湘南稀土矿床的放射性特征及其对开采的影响

湘南主要稀土矿区的岩、矿石和稀土矿物的放射性特征表明，矿区放射性强度的高低与稀土总量无关，而与矿石的铀、钍含量密切相关；主要矿区的放射性对其开发与产品都没有影响，但长期接触对人体有一定危害。因此，开采时必须加强防护，防止放射性的长期照射，并选用无放射性的清洁饮用水，以保护人体健康。     

Use of fluorescein as a ground water tracer in brackish water aquifers

A drift and pumpback experiment was conducted in a brackish water sandfill. The sandfill was reclaimed from the sea in the eastern part of Singapore and contains sands with low organic and clay/silt contents. The high salinity in the ground water precludes the use of chloride and bromide as tracers in such an environment, and a field experiment was conducted to assess the viability of using fluorescein as a tracer in brackish water aquifers. Nitrate was used as a second tracer to serve as a check. Initial laboratory studies showed that fluorescence was unaffected over the range of electrical conductivity and pH of the ground water. Results from the field experiment show that fluorescein appears to behave conservatively.     

The myth of community and sustainable grassland management in China

Within national and international domestic academic circles, there are increasing calls for enhanced involvement of communities in formulating and implementing grassland management arrangements. In contrast to the current national policy of contracting grasslands to households, many scholars call for support for collective grassland use arrangements. Several reasons are given for increased recognition and support for community-based management of grasslands, including lower costs of exclusion and dispute resolution, economies of scale in herding and marketing, mitigation of environmental risk, and ensuring equitable access to grassland resources. One conclusion from this literature is that devolving authority for designing and implementing grassland management systems to communities would lead to more sustainable grassland use, a position that I term as the ‘myth of community.’ This paper presents the results of a study of grazing systems in two communities in Hongyuan County, Sichuan Province. Each community uses its grasslands collectively. However, the study found evidence of severe overgrazing, especially in winter pastures, suggesting that community-based management of grasslands is not necessarily sustainable. The paper discusses three potential policy innovations required to support sustainable grazing systems in China’s grassland areas: overcoming constraints in labor and land markets, and payments for environmental services that reward sustainable stocking levels.     

Human capital requirements in Singapore's international financial centre

International financial centres (IFCs) are regarded as important nodes in governing global flows of money and capital. With increased globalization and rapid technological changes, the rivalry among IFCs has further intensified competition for financial labour—as a concentrated pool of highly skilled finance workers in an open and flexible labour market is crucial to sustaining the competitive dynamics of these urban financial hotspots. This study investigates the importance of different skills and tasks in financial work. Based on surveys and interviews conducted among Singapore's IFC workers, the findings show that cognitive, interpersonal communication and managerial-leadership skills and tasks are more important in financial work, whereas programming, mathematics and systems-based skills are perceived to be less important. Additionally, a network visualization of finance occupational skills obtained from Singapore's national skills database reinforces the importance of cognitive and relational skills in that sector. Higher-order cognitive and relational skills are expected to become even more critical as the financial sector undergoes rapid digital transformation, reinforcing the importance of IFCs as agglomerations of skilled finance talent.     

Carbon Isotope Geochemistry of the Orinoco Basin

Stable carbon isotope ratios have been used to study the sources of particulate organic carbon (POC) and total dissolved inorganic carbon in the Orinoco Basin. The isotopic composition of total dissolved inorganic carbon shows a range of from -8·1 to -23·0 ppt, an indication of dominance of biological processes. The isotopic composition of POC exhibits a range of from -24·1 to -34·6 ppt with little seasonal variation. The isotopic evidence indicates that the POC is predominantly of terrestrial origin rather than a result of in situ planktonic production. The similarity of isotopic composition of POC and coastal sediments suggests that riverine organic detritus has been transported 30-50 km offshore in a direction parallel to the Orinoco river channel.     

山东矽卡岩型铁矿床充水特征及水害治理对策

笔者通过对山东矽卡岩型铁矿床的含水层结构类型、岩溶发育空间分布特征及矿床内外灰岩充水条件的归纳分析,总结了其不同的富水程度,探讨了矿坑水防治对策。     

东海放射虫甘葡萄虫科的一新属及其两新种

1958-1961年在东海陆棚区进行放射虫的调查研究时,发现甘葡萄虫科(Glycobotrydidae)的一新属及其两新种。     

The Second Modified Perpendicular Drought Index (MPDI1): A Combined Drought Monitoring Method with Soil Moisture and Vegetation Index

Since soil moisture and vegetation index are direct and important indicators for surface drought status, a new drought monitoring method (MPDI1) is developed in NIR-Red reflectance space. It is a combination of two satellite-derived variables—a soil moisture component using the Perpendicular Drought Index (PDI), and a vegetation component using the Perpendicular Vegetation Index (PVI). Enhanced Thematic Mapper Plus (ETM+) image and in-situ ground observation are introduced to validate the accuracy of the proposed method. Results indicate that MPDI1 is highly consistent to the in-situ ground observation with the coefficient of determination (R²?=?0.49) between MPDI1 and 5–20 cm mean soil moisture, which is slightly higher than the coefficient of determination (R²?=?0.42) between MPDI1 and 10 cm soil moisture. Compared with drought indices such as PDI and the Modified Perpendicular Drought Index (MPDI), MPDI1 provides quite similar trends for bare soil or lower vegetated surface, but it demonstrates a better performance in measuring densely vegetated surface. This paper concludes that MPDI1 provides correct and sufficient information on surface drought status in soil-plant continuum, which appears to have robust available and great potential for surface drought estimation in China and other countries.