Article
Engineering, Civil
Jing Zhang, Junfeng Gao, Qing Zhu, Rui Qian, Qimou Zhang, Jiacong Huang
Summary: This study successfully characterized nitrogen (N) and phosphorus (P) loading in a mountain-lowland mixed watershed system by coupling different models. The investigation revealed that three watersheds (Nanfei, Pai and Baishitian River Watersheds) contributed significantly to N and P loading in Lake Chaohu Basin. Additionally, polders in the basin exhibited higher N and P retention capacity compared to mountain watersheds. Population density, precipitation intensity, and soil erosion were identified as critical drivers of N and P loss.
JOURNAL OF HYDROLOGY
(2022)
Article
Environmental Sciences
Rebecca M. Kreiling, Patrik M. Perner, Kenna J. Breckner, Tanja N. Williamson, Lynn A. Bartsch, James M. Hood, Nathan F. Manning, Laura T. Johnson
Summary: Reducing phosphorus (P) concentrations in aquatic ecosystems is crucial for improving water quality and preventing harmful algal blooms. This study focused on the Maumee River network, a major source of P loads to Lake Erie, to understand the role of rivers in P transport. The researchers found that stream sediment acted as a P sink at most sites, but could become a P source if stream water SRP concentrations decrease. Factors such as agricultural land use and stream size influenced the concentrations of SRP and sediment P saturation, which in turn affected the spatial variation in the zero equilibrium P concentration (EPC0).
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Environmental Sciences
Sandra Poikane, Martyn G. Kelly, Gabor Varbiro, Gabor Borics, Tibor Eros, Seppo Hellsten, Agnieszka Kolada, Balazs Andras Lukacs, Anne Lyche Solheim, Jose Pahissa Lopez, Nigel J. Willby, Georg Wolfram, Geoff Phillips
Summary: This study provides ecology-based nutrient targets for five major ecoregions in Europe and reveals strong relationships between phosphorus and phytoplankton. However, the relationships between nutrient and biological communities are weak or non-significant in the very shallow lakes of the Eastern Continental region. Additionally, fish stocking negatively affects the ecological status of Eastern Continental lakes.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Environmental Sciences
Nolan J. T. - Pearce, James H. Larson, Mary Anne Evans, Paul C. Frost, Marguerite A. Xenopoulos
Summary: The study shows that rivermouths can effectively process nutrients bound for downstream ecosystems and respond to episodic nutrient enrichment. Light incubations exhibit higher nutrient uptake rates, with nutrient enrichment leading to increased uptake of total dissolved P and total dissolved N, as well as increased DOC release.
JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES
(2021)
Article
Environmental Sciences
James H. Larson, Mary A. Evans, Faith A. Fitzpatrick, Paul C. Frost, Marguerite A. Xenopoulos, William F. James, Paul C. Reneau
Summary: The interface between lotic and lentic ecosystems is a zone of intense metabolic activity, where rivermouths can significantly alter the load and character of nutrients passing from the tributary to nearshore areas. Sensitivity analysis of the model showed that water column processing rates become more important with increasing nutrient concentration and discharge. Simulations at the Fox rivermouth indicated that it serves as a net sink for SRP and a source for ammonia, with water column processing driving SRP removal and both water column and sediment flux driving NH4 dynamics.
Article
Environmental Sciences
Tetsuro Kikuchi, Toshihiko Anzai, Takao Ouchi, Ken Okamoto, Yoshifumi Terajima
Summary: Excessive loadings of nitrogen and phosphorus, combined with imbalances in silicon, have a detrimental effect on water quality and ecosystems in receiving waters. This study conducted periodic water quality monitoring in rivers and streams on Ishigaki Island, Japan, to identify the factors influencing the concentrations of dissolved inorganic nitrogen (DIN), total phosphorus (TP), and dissolved silicon (DSi), with a focus on catchment characteristics. Using a machine learning algorithm called Random Forest (RF), predictive models were developed to estimate nutrient concentrations based on catchment properties. The results showed that agricultural land use significantly influenced DIN and TP concentrations, while broadleaf forests were the most important factor for DSi. Additionally, the study estimated the contributions of DIN from sugarcane fields and livestock barns to riverine DIN, which accounted for up to 60% of the total in the studied river basins. The findings also indicated that DIN from sugarcane fields is more likely to leach into groundwater and rivers in catchments dominated by calcareous geology. These results and methodology have implications for water quality assessment and management in both inland and coastal waters.
ENVIRONMENTAL POLLUTION
(2023)
Article
Environmental Sciences
Ethan D. Pawlowski, Diana L. Karwan, Randall K. Kolka
Summary: This study uses a user-friendly field-scale tool to model nutrient and sediment export reductions in the Fox River Watershed, Wisconsin, USA. The results show that targeted vegetation implementation can significantly reduce nutrient and sediment exports from agricultural areas. However, further parameter adjustments are needed to improve the accuracy of the model.
