Publications by authors named "Han-mao Li"
To investigate the impact of elevated ozone (O3) on CO2 emission from soil-winter wheat system, outdoor experiments with simulating elevated O3 concentration were conducted, and static dark chamber-gas chromatograph method was used to measure CO2 emission fluxes. Results indicated that the elevated O3 did not change the seasonal pattern of CO2 emissions from soil-winter wheat system, but significantly decreased CO2 emission fluxes during turning-green stage and elongation-pregnant stage. From heading to maturity, CO2 emission fluxes were not found to be significant difference under 100 nL x L(-1) O3 treatment compared with the control, while 150 nL x L(-1) O3 treatment significantly declined CO2 emission fluxes.
View Article and Find Full Text PDFTo investigate the effects of elevated nitrogen deposition on forest soil respiration, a simulated nitrogen deposition field experiment was conducted in northern subtropical deciduous broad-leave forest from April 2008 to April 2009. Nitrogen treatments included the control (no N addition, CK), low-N [50 kg x (hm2 x a)(-1), T(L)], medium-N [100 kg x (hm2 x a)(-1), T(M)], and high-N [150 kg x (hm2 x a)(-1), T(H)]. The respiration rates were measured by a static chamber-gas chromatograph method.
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- A field experiment in 2008 studied how enhanced UV-B radiation and straw application affect soil respiration in soybean fields using an automated CO2 flux system to measure results.
- Findings showed that enhanced UV-B radiation decreased soil respiration by 30.31%, while straw application increased it by 14.51%, and the combination of both treatments had no significant impact.
- The study also identified a positive relationship between soil respiration rates and soil temperature across the different treatments, with notable temperature sensitivity coefficients (Q10) indicating that UV-B radiation and straw application influenced soil respiration dynamics.
Article Synopsis
- A study was conducted to examine how increased UV-B radiation affects chlorophyll fluorescence in soybeans using a pulse amplitude modulation fluorometer during various growth stages.
- Results indicated that enhanced UV-B decreased chlorophyll content significantly across all growth stages, with the highest reduction during pod-setting, and led to a lowered maximum potential relative electron transport rate and effective quantum yield in specific light conditions.
- The findings highlight that increased UV-B not only reduces critical photosynthesis components but also harms electron transport and protective mechanisms, ultimately lowering the photosynthetic efficiency of soybeans.
Field experiment was carried out in the spring of 2008 in order to investigate the effects of increased UV-B radiation on the temperature sensitivity of wheat plant respiration and soil respiration from elongation to flowering periods. Static chamber-gas chromatography method was used to measure ecosystem respiration and soil respiration under 20% UV-B radiation increase and control. Environmental factors such as temperature and moisture were also measured.
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