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Two sections of the Xintiangou Formation were examined in the Yunyang area, Northeastern Sichuan Basin, China. One of them was systematically sampled from bottom to top. Palynology and geochemistry analyses were performed on 20 samples, and Paleoclimatic indicators were extracted. The sporopollen assemblage indicates arid and hot paleoclimate as a whole, and the geochemical index shows hot and humid paleoclimate. Combined with the analysis of sedimentary characteristics, it shows that the sedimentary period of the Xintiangou Formation in the study area is characterized by arid and hot paleoclimate as a whole, and there were fluctuations of relative moist and arid. The humid climate recorded by geochemical indicators may be the illusion that the unconsolidated sediments transported to the shore shallow lake zone experienced strong weathering. When studying the palaeoclimate characteristics of continental basins, it is necessary to analyze all kinds of palaeoclimate proxy indexes in combination with sedimentary facies, and there may be a deviation in using a single palaeoclimate proxy index to invert the palaeoclimate of continental basins. [ABSTRACT FROM AUTHOR]

Through an Australia-China climate change bilateral project, we analyzed results of 51-year global offline simulations over China using the Australian community atmosphere biosphere land exchange (CABLE) model, focusing on integrated studies of its surface energy, water and carbon cycle at seasonal, interannual and longer time-scales. In addition to the similar features in surface climatology between the CABLE simulation and those derived from the global land-surface data assimilation system, comparison of surface fluxes at a CEOP reference site in northeast China also suggested that the seasonal cycles of surface evaporation and CO2 flux are reasonably simulated by the model. We further assessed temporal variations of model soil moisture with the observed variations at a number of locations in China. Observations show a soil moisture recharge–discharge mechanism on a seasonal time scale in central-east China, with soil moisture being recharged during its summer wet season, retained in its winter due to low evaporation demand, and depleted during early spring when the land warms up. Such a seasonal cycle is shown at both 50- and 100-cm soil depths in observations while the model only shows a similar feature in its lower soil layers with its upper layer soil moisture varying tightly with rainfall seasonal cycle. In the analysis of the model carbon cycle, the net primary productivity (NPP) has similar spatial patterns as the ones derived from an ecosystem model with remote sensing. The simulated interannual variations of NPP by CABLE are consistent with the results derived from remote sensing-based and process-based studies over the period of 1981–2000. Nevertheless an upward trend from observations is not presented in the model results. The model shows a downward trend primarily due to the constant CO2 concentration used in the experiment and a large increase of autotrophic respiration caused by an upward trend in surface temperature forcing data. Furthermore, we have compared river discharge data from the model experiments with observations in the Yangtze and Yellow River basins in China. In the Yangtze River basin, while the observed interannual variability is reasonably captured, the model significantly underestimates its river discharge, which is consist with its overestimation of evaporation in the region. In the Yellow River basin, the magnitudes of the river discharge is similar between modeled and observed but its variations are less skillfully captured as seen in the Yangtze River region. [ABSTRACT FROM AUTHOR]

The authors reflect on the environmental challenges in China and the solutions to its deteriorating condition. According to the Ministry of Environmental Protection, all the seven major rivers in the country are polluted and that it is recommended for people to avoid contact with them. They argue that intensified mining of mineral resources is brought by economic growth but it also results to severe environmental problems.