Perubahan sifat-sifat bahan sulfidik akibat pengeringan dan pencucian serta pengaruhnya terhadap kualitas air cucian

Abstract

Based on the topcgraphy, position, total area and the availability of water, the acid sul phate soils are potentially to be developed for agriculture development. However agriculture development on that soil is mostly un-success due to problem of acid sulphate as results of sulphidic materials oxidation in the solum. Naturally, the potentially acid sulphate soils are situated in the p r drainage condition, whereas the sulphidic materials are situated in the anaerobic zone and the pH value is nearly neutral. If the drainage improvement carried out carelessly, it causes the environment of the sulphidic material changes from anaerobic to aerobic condition. For that reason the sulphidic materials is oxidized and prduces acid that causes highly acidity of the environment and follows by dissolution of some toxic elements and decreasing the availability of some nutrition. There are some efforts to solve that problems, among others are combination of re-flooding and leaching. The objective of the re-flooding is to stop the oxidation of sulphidic materials, whereas of the leaching is to flushed out the toxic elements as the results of oxidation process. However the leaching process also leaches the soil nutrients, that causes decreasing the soil fertility. In addition the leachate has strong acidity and contains some toxic elements. If the lachate is disposed into the environments will cause some problems. For that reasons k i c information on the detail characteristics changes of the sulphidic materials due to drying, flooding and leaching and the charactenstic of the leachate are necessary in order to develop techniques of reclamation, rehabilitation, management of acid sulphate soils, and enviroflmental impacts management. Dealing with the above background, the aims of this study are to know the changes of the sulphidic material characteristics due to drying and leaching, to recognize the characteristics of the lechate and to identify the quantitative relationships of the characteristics of the sulphidic materials and the qua1 I ty of leachate with the duration of drying and leaching.

Ditinjau dari luas, letak, topografi, dan ketersediaan air, tanah sulfat masam sangat potensial untuk pengembangan pertanian. Namun pengembangan pertanian pada tanah tersebut sering mengalami kegagalan karena adanya permasalahan sulfat masam yang bersumber dari bahan sulfidik di dalam solum tanah tersebut yang teroksidasi.