Article
Engineering, Environmental
Seung-Hee Kim, Dong-Hun Lee, Min-Seob Kim, Han-Pil Rhee, Jin Hur, Kyung-Hoon Shin
Summary: In this study, an integrated framework was validated to effectively manage nitrate loading in complex river systems through quantitative estimation of nitrate sources. The isotopic compositions of nitrates showed different ranges among land-use types, reflecting different nitrate sources within watersheds. Hydrological conditions, such as water discharge, partially controlled total nitrate loads. Sewage transport near urban boundaries showed unique enhancement and increased total nitrate load in downstream areas. The isotopic and model-based nitrate fluxes showed good correlation for urban sources but poor correlation for agriculture-dominated land use.
Article
Biodiversity Conservation
Zhang Xingyuan, Li Fawen, Zhao Yong
Summary: This study focuses on the connectivity of river networks in the Haihe River basin in China. By constructing a graphic model, the researchers analyze the changes in river network structure and their impact on connectivity. The results show that the river network evolves into a small-world network, which improves its efficiency and functionality but leads to decreased connectivity. The structural changes also result in spatial and temporal differences in hydrological connectivity, which further limits the function of the river system.
ECOLOGICAL INDICATORS
(2023)
Article
Environmental Sciences
Alicia Sendrowski, Edward Castaneda-Moya, Robert Twilley, Paola Passalacqua
Summary: This study analyzed the influence of various external and internal drivers on nitrate variability in a coastal deltaic wetland in Louisiana, identifying that external drivers work together to influence nitrate transport and that patterns of hydrological and sediment connectivity change over time, influencing the emergence of functional zones.
JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES
(2021)
Article
Ecology
XueHong Wang, YuHan Zou, Tao Zhu, Bo Guan, JiSong Yang, JunBao Yu
Summary: Blocking of hydrological connectivity has significant impacts on sediment deposition, water and salinity, affecting plant germination, growth, and development in delta wetlands. Moderate salinity and fluctuating water levels are suitable for seed germination and plant growth, while extreme salinity and high water levels are detrimental. Water can offset the hazards of high salinity concentrations for the halophyte species.
FRONTIERS IN ECOLOGY AND EVOLUTION
(2022)
Article
Engineering, Environmental
Wenjing Liu, Hao Jiang, Xiao Guo, Yuanchuan Li, Zhifang Xu
Summary: The study in the Tibetan Plateau revealed the significant correlation between nitrate (NO3-) flux and discharge, indicating the presence of a potential NO3- source counteracting the diluting effects during the rainy season. Soil sources were found to be the primary contributors to NO3- flux, with significant seasonal variations driven by hydrological conditions. A conceptual model integrating anthropogenic and climatic factors was proposed to classify NO3- export mechanisms into transport-limited and generation-limited regimes.
Article
Environmental Sciences
Chengjie Xie, Baoshan Cui, Zhonghua Ning, Shuling Yu, Tian Xie
Summary: River deltas, formed by water and sediment interaction, are valuable ecosystems on Earth. Increasing fragmentation of deltas is largely caused by human activities disrupting longitudinal hydrological connectivity. This study investigated the spatiotemporal variation in hydrological connectivity in the Yellow River Delta (YRD) and found that it is closely related to tidal channel network geometry and research scale. The results provide insights for the restoration of damaged wetlands.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Oceanography
Kexin Chen, Pifu Cong, Limei Qu, Shuxiu Liang, Zhaochen Sun, Jianbo Han
Summary: This study quantitatively analyzed the hydrological connectivity in the Liaohe Delta wetland using multispectral Landsat series datasets, and defined identification criteria for connectivity or blockage. The results showed that water area has slightly decreased over the past 35 years, and connectivity blockage has occurred. Human activities have become the main factor in the blockage of connectivity in the Liaohe Delta wetland since 2006. This study provides valuable insights for the conservation and restoration of hydrological connectivity in the Liaohe Delta wetland.
OCEAN & COASTAL MANAGEMENT
(2023)
Article
Environmental Sciences
Jiuge Feng, Jinfeng Liang, Qianwei Li, Xiaoya Zhang, Yi Yue, Junqin Gao
Summary: The study explored the dynamics of hydrological connectivity and its impact on soil carbon pool in the Yellow River Delta. Results showed an increase in hydrological connectivity in certain areas, leading to significant changes in soil carbon storage. Appropriate hydrological connectivity was found to effectively promote soil carbon storage in the region.
