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Characteristics and genesis of two strongly weathered soils in Samar, Philippines

Ian A. Navarrete A C , Victor B. Asio A D , Reinhold Jahn B and Kiyoshi Tsutsuki C

A Department of Agronomy and Soil Science, Leyte State University, Baybay, Leyte 6521-A, Philippines.

B Institute of Soil Science and Plant Nutrition, Martin-Luther University Halle-Wittenberg, Weidenplan 14, D-06108 Halle (Saale), Germany.

C Laboratory of Environmental Soil Science, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho 080-8555, Japan.

D Corresponding author. Email:

Australian Journal of Soil Research 45(3) 153-163
Submitted: 3 August 2006  Accepted: 14 March 2007   Published: 18 May 2007


Very limited data have been published on the nature of strongly weathered soils in geologically young humid tropical islands. The study evaluated the characteristics and formation of 2 strongly weathered soils in the island of Samar, Philippines, one developed from slate (Bagacay soil) and the other from ultrabasic rock (Salcedo soil). Results revealed that the soils have generally similar morphological characteristics, particularly in terms of colour (2.5 YR-10 R), solum thickness (>5.0 m), and structure (granular to subangular blocky), although the Salcedo soil has much higher clay content than the Bagacay soil. Both soils have similar chemical properties (e.g. acidic, low exchangeable bases) except that the Salcedo soil has lower CEC values but higher exchangeable Na content, resulting in a higher base saturation. They also have high dithionite-extractable Fe contents and very low oxalate/dithionite ratios and are dominated by halloysite, kaolinite, gibbsite, goethite, hematite, and quartz in the clay fraction. Apparently as a result of its more weatherable ultrabasic parent rock and more stable geomorphic surface, the Salcedo soil shows more advanced weathering and soil development than the Bagacay soil. Salcedo soil is classified as Haplic Ferralsol (Dystric, Clayic, Rhodic) in the World Reference Base or very fine, sesquic, isohyperthermic, Rhodic Hapludox in the Soil Taxonomy. Bagacay soil is a Haplic Acrisol (Alumic, Hyperdystric, Clayic, Rhodic) or fine, kaolinitic, isohyperthermic, Typic Paleudult. The Salcedo soil has very high Ni and Cr contents inherited from its ultrabasic parent material. The study reveals that on the geologically young humid tropical island of Samar, the characteristics and genesis of strongly weathered soils are greatly affected by the geochemical characteristic of the parent rock material.

Additional keywords: Oxisols, Ultisols, tropical island soils, ultrabasic rocks, slate.


Alcala AC (1997) Keynote address. In ‘Proceedings of International Conference on Reforestation with Philippine Species’. (Eds J Margraf, F Goeltenboth, P Milan) pp. 7–16. (ViSCA-GTZ Ecology Project: Baybay, Leyte, Philippines)

Asio VB (1996) Characteristics, weathering, formation, and degradation of soils from volcanic rocks in Leyte, Philippines. Hohenheimer Bodenkundliche Hefte, Vol. 33, Stuttgart.

Asio VB Cabunos CC Chen ZS 2006 Morphology, physiochemical characteristics and fertility of soils from Quaternary limestone in Leyte Philippines. Soil Science 171 648 661 doi:10.1097/

Balbino LC Bruand A Brossard M Grimaldi M Hajnos M Guimares MF 2002 Changes in porosity and microaggregates in clayey Ferralsols of the Brazilian Cerrado on clearing for pasture. European Journal of Soil Science 53 219 230 doi:10.1046/j.1365-2389.2002.00446.x

Beinroth FH 1982 Some highly weathered soils of Puerto Rico. 1. Morphology, formation and classification. Geoderma 27 1 73 doi:10.1016/0016-7061(82)90047-7

Blakemore LC , Searle PL , Daly BK (1987) Methods for chemical analysis of soils. New Zealand Soil Bureau of Scientific Report 80, Lower Hutt, NZ.

