Application of bank protection structures for regulation of channel processes in the lower reaches of the Shu River

N.K. Yerzhanova, Zh.A. Mussin, A.D. Altynbekova — Fri, 10 Jul 2026 00:00:00 +0000

The article presents the application of bank protection structures for regulating channel processes in the lower reaches of the Shu River under conditions of high hydrological variability. The analysis is based on long-term hydrological observations conducted at the Tashutkul (Tasotkel) hydrological station over the period 1967–2022. A statistical assessment of annual maximum and mean discharges, including measures of variability, skewness, and exceedance probability, revealed the occurrence of rare but extreme flood events that significantly influence channel deformation and bank erosion in reaches composed of sandy–gravel alluvial deposits. A probabilistic hydrological analysis was applied to justify the design hydraulic loads acting on river training structures. Based on the identified hydrological and morphological risks, an improved prefabricated modular floating bank protection spur was developed for river engineering and channel regulation. The proposed structure provides adjustable permeability, promotes flow energy dissipation, and reduces local scour intensity under different flow conditions. The obtained results may be applied in the design and operation of adaptive bank protection structures for the lower reaches of the Shu River and other rivers characterized by pronounced channel instability and hydrological variability.

Geochemical Partitioning and Correlation of Rare Earth Elements, Thorium, and Uranium in Ion-Adsorption Clays from the Gemang Area, West Kelantan, Malaysia

S.C. Chang, N.A. Fendy, N.F. Shoparwe, A.H. Yusoff — Mon, 13 Jul 2026 00:00:00 +0000

This study aimed to determine the geochemical partitioning of total rare earth elements (ΣREE), thorium (Th), and uranium (U) in ion-adsorption clays (IACs) from the Gemang area, West Kelantan, Malaysia, and to evaluate how this partitioning may influence selective REE recovery with limited radionuclide mobilisation. An eight-step sequential extraction procedure was applied to representative saprolitic IAC samples, and the extracted fractions were analysed by ICP-OES. Pearson correlation analysis and principal component analysis (PCA) were further used to examine associations among ΣREE, Th, U, and selected major elements. The sequential extraction results showed that ΣREE were concentrated mainly in the ion-exchangeable fraction (average 22.0%), with additional contributions from the residual fraction (15.3%) and a notably high proportion in the primary sulphide step (53.4%). In contrast, Th and U were concentrated mainly in the primary sulphide fraction (54.4% and 41.3%, respectively) and the residual fraction (26.2% and 45.0%, respectively). Major elements such as Al, Fe, Mn, Ca, and Na showed distributions consistent with clay, oxide, and refractory mineral hosts. Statistical analysis indicated a positive association between ΣREE and Ca-Na, whereas Th and U were more closely associated with Fe-Mn-bearing fractions, indicating different host controls and different mobilisation behaviour. These results suggest that a recoverable REE pool is present in the exchangeable fraction, while most Th and U remain in less labile phases under the tested operational scheme. The study therefore provides geochemical evidence that mild ammonium-salt leaching may favour selective REE recovery from Gemang IACs while limiting the release of naturally occurring radioactive materials, although further mineralogical validation and dynamic leaching tests are still required.

Kompleksnoe Ispolzovanie Mineralnogo Syra = Complex use of mineral resources

Application of bank protection structures for regulation of channel processes in the lower reaches of the Shu River

Geochemical Partitioning and Correlation of Rare Earth Elements, Thorium, and Uranium in Ion-Adsorption Clays from the Gemang Area, West Kelantan, Malaysia