Hadal ocean sediments, found at sites deeper than 6,000 m water depth, are thought to contain microbial communities distinct from those at shallower depths due to high hydrostatic pressures and higher abundances of organic matter. These communities may also differ from one other as a result of geographical isolation. Here we compare microbial community composition in surficial sediments of two hadal environments—the Mariana and Kermadec trenches—to evaluate microbial biogeography at hadal depths. Sediment microbial consortia were distinct between trenches, with higher relative sequence abundances of taxa previously correlated with organic matter degradation present in the Kermadec Trench. In contrast, the Mariana Trench, and deeper sediments in both trenches, were enriched in taxa predicted to break down recalcitrant material and contained other uncharacterized lineages. At the 97% similarity level, sequence-abundant taxa were not trench-specific and were related to those found in other hadal and abyssal habitats, indicating potential connectivity between geographically isolated sediments. Despite the diversity of microorganisms identified using culture-independent techniques, most isolates obtained under in situ pressures were related to previously identified piezophiles. Members related to these same taxa also became dominant community members when native sediments were incubated under static, long-term, unamended high-pressure conditions. Our results support the hypothesis that there is connectivity between sediment microbial populations inhabiting the Mariana and Kermadec trenches while showing that both whole communities and specific microbial lineages vary between trench of collection and sediment horizon depth. This in situ biodiversity is largely missed when incubating samples within pressure vessels and highlights the need for revised protocols for high-pressure incubations.

It is almost a truism that contemporary sport is embedded in the global political economy, as well as in the development of the modern international state system. Sport is conceptualized as practices, institutions, and ideologies that have evolved and migrated across national boundaries under globalization's Modernizing China in the Olympic spotlight

Thousands of kilometers of shelterbelt plantations of Casuarina equisetifolia have been planted to protect the southeast coastline of China. These plantations also play an important role in the regional carbon (C) cycling. In this study, we examined plant biomass increment and C accumulation in four different aged C. equisetifolia plantations in sandy beaches in South China. The C accumulated in the C. equisetifolia plant biomass increased markedly with stand age. The annual rate of C accumulation in the C. equisetifolia plant biomass during 0–3, 3–6, 6–13 and 13–18 years stage was 2.9, 8.2, 4.2 and 1.0 Mg C ha−1 yr−1, respectively. Soil organic C (SOC) at the top 1 m soil layer in these plantations was 17.74, 5.14, 6.93, and 11.87 Mg C ha−1, respectively, with SOC density decreasing with increasing soil depth. Total C storage in the plantation ecosystem averaged 26.57, 38.50, 69.78, and 79.79 Mg C ha−1 in the 3, 6, 13 and 18- yrs plantation, with most of the C accumulated in the aboveground biomass rather than in the belowground root biomass and soil organic C. Though our results suggest that C. equisetifolia plantations have the characteristics of fast growth, high biomass accumulation, and the potential of high C sequestration despite planting in poor soil conditions, the interactive effects of soil condition, natural disturbance, and human policies on the ecosystem health of the plantation need to be further studied to fully realize the ecological and social benefits of the C equisetifolia shelterbelt forests in South China.

Global warming is increasingly challenging for wetland ecological function. A 22 temperature controlled microcosm system was developed to simulate climate change 23 scenarios of an ambient temperature (control) and an elevated temperature (+5 ℃). 24The effects and associated mechanisms of warming on phosphorus (P) fluxes at the 25 sediment-water interface of six subtropical wetlands were investigated. The results 26 indicated that P fluxes were generally enhanced under the experimental warming as 27 measured by higher P concentrations in the porewater and overlying water as well as 28 higher benthic P fluxes. The release of P from sediment to porewater occurred more 29 strongly and quickly in response to experimental warming compared to the 30 subsequent upward transfer into overlying water. The average accumulative benthic P 31 output from the tested wetlands under the experimental warming was greater by 12.9 32 g cm -2 y -1 (28%) for total P and 8.26 g cm -2 y -1 (25%) for dissolved reactive P, 33 compared to the ambient scenarios. Under warming the redistribution of P fractions in 34 sediments occurred with greater NH 4 Cl-P and lower BD-P (extracted by a bicarbonate 35 buffered dithionite solution) accompanied by greater NaOH-P. The higher temperature 36 enhanced total phospholipid fatty acids. A shift in the microbial community was also 37 observed with a relative dominance of fungi (a 4.7% increase) and a relative decline 38 (by 18%) in bacterial abundance, leading to the higher secretion of phosphatase. 39Comparing between wetlands, the potential P fluxes in the nutrient-enriched wetlands 40 were less impacted by warming than the other wetland types investigated. Thus 41 wetlands characterized by low or medium concentrations of P in sediments were more 42 susceptible to warming compared to P-rich wetlands. 43