Blume HP Schwertmann U 1969 Genetic evaluation of profile distribution of aluminum, iron and manganese oxides. Soil Science Society of America Proceedings 33 438 444

Chang CP Wang Z McBride J Liu CH 2005 Annual cycles of Southeast Asia-maritime continent rainfall and the asymmetric monsoon transition. Journal of Climate 18 287 301

Chesworth W 1973 a The residua system of chemical weathering: a model for the chemical breakdown of silicate rocks at the surface of the earth. Journal of Soil Science 24 69 81 doi:10.1111/j.1365-2389.1973.tb00742.x

Chesworth W 1973 b The parent rock effect in the genesis of soil. Geoderma 10 215 225 doi:10.1016/0016-7061(73)90064-5

Dayot A (1988). Status of soil classification in the Philippines. In ‘Proceedings of the 14th International Forum on Soil Taxonomy and Agrotechnology Transfer’. (Philippines Council for Agricultural Resources Research and Development: Laguna, Philippines)

Driessen P , Deckers J , Spaargaren O , Nachtergaele F (2001) ‘Lecture notes on the major soils of the world.’ World Soil Resources Report 94. (FAO: Rome)

Driessen PM , Dudal R (1991) ‘The major soils of the world. Lecture notes on their geography, formation, properties and use.’ (AUW and KUL: The Netherlands)

Dudal R (2003) Evolving concepts in tropical soil science: the humid tropics. In ‘Evolution of tropical soil science: past and future’. (Ed. G Stoop) pp. 15–38. (Royal Academy of Overseas Sciences: Brussels)

Ellis AS Johnson TM Bullen TD 2002 Chromium isotope and the fate of hexavalent chromium in the environment. Science 295 2060 2062 doi:10.1126/science.1068368

FAO (1988) ‘Soil map of the world. Revised legend.’ (FAO: Rome)

FAO (2006) Guidelines for soil description.’ 4th edn (FAO: Rome)

Garrity DP (1993) Sustainable land-use systems for sloping uplands in Southeast Asia. In ‘Technologies for sustainable agriculture in the tropics’. (Eds J Ragland, R Lal) pp. 41–66. (ASA: Madison, WI)

Gracheva RG Targulian VO Zamotaev IV 2001 Time-dependent factors of soil and weathering mantle diversity in the humid tropics and subtropics: a concept of soil development and denudation. Quaternary International 78 3 10 doi:10.1016/S1040-6182(00)00110-5

Hall R 2002 Cenozoic geological and plate tectonic evolution of SE Asia and the SW Pacific: model and animation. Journal of Asian Earth Science 20 353 431 doi:10.1016/S1367-9120(01)00069-4

Heemsbergen DA Berg MP Loreau M Van Hal JR Faber JH Verhoef HA 2004 Biodiversity effects on soil processes explained by interspecific functional dissimilarity. Science 306 1019 1020 doi:10.1126/science.1101865

Huang WT (1962) ‘Petrology.’ (McGraw-Hill Book Co: New York)

International Soil Reference and Information Center (1995) ‘Procedures for soil analysis.’ (Ed. LP van Reeuwijk) (ISRIC: Wageningen, The Netherlands)

IUSS Working Group WRB (2006) World Reference Base for Soil Resources. World Soil Resources Report No. 103. FAO, Rome.

Jackson ML Tyler SA Willis AL Bourbeau GA Pennington RP 1948 Weathering sequence of clay-size minerals in soils and sediments. I. Fundamental generalizations. Journal of Physical and Colloid Chemistry 52 1237 1260 doi:10.1021/j150463a015

Jahn R , Asio VB (1998) Soils of the tropical forests of Leyte, Philippines. I. Weathering, soil characteristics, classification and site qualities. In ‘Soils of tropical forest ecosystems’. (Eds A Schulte, D Ruhiyat) pp. 29–36. (Springer Verlag: Berlin)

McKenzie RM 1980 Adsorption of lead and other heavy metals on oxides of manganese and iron. Australian Journal of Soil Research 18 61 73 doi:10.1071/SR9800061

Mekaru T Uehara G 1972 Anion adsorption in ferruginous tropical soils. Soil Science Society of America Proceedings 36 296 300

Mizota C , Van Reeuwijk LP (1989) Clay mineralogy and chemistry of soils formed in volcanic material in diverse climatic regions. ISRIC, Soil Monograph 2, Wageningen.

