Hydrologic response of an East Texas pine forest to intensive management practices /
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| Other Authors: | , , |
| Format: | Thesis Book |
| Language: | English |
| Published: |
1992.
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| Subjects: | |
| Online Access: | Link to OAKTrust copy |
| Abstract: | The overall objective of this study was to develop a quantitative and physically based understanding of how site management affects an upland pine forest hydrologic balance. To achieve this objective, four interrelated studies were concluded: (1) estimation of total foliage area, (2) documentation of soil moisture depletion patterns, (3) estimation of interception loss, and (4) estimation of runoff, deep drainage, and consumptive water use by the mature and immature pines. Specific leaf area (SLA), functional surface area, and leaf area index (LAI) were calculated. LAI for trees grown in the sheared, roller-chopped, and mature forest sites were 10.2, 7.4, and 9.17 m^2 m^-2, respectively. Estimated SLAs for the sheared, roller-chopped, and mature forest sites were 107.8, 102.9, and 229.0 cm^2g^-1, respectively. Soil moisture drawdown coincided with the growing season with highest depletion rates occurring during the summer. In summer, the available soil moisture in the top 0.28 m soil profile was completely exhausted. Highest deficits recorded were 458, 375, and 331 mm of water in the mature, roller-chopped, and sheared watersheds, respectively. Soil moisture recharge occurred during the cool season frontal storms. The general pattern of soil moisture accretion and depletion was repeated each year, but the exact timing of the trend was dependent on the timing of the rainfall. Average estimated throughfall for the sheared, roller-chopped, and mature forest were 67, 73, and 80% of the total rainfall. Stemflow as a percentage of gross rainfall was 0.3, 6.4, and 9.2% for the mature, roller-chopped, and sheared sites, respectively. Interception losses as a percentage of gross rainfall were 23.8, 20.7, and 19.7% for the sheared, roller-chopped, and mature sites, respectively. Runoff from the sheared, roller-chopped, and mature lysimeters were 24.0, 12.3, and 3.5% of the total rainfall, respectively. In the same order, deep drainage was 4.5, 5.4, and 7.4% of the total rainfall. ET as a percentage of the total rainfall for the study period was 71.5, 82.3, and 89.1% for the sheared, roller-chopped, and mature forest, respectively. ET for the growing season was highest in the sheared lysimeters (5.8 mm day^-1). ET in the mature and roller-chopped lysimeters was about the same (about 4.3 mm day^-1). |
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| Item Description: | Typescript (photocopy). Vita. "Major subject: Range Science." |
| Physical Description: | xix, 250 leaves : illustrations ; 29 cm |
| Bibliography: | Includes bibliographical references. |