CHINESE GEOGRAPHICAL SCIENCE
(2021)
Article
Engineering, Civil
Cai Li, Fu-Jun Yue, Jun Zhong, Sen Xu, Si-Liang Li
Summary: A comprehensive understanding of nitrate dynamics in rivers is crucial for effective nitrogen management, particularly in karst regions where high leaching of nitrate poses potential risks to environmental quality. However, the identification of nitrate sources and transformation pathways in karst rivers is limited. This study used a combination of hydro-geochemical parameters to identify nitrate sources and dynamics in the Wujiang River, showing that nitrates were mainly transported through the soil/epikarst pathway in the wet season and through the groundwater pathway in the dry season.
JOURNAL OF HYDROLOGY
(2023)
Article
Environmental Sciences
Weilun Gao, Zheng Bing Wang, Maarten G. Kleinhans, Chiyuan Miao, Baoshan Cui, Dongdong Shao
Summary: A river bifurcation plays a critical role in distributing water, sediment, and nutrients to the downstream branches of deltaic river networks. However, the effects of a connecting channel between the downstream branches on water partitioning and hydrological connectivity are still not well understood.
WATER RESOURCES RESEARCH
(2023)
Article
Environmental Sciences
Zihan Zhao, Mingli Zhang, Yan Chen, Chaopu Ti, Jiaming Tian, Xinghua He, Kangkang Yu, Wangyue Zhu, Xiaoyuan Yan, Yanhua Wang
Summary: The adverse effects of increased nitrate pollution, primarily from non-point sources, on the hydrosphere and anthroposphere are becoming more prominent. This study used dual-stable isotopes to identify the sources of nitrate in a mixed agricultural and urban region in the Yangze River delta. The results showed that manure and sewage were the main contributors to nitrate pollution, followed by soil leachate and chemical fertilizer. Highly urbanized and hybrid areas were identified as hotspot areas with heavy nitrate pollution. Changes in wastewater treatment, agricultural production structure, and meteorological factors were found to influence nitrate concentration and sources in the upstream Taihu Lake Basin.
ENVIRONMENTAL POLLUTION
(2022)
Article
Green & Sustainable Science & Technology
Yuan Cui, Ying-Hu Zhang, Shi-Jun Zhou, Yue-Yan Pan, Rui-Qing Wang, Zhen Li, Zhen Ming Zhang, Ming -Xiang Zhang
Summary: This study reveals the role of static and dynamic connectivity in vertical hydrological connectivity in soil. Static connectivity is mainly formed by cracks and root channels in the soil, leading to heterogeneous distribution of water and solutes. Dynamic connectivity differs between soil columns, with non-equilibrium flow characterized by high infiltration rate and concentration. Static connectivity has a significant impact on water movement, but no effect on solute transport.
JOURNAL OF CLEANER PRODUCTION
(2022)
Article
Ecology
Yinghu Zhang, Jiang Jiang, Jinchi Zhang, Zhenming Zhang, Mingxiang Zhang
Summary: In this study, a new method using field dye-tracing experiments was utilized to assess hydrological connectivity below the soil surface, showing a non-linear decrease in the index of hydrological connectivity (IHC) with depth. The roots systems of Phragmites australis were found to be mainly distributed in soils of 0-30 cm and were positively correlated with IHC. Coarse roots systems significantly contributed to changes in IHC.
Article
Environmental Sciences
Yanan Wu, Yinghu Zhang, Liyi Dai, Lumeng Xie, Shiqiang Zhao, Ying Liu, Zhenming Zhang
Summary: This study found that hydrological connectivity significantly influences soil nutrients and root architecture parameters, with higher connectivity leading to higher soil nutrients and root structures. In wetland protection and restoration efforts, attention should be paid to both watershed-scale and smaller-scale hydrological connectivity.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Review
Environmental Sciences
Carlos Garcia de Leaniz, Jesse R. O'Hanley
Summary: Barrier removal is an effective method for restoring river connectivity, but resources for defragmenting rivers are limited, requiring a prioritization strategy. The effectiveness of barrier removal depends on barrier typology, location, size, and impacts, with a focus on targeting barriers with high fragmentation impacts. Prioritization methods can be reactive or proactive, local or larger-scale, and formal or informal, with a hybrid approach likely to be the most effective. Accuracy in stream networks, barrier coordinates, and numbers is crucial for successful barrier removal projects, with ground truthing and predictive modeling as potential solutions for uncertainties.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Geosciences, Multidisciplinary
Alex Miltenberger, Tapan Mukerji, Jayaram Hariharan, Paola Passalacqua, Erik Nesvold
Summary: This study proposes a probabilistic framework based on Monte Carlo and metrics to test the ability of numerical delta models in capturing the link between surface dynamics and subsurface structures. The results show that certain delta surface features are informative of the spatial organization of sediment in the subsurface, while others are less informative. Key differences between experimental and numerical surface dynamics are likely due to limitations in numerical model resolution and assumptions in the model physics.
