Climate change and human activities are strongly influencing the eco‐hydrological processes of the Chinese Loess Plateau. It is challenging to investigate the spatiotemporal changes of water and sediment yields and identify their potential causes. In this study, we used the annual runoff index (WI) and specific sediment yield (SSY) derived from 58 hydrological stations to quantify the changes and attempted to explain their potential causes. The WI exhibited significant (P < 0.05) decrease ranging from −0.1 to −2.6 mm yr−1 during 1957–2012 in 44 sub‐catchments. Similarly, the SSY in 52 sub‐catchments reduced in a range between −2.86 and −636 Mg km−2 yr−1. The region of Toudaoguai–Longmen has extremely high SSY ranging from 8000 to 41 000 Mg km−2 yr−1 during 1957–1969. Budget analysis suggested that the area of Lanzhou–Toudaoguai contributed limited sediment but extracted large amount of water. The areas with negative SSY were increasing and mainly distributed along the mainstream of the Yellow River. The Loess plateau was becoming drier and warmer since the 1950s, whereas the intensive human activities including water withdrawal, soil and water conservation projects and the operation of dams and reservoirs are the dominant factors for the decline in WI and SSY on the Loess Plateau. Copyright © 2016 John Wiley & Sons, Ltd.

Urchin-like nickel particles and prickly nickel chains were selectively prepared by a facile low-temperature chemical reduction method at ambient conditions. The synthetic process involved the chemical reduction of nickel ions and the oriented growth of nickel nanocrystals under kinetic control independent of surfactants or external magnetic field. The branch length and the overall morphologies of the products could be tailored by properly tuning the process conditions and the component of the reaction solution. The magnetic properties of the products were studied as well and the results demonstrated that the products present ferromagnetic properties related to the corresponding microstructure. On the basis of a series of contrast experiments, the probable growth mechanism and fabrication process of the products were proposed. This work provided a facile and effective strategy to fabricate self-assembled nickel hierarchical structures with tunable morphologies.

In this work, elliptic single-crystalline α-Fe2O3 superstructures are prepared successfully by a facile hydrothermal method independent of surfactants or templates. The as-obtained products were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and high-resolution transmission electron microscopy (HRTEM). The elliptic superstructures are composed of nanorods with a mean diameter of ca. 40 nm and an average length of ca. 200 nm. By properly monitoring the component of the reaction system, the morphology of the α-Fe2O3 superstructures can also be tuned to be spherical (consist of nanosheets) and quasi spindle-like (consist of integrated irregular blocks). On the basis of a series of contrast experiments over time, the probable growth mechanism and fabrication process of the products were proposed. The magnetic and electrochemical properties of the as obtained α-Fe2O3 superstructures with different morphologies are investigated systematically. The results show that these properties are greatly influenced by the special structures of the products. This work provides an additional strategy to prepared self-assembled superstructures with tailored morphologies (both for the building units and the overall products) and properties.