Changes of several physico-chemical properties of paddy soils in Nagasaki prefecture [Japan]
1999
Inoue, K. (Nagasaki-ken. Agricultural and Forestry Experiment Station, Isahaya (Japan)) | Nagao, Y. | Nanba, N. | Kanda, S. | Nagata, H.
We were engaged in this research in order to analyze the present and the passing year changes of physico-chemical properties of paddy field soils in Nagasaki prefecture and we compared results in 1994 to 1998 (the fourth period) with those of 1979 to 1984 (the first period). (1) The efficient depth of topsoil was 12.6cm in average, shallow in 71% fields, there were gley, yellow, gray lowland, brown lowland soils in each length. (2) The pH value of soils was 5.8 in average, and there were not proper in 40% of fields. (3) The content of humus, total nitrogen, cation exchange capacity, exchangeable calcium, exchangeable magnesium, available nitrogen, available silicate and Mg/K balance decrease clearly comparing for the first period. (4) The content of exchange potassium, available phosphate and base saturation percentage of soil increase more than the first period. (5) The amount of compost applications decreased, but those of inorganic matter, such as phosphate fertilizer, calcium fertilizer and silicate fertilizer increased. (6) The applications of compost synthetically and certainly improve on physicochemical properties of paddy soil. (7) Based on these analytical results, we recommend plowing deeply, applying of matured compost and silicate fertilizer, and proper use of chemical fertilizer in soil management
显示更多 [+] 显示较少 [-]