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In this paper, a stable porous biomass carbon (BC) and gold (Au) nanoparticles modified carbon ionic liquid electrode (CILE) was prepared for the investigation of direct electrochemistry and electrocatalysis of myoglobin (Mb). BC was synthesized via pyrolysis of Hainan's natural tropical plant Lagerstroemia indica leaves, which was modified on the surface of CILE with Au nanoparticles further electrodeposited on the electrode surface. Then, Mb was cast on the nanocomposite‐modified electrode to obtain an electrochemical sensing platform with Nafion film (Nafion/Mb/Au−BC/CILE). Direct electrochemistry of Mb on the modified electrode was investigated with appearance of a pair of enhanced redox peaks, indicating direct electron transfer rate of Mb was accelerated due to the presence of Au−BC nanocomposite. Au−BC nanocomposite exhibited high conductivity, good biocompatibility, and large surface area, which was beneficial for electron transfer of Mb. The Mb modified electrode showed excellent electrocatalytic activity toward the reduction of trichloroacetic acid (TCA) and sodium nitrite (NaNO2), which was further used to establish a new electroanalytical method with satisfied sensitivity in real samples analysis. [ABSTRACT FROM AUTHOR]

Natural pollen traps have been known for many years. This study analyzed the palynological characteristics of 12 ant nests on branches and 12 surface soil samples, collected from tropical areas of Yunnan and Hainan in China. Pollen grains and spores of 21 taxa belonging to 21 families were recorded from Xishuangbanna Tropical Botanical Garden and 30 taxa from 27 families were recorded from Xinglong Tropical Botanical Garden. Ant nests yielded nine taxa belonging to nine families from the Geopark in Haikou. There is a close relationship between the pollen assemblages from ant nests and those from surface soil. Although the average similarity of pollen taxa between them reaches approximately 70%, surface soil proves to be a more effective trap than ants' nests. [ABSTRACT FROM AUTHOR]

With decreasing population sizes and fragmentation of the original habitats of pteridophytes in Hainan Island, the abundance of most pteridophytes has been dramatically reduced, and some species may be at the brink of extinction. To assess the natural distribution of pteridophytes on Hainan Island, we conducted three analyses: flora, niche, and habitat. Thirty-two species of endangered pteridophytes in 21 families were found in Hainan Island, accounting for 8% of the 400 pteridophytes species there. Floristic studies showed that 9% of these 32 species are tropical, 50% are tropical Asian, 20% are pan-tropical, 3% are from East Asia, 3% from the Southern Hemisphere, and 15% are endemic to Hainan Island. Niche analysis showed that 21 of the 32 species (66%) are epiphytic or semi-epiphytic, while 11 (34%) are terrestrial. About 24 species of endangered pteridophytes are distributed in protected, conservation regions and the others are distributed partly in the conservation and non-conservation regions. In species-poor families (< 6 species), most of the species are endangered. [ABSTRACT FROM AUTHOR]