Influences of anthropogenic acids on carbonate weathering and CO2 sink in an agricultural karst wetland (South China)

Carbonate minerals are the largest carbon (C) reservoir on earth. Quantitative assessment of carbonate weathering and CO2 sink flux caused by anthropogenic acids in karst wetland regions is imperative to improve understanding of the hydrogeochemical evolution and global C cycle in karst ecosystem. In this study, a typical field observation was conducted in the Huixian karst wetland (HKW) in South China. The hydrogeochemical and isotopic (δ15N-NO3–, δ18O-NO3–, and δ13CDIC) analyses combined with the MixSIAR model and stoichiometric coefficients were used to quantitatively estimate the influence of H2CO3, HNO3 and H2SO4 on carbonate weathering and CO2 sink flux. The results obtained showed that anthropogenic HNO3 and H2SO4 affect carbonate weathering in the HKW, evidenced by the significant correlations between hydrogeochemical parameters and δ13CDIC value. The quantitative results showed high contributions of HNO3 and H2SO4 to carbonate weathering in karst groundwater, with contribution ratio values of 20.91 ± 19.29 and 21.69 ± 26.88%, respectively. Besides karst water over-exploitation, this finding suggested that these anthropogenic acids were also an important cause of a decrease in ecological water levels, resulting in the shortage of karst water resource and degradation of wetland ecosystem. Moreover, the involvement of anthropogenic acids in the natural chemical weathering has significantly decreased the CO2 sink flux by 11.23 ± 7.94 and 41.60 ± 30.24% for surface water and groundwater, respectively, thereby potentially affecting the karst C cycle and global climate change. This present study provided an integrated quantitative approach for estimating the influence of H2CO3, HNO3, and H2SO4 on carbonate weathering and CO2 sink in karst wetland regions. Our study highlighted that the effects of anthropogenic acids on carbonate weathering need to be considered in future studies on the restoration of wetland ecosystems, particularly in intensive agricultural study areas

Effectiveness of acupuncture for breast cancer related lymphedema: protocol for a single-blind, sham-controlled, randomized, multicenter trial

Abstract Background Although various treatments for breast cancer related lymphedema exist, there is still a need for a more effective and convenient approach. Pilot studies and our clinical observations suggested that acupuncture may be a potential option. This study aims to verify the effectiveness of acupuncture on BCRL and evaluate its safety using a rigorously designed trial. Methods/Design Women who are clinically diagnosed as unilateral BCRL, with a 10% to 40% increase in volume compared to the unaffected arm, will be recruited. Following baseline assessment, participants will be randomized to either the real acupuncture group or sham-acupuncture group at a ratio of 1:1, and given a standard real acupuncture or sham-acupuncture treatment accordingly on both arms followed by the same usual care of decongestive therapy. Volume measurements of both arms will be performed for every participant after each treatment. Data collected at baseline and the last session will be used to calculate the primary outcome and secondary outcomes. Other data will be exploited for interim analyses and trial monitoring. The primary outcome is the absolute reduced limb volume ratio. Secondary outcomes are incidence of adverse events and change in quality of life. A t test or non-parameter test will be used to compare the difference between two groups, and assess the overall effectiveness of acupuncture using the SPSS software (version 12). Discussion This study will help expand our knowledge about the effectiveness of acupuncture on BCRL, and how acupuncture might be used in the management of this condition. Acupuncture may be a promising complement or alternative to conventional lymphedema treatment methods, if its effectiveness is confirmed. Trial registration ClinicalTrials.gov NCT02803736 (Registered on October 31, 2016).

Additional file 1: of Effectiveness of acupuncture for breast cancer related lymphedema: protocol for a single-blind, sham-controlled, randomized, multicenter trial

Block Randomized Sequence. (PDF 83 kb