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Plant phenology under changing climate is a critical factor controlling terrestrial vegetation productivity. However, large uncertainties exist due to different data sources and phenological parameter extraction methods. In this study, we took advantage of a suite of long-term field observational data in northern grassland of China to investigate the drivers of phenological shifts and their effect on the maximum aboveground net primary productivity (ANPPmax) across four representative grassland types during 1984–2017. Results showed that drivers of phenological events (i.e., start (SOS), end (EOS), and length (GSL) of the growing season) with warming influence dramatically differed among grassland types, indicating that the synergistic effect of temperature and precipitation should be highlighted. For temperate desert steppe and alpine meadow, GSL of dominant species was both significantly lengthened with temperature rising with averaged 0.94 days year−1 (P < 0.001) and 1.15 days year−1 (P < 0.001), respectively, while for typical temperate grassland, GSL was considerably shortened by an average of 0.58 days year−1 (P < 0.01) as a result of water deficit caused by sharp warming and precipitation decreasing in summer and autumn. For most grassland types in our study, both SOS and GSL were significantly correlated with ANPPmax under different precipitation gradients with SOS advanced and GSL extended leading to higher ANPPmax. Only the typical temperate grassland presents a relatively poor correlation between phenological events and productivity. Furthermore, compared with GSL, ANPPmax was more sensitive to the advancement of SOS for every 1-day phenological change. However, the effect of EOS on ANPPmax across the four grassland types was much weaker and unstable. There were spatial response differences between ANPPmax and phenological transition events, with the temperate meadow grassland tending to be more sensitive compared with three other grassland types. [ABSTRACT FROM AUTHOR]

Biological carbon pumping (BCP) is a key process in which dissolved inorganic carbon in terrestrial aquatic ecosystems is utilized by aquatic autotrophs for photosynthesis and transformed into autochthonous organic matter (AOC). However, the mechanisms underlying BCP and the amount of generated AOC deposited effectively, are still poorly understood. Therefore, we conducted a systematic study combining modern hydrochemical monitoring and a sediment trap experiment in Fuxian Lake (Yunnan, SW China), the second-deepest plateau, oligotrophic freshwater lake in China. Temperature, pH, EC (electrical conductivity), DO (dissolved O2), [HCO3−], [Ca2+], SIc, partial CO2 (pCO2) pressure, and carbon isotopic compositions of HCO3− (δ13CDIC) in water from Fuxian Lake all displayed distinct seasonal and vertical variations. This was especially apparent in an inverse correlation between pCO2 and DO, indicating that variations of hydrochemistry in the lake water were mainly controlled by the metabolism of the aquatic phototrophs. Furthermore, the lowest C/N ratios and highest δ13Corg were recorded in the trap sediments. Analyses of the C/N ratio demonstrated that the proportions of AOC ranged from 30% to 100% of all OC, indicating that AOC was an important contributor to sedimentary organic matter (OC). It was calculated that the AOC flux in Fuxian Lake was 20.43 t C km−2 in 2017. Therefore, AOC produced by carbonate weathering and aquatic photosynthesis could potentially be a significant carbon sink and may have an important contribution to solving the lack of carbon sinks in the global carbon cycle. [ABSTRACT FROM AUTHOR]

We developed a panel of multiplex quantitative real-time reverse transcription polymerase chain reaction (mqRT-PCR) assay consisting of seven internally controlled qRT-PCR assays to detect 16 different respiratory viruses. We compared the new mqRT-PCR with a previously reported two-tube mRT-PCR assay using 363 clinical sputum specimens. The mqRT-PCR assay performed comparably with the two-tube assay for most viruses, offering the advantages of quantitative analysis, easier performance, lower susceptibility to contamination, and shorter turnaround time in laboratories equipped with conventional real-time PCR instrumentation, and it could therefore be a valuable tool for routine surveillance of respiratory virus infections in China. [ABSTRACT FROM AUTHOR]

The occurrence of rice high-temperature damage (HTD) has increased with global warming. Cultivation of rice is seriously affected by the HTD in the middle and lower reaches of the Yangtze River, which directly affects food security in this region and in the whole of China. It is important to monitor and assess crop HTD using satellite remote sensing information. This paper reviews the recent development of monitoring rice HTD using optical remote sensing information. It includes the use of optical remote sensing information to obtain the regional spatial distribution of high temperatures, mixed-surface temperature retrieval for rice fields based on mixed decomposition information, the development of field and thermal infrared testing and modeling, and the satellite/ground-based remote sensing coupled method for monitoring rice HTD. Finally, the prospects for monitoring crop HTD based on remote sensing information are summarized. [ABSTRACT FROM AUTHOR]