Amazon water and carbon part ways as monsoon timing and rice resistance are recast
Amazon's water-carbon decoupling, two clocks governing the monsoon and a single-base deletion giving rice dual resistance reveal water pressure at three different scales.
Science··Midday
One stomatal pathway, diverging Amazon outcomes
Plants take in carbon and lose water through the same stomata, so carbon production and evapotranspiration are expected to move together. Forty years of satellite estimates show a weak or negative link across 64 per cent of the Amazon Basin. The separation is strongest during the dry season in forests that are not short of water. There, the correlation is -0.03 ± 0.14, while coupling has weakened since 1982, most clearly in intact forest, as atmospheric water demand has risen. The authors present drier air suppressing carbon uptake while raising demand for water as a hypothesis.[1]
Two clocks pace the monsoon
Four climate-simulation series for the summer monsoon covered the past 800,000 years in 4,000-year steps. Greenhouse-gas forcing had the strongest relationship with the long 100,000-year cycle, while precession aligned with the 20,000-year cycle. Insolation, greenhouse-gas and ice-sheet effects were switched on and off in turn to measure that separation. Sensitivity varied across the monsoon domain; this spatial variation offers a possible reconciliation of the different rhythms found in cave and loess records. The result belongs to a modelling study, and the local process captured by each proxy record still has to be assessed separately.[2]
One missing base gives rice two defences
A genome-wide screen in rice found a natural gene version called NLR8-Hap2 with a single-base deletion. The deletion shortens the protein and removes its leucine-rich repeat domain; the truncated protein binds more tightly to OsbHLH148, which governs drought tolerance, and OsBIHD1, which governs blast defence, stabilising both. Moving this version into elite indica and japonica cultivars increased resistance to both stresses without a detected yield penalty under normal field conditions. Tests under combined stress in other environments have yet to be reported.[3]
