On the contrary,the average concentration of ammonia nitrogen are low in summer,In space,concentration distribution of different species of nitrogen shows structural features and stochastic character,smaller-scale effects can be ignored for conversion process of species of nitrogen,spatial correlation is very strong for all different species of nitrogen.

Effects of nitrogen form and rate on nitrate and nitrite content in flue-cured tobacco;

Effects of nitrogen form and baking on tobacco-specific nitrosmaines (TSNA) and precursor;

Effects of nitrogen forms and solution concentration on growth of Limonium bicolor L.;

In order to recognize the concentrations changes during the alga bloom and estimate the diffuse flux of inorganic nitrogen at the sediment –water interface, dissoluble nitrogen forms in the overlying water and surface sediment pore water from eight sites of Chaohu Lake were investigated and analysized from April to October in 2008.

Effects of nitrogen forms on rhizosphere microorganisms and soil enzyme activity under cultivation of contrasting wheat cultivars during booting and grain filling period;

Effect of nitrogen forms on growth and quality of‘Niitaka’pear;

Effects of nitrogen forms on root characteristics in wheat;

Effects of different nitrogen forms on cadmium accumulation of Sedum alfredii Hance;

Through analysis on chemistry properties of various nitrogen forms in compound fertilizers,some problems existing in determination of total nitrogen content in compound fertilizer are solved,and the qualitative analysis of nitrogen form and its key points is also presented for a reference in determination of compound fertilizer.

Pot experiment was carried out to study the effect of different nutrient levels and nitrogen forms on the growth, nutrient uptake, partitioning, and potassium flow within flue-cured tobacco plants.