Summary1. Great efforts have been made to control soil erosion by restoring plant communities in degraded ecosystems world-wide. However, soil erosion has not been substantially reduced mainly because current restoration strategies lead to large areas of mono-specific vegetation, which are inefficient in reducing soil erosion because of their simple canopy and root structure. Therefore, an advanced understanding of how community functional composition affects soil erosion processes, as well as an improved restoration scheme to reduce soil erosion, is urgently needed. 2. We investigated the effect of community functional composition on soil erosion in restored semi-arid grasslands on the Loess Plateau of China. Community functional composition of 16 restored grasslands was quantified by community-weighted mean (CWM) and functional diversity (FD) trait values, which were calculated from nine plant functional traits of thirteen locally dominant plant species. Species richness and evenness were also measured. Soil erosion rates were measured using standard erosion plots. The multimodel inference approach was used to estimate the direction and the relative importance of these biodiversity indices in reducing soil erosion. 3. A robust and strong negative effect of functional divergence (FDiv) on soil erosion was found. The prevalence of particular trait combinations can also decrease soil erosion. The greatest control over soil erosion was exerted when the community mean root diameter was small and the root tensile strength was great. 4. Synthesis and applications: These findings imply that community functional diversity plays an important role in reducing soil erosion in semi-arid restored grasslands. This means that current restoration strategies can be greatly improved by incorporating community functional diversity into restoration design. We propose a trait-based restoration framework for reducing soil erosion, termed 'SSM' (Screening-Simulating-Maintaining). SSM aims to translate the target of community functional diversity into community assemblages that can be manipulated by practitioners. Based on this framework, a comprehensive procedure, highlighting functional diversity as the primary concern in determining optimal community assemblages, was developed to meet the pressing need for more effective restoration strategies to reduce soil erosion.

Abstract. Long-term climatic records are scarce in the northeast Asia for understanding the behavior of the East

Abstract. Long-term climatic records are scarce in the northeast Asia for understanding the behavior of the East Asian Winter Monsoon. Here we describe a 250-year February–April temperature reconstruction (TCBM) based on tree-ring widths of Korean Pines from the Changbai Mountain area, Northeast China. The reconstruction can account for 45.7% of the temperature variance in the instrumental period (1953 to 2001). Four cold events including 1784–1815, 1827–1851, 1878–1889 and 1911–1945, and two warm events of 1750–1783 and 1855–1877 were identified before the instrumental period. Four regime shifts were also detected at 1781, 1857, 1878 and 1989. Good agreements between TCBM and other temperature records of East Asia suggest that the reconstruction is of good reliability and captures the regional cold/warm events of East Asia. Moreover, TCBM shows negative correlations with the instrumental or proxy-based EAWM intensity records. The known weakening of the EAWM in the late 1980s is in agreement with the regime shift at 1989 in TCBM. These comparisons suggest that the February–April temperature reconstruction may be a good indicator of the EAWM intensity.

Although trait choice is crucial to quantify functional diversity appropriately, the quantitative methods for it are rarely compared and discussed. Meanwhile, very little is known about how trait choice affects ecological conclusions drawn from functional diversity measures. We presented the four methods of trait selection as alternatives to the ordination axis-based method, which directly identify a subset of key traits to represent the main variation of all the traits. To evaluate their performance, we compared the closeness of association obtained by different methods between species richness and functional diversity indices (FAD, FD, Q, FDis) in the six ecosystems. The evaluation was also benchmarked against the results obtained by calculating the possible indices using all the trait combinations (the complete search method). We found that the trait selection methods were potential alternatives to axis-based method to gain a mechanistic understanding of functional responses and effects of traits, while these methods as well as the axis-based method possibly use mismatched information to interpret the investigated ecosystem properties. Trait choice profoundly affected the ecological conclusions drawn from functional diversity measures. The complete search method should be used to assess the rationale of different trait choice methods and the quality of the calculated indices.

A simple and environmentally friendly material, CoFe2O4@SiO2–SH, was prepared successfully with CoFe2O4 nanoparticles coated by SiO2 which was further functionalized with thiol groups (–SH).

To enhance the ability to remove mercury(II) from aqueous media, an Fe 3 O 4 magnetic nanocomposite (PPy-GO) composed of polypyrrole (PPy) and graphene oxide (GO) was synthesized in situ and characterized via scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), X-ray photoelectron spectrometry (XPS), X-ray diffraction (XRD), Fourier transform-infrared spectroscopy (FT-IR), zeta potential analysis, vibrating sample magnetometer (VSM) and the Brunauer-Emmett-Teller (BET) method. The performance of the magnetic PPy-GO for adsorbing mercury(II) from water along with the effects of solution pH, adsorbent dosage, coexisting ions, reaction time and temperature were studied in detail. The adsorption kinetics, isotherms and thermodynamics were investigated in detail to gain insights into the adsorption process. The results show that the BET surface area of the magnetic PPy-GO reached 1737.6 m 2 g À1. The Langmuir capacity of the magnetic PPy-GO for mercury(II) adsorption was 400.0 mg g À1 at 300 K and pH 7 AE 0.1.After adsorption, the magnetic PPy-GO nanocomposite could be efficiently separated from water via a magnetic field. The adsorption process was endothermic and spontaneous and occurred in accord with the Langmuir and pseudo-second-order models. The overall adsorption of mercury(II) not only involved chemisorption, but was also partially governed by intra-particle diffusion. Data from the preliminary application of magnetic PPy-GO to remove heavy metals from real electroplating effluent indicated a high removal efficiency of over 99% for mercury(II). Finally, a possible adsorption mechanism was discussed. All data showed that the magnetic PPy-GO material is a promising adsorbent to remove mercury(II) from aqueous media.

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