In Xishuangbanna (Southwest China), banana plants are widely cultivated on hillslopes, and soil erosion frequently occurs during the rainy season. However, our knowledge regarding the factors affecting soil erosion in banana plantations in this area is very limited. No information is available to estimate the splash erosive power of throughfall (TF) in banana plantation and the role of banana leaf traits in splash erosion.
In a study published in CATENA, researchers from Xishuangbanna Tropical Botanical Garden (XTBG) investigated the characteristics of throughfall (TF) and throughfall kinetic energy (TKE) and the effect of leaf shape on TKE at canopy drip points under the individual banana plant (IBP) and the whole banana plantation (WBP) canopies.
They found that the TF volume accounted for 80.2% and 84.7% of the incident rainfall under the IBP and WBP canopies, respectively. Banana canopy potentially induced high variability in the TF distribution at the both canopy scales.
The kinetic energy of raindrops significantly varied among canopy drip points (D), canopy non-drip points (ND) and the open field (CK). The KE at canopy drip points was significantly higher than that at canopy non-drip points and in open fields under both the IBP and the WBP canopies, implying that the negative effect of banana canopy drip points was far greater than the protective effect of non-drip points on splash erosion.
Moreover, the TKE exhibited different patterns among the five leaf shapes, valley (Va), overlap (Ov), tip (Ti), breakage (Br) and complex shapes (Cs). In particular, the highest TKE appeared under Cs, the lowest under Ti, and TKE did not significantly differ among Va, Ov and Br.
“These results suggest that the influence of the distinctive banana leaf shapes on TKE was notable. These findings will provide an essential reference for future studies concerning the mechanism of soil erosion under banana plantations and other agroecosystems,” said LIU Wenjie, principal investigator of the study.
LIU Wenjie Ph.D Principal Investigator
Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, China