Ammonia-nitrogen (NH3 -N) loss from agriculture decreases crop yield potential and environ-mental quality. Incorporating animal manures by chisel plowing (CP) can reduce NH3 loss but may increase erosion and compaction potential compared to lower disturbance methods. Vertical tillage (VT) is designed to reduce disturbance and conserve more crop residue than CP, however its effect on NH3 loss from manure application is largely unknown. Six trials in corn production systems were conducted to evaluate the impacts of manure incorporation method (CP, VT, or broadcast) and weather conditions on NH3-N concentrations during 2013 to 2016 at a research farm in central Wisconsin, USA. Passive samplers were used to measure NH3-N concentrations at 30-cm above the ground during the first 0 to 24 and 24 to 48 hr post-application/incorporation. Average NH3 -N concentrations for CP and VT were 44 to 86% of surface broadcast and similar for most trials, while crop residue coverage was greater for VT than CP (39 and 22% of control plots, respectively). Concentrations of NH3 -N were correlated with the amount of plot area covered by manure for the first (r = 0.56, P<0.0001) and second measurement periods (r = 0.85, P<0.0001). Results show that VT had comparable NH3-N concentration reductions to CP while conserving more crop residue.

This paper intends to examine whether a company’s policy of dividend would impact or influence the price fluctuation of respective common stock in the designated stock market particularly in Hong Kong. Hence, there are 354 companies in Hong Kong which are all listed company on the Stock Exchange of Hong Kong (HKEX), were chosen as sample data for analysis with their audited financial information ranged from 2001 to 2020. Two proxies, the yield and the ratio of pay-out of dividend were widely adopted for the measurement of the effect of dividend policy and the possible influence on the volatility of respective common stock price by employing two statistical models, which are the model of fixed and random effects to provide accurate regression coefficients. With the results from the model of fixed effects, the yield and the pay-out ratio of dividend have been found statistically associated to the price volatilization of respective common stock in Hong Kong. The statical results in this study also find the yield and the ratio of pay-out of dividend are apparently and negatively associated to the price volatilization of respective common stock in Hong Kong. The research outcomes will be a reference for further study on different variables may have effects or volatilize the price of common stock price particularly in Hong Kong capital market.