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The identification of the Shandong loess provenance adjacent to the floodplain of the Yellow River external the Loess Plateau is very important for revealing the path of dust accumulation and paleoenvironment, which has aroused widespread concern. In this study, the clay-size(< 5•m) minerals and major elements composition of bulk samples and of two grain-size fractions (< 20•m and 20~63•m) were analyzed in order to determine the provenance of the LongQiaoCun(LQC) loess in the Central Shandong based on comparisons with loess from the Chinese Loess Plateau and with Yellow River sediments. Statistical analysis of the sedimentary clay-size minerals reveals that LQC loess deposits in the Central Shandong adjacent to the floodplain of the Yellow River were not blown directly from the northern deserts as is the case of loess deposits in the Chinese Loess Plateau. and the Yellow River sediments may be related to erosion from the Loess Plateau. The difference in relatively immobile major element ratios of TiO2 /Al 2O3 and K 2O/Al 2O3 of the < 20•m and 20 ~ 63•m fractions affirm that sediments exposed during glacial periods in the North China fluvial plain, including the floodplain of Yellow River, were the major dust source as the statistical analysis of the sedimentary clay-size minerals has concluded.

Quaternary aeolian silts in the Chinese Loess Plateau (CLP) has long been regarded as a product of sand ablation during the process of transportation originally from sandy deserts of northern China and Mongolian Gobi deserts driven by winter monsoon. Recently, this traditional idea was challenged by a new idea that aeolian silts in the CLP were emitted from fluvial sediments in the middle reaches of the Yellow River which was originally transported from the Tibetan Plateau ascribed to intensified Asian summer monsoon. We systematically determined the origin of Quaternary aeolian silts in a 318-m-thick loess/palaeosol sequence by using U–Pb age spectrum of detrital zircon grains, and compared it with Quaternary fluvial sediments on the Yellow River terraces in Lanzhou, western CLP. The aeolian silts were originated from Qilian Mountains in Northeastern Tibetan Plateau since 1.4 Ma with exception in the intervals of 1.02–0.93 Ma, ∼0.75 Ma and ∼0.06 Ma when aeolian silts were originated from Gobi-Altai Mountains. In contrast, Quaternary fluvial sediments of the Yellow River were mainly originated from Songpan block south to the Qilian Mountains. We propose that the Quaternary aeolian silts in western CLP were emitted and transported by winter wind circulation from piedmonts of the Qilian Mountains more than by the Yellow River from the Songpan block to the south. This study promotes the recognition in terms of the source of the Quaternary aeolian silts in western China. • Quaternary aeolian silts in western CLP originated from Qilian Mountains. • Quaternary fluvial sediments of Yellow River originated from Songpan block. • Quaternary aeolian silts were less reworked from the Yellow River than from Qilian Mountains. [ABSTRACT FROM AUTHOR]

To solve the disposal problems of solid wastes, dehydrated sewage sludge and Yellow River sediments were tested as components for production of ultra-lightweight ceramsite. The effects of Yellow River sediments addition on the characteristics of ceramsite were investigated. Ceramsite with different Yellow River sediments additions was characterized using thermal analysis, X-ray diffraction, morphological structures analyses, pore size distributions and porosity analyses. Chemical components, especially ratios of SiO + AlO/Flux, were used to explain the glassy shell formation, physical properties and pores distribution of ultra-lightweight ceramsite; physical forces for instance expansion force and frictional resistance which combined with SiO + AlO/Flux ratios were used to explain the bloating mechanism. Results showed that the maximum addition of Yellow River sediments for making ultra-lightweight ceramsite was 35%. Macropores (between 0.226 μm and 0.554 μm) of ultra-lightweight ceramsite were dominant in the pore structures of ultra-lightweight ceramsite and its porosity was up to 67.7%. Physical force of expansion force was constant with the variation of Yellow River sediments content and physical force of frictional resistance was decreased with the increase of Yellow River sediments addition. The relationship between expansion and frictional resistance could determine the expansion rate of ceramsite. Larger pores inside the ceramsite bodies could be obtained as Yellow River sediments additions ranged from 10% to 30%. Ceramsite with higher Yellow River sediments additions of 40% (SiO + AlO/Flux ratios ⩽ 4.25) became denser and have lower porosity. Crystal components analysis proved that the sintering process made some components of raw materials transfer into other crystals having better thermostability. [ABSTRACT FROM AUTHOR]

With continuous population growth and decreasing cultivated land area, China's food security is greatly threatened. Additionally, coal mining in China is primarily underground mining, which causes land subsidence and destroys existing cultivated land. This effect aggravates the contradiction between a growing population and a shrinking area of cultivated land. The purpose of this study was to introduce a method of filling reclamation with Yellow River sediments to restore farmland and realize the sustainable utilization of cultivated land. The properties of the soil and crop yields in reclaimed farmland were assessed. This study examined farmland reclaimed with Yellow River sediments at an experimental site located in Jining City, Shandong Province, China. Filling reclamation procedures with Yellow River sediments were applied. The reclaimed farmland (RF) and unaltered farmland (CK) were continuously monitored for three years, and the soil was sampled six times. A total of 180 soil samples were collected from RF and CK. The soil properties were measured at three depths: 0–20 cm, 20–50 cm, and 50–80 cm. Crop yields were monitored regularly. The results indicate that filling reclamation with Yellow River sediments is an effective method for restoring farmland. The RF and CK soils were weakly alkaline, non-saline soils. The RF soil was suitable for the growth of local crops. With an increasing number of farming years, both the quality of cultivated land and crop yields have increased. Therefore, filling reclamation with Yellow River sediments is an effective way to realize the sustainable utilization of cultivated land. [ABSTRACT FROM AUTHOR]