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Phenolic compounds are toxic pollutants that are difficult to biodegrade. Electro-Fenton technique is one of the effective means to remove phenols. An Fe3O4-loaded carbon nanotube-modified nickel foam（Fe3O4/CNT/NF） particle electrode was prepared by the thermal solvent-coating-roasting method，which could generate both H2O2 and Fe2+ in the electrolytic system. A three-dimensional electrode electro-Fenton system was constructed with Fe3O4/CNT/NF as the particle electrode to degrade phenol，which has higher removal efficiency and lower energy consumption compared with the three-dimensional based on Fe3O4/NF and NF particle electrodes and two-dimensional electrode system. The reaction conditions were optimized，and the removal rate was 76.23% at degradation time of 60 min，plate spacing of 3.0 cm，Fe3O4/CNT/NF particles electrode dosage of 8.0 g/L，current of 350 mA，electrolyte concentration of 100 mmol/L，and initial pH of 4. The quenching test results showed that the hydroxyl radical（·OH） played a major role in the degradation process in this system. The electrode stability was excellent，and the phenol removal rate only decreased by 6.09% after six cycles.

Livelihood vulnerability assessment has become an important policy tool for identifying groups in need of immediate intervention. Based on survey data covering 427 households in the Hulunbuir Grasslands in northern China, an indicator-based livelihood vulnerability assessment system (LVAS) was established by combining the sustainable livelihood framework and the exposure–sensitivity–adaptation framework, which described the livelihood vulnerability of households across the household life cycle in terms of the dimensions of exposure, sensitivity, and adaptation. A multiple linear regression model was used to identify the key variables that determine livelihood vulnerability. The results show that the livelihoods of pastoral households in the Hulunbuir Grasslands are moderately vulnerable overall, with a high level of exposure, a medium level of sensitivity, and a low level of adaptive capacity. As the household life cycle progresses (from the starting period to the empty-nest period), the adaptive capacity of pastoral households gradually decreases, and their livelihood vulnerability increases. The variables that most exacerbate the vulnerability of pastoral households’ livelihoods in this region are policy–ecological risks, climate–disaster risks and socioeconomic risks, and the main ways to reduce vulnerability are to improve these households’ productive capital, diversify their sources of livelihood, and improve their access to information. The results of the study provide empirical support for similar settings in different regions worldwide that aim to achieve a “win–win” situation of ecological conservation and sustainable livelihood development.

The accumulation and ablation processes of seasonal snow significantly affect the land surface phenology in a mountainous ecosystem. However, the ability of snow to regulate the alpine land surface phenology in the arid regions is not well described in the context of climate change. The impact of snowpack changes on land surface phenology and its driving factors were investigated in the Tianshan Mountains using the land surface phenology metrics derived from satellited products and a snow dataset from downscaled regional climate model simulations covering the period from 1983 to 2015. The results demonstrated that the annual mean start of growing season (SOS) and length of growing season (LOS) experienced a significant (p < 0.05) decrease and increase with a rate of −2.45 days/decade and 2.98 days/decade, respectively. The significantly advanced SOS and increased LOS were mainly seen in the Western Tianshan Mountains and Ili Valley regions with elevations from 2500 to 3500 m a.s.l and below 3000 m a.s.l, respectively. During the early spring, the significant decline in snow cover fraction (SCF) could advance the SOS. In contrast, snowmelt amount and annual maximum snow water equivalent (SWE) have an almost equally substantial positive correlation with annual maximum vegetation greenness. In particular, the SOS of grassland was the most sensitive to variations of snow cover fraction during early spring than that of other vegetation types, and their strong relationship was mainly located at elevations from 1500 to 2500 m a.s.l. Its greenness was significantly controlled by the annual maximum snow water equivalent in all elevation bands. Both decreased SCF and increased temperature in the early spring caused a significant advance of the SOS, consequently prolonging the LOS. Meanwhile, more SWE and snowmelt amount could significantly promote vegetation greenness by regulating the soil moisture. The results can improve the understanding of the snow ecosystem services in the alpine regions under climate change. [ABSTRACT FROM AUTHOR]

This study investigates how the individual and combined effects of urbanization and irrigation affect summer climate using convection‐permitting regional climate model simulations with/without urbanization or irrigation over the Huang‐Huai‐Hai plain (3HP). We found that (a) In dramatic urban expansion areas, T2max, T2avg, and T2min increased by 0.53, 0.43, and 0.40°C, respectively. Urbanization influenced the net radiation (RN), sensible heat flux (H), latent heat flux (LE), and ground flux (GF) by 1.08, 9.58, −10.69, and 0.59 W/m2 (b) Over the irrigated area, T2max, T2avg, and T2min significantly decreased by −1.50, −1.30, and −1.16°C. The RN, LE significantly increased by 10.06 W/m2, 28.40 W/m2, while H and GF decreased by 19.44 and 1.19 W/m2. (c) The combined effect of urbanization and irrigation decreased T2max, T2avg, and T2min by −0.84, −0.77, and −0.71°C. The RN, LE significantly changed by 4.93 and 27.84 W/m2, while H and GF declined by 18.65 and 1.28 W/m2. (d) Urbanization significantly decreased the total precipitation by 0.04 mm/day, while irrigation and the combined effect increased the total precipitation by 0.12 and 0.16 mm/day. Urbanization and irrigation have more influence on the extreme precipitation than on the summer mean precipitation. (e) Specific humidity (Q) changes at high altitude (>2 km) are mainly controlled by thermodynamic changes, while at a low level, Q changes depended on the evapotranspiration, sea‐land breeze, and surface roughness. Key Points: The individual and combined impacts of urbanization and irrigation on summer climate were investigated using ALARO‐SURFEX firstly over 3HPUrbanization reduced rainfall by decreasing convective precipitation, while irrigation enhanced convective and large‐scale precipitationUrbanization has accelerated the warming tendency while irrigation processes have delayed the temperature trend to some extent [ABSTRACT FROM AUTHOR]