[Trend in acid deposition at Tieshanping, Chonging during 2001-2010].

Although the total emission of sulphure dioxide (SO2) was reduced by more than 10% in the Eleventh Five-Year-Plan (2006-2010) in China, the total emission of nitrogen oxides (NOx) in the same period kept increasing. In order to evaluate the effects of the emission changes on acid depostion, a ten-year monitoring on forest throughfall was carried out from 2001 to 2010 at Tieshanping, Chongqing in Southwestern China. The results indicated there was a significantly decreasing trend of sulphur deposition and an increasing trend of nitrogen deposition, which coincided well with the dicreasing trend of SO2 emission and increasing tread of NOx emission in Chongqing, respectively.

[Effects of simulated nitrogen deposition on organic matter leaching in forest soil].

The impact of nitrogen deposition on the dynamics of carbon pool in forest soil was studied through a field experiment at Tieshanping, Chongqing in Southwest China. The changes of dissolved organic matter (DOM) concentration in soil water in different soil layers were monitored for five years after addition of ammonium nitrate (NH4NO3) or sodium nitrate (NaNO3) at the same dose as the current nitrogen deposition to the forest floor. The results indicated that the concentration and flux of dissolved organic carbon (DOC) were increased in the first two years and then decreased by fertilizing.

[Effect of flue gas desulfurization gypsum application on remediation of acidified forest soil].

Effect of flue gas desulfurization gypsum (FGDG) application on remediation of a typical acidified forest soil was studied through field experiments at Tieshanping, Chongqing in southwest China for one year. To evaluate the effect and risk of FGDG application, pH value, major ions and heavy metal of soil water in different soil layers were observed dynamically, and heavy metal contained in soil and FGDG were measured. Results showed that Ca2+ and SO4(-2) concentration of soil water in FGDG plots increased with time, pH value was elevated slightly, and n(Ca)/n(Al) value of annual average increased from 2.