Clonal fragmentation drives performance deterioration of epiphytic and lithophytic ferns in a karst forest

Effects of clonal fragmentation on Pyrrosia nuda depend on growth stages in a rubber plantation

“…This result is consistent with previous findings. There were negative effects of clonal fragmentation on the survival rate and biomass of two clonal ferns Pyrrosia nummulariifolia and Lemmaphyllum microphyllum with different ecotypes of epiphytic and lithophytic clonal ramets ( Dai et al., 2023 ). This confirmed our initial research hypothesis in that the higher the fragmentation level, the more severe the negative influence.…”

“…As a biodiverse hotspot, the topography of Xishuangbanna features mountains and-valleys, with the Hengduan Mountains running north-south, covering approximately 95% of the region’s covered by mountains and hills. This region has a typical tropical monsoon climate and is characterized by a half-year dry season (November-April) and a half-year rainy season (May-October) ( Dai et al., 2023 ). According to the observation data from Xishuangbanna Station for Tropical Rainforest Ecosystem Studies (XSTRES), the monthly mean air temperature is approximately 22.5°C, and the mean annual precipitation is approximately 1500 mm (from 2005 to 2018), with more than 80% occurring during the rainy season.…”

“…The experiment involved ramets at three developmental stages/ages (1 st , 2 nd , and 3 rd ramet closest to the rhizome apex) with fiddlehead frond ramets, just-extended frond ramets, and mature frond ramets and included four levels of fragmentation as the treatment—single-, double-, triple- and intact-ramet treatments (see Figure 1 ). Based on previous experiments on clonal integration of epiphytic ferns, it is noted that water stress during the dry season may lead to the death of most single ramets; therefore, this study was focused on the influence of clonal fragmentation on the survival and performance in the rainy season with less water stress ( Lu et al., 2015 ; Zhang et al., 2019 ; Lu et al., 2020 ; Zhang et al., 2020b ; Dai et al., 2023 ).…”

“…Though one of the most natures of clonal plants is physiological integration, which means sharing resources and information within interconnected fragments of a clone ( Suzuki and Stuefer, 1999 ; Brezina et al, 2006 ). However, in previous studies, the whole clonal epiphytes decreased the growth and performance, while they relied on resource sharing within a clone and interspecific facilitation within canopy communities to mitigate severe stresses and negative effects ( Lu et al., 2016 , Lu et al., 2020 ; Dai et al., 2023 ). In particular, the growth and performance of two clonal plants, Pyrrosia nummulariifolia and Lemmaphyllum microphyllum , have been found to decline when they rely on clonal integration to deal with the negative effects of clonal fragmentation in a natural limestone forest ( Dai et al., 2023 ).…”

“…However, in previous studies, the whole clonal epiphytes decreased the growth and performance, while they relied on resource sharing within a clone and interspecific facilitation within canopy communities to mitigate severe stresses and negative effects ( Lu et al., 2016 , Lu et al., 2020 ; Dai et al., 2023 ). In particular, the growth and performance of two clonal plants, Pyrrosia nummulariifolia and Lemmaphyllum microphyllum , have been found to decline when they rely on clonal integration to deal with the negative effects of clonal fragmentation in a natural limestone forest ( Dai et al., 2023 ). However, our understanding of the impact of clonal fragmentation resulting from extreme weather and human activities on epiphytes in artificial forests and/or plantations remains limited.…”