M. Streeter, Keith E. Schilling, Thomas Stoeffler, Elliot Anderson
{"title":"爱荷华州农业河流排入防洪水库形成的三角洲沉积学","authors":"M. Streeter, Keith E. Schilling, Thomas Stoeffler, Elliot Anderson","doi":"10.1002/rra.4326","DOIUrl":null,"url":null,"abstract":"River deltas are ecologically critical landscape components and are responsible as habitats for millions of people, wildlife, and plant communities. Deltas store vast quantities of eroded nutrient‐rich sediment and play a significant role in water quality management through nutrient cycling and storage. Many studies have been conducted in marine and tidal delta environments that characterize the sedimentology and geomorphic characteristics of these relatively young landscapes. However, little work has been completed in even younger inland reservoir deltas. This study characterized the sediments and geomorphology of the growing delta forming at the outlet of the Des Moines River into Red Rock Reservoir in south‐central Iowa and discussed the implications of the lower delta sediment and topographic characteristics in terms of sediment and nutrient storage, and the potential impact of the delta on other hydroecological factors. We found that the ca. 30‐year‐old lower delta is storing up to 60% of the contributing watershed's eroded sediment and total carbon, with total sediment depths of ca. 9 m across the 755‐ha area. Further, we identified two major geomorphic landscape positions within the lower delta that were categorized as distributary channels and delta plains. Sedimentological differences in these microscale landscape positions were identified. Sand content was greater at lowest distributary channel elevations and at the highest plain elevations whereas silt dominated the elevation range between these two extremes. The zone of silt accumulation corresponds to the range in elevation associated with normal lake level management. The silt‐dominated area is regularly inundated and covered with a variety of emergent vegetation and is the zone of critical importance for waterbird habitat and nutrient‐processing capacity.","PeriodicalId":21513,"journal":{"name":"River Research and Applications","volume":null,"pages":null},"PeriodicalIF":1.7000,"publicationDate":"2024-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Sedimentology of a delta formed by agricultural river discharge into a flood‐control reservoir, Iowa\",\"authors\":\"M. Streeter, Keith E. Schilling, Thomas Stoeffler, Elliot Anderson\",\"doi\":\"10.1002/rra.4326\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"River deltas are ecologically critical landscape components and are responsible as habitats for millions of people, wildlife, and plant communities. Deltas store vast quantities of eroded nutrient‐rich sediment and play a significant role in water quality management through nutrient cycling and storage. Many studies have been conducted in marine and tidal delta environments that characterize the sedimentology and geomorphic characteristics of these relatively young landscapes. However, little work has been completed in even younger inland reservoir deltas. This study characterized the sediments and geomorphology of the growing delta forming at the outlet of the Des Moines River into Red Rock Reservoir in south‐central Iowa and discussed the implications of the lower delta sediment and topographic characteristics in terms of sediment and nutrient storage, and the potential impact of the delta on other hydroecological factors. We found that the ca. 30‐year‐old lower delta is storing up to 60% of the contributing watershed's eroded sediment and total carbon, with total sediment depths of ca. 9 m across the 755‐ha area. Further, we identified two major geomorphic landscape positions within the lower delta that were categorized as distributary channels and delta plains. Sedimentological differences in these microscale landscape positions were identified. Sand content was greater at lowest distributary channel elevations and at the highest plain elevations whereas silt dominated the elevation range between these two extremes. The zone of silt accumulation corresponds to the range in elevation associated with normal lake level management. The silt‐dominated area is regularly inundated and covered with a variety of emergent vegetation and is the zone of critical importance for waterbird habitat and nutrient‐processing capacity.\",\"PeriodicalId\":21513,\"journal\":{\"name\":\"River Research and Applications\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":1.7000,\"publicationDate\":\"2024-05-23\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"River Research and Applications\",\"FirstCategoryId\":\"93\",\"ListUrlMain\":\"https://doi.org/10.1002/rra.4326\",\"RegionNum\":4,\"RegionCategory\":\"环境科学与生态学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q4\",\"JCRName\":\"ENVIRONMENTAL SCIENCES\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"River Research and Applications","FirstCategoryId":"93","ListUrlMain":"https://doi.org/10.1002/rra.4326","RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"ENVIRONMENTAL SCIENCES","Score":null,"Total":0}
Sedimentology of a delta formed by agricultural river discharge into a flood‐control reservoir, Iowa
River deltas are ecologically critical landscape components and are responsible as habitats for millions of people, wildlife, and plant communities. Deltas store vast quantities of eroded nutrient‐rich sediment and play a significant role in water quality management through nutrient cycling and storage. Many studies have been conducted in marine and tidal delta environments that characterize the sedimentology and geomorphic characteristics of these relatively young landscapes. However, little work has been completed in even younger inland reservoir deltas. This study characterized the sediments and geomorphology of the growing delta forming at the outlet of the Des Moines River into Red Rock Reservoir in south‐central Iowa and discussed the implications of the lower delta sediment and topographic characteristics in terms of sediment and nutrient storage, and the potential impact of the delta on other hydroecological factors. We found that the ca. 30‐year‐old lower delta is storing up to 60% of the contributing watershed's eroded sediment and total carbon, with total sediment depths of ca. 9 m across the 755‐ha area. Further, we identified two major geomorphic landscape positions within the lower delta that were categorized as distributary channels and delta plains. Sedimentological differences in these microscale landscape positions were identified. Sand content was greater at lowest distributary channel elevations and at the highest plain elevations whereas silt dominated the elevation range between these two extremes. The zone of silt accumulation corresponds to the range in elevation associated with normal lake level management. The silt‐dominated area is regularly inundated and covered with a variety of emergent vegetation and is the zone of critical importance for waterbird habitat and nutrient‐processing capacity.
期刊介绍:
River Research and Applications , previously published as Regulated Rivers: Research and Management (1987-2001), is an international journal dedicated to the promotion of basic and applied scientific research on rivers. The journal publishes original scientific and technical papers on biological, ecological, geomorphological, hydrological, engineering and geographical aspects related to rivers in both the developed and developing world. Papers showing how basic studies and new science can be of use in applied problems associated with river management, regulation and restoration are encouraged as is interdisciplinary research concerned directly or indirectly with river management problems.