Mohr ECJ , Van Baren FA , Van Schuylenborgh J (1972) ‘Tropical soils. A comprehensive study of their genesis.’ (Mouton-Ichtiar-Van Hoeve: The Hague)

Moormann FR (1972) Soil microvariability. In ‘Soils of the humid tropics’. pp. 45–49. (National Academy of Science: Washington, DC)

Myers N Mittermeier RA Mittermeier CG da Fonseca GAB Kent J 2000 Biodiversity hotspots for conservation priorities. Nature 403 853 858

Nakashizuka T 2004 The role of biodiversity in Asian forests. Journal of Forest Research 9 293 298 doi:10.1007/s10310-004-0113-z

Quantin P (1990) Specificity of the halloysite-rich tropical and subtropical soils. In ‘14th International Congress of Soil Science’. Japan, Vol. VII. (IUSS)

Sanchez PA (1976) ‘Properties and management of soils in the tropics.’ (Wiley: New York)

Scheffer F , Schachtschabel P (1992) ‘Lehrbuch der Bodenkunde (13. Auflage).’ (Ferdinand Enke Verlag: Stuttgart)

Schlichting E , Blume HP , Stahr K (1995) ‘Bodenkundliches practikum.’ 2nd edn (Blackwell: Berlin)

Schulze DG (1989) An introduction to soil mineralogy. In ‘Minerals in soil environments’. 2nd edn, SSS Book Series 1. (Eds JB Dixon, SB Weed) pp. 1–33. (SSSA: Madison, WI)

Schwertmann U , Taylor RM (1977) Iron oxides. In ‘Minerals in soil environments’. (Eds JB Dixon, SB Weed) pp. 145–180. (ASA: Madison, WI)

Simon JD , Natividad NM , Amaba RM , Demen TP (1975) ‘Soil survey of Samar Provinces, Philippines.’ (Bureau of Print: Manila)

Soil and Land Resources Appraisal and Training Project Philippines (1977) Samar Island: Reconnaissance Land Resources Survey of Priority Strips for Integrated Rural Development. Bureau of Soils, United Nations Development Program and FAO, Manila.

Soil Survey Staff (2003) ‘Keys to Soil Taxonomy.’ 9th edn (USDA-Natural Resources Conservation Service, National Soil Survey Center: Lincoln, NI)

Stolbovoy VS 1992 Current problems in the study of tropical soils. Soviet Soil Science 24 1 15

Stoops G (2003) Introduction. In ‘Evolution of tropical soil science: past and future’. (Ed. G Stoops) (Royal Academy of Overseas Sciences: Brussels)

Tejedor Salguero ML Mendoza CJ Rodriguez AR Caldas EF 1985 Polygenesis on deeply weathered Pliocene basalt, Gomera (Canary Islands): from ferrallitization to salinization. Catena Supplement 7 131 151

Theng BKG 1991 Soil science in the tropics—the next 75 years. Soil Science 151 76 90

Thomas GW (1982) Exchangeable cations. In ‘Methods of soil analysis. Part 2. Chemical and microbiological properties’. 2nd edn (Ed. AL Page) pp. 159–165. (ASA-SSSA: Madison, WI)

Tiller KG Gerth J Brummer G 1984 The relative affinities of Cd, Ni and Zn for different soil clay fractions and goethite. Geoderma 34 17 35 doi:10.1016/0016-7061(84)90003-X

Verstappen HTh 1997 The effect of climatic change on southeast Asian geomorphology. Journal of Quaternary Science 12 413 418 doi:10.1002/(SICI)1099-1417(199709/10)12:5<413::AID-JQS324>3.0.CO;2-P

Yaalon D (1983) Climate, time, and soil development. In ‘Pedogenesis and Soil Taxonomy I: Concepts and interactions’. (Eds LP Wilding, NE Smeck, GF Hall) pp. 233–251. (Elsevier: Amsterdam)

Zikeli S Asio VB Jahn R 2000 Nutrient status of soils in the rainforest of Mt. Pangasugan, Leyte, Philippines. Annals of Tropical Research 22 78 88

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