| DOI: | 10.2172/1147169
|
| 报告号: | DOE-UCB-0001470
|
| 报告题名: | Final report on "Modeling Diurnal Variations of California Land Biosphere CO2 Fluxes" |
| 作者: | Fung, Inez
|
| 出版年: | 2014
|
| 发表日期: | 2014-07-28
|
| 国家: | 美国
|
| 语种: | 英语
|
| 英文关键词: | carbon-climate feedback
; sap flow
; evapotranspiration
; soil moisture
|
| 中文主题词: | 生物圈
; 蒸散
; 土壤含水量
|
| 主题词: | BIOSPHERE
; EVAPOTRANSPIRATION
; SOIL MOISTURE
|
| 英文摘要: | In Mediterranean climates, the season of water availability (winter) is out of phase with the season of light availability and atmospheric demand for moisture (summer). Multi-year half-hourly observations of sap flow velocities in 26 evergreen trees in a small watershed in Northern California show that different species of evergreen trees have different seasonalities of transpiration: Douglas-firs respond immediately to the first winter rain, while Pacific madrones have peak transpiration in the dry summer. Using these observations, we have derived species-specific parameterization of normalized sap flow velocities in terms of insolation, vapor pressure deficit and near-surface soil moisture. A simple 1-D boundary layer model showed that afternoon temperatures may be higher by 1 degree Celsius in an area with Douglas-firs than with Pacific madrones. The results point to the need to develop a new representation of subsurface moisture, in particular pools beneath the organic soil mantle and the vadose zone. Our ongoing and future work includes coupling our new parameterization of transpiration with new representation of sub-surface moisture in saprolite and weathered bedrock. The results will be implemented in a regional climate model to explore vegetation-climate feedbacks, especially in the dry season. |
| URL: | http://www.osti.gov/scitech/servlets/purl/1147169
|
| Citation statistics: |
|
| 资源类型: | 研究报告
|
| 标识符: | http://119.78.100.158/handle/2HF3EXSE/41472
|
| Appears in Collections: | 过去全球变化的重建
影响、适应和脆弱性
科学计划与规划
气候变化与战略
全球变化的国际研究计划
气候减缓与适应
气候变化事实与影响
|
| File Name/ File Size |
Content Type |
Version |
Access |
License |
|
|---|
| 1147169.pdf（604KB） | 研究报告 | -- | 开放获取 | | View
Download
|
|
| Recommended Citation: | |
Fung, Inez. Final report on "Modeling Diurnal Variations of California Land Biosphere CO2 Fluxes". 2014-01-01.
|
|
|