Core Insights - The study published in the latest issue of "Science" highlights the critical role of the "global overturning circulation" in shaping the diversity and functionality of microbial communities in the South Pacific [1][2] - The research provides a new perspective on understanding the organizational patterns of marine ecosystems [1] Group 1: Research Findings - The research team collected over 300 full-depth water samples from the South Pacific, revealing the existence of a "prokaryotic phylogenetic leap layer" at approximately 300 meters below the surface, where microbial diversity sharply increases [1] - The study identified over 300 microbial genomes and tens of thousands of species, establishing a baseline for current marine microbial ecosystems [2] - Six microbial community groups and ten functional zones were formed, with three groups related to water depth and three corresponding to major water masses such as Antarctic bottom water and ancient Pacific deep water [1] Group 2: Implications - Microbial communities are central to the oceanic carbon cycle, influencing carbon sequestration, nutrient cycling, and solid carbon processes [2] - Changes in global overturning circulation due to climate change may alter microbial community distribution and functionality, potentially impacting the global carbon cycle in unknown ways [2]

Core Insights - The research team led by researcher Chen Jitao from the Nanjing Institute of Geology and Palaeontology has discovered that global warming, under current icehouse climate and high oxygen conditions, may lead to widespread ocean deoxygenation, similar to the Late Paleozoic Ice Age [1][2] Group 1: Research Findings - The Late Paleozoic Ice Age is noted as the longest icehouse climate period since the establishment of terrestrial higher plants and ecosystems, with atmospheric CO2 levels spanning from pre-industrial levels to future high carbon emission scenarios [2] - The exceptionally high oxygen environment during this period may be linked to the gigantism of marine and terrestrial animals and could have triggered the major marine biological radiation event from the mid-Carboniferous to the early Permian [2] - The research team studied carbonate rock sediment sequences from 310 to 290 million years ago in the Guizhou Luodian Basin, integrating carbon isotope data, atmospheric CO2 concentration, volcanic activity, and vegetation evolution to analyze global carbon cycling and ocean redox states [2] Group 2: Implications of Findings - The study found that increased organic carbon burial in the ocean during the research period likely led to a decrease in atmospheric CO2 concentration and an increase in oxygen concentration [2] - Intermittent massive carbon emissions could trigger repeated climate warming and seabed deoxygenation, potentially expanding the area of ocean deoxygenation to 4%-12%, which may lead to stagnation or decline in marine biodiversity [2]