贵州和四川盆地云量的气候研究

贵州和四川盆地是我国云量最多的地区,素有“天无三日晴”和“蜀犬吠日”之说,盆地西缘的雅安古时还有“雅州天漏”的谚语。从全球日照百分率分布推知,川黔地区也是世界上天气最阴沉的地区之一。川黔之阴一向为国内外气象界所注意,本文根据1951—1980     

Seasonal variations in river discharge and nutrient export to a Northeastern Pacific estuary

Seasonal variations in dissolved nitrogen and silica loadings were related to seasonal variability in river discharge. Dissolved nutrient concentrations measured weekly at three stations in the Yaquina River, Oregon from 1999 through 2001, and then monthly in 2002 were used as the basis for developing a nutrient loading regression as part of a larger agency program for evaluating nutrient processes. Because realistic models of nutrient transport require dense data sets to capture both long and short term fluctuations in nutrient concentrations, data at one freshwater station also were collected hourly for the same years using an in-stream monitor.The effects of storm events on dissolved nutrient transport were examined during three storms, including one in a high rainfall-discharge year, and two in average years, one of which followed a drought year. During the drought year (WY2001), total dissolved nitrate input was considerably less than in wetter years. Dissolved nitrate concentrations, however, were unusually high in the first winter storm runoff after the drought. The freshwater dissolved nitrate nitrogen loads varied from 40,380 kg day⁻¹ during a high-flow storm event to 0.11 kg day⁻¹ during late summer, low flow conditions. Dissolved silica dynamics differed from those of nitrate because during storm events, silica concentrations in the Yaquina River decreased to near zero at the storm height, probably due to dilution by near surface or overland flow, and later recovered.During the time interval studied, over 94% of the dissolved nitrate and silica were transported from the watershed during the winter months of greater rainfall, indicating that seasonality and river flow are primary factors when considering nutrient loadings from this watershed system.     

黔北遵义团溪铝土矿勘探网密度探讨

以黔北遵义团溪铝土矿后槽矿区一矿块为例,用50m×50m工程间距进行施工成果与100m×50m和100m×100m工程间距施工成果,对其矿体厚度、矿体形态、主要化学成分含量及储量变化进行分析对比,以探寻此类矿床应如何选择工程间距,才能更合理准确地对矿体进行圈定控制,以满足矿山开采设计的要求。通过资料分析对比认为,对黔北喀斯特型沉积铝土矿进行勘查而言,以≤50m×50m工程间距控制矿体并求取储量,效果较为理想。     

贵州鹅项水库沉积物特征及其土壤侵蚀的意义

对位于贵州西南部非喀斯特丘原区的鹅项水库中取得的一沉积物样芯（EX-1）做了¹³⁷Cs,TOC,C/N和粒度分析以及矿物磁性测量。通过对这些分析和测量结果进行解译,推测了在过去的45年（1960～2005年）中这一水库的汇水流域内土壤侵蚀强度的相对变化。在这45年中,鹅项水库流域的土壤侵蚀经历了由弱到强再持续减弱的一个过程。将这一推测结果与流域内降水数据和土地利用/覆被变化资料数据相结合,探究了该流域土壤侵蚀强度变化的原因。与贵州西南部典型喀斯特流域的情况相比,在鹅项流域内,土地利用/覆被变化情况对土壤侵蚀强度的影响相对次要,而降水对土壤侵蚀强度变化的影响则更为重要。这可能主要因为与典型喀斯特流域相比,鹅项流域的土层较厚、植被覆盖较好。     

贵州中东部剩余重力异常与区域矿产分布关系

重点研究1:20万剩余重力异常,结合航磁、物性、地质等资料,初步圈定区内隐伏、半隐伏岩浆岩体,对研究与重力异常、岩体分布关系密切的矿产的时间、空间分布及其成因,有一定参考价值和指示意义。     

贵州省排庭金矿地质特征与成因分析

排庭金矿是贵州三都——丹寨锑、汞、金成矿带上,继苗龙锑-金矿、宏发厂汞-金矿后首次发现的产于中下寒武统独立型的微细浸染型金矿,其矿体受断裂构造、地层、岩性等因素控制,矿床规模为中型。对该矿床的地质特征及成因进行总结和分析,对于华南褶皱带与扬子准地台过渡带寻找寒武纪地层中的微细浸染型金矿具有重要的借鉴和指导意义。     

