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Inter-annual dynamics of grassland yield of the Three Rivers Headwaters Region of Qinghai-Tibet Plateau of China in 1988-2005 was analyzed using the GLO-PEM model, and the herbage supply function was evaluated. The results indicate that while grassland yield in the region showed marked inter-annual fluctuation there was a trend of increased yield over the 18 years of the study. This increase was especially marked for Alpine Desert and Alpine Steppe and in the west of the region. The inter-annual coefficient of variation of productivity increased from the east to the west of the region and from Marsh, Alpine Meadow, Alpine Steppe, Temperate Steppe to Alpine Desert grasslands. Climate change, particularly increased temperatures in the region during the study period, is suggested to be the main cause of increased grassland yield. However, reduced grazing pressure and changes to the seasonal pattern of grazing could also have influenced the grassland yield trend. These findings indicate the importance of understanding the function of the grassland ecosystems in the region and the effect of climate change on them especially in regard to their use to supply forage for animal production. Reduction of grazing pressure, especially during winter, is indicated to be critical for the restoration and sustainable use of grassland ecosystems in the region.

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The effects of ultraviolet (UV) irradiation on the degradation of Irgafos 168 and the migration of its two degradation products, 2,4-di-tert-butylphenol and tris(2,4-di-tert-butylphenyl)phosphate, from polypropylene (PP) were investigated. A blown film machine was used to extrude PP films containing Irgafos 168, the films were stored in the dark for 45 days, two UV treatments and sunlight exposure were applied to the films, and GC-MS was used for degradation and migration studies. Extrusion, storage, UV treatments, and sunlight exposure significantly affected concentrations of Irgafos 168 and the degradation products. 2,4-Di-tert-butylphenol was the major degradation product produced by UV irradiation, but tris(2,4-di-tert-butylphenyl)phosphate was the major degradation product produced by extrusion, storage, and sunlight exposure. The degradation products have no or little health risk, because migration study and threshold of toxicological concern (TTC) analysis show that experimental maximum migration of 2,4-di-tert-butylphenol and tris(2,4-di-tert-butylphenyl)phosphate are only 2 and 53% of the theoretical maximum migration amounts, respectively.

Obesity and associated metabolic disorders are worldwide public health issues. The gut microbiota plays a key role in the pathophysiology of diet-induced obesity. Glycerol monolaurate (GML) is a widely consumed food emulsifier with antibacterial properties. Here, we explore the anti-obesity effect of GML (1,600 mg/kg of body weight) in high-fat diet (HFD)-fed mice. HFD-fed mice were treated with 1,600 mg/kg GML. Integrated microbiome, metabolome, and transcriptome analyses were used to systematically investigate the metabolic effects of GML, and antibiotic treatment was used to assess the effects of GML on the gut microbiota. Our data indicated that GML significantly reduced body weight and visceral fat deposition, improved hyperlipidemia and hepatic lipid metabolism, and ameliorated glucose homeostasis and inflammation in HFD-fed mice. Importantly, GML modulated HFD-induced gut microbiota dysbiosis and selectively increased the abundance of Bifidobacterium pseudolongum. Antibiotic treatment abolished all the GML-mediated metabolic improvements. A multiomics (microbiome, metabolome, and transcriptome) association study showed that GML significantly modulated glycerophospholipid metabolism, and the abundance of Bifidobacterium pseudolongum strongly correlated with the metabolites and genes that participated in glycerophospholipid metabolism. Our results indicated that GML may be provided for obesity prevention by targeting the gut microbiota and regulating glycerophospholipid metabolism.

Investigating the spatial and temporal variance in productivity along natural precipitation gradients is one of the most efficient approaches to improve understanding of how ecosystems respond to climate change. In this paper, by using the natural precipitation gradient of the Inner Mongolian Plateau from east to west determined by relatively long-term observations, we analyzed the temporal and spatial dynamics of aboveground net primary productivity (ANPP) of the temperate grasslands covering this region. Across this grassland transect, ANPP increased exponentially with the increase of mean annual precipitation (MAP) (ANPP=24.47e 0.005MAP , R 2 =0.48). Values for the three vegetation types desert steppe, typical steppe, and meadow steppe were: 60.86 gm −2 a −1 , 167.14 gm −2 a −1 and 288.73 gm −2 a −1 respectively. By contrast, temperature had negative effects on ANPP. The moisture index (K ), which takes into account both precipitation and temperature could explain the spatial variance of ANPP better than MAP alone (ANPP=2020.34K 1.24 , R 2 =0.57). Temporally, we found that the inter-annual variation in ANPP (calculated as the coefficient of variation, CV) got greater with the increase of aridity. However, this trend was not correlated with the inter-annual variation of precipitation. For all of the three vegetation types, ANPP had greater inter-annual variation than annual precipitation (PPT). Their difference (ANPP CV/PPT CV) was greatest in desert steppe and least in meadow steppe. Our results suggest that in more arid regions, grasslands not only have lower productivity, but also higher inter-annual variation of production. Climate change may have significant effects on the productivity through changes in precipitation pattern, vegetation growth potential, and species diversity. grassland transect, spatial variance, temporal variance, temperature, precipitation gradient, Inner MongoliaTo effectively predict the impact of global change on terrestrial ecosystems, it is particularly necessary to understand the mechanism of how ecosystems respond to environmental factors [1,2] . As the basic process in ecosystems, aboveground net primary productivity (ANPP) strongly influences most ecosystem functions. It is of great importance in controlling nutrient flow, energy flow and carbon/water flux [3 -5] . Therefore, detecting how environmental change affects ANPP is one of the most important subjects in the field of global climate change research [1,2] .For most ecosystems, especially those in arid and semiarid environment, precipitation is the predominant climate factor controlling ecosystem processes. Precise understanding of the influence of precipitation on ANPP is very important in predicting climate change effects on ecosystems [6,7] . Moreover, investigating how ANPP varies temporally and spatially across a precipitation gradi-

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Scope: The gut microbiota plays an important role in the development of diet-induced obesity and metabolic syndrome. Glycerol monolaurate (GML), a widely consumed food emulsifier, is reported to promote metabolic disorder and gut microbiota dysbiosis in low-dose supplementation upon low-fat-diet feeding. However, little is known about whether GML produce the same effects in mice fed a high-fat diet (HFD). Methods and results: C57BL/6 mice are fed a HFD with or without GML supplementation (150, 300, and 450 mg kg −1 ) for 10 weeks. The results demonstrated that higher GML treatment (450 mg kg −1 ) ameliorates HFD-induced metabolic disorders, supported by prevented visceral fat deposition, improved hyperlipidemia, modulated hepatic lipid metabolism, and reduced serum proinflammatory cytokine, TNF-α. Additionally, all doses of GML attenuated circulating lipopolysaccharide load and insulin resistance. Notably, GML ameliorates HFD-induced gut microbiota dysbiosis, with increases in Bacteroides uniformis, Akkermansia, Bifidobacterium, and Lactobacillus and decreases in Escherichia coli, Lactococcus, and Flexispira. Spearman's correlation analysis indicates that these enriched specific genera are significantly associated with the metabolic improvements of GML. Conclusion: The findings identify the links between gut microbiota and GML-induced metabolic improvements, suggesting that the attenuation of HFD-induced metabolic disorders by higher GML supplementation may occur through targeting gut microbiota.