The FLUXNET2015 dataset provides ecosystem-scale data on CO 2 , water, and energy exchange between the biosphere and the atmosphere, and other meteorological and biological measurements, from 212 sites around the globe (over 1500 site-years, up to and including year 2014). These sites, independently managed and operated, voluntarily contributed their data to create global datasets. Data were quality controlled and processed using uniform methods, to improve consistency and intercomparability across sites. The dataset is already being used in a number of applications, including ecophysiology studies, remote sensing studies, and development of ecosystem and Earth system models. FLUXNET2015 includes derived-data products, such as gap-filled time series, ecosystem respiration and photosynthetic uptake estimates, estimation of uncertainties, and metadata about the measurements, presented for the first time in this paper. In addition, 206 of these sites are for the first time distributed under a Creative Commons (CC-BY 4.0) license. This paper details this enhanced dataset and the processing methods, now made available as open-source codes, making the dataset more accessible, transparent, and reproducible.

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Serious grassland degradation is endangering the environment of the source regions of the Yangtze and Yellow Rivers (SRYYR). There is an urgent need to analyze and review the grassland resources, status of grassland degradation, factors causing grassland degradation, and measures for grassland protection and restoration so as to ensure sustainable development in the SRYYR. This review shows that: (1) The alpine meadow, one of the most important grassland types in the SRYYR, can be divided into four subtypes: typical alpine meadow, alpine swamp meadow, alpine steppe meadow and alpine shrub meadow. (2) There is approximately 357.13 × 104 ha degraded grassland in this area, which is 34.34% of the area of all the investigated grasslands in the SRYYR, and heavily degraded grasslands cover an area of 74.34 × 104 ha, approximately 20.82% of the degraded grasslands. (3) Alpine grassland degradation in the SRYYR follows the following sequence: non‐degraded grassland → lightly degraded grassland → moderately degraded grassland → heavily degraded grassland. (4) Grassland degradation in the SRYYR is caused by the integrated effect of anthropogenic and natural factors. The principal factors causing grassland degradation are thought to be long‐term overgrazing and the destruction by rodents that follows, and climate warming, which accelerates the grassland degradation process. (5) Some effective management practices (e.g. rodent and ruderal weed control, establishment of artificial grassland, rational management of grassland, and optimizing livestock structure) and integrated countermeasures for the restoration of degraded grasslands have been developed in the SRYYR.

A graphene–Au nanocomposite is prepared by a one‐step electrodeposition technique directly from a dispersion containing graphene oxide (GO) and HAuCl4. The electrodeposited graphene and Au particles are assembled into layered nanostructures. The coelectrodeposition technique can be extended to the fabrication of various graphene‐based composites.

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[1] The cold grasslands of the Qinghai-Tibetan Plateau form a globally significant biome, which represents 6% of the world's grasslands and 44% of China's grasslands. Yet little is known about carbon cycling in this biome. In this study, we calibrated and applied a process-based ecosystem model called Organizing Carbon and Hydrology in Dynamic Ecosystems (ORCHIDEE) to estimate the C fluxes and stocks of these grasslands. First, the parameterizations of ORCHIDEE were improved and calibrated against multiple time-scale and spatial-scale observations of (1) eddy-covariance fluxes of CO 2 above one alpine meadow site; (2) soil temperature collocated with 30 meteorological stations; (3) satellite leaf area index (LAI) data collocated with the meteorological stations; and (4) soil organic carbon (SOC) density profiles from China's Second National Soil Survey. The extensive SOC survey data were used to extrapolate local fluxes to the entire grassland biome. After calibration, we show that ORCHIDEE can successfully capture the seasonal variation of net ecosystem exchange (NEE), as well as the LAI and SOC spatial distribution. We applied the calibrated model to estimate 0.3 Pg C yr −1 (1 Pg = 10 15 g) of total annual net primary productivity (NPP), 0.4 Pg C of vegetation total biomass (aboveground and belowground), and 12 Pg C of SOC stocks for Qinghai-Tibetan grasslands covering an area of 1.4 × 10 6 km 2 . The mean annual NPP, vegetation biomass, and soil carbon stocks decrease from the southeast to the northwest, along with precipitation gradients. Our results also suggest that in response to an increase of temperature by 2°C, approximately 10% of current SOC stocks in Qinghai-Tibetan grasslands could be lost, even though NPP increases by about 9%. This result implies that Qinghai-Tibetan grasslands may be a vulnerable component of the terrestrial carbon cycle to future climate warming.

Ambipolar organic field‐effect transistors (OFETs) are produced, based on organic heterojunctions fabricated by a two‐step vacuum‐deposition process. Copper phthalocyanine (CuPc) deposited at a high temperature (250 °C) acts as the first (p‐type component) layer, and hexadecafluorophthalocyaninatocopper (F16CuPc) deposited at room temperature (25 °C) acts as the second (n‐type component) layer. A heterojunction with an interpenetrating network is obtained as the active layer for the OFETs. These heterojunction devices display significant ambipolar charge transport with symmetric electron and hole mobilities of the order of 10–4 cm2 V–1 s–1 in air. Conductive channels are at the interface between the F16CuPc and CuPc domains in the interpenetrating networks. Electrons are transported in the F16CuPc regions, and holes in the CuPc regions. The molecular arrangement in the heterojunction is well ordered, resulting in a balance of the two carrier densities responsible for the ambipolar electrical characteristics. The thin‐film morphology of the organic heterojunction with its interpenetrating network structure can be controlled well by the vacuum‐deposition process. The structure of interpenetrating networks is similar to that of the bulk heterojunction used in organic photovoltaic cells, therefore, it may be helpful in understanding the process of charge collection in organic photovoltaic cells.

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