Conclusion
Our 7-year field warming study demonstrated
that warming led to a net transfer of
soil P from moderately-available organic P and Fe-Pi to the plant
without altering litter P mineralization and ecosystem P loss. Warming
thus increases the plant biological “control” of the plant-soil
P-cycle, increasing the stocks of P involved in the fast P plant-soil
cycle and plant P-use efficiency (higher C:P ratio in litter). The
results suggest that warming changed net balance of plant-P cycle
through multiple processes (the enhanced plant P resorption, soil P
mineralization and dissolution) rather than in single form or process,
which extends our previous understanding of the climate-demand/supply
hypothesis and the application of nutrient resorption theory and
emphasizes the assessment of P dynamics at the ecosystem level. In this
humid tropical forest under warming, greater P supply to support higher
mass production is expected than previous prediction via short-term
experiments or studies with single evaluation, and moderate warming may
alleviate current P deficiency and/or limitation in tropical plants and
contribute to greater plant C fixation in a warmer future climate.