Fire-Induced Changes of Soil Structure: Implications for Soil Hydraulic Properties and Coupled Erosion by Water and Wind

火灾引起的土壤结构变化：对土壤水力特性和水风耦合侵蚀的影响

• 批准号: 0952272
• 负责人: David Shafer
• 金额: $ 2.97万
• 依托单位: Nevada System of Higher Education, Desert Research Institute
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-15 至 2011-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0952272&HistoricalAwards=false
• 关键词: Fire; Induced; Changes; Soil; Structure

RAPID: Fire-Induced Changes of Soil Structure: Implications for Soil Hydraulic Properties and Coupled Erosion by Water and WindDavid Shafer, Associate Research Professor, Division of Hydrologic Sciences, DRIMichael Young, Associate Research Professor, Division of Hydrologic Sciences, DRIDave DuBois, Associate Research Professor, Division of Atmospheric Sciences, DRIMarkus Berli, Assistant Research Professor, Division of Hydrologic Sciences, DRIScott Tyler, Research Professor, Department of Geological Sciences and Engineering, UNRThis award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). Project Abstract: The Gleason Controlled Burn, to be conducted near Ely, Nevada, provides an opportunity to quantify the effects of fire on soil structure, and to test hypotheses on how fire-induced changes in soil structure can lead to coupled water and wind erosion by collecting data at the same locations prior to and after the burn. The burn will be conducted by the U.S. Bureau of Land Management in August 2009. Because the burn is a planned event, pre- and post-burn measurements can be conducted on pre-determined sites. The funding awarded by NSF, along with internal funds from DRI, will be used to collect a set of pre-fire measurements. The area to be burned in the Gleason Fire has strongly-developed, coarse crumbled, soil structure in unburned areas. However, where other controlled burns have been done nearby, this structure has collapsed into a structureless soil, rich in fine particles that are most likely prone to erosion. Pre-fire measurements will include soil morphology and structure, water infiltration, air permeability, and wind-shear required to induce aeolian transport of soil particles. Hypotheses include: 1) the fire will destroy soil structure, increasing soil bulk density, and decreasing soil hydraulic conductivity and air permeability, a set of conditions that would increase the potential for soil erosion by water due to precipitation input; and, 2) the loss of soil structure will disaggregate soil material that would be more prone to suspension by wind at lower wind velocities, when compared to pre-burn conditions. Most studies on post-fire effects lack a true comparison to pre-fire conditions. This research will allow changes in soil structure to be quantitatively described and linked to post-fire hydraulic and aeolian transport properties that strongly influence the susceptibility of post-fire soil erosion. Although limited in scope, this research will provide the data needed for post-fire comparisons, and allow testing of some of the field and laboratory methods that the researchers will propose to use in a more comprehensive proposal to NSF on pre- and post-fire soil properties and erosion potential. The follow-on proposal will include collection of post-fire data from the Gleason Fire.

快速：火灾引起的土壤结构变化：水文科学系副教授david Shafer，水文科学系副教授michael Young，大气科学系副教授dave DuBois，水文科学系助理研究教授markus Berli，地质科学与工程系研究教授DRIScott Tyler，该奖项根据2009年美国复苏和再投资法案（公法111-5）资助。项目摘要：格里森控制燃烧（Gleason Controlled Burn）将在内华达州Ely附近进行，通过收集燃烧前后同一地点的数据，为量化火灾对土壤结构的影响提供了机会，并验证了火灾引起的土壤结构变化如何导致水蚀和风蚀耦合的假设。美国土地管理局将于2009年8月进行焚烧工作。因为燃烧是一个有计划的事件，燃烧前和燃烧后的测量可以在预先确定的地点进行。由NSF授予的资金，以及DRI的内部资金，将用于收集一套火灾前的测量数据。格里森火灾的受火区为未受火区发育较强的粗碎土结构。然而，在附近进行其他控制燃烧的地方，这种结构已经坍塌成一种无结构的土壤，富含最容易受到侵蚀的细颗粒。火灾前的测量将包括土壤形态和结构、水渗透、空气渗透性和引起土壤颗粒风成运输所需的风切变。假设包括：1)火灾会破坏土壤结构，增加土壤容重，降低土壤的导电性和透气性，这些条件会增加降水输入导致的土壤侵蚀潜力；2)与燃烧前相比，在较低风速下，土壤结构的损失会使土壤物质分解，更容易被风悬浮。大多数关于火灾后影响的研究缺乏与火灾前条件的真实比较。这项研究将允许定量描述土壤结构的变化，并将其与火灾后强烈影响火灾后土壤侵蚀敏感性的水力和风沙运输特性联系起来。虽然范围有限，但这项研究将提供火灾后比较所需的数据，并允许对一些现场和实验室方法进行测试，研究人员将在向美国国家科学基金会提交的关于火灾前后土壤特性和侵蚀潜力的更全面的提案中使用这些方法。后续提案将包括收集格里森火灾后的数据。