Response of Vegetation Cover Change to Drought at Different Time-scales in the Beijing-Tianjin Sandstorm Source Region,China

Dominated by an arid and semiarid continental climate,the Beijing-Tianjin Sandstorm Source Region(BTSSR)is a typical ecologically fragile region with frequently occurring droughts.To provide information for regional vegetation protection and drought prevention,we assessed the relations between vegetation cover change(measured by the Normalized Difference Vegetation Index,NDVI)and the Standardized Precipitation Evapotranspiration Index(SPEI)at different time-scales,in different growth stages,in different subregions and for different vegetation types based on the Pearson's correlation coefficient in the BTSSR from 2000 to 2017.Results showed that 88.19%of the vegetated areas experienced increased NDVI in the growing season;48.3%of the vegetated areas experi-enced significantly increased NDVI(P<0.05)and were mainly in the south of the BTSSR.During the growing season,a wetter climate contributed to the increased vegetation cover from 2000 to 2017,and NDVI anomalies were closely related to SPEI.The maximum correlation coefficient in the growing season(Rmax)was significantly positive(P<0.05)in 97.84%of the total vegetated areas.In the vegetated areas with significantly positive Rmax,pixels with short time-scales(1-3 mon)accounted for the largest proportion(33.9%).The sensitivity of vegetation to the impact of drought rose first and then decreased in the growing season,with a peak in July.Compared with two subregions in the south,subregions in the north of the BTSSR were more sensitive to the impacts of drought variations,especially in the Xilingol Plateau and Wuzhumuqin Basin.All four major vegetation types were sensitive to the effects of drought variations,especially grasslands.The time-scales of the most impacting droughts varied with growth stages,regions,and vegetation types.These results can help us understand the relations between vegetation and droughts,which are important for ecological restoration and drought prevention.

Mechanism Exploration of the Classical Traditional Chinese Medicine Formula Huoluo Xiaoling Pill in Clinical Treatment and the Traditional Chinese Medicine Theory“Treating Different Diseases with the Same Method”:A Network Pharmacology Study and Molecula Docking Verification

Objective: To analyze the possible mechanism of the Huoluo Xiaoling Pill in the treatment of three diseases, hyperglycemia, hyperlipidemia, and metabolic syndrome, and to provide ideas for learning the mechanism of “Treating different diseases with the same method” in Traditional Chinese Medicine(TCM) theory. Materials and Methods: The Traditional Chinese Medicine System Pharmacology Database and Uni Prot databases were used to screen the main ingredients and targets of the Huoluo Xiaoling Pill. The Gene Cards database was used to screen the targets of the diseases, and Cytoscape 3.7.2 was used to construct a “Drug-Components-Targets-Disease” network to determine the core components. The STRING database was used to construct the protein-protein-interaction network, and gene ontology(GO) and Kyoto Encyclopedia of Genes and Genomics enrichment analyses were carried out on the Metascape database. Auto Dock 1.5.6 was used for molecular docking. Results: A total of 118 active components and 208 targets were screened in the Huoluo Xiaoling Pill. Quercetin, tanshinone IIA, luteolin, and ellagic acid were potential core components of Huoluo Xiaoling Pill treating the three diseases, and interleukin 6, Tumor necrosis factor, and vascular endothelial growth factor were potential key targets. Co-occurring GO biological processes involved responses to the molecules of bacterial origin, and the AGE-RAGE signaling, fluid shear stress, and atherosclerosis pathways were the co-occurring pathways. Molecular docking revealed good docking conditions between screened targets and components. Conclusion: This study predicted the mechanism of the Huoluo Xiaoling Pill in treating the three diseases. At the same time, the co-occurring targets and pathways between the three diseases provided a material basis for the TCM theory, “Treating different diseases with the same method.”