Anthropogenic and climate impacts on carbon stocks of grassland ecosystems in Inner Mongolia and adjacent region.

Up to date, most studies reported that degradation is worsened in the grassland ecosystems of Inner Mongolia and adjacent regions as a result of intensified grazing. This seems to be scientific when considering the total forage or total above-ground biomass as a degradation indicator, but it does not hold true in terms of soil organic carbon density (SOCD). In this study, we quantified the changes of grassland ecosystem carbon stock in Inner Mongolia and adjacent regions from the 1980s to 2000s and identified the major drivers influencing these variations, using the National Grassland Resource Inventory and Soil Survey Dataset in 1980s and the Inventory data during 2002 to 2009 covering 624 sampling plots concerned vegetal traits and edaphic properties across the study region. The result indicated that the above-, below-ground and total vegetation biomass declined from the 1980s to 2000s by ∼ 10 %. However, total forage production increased by 6.72 % when considering livestock intake. SOCD remained stable despite a 67 % increase in grazing intensity. A generalized linear model (GLIM) analysis suggested that an increase in grazing intensity from the 1980s to 2000s could only explain 1.04 % of the total biomass change, while changes in precipitation and temperature explained 17.7 % (p < 0.05) of total vegetation biomass (TVB) change. Meanwhile, SOCD change during 1980s - 2000s could be explained 10.08 % by the soil texture (p < 0.05) and <1.6 % by changes in climate and livestock. This implies that the impacts of climate change on grassland biomass are more significant than those of grazing utilization, and SOCD was resistant to both climate change and intensified grazing. Overall, intensified grazing did not result in significant negative impacts on the grassland carbon stocks in the study region during the 1980s and 2000s. The grassland ecosystems possess a mechanism to adjust their root-shoot ratio, enabling them to maintain resilience against grazing utilization.

High-frequency monitoring of China's green growth-at-risk.

With industrialization and urbanization, China faces enormous challenges from energy security and environmental issues. To address these challenges, it is imperative to establish a green accounting system for economic growth and to measure the uncertainty of China's green GDP (GGDP) growth from a risk management perspective. With this in mind, we follow the idea of growth-at-risk (GaR) to propose the concept of green GaR (GGaR) and extend it to the mixed-frequency data environment. Specifically, we first measure China's annual GGDP using the System of Environmental Economic Accounting (SEEA), then construct China's monthly green financial index by a mixed-frequency dynamic factor model (MF-DFM), and finally monitor China's GGaR from 2008M1 to 2021M12 with the mixed data sampling-quantile regression (MIDAS-QR) method. The main findings are as follows: First, the proportion of China's GGDP to traditional GDP gradually increases from 81.97% in 2008 to 89.34% in 2021, which illustrates that the negative environmental externalities caused by China's economic growth are gradually decreasing. Second, the high-frequency GGaR has favorable predictive performance and is significantly superior to the common-frequency GGaR at most quantiles. Third, the high-frequency GGaR has good nowcasting performance, and its 90% and 95% confidence intervals include true value for all prediction horizons. Furthermore, it can provide early warning of economic downturns through probability density prediction. Overall, our main contribution lies in constructing a quantitative assessment and high-frequency monitoring of China's GGDP growth risk, which provides an effective tool for investors and companies to predict risk, and a reference for the Chinese government to better formulate sustainable development strategies.

Effect of Chinese Herbs on Serum Biochemical Parameters, Immunity Indices, Antioxidant Capacity and Metabolomics in Early Weaned Yak Calves.

Chinese traditional herbs are used widely as feed supplements to improve the immune response and antioxidant capacity of livestock. Twenty early-weaned 4-month-old yak calves (72.3 ± 3.65 kg) were divided randomly into four groups (n = 5 per group); three groups were provided with supplementary 80 mL/kg DMI of the root water extracts of either Angelica sinensis, Codonopsis pilosula or Glycyrrhiza uralensis, and one group (control) was not provided with a supplement. Compared to control calves, calves consuming the three herbal extracts increased serum concentrations of albumin (ALB) and glutathione peroxidase (GSH-Px), but decreased serum concentrations of free fatty acids (FFAs) and malondialdehyde (MDA) (p < 0.05). Calves consuming A. sinensis decreased (p < 0.05) serum concentration of total cholesterol (TC), and increased (p < 0.05) serum concentration of total proteins (TP). Serum FFA concentrations increased (p = 0.004) linearly with time in the control group, but not in the groups consuming herbs. Serum metabolomic data demonstrated that A. sinensis and C. pilosula regulate mainly amino acid metabolism, while G. uralensis regulates mainly carbon and amino acid metabolism. It was concluded that the three herbal root extracts, as dietary supplements, improved energy and nitrogen metabolism, and enhanced the antioxidant capacity of yak calves.

Effects of Management, Dietary Intake, and Genotype on Rumen Morphology, Fermentation, and Microbiota, and on Meat Quality in Yaks and Cattle.