黔北后槽下石炭统含铝岩系的粘土矿物

为揭示黔北下石炭统含铝岩系的沉积环境,本文利用贵州遵义县后槽TC718剖面系统试样的粘土矿物进行x一射线衍射测试及特征分析。含铝岩系粘土岩与下伏桐梓组粘土页岩在矿物组合和成分上均有明显的差异,水云母的结晶度指数、开形指数在剖面纵向上有三个变化拐点：一是含铝岩系与下伏桐梓组粘土页岩分界处;二是含铝岩系上、下段的接触带;三是含铝岩系顶部含炭质粘土岩出现的临界面。其变化特征表明,本区下石炭统含铝岩系粘土岩段为海相或海陆过渡相,铝质岩段为残积一坡积相,顶部为大陆湖沼相;下奥陶统桐梓组页岩段为海相。     

贵州中三叠统烂泥沟金矿有机质的初步研究

烂泥沟金矿是以浊积岩为容矿岩石的微细浸染型金矿。有机岩石学分析表明,矿石与围岩中干酪根类型无明显差别,同属腐泥-腐植型。与围岩相比,矿石中干酪根成熟度(R₀=2.74%-3.06%)和含金性(6.15-24.8μg/g)均较高;干酪根总含金量在全岩中所占的比例是围岩高于矿石。氯仿沥青“A”的检测说明,矿石样品中可溶性有机质形成于强还原和高盐度环境,沥青质和含硫有机化合物发育。研究认为,干酪根含金性与碳的活化有关;不饱和的有机基因对金的动一定转换可能具有重要意义。     

Soil quality changes in land degradation as indicated by soil chemical, biochemical and microbiological properties in a karst area of southwest Guizhou, China

Not only the nutritional status and biological activity but also the soil ecological functioning or soil health has been impacted profoundly by land degradation in the karst area of southwest China where the karst ecosystems are generally considered as extremely vulnerable to land degradation under intensified land-use changes. The objectives of this study are to elucidate the changes in overall soil quality by a holistic approach of soil nutritional, biological activity, and soil health indicators in the karst area as impacted by intense cultivation and vegetation degradation. Topsoil samples were collected on selected eco-tesserae in a sequence of land degradation in a karst area of southwest Guizhou in 2004. The soil nutrient pools of organic carbon (C_org), extractable extracellular carbon (C_ext), total soil nitrogen (N_t), alkali-hydrolyzable nitrogen (N_ah), total phosphorus (P_t), available phosphorus (P_a) were analyzed by wet soil chemistry. The soil biological properties were studied by means of measurements of microbial biomass carbon (both by fumigation–extraction, FE-C_mic, and by calculation from substrate-incubation respiration, SIR-C_mic) of respiration [respiration without addition of substrates, basal respiration (BR), and potential respiration (PR) with substrate-incubation] and of soil enzyme activities (invertase, urease, and alkaline phosphatase). Soil health status was assessed by simple indices of C_mic/C_org and BR/C_mic in conjunction with bacterial community structures determined by polymerase chain reaction and denaturing gradient gel electrophoresis. While the nutritional pool parameters, such as C_org and C_ext, described basically the changes in soil life-supporting capacity with cultivation interference and vegetation declined, those parameters of biological activity such as FE-C_mic, SIR, and SIR-C_mic as well as bacterial community structures measured by molecular method evidenced well the changes in soil functioning for ecosystem health with the land degradation.     

黔西南高砷煤的元素地球化学特征

通过分析黔西南高砷煤的元素地球化学特征,探索高砷煤中微量元素、稀土元素的地球化学行为,从而揭示了高砷煤的形成机理。分析表明,高砷煤与非高砷煤在微量元素含量方面存在较大差异,金、汞、铊矿石与龙潭煤系中的砷具有同源性,龙潭煤系页岩与峨眉山玄武岩在稀土元素组成上具有继承性。