RESUMEN
Two tombs of the Southern Tang Dynasty (Qinling Tomb and Shunling Tomb), the most important cultural heritages in China, were built for emperors 1000 years ago and decorated with murals and stone sculptures. After their excavation in the 1950s, it was found that drastic fluctuations in the environment within the tombs had caused multiple diseases, such as salt efflorescence, powdering, and biodeterioration, which led to irreversible damage to the murals. This research comprised long-term (yearly) environmental monitoring and short-term (monthly) investigation into the distribution of salt crystallization and microbial growth within the two tombs. The objective was to unveil the relationship between the temporal and spatial distributions of the mural diseases and environmental characteristics while proposing a promising environmental regulation strategy for relic conservation. The results showed a gradual reduction in temperature fluctuation from the entrance to the back chamber and a distinct vertical stratification in relative humidity. The relative humidity in the upper areas of the tombs reached 100% during summer, while it averaged around 40-50% in the lower areas during winter. Consequently, significant condensation was observed on the ceiling in summer, whereas salt crystallization occurred on the murals in the lower space in winter. The distribution of these diseases was influenced by the airflow exchange between the interior and exterior. Furthermore, the structural disparities between the two tombs contributed to higher relative humidity and greater microorganism coverage in the Shunling Tomb compared to the Qinling Tomb. From the abovementioned findings, we suggest that microclimate control is essential for mitigating mural deterioration and should be paid more attention in the future.
RESUMEN
Metal-resistant endophytic fungi from roots improved phytoremediation efficacy of host plants; however, the effects of endophytic fungi from plant aerial parts on host plants are unknown. The aim of this study was to develop a feasible method to screen fungal endophytes from stems and roots of Brassica napus and to investigate effects of the endophytic fungi on growth and phytoremediation efficiency of the plant. Endophytic Fusarium sp. CBRF44, Penicillium sp. CBRF65, and Alternaria sp. CBSF68 with different traits were isolated from roots and stems of rapes grown in a metal-contaminated soil. Fusarium sp. CBRF44 (resistant to 5 mM Cd and 15 mM Pb, isolated from roots) and Alternaria sp. CBSF68 (resistant to 1 mM Cd and 10 mM Pb, isolated from stems) could produce indole-3-acetic acid (IAA) and siderophore; Penicillium sp. CBRF65 (tolerate 2 mM Cd and 20 mM Pb, isolated from roots) could not produce IAA and siderophore but showed the highest phosphate-solubilizing activities. Fusarium sp. CBRF44 and Penicillium sp. CBRF65 significantly increased the rape biomass and promoted the extraction efficacy of Pb and Cd, while Alternaria sp. CBSF68 did not show similar results. Penicillium sp. CBRF65 and Fusarium sp. CBRF44 could be frequently recovered from inoculated rape roots, while Alternaria sp. CBSF68 was scarcely recovered. The results indicate that the colonizing capacity of endophytic fungi in roots is important to improve phytoremediation efficacy of host plants.
