KAJIAN SIFAT KIMIA TANAH SAWAH DENGAN POLA PERTANAMAN PADI SEMANGKA DI DESA AIR HITAM KECAMATAN LIMA PULUH KABUPATEN BATUBARA

Abstract

Rice and Watermelon cropping pattern has been always applied at Air Hitam Village, Lima Puluh Subdistrict, Batu Bara District. The selected cropping pattern was choosed because of rice production did not increase in rice and rice cropping pattern, and it will be expected that rice and watermelon cropping pattern will increase the farmer income. The difference in cropping pattern and supply of organic matter changes in soil properties of fields. The objective of this study was to know the changes in some chemical properties of paddy soil at Air Hitam Village, Lima Puluh Subdistrict, Batu Bara District which is lacated at about 18 m above sea level (asl). Parameters measured were pH using Electrometric method, organic carbon by using Walkley and Black method, available phosphorus by using Bray II method, exchangeable potassium NH4OAc with method, total-N by using Kjeldahl method and available SiO2 by using ammonium acetate extraction. The results of this study showed that rice and watermelon cropping pattern didn’t affect the paddy soil chemical properties including pH, organic carbon, total-N, available phosphorus, and exchangeable potassium, except soil available SiO2, is higher at rice and watermelon cropping pattern compared to that rice-rice cropping pattern. Key words : cropping system, soil chemical properties.