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Graphical abstract Highlights • Isotopic signatures of REY ores in S Primorye evidence its heterogeneous nature. • The ore metals are derived from the upper Earth's crust. • Major factors of the mineralization are meteoric waters and CO 2 of mantle origin. • Deep-seated faults inside and around coal basins control localization of the ores. Abstract The paper is based on stable isotopic analyses (C, O, H) first obtained for the rare earth elements + yttrium mineralization of South Primorye and Southwest Japan in addition to recent exploration data and some K-Ar and U-Pb datings. The analyzed minerals include hydrous carbonates and clay minerals that are hosted by argillized (weathered) shale, granite, mafic rocks, and semi-lithified sediments of various (from Cambrian to Late Cenozoic) age. The data distinctly evidence that a major agent of rare metal leaching from the host rocks and their redistribution inside the lignite-bearing sediments and weathered crust was meteoric water. Its moderately acidic character was due to carbon dioxide flowing up from the mantle through faults associated with the lignite basins, in addition to organic matter and sulfides disseminated in the host rocks. Concentrated precipitation and sorption of rare earths and yttrium from the evolved meteoric water were probably caused by their neutralization or even alkalization that had resulted from CO 2 release near the surface. The previous Sr-Nd isotopic data for lanthanite-(Nd) from South Primorye indicate the upper Earth's crust origin of the ore metals. Thus, both endo- and exogenous factors significantly influenced the studied mineralization in Primorye. Juvenile CO 2 made a key contribution to meteoric waters allowing them to mobilize and redistribute ore components in the near-surface conditions. The deep-seated faults cross-cutting and bordering the lignite basins and providing the necessary conduits for the upflows of carbon dioxide are suggested to control localization of the studied mineralization. [ABSTRACT FROM AUTHOR]

A regional coupled soil–vegetation–atmosphere model is used to study changes and interactions between climate and the ecosystem in East Asia due to increased atmospheric CO[sub 2] . The largest simulated climate changes are due to the radiative influence of CO[sub 2] , modified slightly by vegetation feedbacks. Annual precipitation increases by about 20% in coastal areas of northern China and in central China, but only by 8% in southern China. The strongest warming of up to 4°C occurs in summer in northern China. Generally, the climate tends to be warmer and wetter under doubled CO[sub 2] except for inland areas of northern China, where it becomes warmer and drier. Most of the changes discussed in this paper are associated with changes in the East Asian monsoon, which is intensified under doubled CO[sub 2] . The largest changes and feedbacks between vegetation and climate occur in northern China. In some coastal and central areas around 40°N, temperate deciduous forests expand northward, replacing grassland due to warmer and wetter climate. Evergreen taiga retreats in the coastal northeast, causing extra cooling feedback due to less snow masking. The largest changes occur in extensive inland regions northward of 40°N, where deserts and shrub land expand due to warmer and drier conditions, and water supply is a critical factor for vegetation. These northern inland ecosystems experience considerable degradation and desertification, indicating a marked sensitivity and vulnerability to climatic change. [ABSTRACT FROM AUTHOR]