Analyzing coral reef topography is critical for understanding both the formation mechanisms of coral reefs and coral spatial distribution patterns.However,most topographic studies have focused on small-scale or locali...Analyzing coral reef topography is critical for understanding both the formation mechanisms of coral reefs and coral spatial distribution patterns.However,most topographic studies have focused on small-scale or localized survey sites,and investigations of reef macro-topography patterns and their relationship with coral distribution are scant.To address this gap,we conducted a comprehensive investigation of macro-topographic patterns across 12 coral reefs covering 607 km2 in the Xisha Islands,South China Sea.Using digital elevation models constructed from satellite bathymetric data with 16 m resolution,we analyzed spatial variations of seven topographic indices at the reef,geomorphic zone,and reef slope orientation levels in shallow waters.Field surveys were integrated with topographic indices to interpret and model coral distribution patterns.Our results revealed significant topographic heterogeneity,particularly in reef slopes and lagoon patch reefs.Reef slopes ranged from 0°to 33°,with rugosity values between 1.00 and 1.19.The steepness of reef slopes varied by orientation,being steepest in the west,southwest,and south,while the consistency of slope gradients was highest in the south,east,and northeast.Furthermore,stress-tolerant coral cover on reef slopes was effectively predicted by the factors of topographic indices,water depth,and slope aspect.Additionally,the topographic changes in reef flats and shallow lagoons were minimal.These findings advance our understanding of coral reef formation mechanisms in the Indo-Pacific region and provide a theoretical foundation for the conservation and restoration of coral reef ecosystems.展开更多
Structural complexity is a critical factor in maintaining the key ecosystem services of coral reefs,such as fisheries,biodiversity,coastal protection,and ecotourism.However,the resilience of coral reefs to climate cha...Structural complexity is a critical factor in maintaining the key ecosystem services of coral reefs,such as fisheries,biodiversity,coastal protection,and ecotourism.However,the resilience of coral reefs to climate change and anthropogenic disturbances remains poorly understood owing to a lack of longterm data.This study used data from field surveys at Weizhou Island in the northern South China Sea,conducted from 2019 to 2024,to record the response trajectories of the coral community and structural complexity,and to estimate the key drivers in a relatively high-latitude coral reef.Following a bleaching event in 2020 and disturbance by two cyclones in 2023,live coral cover(LCC) initially declined but later recovered,suggesting a gain in thermal tolerance.Corals in the marine protected area(MPA) were less impacted than those in the non-protected area.However,the structural complexity decreased continuously,from 1.200 to 1.076,signifying simplification in coral morphological composition.Despite the decline in structural complexity,a significant positive correlation with fish density was observed in the MPA(R^(2)=0.91,p<0.05).Bayesian and generalized linear models identified thermal stress,cyclones,and anthropogenic activity as the primary drivers of the loss of structural complexity.These results,along with the divergent trajectories of LCC and structural complexity,highlight the limited resilience of a relatively high-latitude coral reef to climate change.The findings of this study demonstrate how an MPA can play a crucial role in enhancing ecosystem resilience by reducing local stressors and allowing marine life to recover,enabling the ecosystem to withstand a wider-reaching threat such as climate change.We recommend incorporating structural complexity into long-term monitoring and management networks for coral reef ecosystems facing climate change.展开更多
基金The Guangxi Science and Technology Program under contract No.AD25069075the National Natural Science Foundation of China under contract No.42276182+2 种基金the Major Talent Project of Guangxi Zhuang Autonomous Region under contract No.GXR-2BGQ2525027the Natural Science and Technology Innovation Development Doubling Program of Guangxi University under contract No.2023BZRC019the Guangxi Natural Science Foundation of China under contract No.2022GXNSFAA035548.
文摘Analyzing coral reef topography is critical for understanding both the formation mechanisms of coral reefs and coral spatial distribution patterns.However,most topographic studies have focused on small-scale or localized survey sites,and investigations of reef macro-topography patterns and their relationship with coral distribution are scant.To address this gap,we conducted a comprehensive investigation of macro-topographic patterns across 12 coral reefs covering 607 km2 in the Xisha Islands,South China Sea.Using digital elevation models constructed from satellite bathymetric data with 16 m resolution,we analyzed spatial variations of seven topographic indices at the reef,geomorphic zone,and reef slope orientation levels in shallow waters.Field surveys were integrated with topographic indices to interpret and model coral distribution patterns.Our results revealed significant topographic heterogeneity,particularly in reef slopes and lagoon patch reefs.Reef slopes ranged from 0°to 33°,with rugosity values between 1.00 and 1.19.The steepness of reef slopes varied by orientation,being steepest in the west,southwest,and south,while the consistency of slope gradients was highest in the south,east,and northeast.Furthermore,stress-tolerant coral cover on reef slopes was effectively predicted by the factors of topographic indices,water depth,and slope aspect.Additionally,the topographic changes in reef flats and shallow lagoons were minimal.These findings advance our understanding of coral reef formation mechanisms in the Indo-Pacific region and provide a theoretical foundation for the conservation and restoration of coral reef ecosystems.
基金supported by the National Natural Science Foundation of China(Grant No.42276182)the Major Talent Project of Guangxi Zhuang Autonomous Region(Grant No.GXR-2BGQ2525027)+1 种基金the Natural Science and Technology Innovation Development Doubling Program of Guangxi University(Grant No.2023BZRC019)the Guangxi Natural Science Foundation of China(Grant No.2022GXNSFAA035548)。
文摘Structural complexity is a critical factor in maintaining the key ecosystem services of coral reefs,such as fisheries,biodiversity,coastal protection,and ecotourism.However,the resilience of coral reefs to climate change and anthropogenic disturbances remains poorly understood owing to a lack of longterm data.This study used data from field surveys at Weizhou Island in the northern South China Sea,conducted from 2019 to 2024,to record the response trajectories of the coral community and structural complexity,and to estimate the key drivers in a relatively high-latitude coral reef.Following a bleaching event in 2020 and disturbance by two cyclones in 2023,live coral cover(LCC) initially declined but later recovered,suggesting a gain in thermal tolerance.Corals in the marine protected area(MPA) were less impacted than those in the non-protected area.However,the structural complexity decreased continuously,from 1.200 to 1.076,signifying simplification in coral morphological composition.Despite the decline in structural complexity,a significant positive correlation with fish density was observed in the MPA(R^(2)=0.91,p<0.05).Bayesian and generalized linear models identified thermal stress,cyclones,and anthropogenic activity as the primary drivers of the loss of structural complexity.These results,along with the divergent trajectories of LCC and structural complexity,highlight the limited resilience of a relatively high-latitude coral reef to climate change.The findings of this study demonstrate how an MPA can play a crucial role in enhancing ecosystem resilience by reducing local stressors and allowing marine life to recover,enabling the ecosystem to withstand a wider-reaching threat such as climate change.We recommend incorporating structural complexity into long-term monitoring and management networks for coral reef ecosystems facing climate change.
