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Sulfur dioxide (SO2) is a major atmospheric pollutant and abiotic stressor. Although physiological studies on abiotic stressors have focused on fully expanded leaves, the resistance of leaf functional traits to SO2 during individual leaf development has not been studied. Thus, this study aimed to conduct SO2 static artificial fumigation experiments to evaluate changes in leaf functional traits and resistance to SO2 for three common landscape tree species (Syringa oblata Lindl. (S. oblata), Prunus cerasifera var. atropurpurea Jack. (P. cerasifera), and Ulmus pumila 'Jinye' (U. pumila)) in Changchun City and ontogeny under SO2 stress. Samples were collected on three days in autumn (1 September, 9 September, and 19 September 2019) for two different leaf stages (10 days and 40 days). In addition, remote sensing data were combined to explore the resistance mechanisms of broadleaf forests to different SO2 concentration classes during different seasons on a large scale. The results showed that the chlorophyll content, leaf temperature, green-peak reflectance, and Fv/Fm (maximal photochemical efficiency) at 10 days were significantly lower than that at 40 days, regardless of sampling date or SO2 concentration. Additionally, in general the SO2 resistance for 10 days leaves was consistently smaller than those for 40 days leaves in 3 tree species. On 9 September, 10 days leaves of the three tree species showed different leaf resistance performances under different SO2 concentrations in the order: P. cerasifera > S. oblata > U. pumila. Lastly, the extent of resistance decreased with increasing ρ(SO2) classes in different seasons, and the SO2 resistance was affected by season. We conclude that mature leaves are more resistant to SO2 stress than young leaves are. These results will provide scientific guidance on artificial plant community construction and prevention of future vegetation degradation. [ABSTRACT FROM AUTHOR]

Potato bears the burden of eliminating hunger and supporting food security. Quantitative assessment of potato drought disaster risk can help the sustainable development of the potato industry and improve the regional disaster management capacity. This is also a major and urgent demand for food security. This study constructed a comprehensive drought condition index (CDCI) for different months of the potato growing season based on the Soil-Plant-Atmosphere Continuum (SPAC) system, quantitatively assessed potato drought disaster risk based on the four-factor theory of natural disaster risk formation, and discussed the historical and future planting environmental conditions in Inner Mongolia, China. The results showed that the non-overlap between suitable areas of agro-climatic resources and main planting areas is the main reason for the occurrence of potato drought disasters, and the "Extremely high risk area" and "High risk area" areas were concentrated in the current main planting areas, which was one of the problems encountered in the sustainable development of potato industry in Inner Mongolia. The analysis of future drought hazard changes indicates the need to pay attention not only to the possible persistence of drought hazard in Near term, but also to the possible waterlogging hazard in Mid-Long term. The different situations of land use/cover change (LUCC) in Inner Mongolia and various agricultural resources and environmental zones (AgriREZones) have confirmed the necessity of separating regions for agricultural drought risk analysis and management. The present study can be used as a reference for adjusting the layout of the potato industry and provide a basis for agricultural disaster prevention and reduction. • A comprehensive drought condition index was constructed based on the "Soil-Plant-Atmosphere" continuum. • Agricultural resources and environment zoning is conducted to facilitate site-specific research. • In the coming period, in addition to drought there is also a need to pay attention to possible waterlogging. [ABSTRACT FROM AUTHOR]