Mangrove Species Exhibit Contrasting Photosynthetic and Water-Use Strategies in Bali, Indonesia

Coastal forest ecosystems, particularly mangroves are directly exposed to the impacts of climate change, including sea-level rise, extreme weather events, and altered precipitation patterns, while simultaneously being recognized as key nature-based solutions capable of delivering both climate adaptation and mitigation benefits. Mangroves play avital role in climate resilience, offering both carbon sequestration and coastal protection under increasing climate pressures.

In this study, we investigates species-specific physiological responses among dominant of mangrove and semi-mangrove species in Bali, Indonesia. Net photosynthetic rate (A) was measured using portable gas exchange systems (LI-6400 and LI-6800), and instantaneous WUE and intrinsic WUE (iWUE) were calculated. In addition, A–Ci response curves were analyzed and fitted using the Farquhar–von Caemmerer–Berry model to estimate the maximum carboxylation rate (V_cmax) and maximum electron transport rate (J_max).

Significant interspecific differences were observed in both photosynthetic performance and water-use characteristics (p < 0.001). Sonneratia alba exhibited the highest net photosynthetic rate (15.29 ± 2.39 μmol CO₂ m⁻² s⁻¹), whereas Pongamia pinnata and Hibiscus tiliaceus showed high iWUE values (96.51 ± 44.37 and 87.62 ± 20.73 μmol CO₂ mol⁻¹ H₂O, respectively), indicating more water-conservative strategies.

Furthermore, A–Ci curve fitting revealed significant species-specific differences in V_cmax and J_max (p = 0.003 and 0.016, respectively), highlighting functional differentiation along coastal environmental gradients. By integrating in situ gas exchange measurements and A–Ci curve analysis, this study demonstrates interspecific variation in carbon acquisition and water-use strategies among mangrove and semi-mangrove species in Bali. Provides foundational data for our findings provide and physiological evidence to support effective mangrove selection in Nature-based solution(Nbs).