[Study of soil physical characteristics of grumosol as the result of flooding]

English. Soil, which is always experiencing periodical flooding and so long enough; will face the sedimentation process. The flooding will effect on (a) the changing of air in the soil will be abstract and disturbance, (b) soil nutrients and (c) tend to the development of gley soil process, in turn it will have effect on the characteristics of soil physic. The aim of the research is to know the difference of the soil physic characteristics of grumosol due to once until four times flooding, and the production of paddy. The method used was a survey and the teacher of sampling used the random proportional stratified sampling. The result was shown that the more soil flooded there is the difference of the soil physic characteristics of grumusol, and there is the difference of the yield of paddy that is the tend to decrease from 13 ton/ha/year to 10 ton/ha/year. Soil structure shows that the level development is strong and the shape of the grumusol soil structure is sub angular with the size of grain arounded is 10 until 25 mm and the level of drainage is bad. To maintain the soil physic characteristics of grumusol soil and the production of paddy due to the flooding include the management of the soil such as the improvement of drainage, the application of crop rotation and the optimum of fertilizer application

Indonesian. Tanah yang sering mengalami pengendapan secara periodik dan dalam waktu yang cukup lama akan terjadi proses pengendapan sedimen. Genangan tersebut akan berpengaruh terhadap: (a) pertukaran udara dalam tanah terhambat dan terganggu, (b) unsur hara, (c) kecenderungan ke arah proses pembentukan gleisasi yang selanjutnya akan mempunyai pengaruh terhadap sifat-sifat fisik tanah. Penelitian in bertujuan untuk mengetahui perbedaan sifat-sifat fisik tanah grumusol akibat genangan satu kali sampai empat kali, serta produksi padi. Metode yang digunakan adalah metode survei dan teknik pengambilan sampel menggunakan stratified proportional random sampling. Hasil penelitian menunjukkan bahwa makin sering tergenang pada perbedaan sifat-sifat fisik tanah grumusol dan perbedaan produksi padi yang cenderung menurun. Struktur tanah menunjukkan tingkat perkembangan yang kuat dan bentuk struktur tanah grumusol bersudut dengan ukuran butir antara 10 sampai 25 mm serta drainase tingkat jelek. Untuk mempertahankn sifay-sifat fisika tanah grumusol dan produksi padi akibat genangan tersebut meliputi pengelolaan tanah antara lain perbaikan drainase, penerapan pergiliran tanaman dan pemupukan yang optimal