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Predicton of soil erosion in the Northern Thailand using physical model / by Naree Suddhapreda

By:

Sudhapreda, Naree [author]

Contributor(s):

Paningbatan, Eduardo P [adviser]

Material type: Text

TextLanguage: English Publication details: Los Baños, Laguna : 1987. Cavite State University- Main Campus,Description: 196 pages : illustrations ; 28 cmContent type:

text

Media type:

unmediated

Carrier type:

volume

Subject(s):

DDC classification:

631.45 Su2 1987

Online resources:

Click here to view thesis abstract and table of contents

Abstract: SUDDHAPREDA, NAREE. University of the Philippines at Los Banos, October, 1987. Prediction of Soil Erosion in Northern Thailand Using a 8 Physical Model. Major Professor: Dr. Eduardo P. Paningbatan, Jr. Experiments were conducted to study the effects of rainfall intensity, slope steepness and crop cover on runoff and soil loss. The physical model of estimating soil erosion as developed by Rose , Barry and Sander (1983) was evaluated, and the simplified equation was used in predicting soil erosion of two watersheds (Haui Pong and Nam Poi) in Chiang Mai, Northern Thailand. The treatments involved two soil types (Korat sandy loam and Pak Chong clay loam, both belonging to Oxic Paleustults); three levels of rainfall intensity (60, 90, and 120 mm/hr); four levels of slope steepness (0, 5, 10, and 20 per cent); and two kinds of cover crops (corn and soybean). Rainfall intensities were controlled using a rainfall simulator and slope steepness using a slope~adjustable soil trough. Runoff, sediment concentration and soil loss increased with increase in rainfall intensity and slope. Sediment concentration was high at the earlier stage of crop growth, but this exponentially decreased as the vegetative cover increased with time. The sediment Concentration in Pak Chong clay loam was generally lesser than in Korat sandy loam particularly under higher rainfall, steeper slope and lesser vegetative cover, indicating that the latter soil is more erodible than the former. The physical model yielded a good prediction of soil erosion. In both soils, under bare or cropped soil surface conditions, the correlations of the predicted and the measured soil loss on different combinations of slope and rainfall intensity were highly significant. In the two watersheds, the predicted soil erosion values in the forest, and the well-vegetated and level agricultural lands were less than 4 tons/ha/yr. On the other hand, the hilly areas utilized for shifting cultivation gave the highest value of 1208 tons/ha/yr.

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Holdings ( 1 )
Title notes ( 4 )

Holdings
Item type	Current library	Collection	Call number	Materials specified	URL	Status	Notes	Date due	Barcode
Theses / Manuscripts	Ladislao N. Diwa Memorial Library Theses Section	Non-fiction	631.45 Su2 1987 (Browse shelf(Opens below))		Link to resource	Room use only	T-1490		00002344

Thesis (Ph.D. - - Soil Science) University of the Philippines, College, Laguna.

Includes bibliographical references.

SUDDHAPREDA, NAREE. University of the Philippines at Los Banos, October, 1987. Prediction of Soil Erosion in Northern Thailand Using a 8 Physical Model. Major Professor: Dr. Eduardo P. Paningbatan, Jr.

Experiments were conducted to study the effects of rainfall intensity, slope steepness and crop cover on runoff and soil loss. The physical model of estimating soil erosion as developed by Rose , Barry and Sander (1983) was evaluated, and the simplified equation was used in predicting soil erosion of two watersheds (Haui Pong and Nam Poi) in Chiang Mai, Northern Thailand.

The treatments involved two soil types (Korat sandy loam and Pak Chong clay loam, both belonging to Oxic Paleustults); three levels of rainfall intensity (60, 90, and 120 mm/hr); four levels of slope steepness (0, 5, 10, and 20 per cent); and two kinds of cover crops (corn and soybean). Rainfall intensities were controlled using a rainfall simulator and slope steepness using a slope~adjustable soil trough.

Runoff, sediment concentration and soil loss increased with increase in rainfall intensity and slope. Sediment concentration was high at the earlier stage of crop growth, but this exponentially decreased as the vegetative cover increased with time. The sediment Concentration in Pak Chong clay loam was generally lesser than in Korat sandy loam particularly under higher rainfall, steeper slope and lesser vegetative cover, indicating that the latter soil is more erodible than the former.

The physical model yielded a good prediction of soil erosion. In both soils, under bare or cropped soil surface conditions, the correlations of the predicted and the measured soil loss on different combinations of slope and rainfall intensity were highly significant.

In the two watersheds, the predicted soil erosion values in the forest, and the well-vegetated and level agricultural lands were less than 4 tons/ha/yr. On the other hand, the hilly areas utilized for shifting cultivation gave the highest value of 1208 tons/ha/yr.

Submitted to the University Library 01/07/1994 T-1490