Effects of typhoon disturbances on seasonal and interannual patterns of litterfall on coniferous and broadleaf plantations in Xitou, central Taiwan

Abstract

Many environmental and climatic disturbances can significantly change the magnitude and pattern of litterfall. This study investigated the effects of typhoon disturbances on the seasonal and interannual patterns of litterfall on coniferous and broadleaf plantation stands in Xitou, central Taiwan. Throughout the study period from 2012 to 2018, typhoon disturbances were recorded in 4 of these 7 years, whereas only minor or even no typhoon disturbances occurred in the other 3 years. Our results demonstrated that the pattern of monthly litterfall varied substantially between the coniferous and broadleaf stands. The coniferous stands exhibited a substantial litterfall pulse due to typhoon disturbances. By contrast, typhoon disturbances exerted a minor impact on the broadleaf stands. The litterfall seasonality of the coniferous stands was higher than that of the broadleaf stands, especially in the years with typhoon disturbances. Furthermore, the yearly variation caused by typhoon disturbances was distinct at the coniferous stands; the annual litterfall mass at the coniferous stands in the years with typhoon disturbances was more than twice as high as that in the years without typhoon disturbances, namely 6,000 kg ha −1 yr −1 versus 2,500 kg ha −1 yr −1 . By contrast, the annual litterfall mass at the broadleaf stands did not differ significantly among the study years. Because of high interannual variation, long-term sampling is essential for accurate estimation of annual litterfall at coniferous stands. For broadleaf plantations, interannual litterfall variation seems less critical, and spatial variability should be considered because of higher variability in terms of site conditions.

Using homemade stainless steel dendrometer band for long term tree growth measurements

“…The consistency of the band and tape observations indicate that the homemade stainless steel dendrometer bands are suitable for monitoring the long-term diameter increments of trees. The dendrometer bands used in this study are resistant to high humidity, high temperatures, and mechanical disturbances due to typhoons and heavy rain (Cheng et al 2020 ). The results also suggest that the dendrometer bands performed well on both coniferous and broadleaf trees.…”

“…In this study, we painted measurement location on the trunks to minimize the errors from remeasurements. However, high precipitation in Xitou might fade the paint rapidly and grant the mark of some trees unmarkable in the following measurements (Cheng et al 2020 ). Other errors, such as neglecting to account for the tension of the tape on trees or to level the tape at the proper plane, may have potentially affected the quality of the results and have caused the systematic differences (Williams et al 1999).…”

“…The mean annual temperature over the last 30 years in Xitou was 16.6°C, and the mean annual precipitation was 2635 mm. Typhoons and heavy rainstorm events are common natural disturbances in summer and fall in the area (Cheng et al 2020 ).…”

“…The two youngest BR stands were Cerasus campanulate and Acer serrulatum at BR1 and Liquidambar formosana at BR2. The mean diameter at breast height (DBH) of the stands ranged from 12.6 cm at BR2 to 48.0 cm at CP1 and increased with stand age (Table 1 ) (Cheng et al 2020 ).…”