RESPON FOTOSINTESIS MAKROALGA TERHADAP TEKANAN DESIKASI PADA ZONA INTERTIDAL BERBATU DI DENSHIN HAMA PERAIRAN MURORAN, JEPANG

Dessiccation factors is affecting to photosynthesis response in macroalgae leaf exposed to light of the environment. Hypothesis of this research is macroalgae species scattered in upper zone having high tolerance against dessiccation. This research aims to analyzing macroalgae spesies productivity with using PAM fluorometer. Some species of seaweed was collected like Ulva pertusa, Polyopes affinis, Gloiopeltis furcata, Sargassum thunbergiii and Saccharina japonica. Seawed sampling is based on it dominance in the rocky intertidal zone which includes upper, middle and lower zone. Result of the study show Ulva pertusa less tolerance to dessiccation stress and rarely it can growth in rocky intertidal zone. Nevertheless, species of Polyopes affinis, Gloipertis furcata, Sargassum thunbergii and Saccharina japonica have been gradually increased which it show ability to dessiccation stress from exposure to free air

Life histories determine divergent population trends for fishes under climate warming

Most marine fish species express life-history changes across temperature gradients, such as faster growth, earlier maturation, and higher mortality at higher temperature. However, such climate-driven effects on life histories and population dynamics remain unassessed for most fishes. For 332 Indo-Pacific fishes, we show positive effects of temperature on body growth (but with decreasing asymptotic length), reproductive rates (including earlier age-at-maturation), and natural mortality for all species, with the effect strength varying among habitat-related species groups. Reef and demersal fishes are more sensitive to temperature changes than pelagic and bathydemersal fishes. Using a life table, we show that the combined changes of life histories upon increasing temperature tend to facilitate population growth for slow life-history populations, but reduce it for fast life-history ones. Within our data, lower proportions (25–30%) of slow life-history fishes but greater proportions of fast life-history fishes (42–60%) show declined population growth rates under 1 °C warming. Together, these findings suggest prioritizing sustainable management for fast life-history species