Water resource utilization characteristics and driving factors in the Hainan Island

The scarcity of water resources caused by the unique topography and uneven rainfall distribution in Hainan Island has become a major factor restricting local development. In order to provide effective and scientific reference basis for the overall water resource utilization status and solving this problem, this study calculated the water resource utilization situation of Hainan Island from 2017 to 2021 in detail using methods including water resource ecological footprint analysis. Furthermore, a spatial correlation analysis was conducted to examine the island's water resource utilization characteristics, and the driving factors behind the changes in water resource utilization over the past five years were analyzed using the LMDI model. The results show that:(1) During the study period, the water resource ecological footprint in Hainan Island exhibited a slow growth trend, while the ecological carrying capacity showed a downward tendency.The per capita ecological deficit of water resources remains relatively high, and the water consumption per 10 000 yuan GDP in the whole land continues to decrease, indicating that the overall pressure on water resource demand remains high with significant regional differences accompanied by the efficiency of water resource utilization steadily improving at the same time;(2) Agricultural water use accounts for the highest proportion in the entire water use structure, while ecological water use represents the smallest share, with a year-on-year increase, indicating that Hainan Island highlights the agricultural development and is increasingly conscious of the ecological environment;(3) Significant spatial differentiation in water resource utilization characteristics exists in Hainan Island, with the western region being a hot spot aggregation area for per capita water resource ecological footprint, per capita ecological carrying capacity of water resources, water consumption per 10 000 yuan GDP, while it is a cold spot cluster area for per capita ecological deficit of water resources. The opposite holds true for the eastern region of Hainan Island;(4) Economic and technological factors have a major impact on the changes in water resource ecological footprint within the designated area. Among them, economic factors drive the growth of the water resource ecological footprint in Hainan Island, and exacerbate local water resource consumption, while technological factors negatively contribute to the amount of water resource utilization in Hainan Island, indicating that advanced technology has improved water resource utilization efficiency and significantly reduced water resource consumption.

Lysimachia septemfida(Primulaceae),a new species from Yunnan,China

A new species, Lysimachia septemfida(Primulaceae), from Yunnan(Southwest China) is described and illustrated. The new species exhibits several unusual characters in Lysimachia including lack of a corolla,7-merous flowers, leaves in whorls of 3 and distinct multicellular nodiferous hairs, which make it readily distinguishable from all other species in this genus. The diagnostic differences between this new species and its suppositive allies are given. In addition, the systematic placement of this new species is also discussed based on an ITS molecular tree.

Identification of Dian Ji Xue Teng(Kadsura interior) with DNA barcodes

Objective: To identify Kadsura interior(Dian Ji Xue Teng, Schisandraceae) by using DNA barcoding.Methods: We analyzed five DNA barcodes(ITS, ITS2, psb A-trn H, mat K and rbc L) using DNA barcoding in terms of distance-based,tree-based and character-based identification to distinguish Kadsura interior and its adulterants.Results: In distance-based and tree-based identification, K. interior could be distinguished easily from the species of Schisandra and K. coccinea.In character-based identification, there are two single nucleotide polymorphisms(SNPs) in ITS and one SNP in psb A-trn H which can be used to distinguish K. interior from K. heteroclita and K. longipedunculata.Conclusion: The results indicate that DNA barcoding can be used to identify K. interior. ITS and psb A-trnH sequence can be the most ideal DNA barcode for discriminating K. interior and its adulterants by the combination analysis of distance-based, tree-based and character-based identification(SNPs).

Identification of Common Edible and Medicinal Mushrooms by DNA Barcoding

Objective:To identify common edible and medicinal mushrooms using the internal transcribed spacer(ITS) region.Method:A total of eighty-five samples belonging to forty-three species were used in this study.ITS regions were amplified and sequenced.All ITS regions were analyzed using BLAST and MEGA 5.10 methods.Results:Forty species were identified correctly via BLAST method whereas forty-one species were distinguished via Neighbor joining(NJ)tree.All the species could be distinguished by BLAST combined with NJ tree and ITS sequence characteristics.Conclusion:Forty-three common species of edible and medicinal mushrooms were effectively identified using DNA barcoding technology based on ITS region.