Phenology-related water-use efficiency and its responses to site heterogeneity in rubber plantations in Southwest China

Dry season temperature and rainy season precipitation significantly affect the spatio-temporal pattern of rubber plantation phenology in Yunnan province

“…RRIM 600 and GT 1 defoliated and refoliated one to two weeks earlier than clones Yunyan 277-5, Yunyan 34-4, and PR 107, and these two clones also have shorter wintering periods compared to the other three clones ( Liyanage et al., 2019 ). Planting density and stand age are impact phenology, with rubber mix spacing ranging from 4 to 12 m ( Lin et al., 2022 ). Disease outbreaks, like springtime powdery mildew, can lead to substantial leaf shedding and a delay in SOS ( Guyot et al., 2001 ; Kou et al., 2015 ; Zhai et al., 2019 ; Zhai et al., 2023 ).…”

“…The prevalent mean annual temperature falls between 19.4 and 27.6°C, whereas annual precipitation oscillates between 1200 to 1900 millimeters ( Zhai et al., 2019 ; Zhai et al., 2023 ). The regional climate demonstrates distinct seasonality, encompassing a rainy season (May to October), cool-dry season (November to February), hot-dry season (March to April) each year ( Lin et al., 2018 ; Lin et al., 2022 ; Zhai and Xu, 2022 ). The SOS and the EOS of rubber plantations occur during the dry season (November to April), a period typically marked by diminished precipitation and lower temperatures ( Cao et al., 2006 ; Liu et al., 2007 ; Yu et al., 2014 ; Lin et al., 2018 ).…”

“…A selection of thirty-two representative sample points was made at random, informed by high-resolution satellite imagery from Google Earth. Considerations were given to essential characteristics, such as the stand age (> 4) and altitude of rubber plantations ( Lin et al., 2022 ), ensuring an accurate representation of the plantation landscape. To validate the satellite-derived phenological indicators, we employed field-based data on SOS (refoliation, where leaves transition from copper-brown to light green) and EOS (defoliation, where leaves shift from light yellow to almost completely yellow).…”

“…Consequently, our understanding of how tropical vegetation responds to global climate change remains considerably constrained ( Abernethy et al., 2018 ; Qian et al., 2021 ). The extensive distribution and distinct phenological stages make rubber tree ideal subjects for studying phenology in tropical regions ( Guyot et al., 2001 ; Lin et al., 2022 ). Acquiring accurate phenology data through remote sensing enhances management’s ability to forecast production activities, providing valuable insights into the response of tropical vegetation to climate change.…”

“…While there is a rubber of phenological research concerning the Xishuangbanna region, there is a conspicuous dearth of studies exploring the inter-annual variation trends of rubber tree phenology within Yunnan ( Liu W. et al., 2013 ; Tan et al., 2014 ; Xiao et al., 2021 ; Chen G. et al., 2023 ). Furthermore, the potential influence of global climate change on rubber tree phenology remains unclear ( Liyanage et al., 2019 ; Zhai et al., 2019 ; Lin et al., 2022 ). Therefore, acquiring refined phenological data is imperative to devise comprehensive management strategies for Yunnan’s rubber plantations, as well as predicting potential impacts of climate change on rubber tree phenology.…”