The Study On The Geographical Equilibrium Point Of Soil Potassium

Potassium in soil is the main resource nutrients of K that plant needed.Rencently research indicates that the available K in soil is decreasing, which is harmful for the sustainable use of soil, land, and agriculture.The sustainable development is the subject of the world.The study on the geographical equilibrium point of the soil potassium is the base of the sustainable land use. Because of this, the author researches the theory and method of the geographical equilibrium point of the soil potassium based on the study of others with the case of Aquent in xiongxian county of Hebei provience.1. The concepts about geographical equilibrium point of K were putted out, which will provide a refenrence for the study of the equilibrium point of other nutrients.2. The geographical equilibrium point of K is existed, limited, regular, relative, which has been verified.3. The change of sioil available K was forecasted, which indicates that the two methods can be used in calculating the geographical equilibrium point of K.4. The forecast of the geographical equilibrium point of K has been made using different methods.The result indicates that the order of the geographical equilibrium point of K is: total k>l/2k>-k, ck.5. The result indicates that the geographical equilibrium point of 1/2K is the most suitable one for the sustainable use of land and fertilizer resource.6. The change of sioil available K was analized, which result indicates that the change of the geographical equilibrium point of K increases from the seeding of wheat and corn,and decrease from jointing.