associated with ophiolite complexes, Southeastern Desert, Egypt： Petrological and geochemical characteristics and mineralization     

Gehad M. Saleh 《中国地球化学学报》2006,25(4):307-317

1 Introduction The association of massive Fe-Ni-Cu sulfides andchromite is a very unusual feature of podiformchromitites occurring in mantle tectonites of ophioliticcomplexes. It has only been described in theSoutheastern Desert, Egypt, where sulfides a…  相似文献   

中国辽宁早白垩世华夏翼龙（翼龙目：翼手龙亚目）一新种及古神翼龙科的系统分类     

吕君昌  金幸生  D.  M.  UNWIN  赵丽君  东洋一  季强 《地质学报》2006,80(6):791

根据中国辽西早白垩世九佛堂组一几乎完整头骨及头后骨骼建立古神翼龙类一新种：具冠华夏翼龙。具冠华夏翼龙以前上颌骨上具有一斧状矩形突起为特征，该突起的短轴垂直于前上颌骨的前边缘，除了该突起之外，其他的头骨特征比如鼻眶前孔的前边缘和前上颌骨的前边缘之间的吻部宽度均与季氏华夏翼龙的相似。华夏翼龙和中国的另一个古神翼龙类中国翼龙与古神翼龙共享有一些独特的头骨特征，并且这3个属看起来彼此之间的关系要比与其他神龙类密切的多。中国的古神翼龙（中国翼龙和华夏翼龙）具有相对长的头骨和弱的头骨嵴，而且似乎要比头骨短高和具有大的头骨嵴的古神翼龙原始。Tupuxuarids（Tupuxuara和Thalassodromeus）经常和古神翼龙类被放在古神翼龙科中，  相似文献   

工程测量平面坐标系统的建立   总被引：1，自引：0，他引：1  

郭红霞王军德  张俊山 《测绘技术装备》2005,7(3):31-33

本文讨论了地面长度投影到参考椭球面及椭球面长度投影到高斯平面所引起的长度变形,并结合实例给出了几种平面直角坐标系统的实现方法,对解决平面控制测量中的投影变形问题有很好的指导意义.  相似文献