Traditionally, yaks graze only natural grassland, even in harsh winters. Meat from grazing yaks is considered very healthy; however, feedlot fattening, which includes concentrate, has been introduced. We questioned whether this change in management and diet would have an impact on the rumen and meat quality of yaks. This study examined the morphology, fermentation, and microbiota of the rumen and the quality of meat of three groups of bovines: (1) grazing yaks (GYs, 4-year olds), without dietary supplements; (2) yaks (FYs, 2.5-year olds) feedlot-fattened for 5 months after grazing natural pasture; and (3) feedlot-fattened cattle (FC, Simmental, 2-year olds). This design allowed us to determine the role of diet (with and without concentrate) and genotype (yaks vs. cattle) on variables measured. Ruminal papillae surface area was greater in the FYs than in the GYs (P = 0.02), and ruminal microbial diversity was greater but richness was lesser in the GYs than in the FC and FYs. Concentrations of ruminal volatile fatty acids were greater in the yaks than in the cattle. In addition, both yak groups had higher protein and lower fat contents in meat than the FC. Meat of GY had a lower n6:n3 ratio than FY and FC, and was the only group with a ratio below r, which is recommended for healthy food. Essential amino acids (EAA), as a proportion of total AA and of non-essential AA of yak meat, met WHO criteria for healthy food; whereas FC did not.

Astragalus membranaceus Alters Rumen Bacteria to Enhance Fiber Digestion, Improves Antioxidant Capacity and Immunity Indices of Small Intestinal Mucosa, and Enhances Liver Metabolites for Energy Synthesis in Tibetan Sheep.

Natural, non-toxic feed additives can potentially replace chemical medications and antibiotics that are offered sheep to improve performance. In the present study, Tibetan sheep were supplemented with the root of Astragalus membranaceus (AMT), a traditional herb used widely in China. Twenty-four male Tibetan sheep (31 ± 1.4 kg; 9-month-old) were assigned randomly to one of four levels of supplementary AMT: 0 g/kg (A0), 20 g/kg (A20), 50 g/kg (A50) and 80 g/kg (A80) dry matter intake (DMI). The A50 and A80 groups increased the diversity of rumen bacteria on d 14 and the relative abundances of fiber decomposing bacteria. Supplementary AMT upregulated the metabolism of vitamins, nucleotides, amino acids and glycan, and downregulated the metabolism of lipids and carbohydrates. In addition, supplementary AMT enriched rumen bacteria for drug resistance, and reduced bacteria incurring cell motility. In general, AMT supplementation increased the concentrations of catalase (CAT), superoxide dismutase (SOD) total antioxidant capacity (T-AOC) and secretory immunoglobulin A (sIgA) in the small intestinal mucosa and CAT and SOD in meat tissue. The liver tissue metabolome response showed that AMT in the A80 lambs compared to the A0 lambs upregulated the metabolites for energy synthesis. It was concluded that supplementary A. membranaceus increased the relative abundances of fiber decomposing bacteria and improved the antioxidant capacities and immunity indices of small intestinal mucosa and meat tissue in Tibetan sheep.

Astragalus root extract improved average daily gain, immunity, antioxidant status and ruminal microbiota of early weaned yak calves.

BACKGROUND: Early weaning in yak calves is being attempted to improve yak reproduction rate. However, this has to be done with caution because of the high mortality rate of calves due to the lack of nutrients and the harsh environmental conditions. Twenty-four weaned male yak calves were used in a 60 day feeding trial in which astragalus root extract (ARE) was supplemented. They were assigned randomly to one of four dietary treatments (n = six per treatment) that differed in ARE level: 0 g kg-1 (control), ARE0 ; 20 g kg-1 , ARE20 ; 50 g kg-1 , ARE50; and 80 g kg-1 dry matter intake (DMI), ARE80 . RESULTS: Final bodyweight and average daily gain (ADG) were significantly higher and the DMI/ADG ratio was significantly lower in calves with ARE supplementation than control (ARE0 ) calves. Ruminal concentrations of acetate and propionate and serum concentration of superoxide dismutase in ARE80 calves were higher than in the other groups and serum concentration of insulin was higher in ARE80 calves than in ARE20 calves. Serum immunoglobulin G (IgG) and interleukin-2 (IL-2) concentrations in ARE-fed calves were higher than in controls. Serum tumor necrosis factor (TNF-α) concentration was higher in ARE50 and ARE80 groups than ARE0 calves and serum interleukin-6 (IL-6) concentration was higher in ARE80 than in ARE0 calves. Serum immunoglobulin A (IgA), IgG and immunoglobulin M (IgM) concentrations increased with age in ARE-fed calves. ARE supplementation increased the abundance of fiber degrading bacteria. CONCLUSION: ARE at a dosage of 5% to 8% DMI can be supplemented to early weaned yak calves to improve growth performance, antioxidant capacity and immunity. © 2020 Society of Chemical Industry.