Dissolved inorganic nitrogen (DIN) , dissolved inorganic phosphorus (DIP) of surface water and other related environmental parameters (Salinity, DO, Chi a) were observed consecutively at two stations in the Xiamen Bay during No.

Based on the data collected in May 1996, this study summarizes the levels and distributions of dissolved inorganic nitrogen in Yalujiang estaury.

Based on the investigation data from the project “Research on the Dynamic of Seawater Circulation and Mass Long Term Transportation”, which was implemented in May 1998, the distribution patterns of dissolved inorganic nitrogen (DIN) in the Southern Yellow Sea in May were discussed.

Using a multi-layer soil column device,the effect of new nitrification inhibitor DMPP(3,4-dimethyl pyrazole phosphate) on nitrogen leaching was studied for understanding the nitrogen vertical transformation and lowering the nitrogen leaching losses.

There were fewer researches on nitrogen leaching in paddy rice field.

According to soil profile of nitrate nitrogen,ammonium nitrogen,organic matter and total nitrogen under different land uses patterns,effects of soil nitrogen leaching under different land uses in the loess hilly and gully region were discussed in detail,and proposals were gaven for local agricultural development.

Static absorption and soil column leaching methods were used to study ammonia volatilization and N leaching characteristics from six controlled/slowrelease fertilizers.