Preliminary study on the heat preservation function of Androsace tapete Maxim. on the Qinghai-Tibet Plateau

To explore the dominant factors determining thermal insulation in Androsace tapete Maxim., as well as its adaptability to survive extreme temperature changes, the internal temperatures of living and dead individuals were measured. The diurnal changes in surface and internal temperatures of A. tapete and nearby air and soil temperatures were also recorded in summer, winter, and under simulated hail conditions. The temperature data revealed no significant differences between the internal temperatures of living and dead individuals of A. tapete. For diurnal temperature changes, the variation amplitude of the surface temperature of A. tapete was much larger than that of the air, while the variation amplitude of the internal temperature was similar to that of the soil, which was much lower than that of the air. Although the surface temperature dropped to 0℃ after the low-temperature simulated hail treatment, the internal temperature was maintained above 10℃. These results showed that the heat preservation effect of A. tapete was mainly due to its structural characteristics and was less affected by altitude differences, metabolic activities, and cold acclimation. Its heat preservation capacity was slightly weaker than the 5-cm soil layer, which may significantly buffer the high plateau from severe diurnal temperature differences and reduce the stress of extreme environmental temperatures. This study compared diurnal variation in the internal temperature of A. tapete in summer and winter, as well as the internal temperature of surviving and dead individuals, which should inform research on the structural characteristics of cushion plants adapted to extreme environments.