Effects of potassic fertilizer on crop growth in bushy sierozem：a long-term experiment in Hexi district of Gansu;

With the continual 22 year longterm location tests of soil fertility and fertilizer effect in the irrigated desert soil in the Gansu Corridor,and 4 year location tests on wheat and maize,the results show that for planting wheat/maize on band field,the annual fast release K and slow release K in soil decrease by 10.

The effect of fertilizer application on wheat seed content and production of coarse protein and protein amino acid are systematically studied based on the data of long term fertilizer location test in rotation culture.

Change features of soil available P in yellow fluvo-aquic soil for long-term stationary experiment;

Balance of soil K,changes of available K and effect of K fertilizer in different treatments (NP,NPK,MPK,MNPK)were studied according to the systematic data from long term stationary experiments in yellow fluvo aquic soil for 18 years.

Study on long-term experiment of crop rotation and fertilizationin the Loess PlateauI Ⅰ. Effect of crop rotation and continuous planting on soil enzyme activities;

Dynamics of total phosphorus and Olsen-P of soils without fertilization were studied with long-term experiment on eleven typical soils.

To find optimal management practices for increasing nitrogen use efficiency,a long-term experiment was established in 1989 including seven treatments.