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Paclobutrazol (PAC), as a commonly used plant regulator, has the important function of improving the plant’s stress resistance. Sequoia sempervirens Endl. is a large caliber, fast-growing timber species and one of the world’s five major landscaping tree species. This study researched the effects of spraying PAC on the growth and photosynthetic activity of S. sempervirens seedlings. The results showed the plant height and the plant crown diameter were decreased significantly with the increase in PAC concentration (500 – 3,000 mg·dm−3). However, the ground shoot diameter, net photosynthetic rate, stomatal conductance, inter-cellular CO2 concentration, transpiration rate, actual photochemical quantum yield, and photosynthetic electron transport rate all showed the trend of increasing first reaching the maximum at 2,000 mg·dm−3 and then decreased. Water use efficiency showed the opposite trend. Spraying 2 times was better than once. The conclusion suggests that PAC can protect the photosynthetic activity and improve the resistance of S. sempervirens seedlings under natural cooling and draught in autumn and winter.

In order to explore the reasons that affect the flow of material and energy in the river, the Longji terraces are used as the research area, and the methods of field investigation and geospatial information technology are used to carry out research. The results show that human activities, vegetation coverage and the establishment of reservoirs are all factors that affect the flow of material and energy in the river.

Longji Terrace, one of the three ancient terraces in China, is a comprehensive tourist scenic spot with agricultural terraces as the main body and integrating natural landscape, cultural landscape and ethnic customs. In this paper, taking Longji Terrace in Guilin as the research object, using geographic information technology to study its ecosystem structure from the aspects of space, components, etc., to explore the material and energy flow patterns of the ecosystem, and to analyze the service functions of the ecosystem, so as to provide basic information for the healthy and sustainable development of the local ecological environment.

Highlights: [•] Large-diameter tube-like mesoporous TiO2 was synthesized using CTAB and urea. [•] A possible mechanism for the formation of tube-like mesoporous TiO2 was proposed. [•] Tube-like TiO2 was suitable for photodegradation of papermaking wastewater. [•] Tube-like TiO2 showed much higher photocatalytic activities than Degussa P25. [ABSTRACT FROM AUTHOR]