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[Display omitted] • Significant differences in freeze–thaw processes between farmland and shelterbelt. • The migration and increment of soil water content in farmland were greater than in shelterbelt. • Land use patterns and initial soil water content had a greater impact on the occurrence of freeze–thaw processes than soil texture. • Soil texture was closely related to the amount of water migration during freeze–thaw. Seasonal freeze-thawing can affect the movement and distribution of soil moisture and thus impact the management of agroforestry. In this study, we analyzed the differences in the freeze-thawing of farmland and its shelterbelt by monitoring the dynamics of soil temperature (ST) and soil water content (All soil water content involved in this study is volumetric water content, SWC) at a depth of 0–100 cm in arid and semi-arid regions of northern China. The results showed significant differences in the freeze–thaw process between farmland and shelterbelt. Freeze-thawing in the upper soil layer (0–60 cm) of farmland and shelterbelt was significantly affected by air temperature (AT). Still, the shelterbelt was more resistant to freezing than farmland and maintained a higher soil temperature at all depths. The fluctuations of soil temperature and soil water content were also lower in shelterbelt than in farmland. In addition, farmland was frozen first but thawed later than the shelterbelt, with more freeze–thaw cycles. The migration and increment of soil water content were more significant in farmland than in shelterbelt at each soil depth during freeze–thaw. Land use patterns and initial soil water content had a greater impact on the timing of freeze–thaw onset than soil texture, but the latter was associated with soil water content migration. Our results improved the understanding of seasonal freeze–thaw processes and their effects on agroforestry. They can be used to develop appropriate management strategies for agriculture and forestry. [ABSTRACT FROM AUTHOR]

Room-temperature phosphorescence (RTP) materials have drawn widespread attention due to its unique property and extensive application, which makes finding effective ways to improve luminescence performance of RTP materials an urgent thing. We have prepared a series of polymers containing S/Se-naphthalimide derivatives that not only showed decent RTP properties in solid state, but also achieved RTP in aqueous solution. The heavy-atom effect of Se and hetero-atom effect of S can facilitate the spin-forbidden transfer of singlet-to-triplet excited states through intersystem crossing to populate triplet state thereby enhancing the RTP. The hydrogen-bonded crosslinking network of polymer systems endow the phosphorescence the good oxygen barrier property in both solid and aqueous states. This RTP-enhancing concept can lay a good foundation for the subsequent development of RTP materials with better performance. A series of polymers containing S/Se-naphthalimide derivatives have been prepared which processed decent room-temperature phosphorescent (RTP) performance. By enhancement of S/Se, the longest RTP lifetime of these materials up to 45.84 m s with orange afterglow, the highest total luminescence quantum yield is 30.9 % and their phosphorescence also can be detected in aqueous solution. [Display omitted] • Using Se/S as heavy atoms to adjust RTP behaviors in polymer system. • RTP of S/Se-containing polymer both in solid states and aqueous solutions. • Proper oxygen-resistance of aqueous RTP. [ABSTRACT FROM AUTHOR]