MATHEMATICAL GEOSCIENCES
(2022)
Article
Geography, Physical
Matthew Hiatt, Elisabeth A. Addink, Maarten G. Kleinhans
Summary: This article uses graph theory to quantify the connectivity of multidirectional estuarine channel networks, finding higher levels of structural connectivity in larger networks with looping structures. Real-world networks contain signatures of both mutually evasive flood and ebb channels, as well as branching structures, with flow direction influencing dynamical connectivity.
EARTH SURFACE PROCESSES AND LANDFORMS
(2022)
Article
Geography, Physical
Willem Sonke, Maarten G. Kleinhans, Bettina Speckmann, Wout M. van Dijk, Matthew Hiatt
Summary: Channels in rivers and estuaries play a critical role in sediment transport. The study compares two mathematically rigorous methods for identifying channel networks and concludes that the local method is more conceptually effective and stable. Additionally, the concept of alluvial connectivity between channels is closely related to the displacement of sediment volume.
EARTH SURFACE PROCESSES AND LANDFORMS
(2022)
Article
Marine & Freshwater Biology
Andre S. Rovai, Robert R. Twilley, Alexandra Christensen, Annabeth McCall, Daniel J. Jensen, Gregg A. Snedden, James T. Morris, John A. Cavell
Summary: The study reveals that Colocasia esculenta, a species of tidal freshwater marsh, is able to cope with longer hydroperiods caused by river sediment diversions, and even increase its biomass. This is in contrast to previous studies conducted in brackish and saline settings where longer hydroperiods had negative effects on biomass accumulation.
ESTUARINE COASTAL AND SHELF SCIENCE
(2022)
Article
Geography, Physical
Azure E. Bevington, Robert R. Twilley, Charles E. Sasser
Summary: This study analyzed herbaceous wetland vegetation species percent cover data collected over five growing seasons (2007-2011) to examine the unique species assemblages along the elevation gradient of deltaic islands in Wax Lake Delta. The research found two significant persistent species assemblages, with hurricanes and major river floods significantly affecting lower elevation plant species' aboveground cover.
Article
Engineering, Environmental
Xing Zheng, Claudia D'Angelo, David R. Maidment, Paola Passalacqua
Summary: Flood modeling provides inundation estimates for disaster preparedness and response. This study presents an application of a flood mapping system and validates its outputs using high-water marks. The results show that the mapping system estimates water depth with a mean error of 0.5 m and covers over 90% of the inundation extent derived from high-water marks.
JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION
(2022)
Article
Environmental Sciences
Nelson Tull, Paola Passalacqua, Hima J. Hassenruck-Gudipati, Shazzadur Rahman, Kyle Wright, Jayaram Hariharan, David Mohrig
Summary: Hydrologic connectivity plays a critical role in the lateral exchange between rivers and floodplains. This study investigates the impact of heavy rainfall on floodplain hydrodynamics, using data collected during Tropical Storm Imelda in the Trinity River floodplain. The study reveals that rainfall initiates lateral exchange before river discharge reaches flood levels, and rainwater generally remains in the floodplain for a longer time than river water after the rain stops. The study emphasizes the complexity of floodplain hydrodynamics under heavy rainfall conditions and its implications for sediment deposition and nutrient transport.
WATER RESOURCES RESEARCH
(2022)
Article
Geosciences, Multidisciplinary
Kyle Wright, Jayaram Hariharan, Paola Passalacqua, Gerard Salter, Michael P. Lamb
Summary: Understanding the partitioning of fluvially transported materials in river deltas is crucial for predicting their morphological changes and the fate of environmental constituents and contaminants. However, translating water-based partitioning estimates into fluxes of nonwater materials can be challenging due to uneven distribution and characteristic transport pathways. In this study, a novel reduced-complexity modeling approach is presented to simulate patterns of transport of suspended fluvial inputs influenced by vertical stratification and topographic steering.
JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE
(2022)
Article
Geosciences, Multidisciplinary
Carmine Donatelli, Paola Passalacqua, Kyle Wright, Gerard Salter, Michael P. Lamb, Daniel Jensen, Sergio Fagherazzi
Summary: Deltas are threatened by sea-level rise, sediment starvation, and subsidence. Remote sensing can be used to estimate flow velocities in deltas by leveraging the synoptic information offered by the technology. This approach provides a more comprehensive understanding of the spatiotemporal variability in flow velocity, which is crucial for forecasting the fate of these fragile ecosystems.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Geosciences, Multidisciplinary
Zhongyuan Xu, Mahfuzur R. Khan, Kazi Matin Ahmed, Anwar Zahid, Jayaram Hariharan, Paola Passalacqua, Elisabeth Steel, Austin Chadwick, Chris Paola, Steven L. L. Goodbred Jr, Anner Paldor, Holly A. Michael
Summary: Groundwater is the primary water source in the Bengal Delta, but it is under threat from contamination. By using surface information to model subsurface features, the predictions of groundwater flow can be improved. The land surface features in active deltas play a significant role in evaluating groundwater vulnerability to contamination.
JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE
(2023)
Article
Green & Sustainable Science & Technology
Douglas A. A. Edmonds, Stephan C. C. Toby, Christopher G. G. Siverd, Robert Twilley, Samuel J. J. Bentley, Scott Hagen, Kehui Xu
Summary: Land loss in the Mississippi River Delta is caused by human activities that alter sediment budget, including dam building, levee construction, and subsurface resource extraction. A numerical model analysis reveals that the installation of flood-protection levees and the extraction of subsurface resources have been the primary drivers of land loss in the Barataria Basin within the delta. Additionally, the impact of dams on sediment supply reduction may not be as detrimental to sediment diversions and coastal restoration as previously thought.
NATURE SUSTAINABILITY
(2023)
Article
Marine & Freshwater Biology
Callie Snow, Sibel Bargu, Courtney Nicole Hammond, Matthew Hiatt, John R. R. White
Summary: Globally, estuaries are experiencing hydrological changes due to climate change and flood management, resulting in increased harmful algal blooms (HABs). In coastal Louisiana, the introduction of nutrient-rich Mississippi River water into Lake Pontchartrain Estuary leads to toxic cyanobacterial blooms (CyanoHABs). This study examines the impact of the river input on biological measures of the water column and provides insights into predicting the response of estuaries to nutrient-loading events.
Article
Chemistry, Analytical
Selena Chavez, Shimon Wdowinski, David Lagomasino, Edward Castaneda-Moya, Temilola Fatoyinbo, Ryan P. P. Moyer, Joseph M. M. Smoak
Summary: In September 2017, Hurricane Irma caused significant damage to the mangrove forests in South Florida, resulting in canopy defoliation, broken branches, and downed trees. Using lidar remote sensing and field data, this study assessed the damage and changes in mangrove forests from Hurricane Irma. The results showed a regional scale loss of aboveground necromass (standing dead trees) of 29% and significant damage in the Shark River area compared to other areas impacted by the hurricane or previous disturbances in the region.
Article
Geosciences, Multidisciplinary
Carmine Donatelli, Paola Passalacqua, Daniel Jensen, Talib Oliver-Cabrera, Cathleen E. Jones, Sergio Fagherazzi
Summary: Water movement in coastal wetlands is influenced by topography, vegetation characteristics, and hydrological processes. This study utilizes remote sensing data to analyze water-level changes and vegetation contributions in marshes, revealing the importance of small geomorphic features and the minor role of vegetation in water retention.
JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE
(2023)
Article
Water Resources
Matthew Preisser, Paola Passalacqua, R. Patrick Bixler, Stephen Boyles
Summary: Government and non-governmental agencies are making efforts to quantify the disproportionate effects of climate risk on vulnerable populations and create more resilient communities. This study addresses the limitation of using sociodemographic based indices to measure vulnerability and proposes a model based on open-source data to assess individuals' access to critical resources during and after a flood event. The results show that the most vulnerable households are the least resilient and experience the largest shifts in metric values, while the least vulnerable quarter of the population carries the smallest burdens. The model developed can assist emergency planning stakeholders in identifying households that require specific resources in real-time.
FRONTIERS IN WATER
(2023)
