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The article presents a study which focuses on the ecosystem evapotranspiration (ET) of tropical rain forest located in Xishuangbanna, China. The study conducted an eddy covariance flux measurement at the rain forest wherein a three-dimensional sonic anometer was used to measure the wind speed and virtual temperature of eddy covariance. The study reveals that soil water availability in hot-dry season can control the ET wherein it ET is also considered to be higher during dry season.

Leaf and fig phenology (including leafing, flowering, and fruiting) and syconium growth of Ficus racemosa were studied in Xishuangbanna, China. Leaffall and flushing of F. racemosa occurred twice yearly: in mid-dry season (December to March) and mid-rainy season (July to September). The adult leaf stage of the first leaf production was remarkably longer than that of the second. F. racemosa bears syconia throughout the year, producing 4.76 crops annually. Asynchronous fig production was observed at a population level. Fig production was independent of leafing. Fig production peaks were not evident, but fluctuation was clear. Diameter growth rates of syconium were normally higher in early developmental stages than in later stages, and reached a peak coinciding with the female flower phase. The mean ± SD of syconium diameter of the female flower phase was 2.19 ± 0.36 cm, and reached 3.67 ± 0.73 cm of the male flower phase. Syconium diameter and receptacle cavity quickly enlarged at the female and male flower phases. Monthly diameter increment of the syconium was primarily affected by average monthly temperature, rather than rainfall or relative humidity. [ABSTRACT FROM AUTHOR]

Riparian vegetation is an important inhabitant of numerous forest ecosystems, although it is vulnerable and affected by the changes in climate or microclimate. Due to the fluctuation in rainfall and surface water availability, riparian plants usually exposed to two different seasons throughout the year: a dry season and a rainy season. However, water use patterns among riparian plants are still poorly understood in the tropical monsoon region. In this study, we used stable isotope techniques (δD and δ18O) coupled with MixSIAR model to identify the water sources for riparian plants in a tropical forest of SW China. The results showed an apparent seasonal variation in water use patterns for most trees, and the spatial variations were less pronounced between the terrace and floodplain sites. Among most riparian trees, deep soil (below 50 cm) was the main water source in the dry season, and shallow soil (above 15 cm) was the primary water source during the rainy season. However, there was no change in water source for herbs and other shallow‐rooted species with the fluctuation in water availability. This result indicates that shallow‐rooted plants (i.e., herbs and seedlings) struggle for their survivability in a riparian ecosystem because of the water scarcity in shallow soil during the dry season. Thus, lower rainfall and/or extended dry period may affect the productivity and sustainability of riparian vegetation under a future climate change scenario. [ABSTRACT FROM AUTHOR]