| 项目编号: | 1521224
|
| 项目名称: | Effects of Urbanization on Sources and Transport of Dissolved Inorganic Carbon in Watersheds |
| 作者: | Sujay Kaushal
|
| 承担单位: | University of Maryland College Park
|
| 批准年: | 2014
|
| 开始日期: | 2015-06-15
|
| 结束日期: | 2019-05-31
|
| 资助金额: | USD400201
|
| 资助来源: | US-NSF
|
| 项目类别: | Continuing grant
|
| 国家: | US
|
| 语种: | 英语
|
| 特色学科分类: | Geosciences - Earth Sciences
|
| 英文关键词: | transport
; dic
; source
; dic source
; stream
; urbanization
; inorganic carbon
; potential source
; coastal carbon cycle
; carbonate alkalinity
; research
; impact source
; watershed urbanization
; bicarbonate availability
; river
|
| 英文摘要: | Human activities have increased dissolved inorganic carbon (DIC) in streams and rivers, which impacts drinking water supplies across large regions of the U.S. Increased transport of DIC to surface waters complicates drinking water treatment, encourages algal growth, increases water hardness, and corrodes of water infrastructure, such as water mains and pipes. DIC also provides buffering capacity (it can act as an "antacid") in rivers and the coastal ocean. Agricultural and urban areas have the potential to increase DIC sources and transport because of agricultural liming, breakdown of concrete structures, and sewage leaks. However, previous research has not focused on urban areas. This project will investigate how agricultural and urban land uses impact sources, amounts, and transport of DIC in streams and how the sources change with storms and different land uses. It will compare the amount and sources of DIC transported to streams with forest reference conditions. The research will first "fingerprint" DIC sources (concrete, soils, wastewater, rocks, etc.) using state-of-the-art geochemical tracers. Then, it will estimate the ability of urban streams to retain DIC before it is transported to sensitive receiving waters, like Chesapeake Bay. This project will be one of the first to provide simultaneous information on sources and transport of DIC contributing to increased river alkalinization in the U.S. Results and outcomes will be important for predicting impacts of increasing land development on drinking water quality, estimating the effects on acidification of coastal oceans, informing urban watershed management, and restoring urban streams.
Concentrations of dissolved inorganic carbon (DIC) have increased in streams and rivers in the eastern U.S. The transport of DIC from watersheds to streams contributes to river alkalinization, which impacts on drinking water hardness, shifts the coastal carbon cycle, and increases bicarbonate availability for primary production. Some studies suggest that transport of DIC and carbonate alkalinity are significantly elevated in streams and rivers draining urbanized watersheds. Most work on DIC fate and transport has focused on forest and agricultural watersheds; so we know little about changes in sources and transport of DIC in urbanized watersheds. This research investigates 3 questions: 1) How does land use influence the amounts and hydrologic timing of DIC exports; 2) How do sources of DIC change with increasing urbanization and throughout storms; and 3) How does urbanization alter in-stream fate and transport of watershed DIC export? The research will: a) analyze concentrations and fluxes of DIC and other weathering products weekly in forest, agricultural, suburban, and urban watersheds at the Baltimore Long-Term Ecological Research (LTER) site; and b) estimate cumulative DIC distribution curves and changes in DIC export timings across the land-use gradient. Then, the research will: a) geochemically identify potential end members of stream DIC sources in watersheds of similar lithology (two forested and two suburban) using DIC delta 13C, major element geochemistry, and DIC speciation; b) evaluate shifts in DIC concentrations and potential sources during the evolution of storms in these same watersheds; and c) measure DIC uptake rates and transient storage using stream injections of 13C-labelled NaHCO3 in selected stream reaches. Expected outcomes will link watershed urbanization to changes in DIC dynamics as a function of land use, streamflow, and channelization and will elucidate mechanisms for increased river alkalinization. This will be one of the first projects to produce simultaneous information on the sources, transport, and fate of DIC in urban streams using integrated hydrologic and geochemical approaches. |
| 资源类型: | 项目
|
| 标识符: | http://119.78.100.158/handle/2HF3EXSE/94365
|
| Appears in Collections: | 影响、适应和脆弱性
气候减缓与适应
|
|
There are no files associated with this item.
|
| Recommended Citation: | |
Sujay Kaushal. Effects of Urbanization on Sources and Transport of Dissolved Inorganic Carbon in Watersheds. 2014-01-01.
|
|
|