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851.
852.
福建省前峰硫 多金属矿的形成具明显的层控特征。矿体赋存于上石碳统─下二叠统船山组及栖霞组灰岩中,成矿作用是多期叠加的、复杂的。在与生物礁有关的沉积阶段,生物吸附提供了主要硫源,后期热液改造对沉积成矿作用有着继承性,区域动力变质热液及其派生的分泌、分异成矿热液,以及与岩浆有关的热液多期次参与矿床的变质改造,而这些热液活动均与政和 大埔深大断裂有关。 相似文献
853.
The effluent contamination of groundwater at two industrial sites at Visakhapatnam, India, was studied using factor analysis.
Thirty groundwater samples near a zinc smelter plant and 19 from the polymers plant were analyzed for specific conductance,
chloride, bicarbonate, sulfate, calcium, magnesium, sodium, and potassium. The data were subjected to R-mode factor analysis
and the factor scores transferred to areal maps. While magnesium and sulfate are the dominant contaminants at the zinc site,
sodium, chloride, and bicarbonate from the effluent are affecting groundwater in the polymers area. Contour maps for each
factor suggest the areal extension of the contaminants.
Received: 1 March 1995 · Accepted: 18 September 1995 相似文献
854.
P. K. Mukhopadhyay G. Lajeunesse A. L. Crandlemire 《International Journal of Coal Geology》1996,32(1-4)
Systematic changes in mineralogy, enrichment and depletion of selected elements, and mineralogical speciation of selected elements in fly ash and bottom ash samples from the Lingan Power Plant were compared to run-of-mine and pulverized feed coal from the Sydney coalfield, Nova Scotia, eastern Canada. The analytical techniques used were an electron microprobe equipped with energy and wavelength X-ray dispersive spectrometers, X-ray diffraction, neutron activation, scanning electron microscopy with energy dispersive X-ray and incident light petrography. Three types of glasses (Fe/O-rich, Fe/Al/Si/O-rich and or Al/Si/O-rich) were identified in the combustion residues; they were formed as a result of the interaction of melted pyrite and clay minerals. Compared to the feed coal, most elements were enriched 10 to20 times in the fly ash. The concentration of the elements in both the fly ash and bottom ash are comparable to coal ash that is generated by the low temperature asher in the laboratory. Some chalcophile elements such as arsenic and lead occurred as a solid solution in pyrite in the feed coal and were concentrated in the float fraction (density: <2.81 g/cm3) of the fly ash with non-crystalline Fe-oxides. X-ray mapping of arsenic in the fly ash and bottom ash indicates that arsenic was evenly distributed as oxide within the Fe/O- and Fe/Al/Si/O-rich glass and crystalline phases in the fly ash, possibly in solid solution. Arsenic is associated with Fe/O and Fe/S crystalline phases in the bottom ash. 相似文献
855.
José M. Gómez 《Journal of Arid Environments》1996,33(4):425-437
In this paper the effect of herbivory on the seed production ofMoricandia moricandioides(Cruciferae), an annual species living in arid habitats of south-eastern Spain, is analysed. Firstly, the flowering and fruiting phenology and the composition and structure of the pollinator guild is described, in order to compare the overall effect of mutualistic speciesvs. that of antagonistic species onM. moricandioidesseed production. The loss of female reproductive success due to each herbivore species attacking the plant is then quantified, in an attempt to differentiate the effects on plant seed production of each herbivorous species. The results indicate that only antagonistic organisms interacting withM. moricandioidesinfluenced the female fitness of this plant species. In fact, pollinator abundance or activity did not correlate with the number of seeds dispersed by the plants. In addition, of all the herbivore species, only sheep activity significantly influenced seed production ofM. moricandioidesindividuals, the effect of the remaining crucivorous herbivores being cancelled by the stronger herbivory of sheep. The results of this study suggest that herbivory by sheep, in addition to decreasing the seed production ofM. moricandioides, could be an important determinant of the current distribution pattern of this crucifer species on the ramblas of the Baza basin. 相似文献
856.
Highland barley is an important staple food in the Tibet, and the Tibetan Plateau is experiencing obvious climatic warming. However, few studies have examined the warming effects on highland barley growth and biomass allocation under conditions of controlled experimental warming. This limits our ability to predict how highland barley will change as the climate changes in the future. An experiment of field warming at two magnitudes was performed in a highland barley system of the Tibet beginning in late May, 2014. Infrared heaters were used to increase soil temperature. At the end of the warming experiment (September 14, 2014), plant growth parameters (plant height, basal diameter, shoot length and leaf number), biomass accumulation parameters (total biomass, root biomass, stem biomass, leaf biomass and spike biomass), and carbon and nitrogen concentration parameters (carbon concentration, nitrogen concentration, the ratio of carbon to nitrogen concentration in root, stem, leaf and spike) were sampled. The low- and high-level experimental warming significantly increased soil temperature by 1.52 and 1.98 °C, respectively. Average soil moisture was significantly decreased by 0.03 m3 m-3 under the high-level experimental warming, while soil moisture under the low-level experimental warming did not significantly change. The low- and high-level experimental warming did not significantly affect plant growth parameters, biomass accumulation parameters, and carbon and nitrogen concentration parameters. There were also no significant differences of plant growth parameters, biomass accumulation parameters, and carbon and nitrogen concentration parameters between the low- and high-level experimental warming. Our findings suggest that the response of highland barley growth, total and component biomass accumulation, and carbon and nitrogen concentration to warming did not linearly change with warming magnitude in the Tibet. 相似文献
857.
四川大麦地泥盆纪煤的物质组成与早期陆生植物生态的关系 总被引:1,自引:0,他引:1
大麦地一带中泥盆统产有数据透镜状煤层,其中角质体含量一般〉75%,而且不同富煤点煤中角质体类型,含量,结构特点都不相同,存在明显的分异现象。这种分异现象反映出早期陆生植物对环境的适应和生态特点,是聚煤环境,植物类型和生态等因素综合作用的结果。 相似文献
858.
河南登封煤田下石盒子组植物古生态学研究 总被引:3,自引:0,他引:3
根据系统的植物化石采集,详细的古生态样方测量和等离子光谱定量分析,对河南登封煤田早二叠世晚期下石盒子组植物古生态进行了细致地研究,探讨了该区早二叠世晚期植物化石埋藏特征,沉积环境特征和植物古群落特征,建立了一个早二叠世晚期植物群落-Chiropteris reniformis湿生植物群落。 相似文献
859.
860.