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The efforts to utilize the agricultural land need a proper understanding of the soil characteristics. The soil characteristics themselves are influenced by the factors that regulate and control the soil forming and pedogenesis processes. The main soil forming factors in this study was the different ages and composition of parent materials from the eruption of Mt. Tangkuban Parahu in West Java. This research was done to comprehend the pedogenesis and to figure out the soil classifications that developed in two geological formations (Qyd and Qvu) and two ages of eruption (Holocene and Pleistocene) of Mt. Tangkuban Parahu. The study was conducted in Ciater, Subang Regency and Jatinangor, Sumedang Regency in West Java Province. The study consisted of four stages: preparation, field survey and soil sampling, laboratory analysis and presenting the report. The results showed that Pedon of Jatinangor consisted of three different stratifications of ages. The clay mineralogical composition was dominated by kaolinite, whereas mineralogical composition of the sandy fractions (heavy fractions) was augite-hypersthene. Pedon of Ciater also consists of three different stratifications of age. The clay mineralogical composition was dominated by allophane, while mineralogical compositions of the sandy fractions (heavy fractions) were green amphibole-hypersthene in the overlying horizons and amphibole-augite in the underlying horizons. The stage of soil formation on both pedon were cambic or viril. The soil classification according to Soil Taxonomy were Acrudoxic Durudands, medial over loamy-skeletal, isohyperthermic in Ciater Pedon and Fluventic Eutrudepts, fine, kaolinitic, isohyperthermic in Jatinangor Pedon.Key words: slow sand filter, activated carbon, silica sand, sand, gravel, zeolite

Kemampuan lahan merupakan komponen yang digunakan untuk menentukan kesesuaian potensi dengan penggunaan lahannya. Penggunaan lahan yang tidak sesuai dengan kemampuannya berpotensi mengalami degradasi lahan. Tujuan penelitian ini adalah memberikan informasi mengenai kemampuan lahan, faktor penentunya, dan memberikan arahan penggunaan lahan serta pengelolaannya secara tepat. Penelitian jenis survey ini menggunakan metode purposive sampling untuk pengamatan kondisi di lapangan dan pengambilan sampel. Data hasil pengamatan diolah dengan matching data kemampuan lahan dan uji statistik ANOVA dan korelasi untuk menemukan faktor yang paling menentukan kemampuan lahan di Ngadirojo. Hasil penelitian menunjukkan kemampuan lahan di Kecamatan Ngadirojo adalah III-l2.d3.b1, IV-d4, IV-l3 dan IV-l3.d4. Faktor yang menentukan kemampuan lahan di antaranya penggunaan lahan dan kedalaman tanah. Arahan penggunaan lahan yang dapat diterapkan berupa sawah, sawah dengan konservasi, dan agroforestry.

The existence of global warming, directly or indirectly, will have an impact on climate change which will threaten the productivity of cocoa plantations. This study aims to (1) determine the correlation between rainfall, relative humidity, and temperature to cocoa productivity and (2) determine the correlation between land suitability and cocoa productivity in Tulakan District, Pacitan Regency. The method used in this research was a descriptive exploratory method with a purposive sampling technique of collecting soil samples on land map units that have been determined based on various map overlays. There are five land map units (LMU) with a total area of 2.624 Ha with each LMU repeated three times. Regression correlation analysis was conducted to determine the relationship between rainfall and relative humidity on land suitability and cocoa productivity. The analysis showed that there was a negative correlation between rainfall and cocoa productivity (r = - 0.892, p <0.05), as well as relative humidity and cocoa productivity (r = - 0.950, p <0.05). There was a positive correlation between land suitability and cocoa productivity (r = 0.895, p < 0.05). Land map unit 1,2,3 were the best class of land suitability with the lowest limiting factor (relative humidity and available P), and it has high cocoa productivity. The higher rainfall and relative humidity will affect the lower cocoa productivity.