JOURNAL OF SOILS AND SEDIMENTS
(2023)
Article
Environmental Sciences
Sarah Stackpoole, Robert Sabo, James Falcone, Lori Sprague
Summary: This study quantified annual changes in nitrogen and phosphorus river loads and nutrient balances at the Mississippi River outlet. It was found that the river load response to watershed nutrient balances shifted between 1975 and 2017. The impacts of legacy nutrients and other latent factors on river nutrient load trends were evaluated, showing the potential importance of factors such as best management practices and changes in watershed buffering capacity.
WATER RESOURCES RESEARCH
(2021)
Article
Engineering, Environmental
Dongyang Ren, Bernard Engel, Johann Alexander Vera Mercado, Tian Guo, Yaoze Liu, Guanhua Huang
Summary: Identifying key processes and sources of water and nutrient losses is crucial in watershed management. This study used the SWAT model to simulate water and nutrient balance in an agricultural watershed in the U.S. Corn Belt. The results showed that the corn-soybean rotation system was the main contributor to nitrogen and phosphorus inputs and losses, and the non-growing season was identified as the critical period for water and nutrient losses.
Article
Ecology
Ted Ozersky, Andrew Camilleri
Summary: Research found that the growth of periphyton in lakes is mainly limited by primary N or N + P co-limitation, with more severe nutrient limitations in eutrophic lakes, supporting the different responses of phytoplankton and periphyton to nutrient enrichment. Additionally, periphyton can serve as an early warning indicator of nutrient pollution, and oligotrophic lakes are more susceptible to localized benthic algal blooms.
FRESHWATER BIOLOGY
(2021)
Article
Environmental Sciences
Lorrayne Miralha, Rebecca L. Muenich, Donald Scavia, Karlie Wells, Allison L. Steiner, Margaret Kalcic, Anna Apostel, Samantha Basile, Christine J. Kirchhoff
Summary: This study compares different bias correction methods on nutrient loads and hydrological processes in waterbodies, showing that the choice of method significantly impacts predictions. In a changing climate scenario, nutrient loads in the Maumee basin are expected to decrease.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Environmental Sciences
F. S. Pacheco, J. P. H. B. Ometto, L. Gomes, K. Tosto, M. Miranda, S. Loverde-Oliveira, D. D. Pessi, C. Cox
Summary: The study found that phosphorus balance in cropping systems in the Vermelho River watershed in Upper Pantanal, Brazil, is positive, while in grazing systems it tends to be negative. The positive balance in cropping systems is mainly due to high phosphorus inputs from mineral fertilizers and high soil phosphorus sorbing capacities, while the negative balance in grazing systems is a result of nutrient removal without replenishment.
JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES
(2021)
Editorial Material
Multidisciplinary Sciences
Boqiang Qin, Yunlin Zhang, Jianming Deng, Guangwei Zhu, Jianguo Liu, David P. Hamilton, Hans W. Paerl, Justin D. Brookes, Tingfeng Wu, Kai Peng, Yizhou Yao, Kan Ding, Xiaoyan Ji
Summary: China has successfully improved the water quality of rivers, but lakes still face challenges in terms of water quality. Achieving the United Nations Sustainable Development Goals requires controlling external nutrient loads and internal loads in lakes, utilizing a combination of nature-based solutions and engineered systems.
NATIONAL SCIENCE REVIEW
(2022)
Article
Environmental Sciences
Xiaomei Su, Alan D. Steinman, Yunlin Zhang, Hong Ling, Dan Wu
Summary: Hydraulic disturbance in shallow lakes can lead to the release of sediment nutrients into the water column, contributing to nutrient enrichment and eutrophication. This study examined the seasonal variations and spatial distributions of nitrogen and phosphorus in Lake Yangcheng and its tributaries. The concentrations of nutrients were higher in the connected rivers compared to the lake, indicating external loading as a significant contributor. The study also found that nutrient concentrations varied temporally and spatially, with highest values observed in the winter for TN and in the summer for TP. The enrichment of nutrients in the lake sediment was severe, calling for further research on the seasonality of nutrient exchange.
Article
Environmental Sciences
Katarzyna Kowalczewska-Madura, Renata Dondajewska-Pielka, Ryszard Goldyn
Summary: The successful management of lake ecosystems used for recreation depends on identifying nutrient sources and implementing appropriate measures. This study analyzed external and internal nutrient loading in the hypereutrophic Raczynskie Lake, finding distinct seasonal variability in both sources. To improve water quality, it is essential to divert stormwater runoff, reduce nutrient content in tributaries, and implement restoration treatments for phosphorus inactivation and reduction.
Article
Environmental Sciences
Michael T. O'Connor, M. Bayani Cardenas, Bethany T. Neilson, Kindra D. Nicholaides, George W. Kling
WATER RESOURCES RESEARCH
(2019)
Article
Geosciences, Multidisciplinary
Michael T. O'Connor, M. Bayani Cardenas, Stephen B. Ferencz, Yue Wu, Bethany T. Neilson, Jingyi Chen, George W. Kling
GEOPHYSICAL RESEARCH LETTERS
(2020)
Article
Microbiology
Sarah G. Nalven, Collin P. Ward, Jerome P. Payet, Rose M. Cory, George W. Kling, Thomas J. Sharpton, Christopher M. Sullivan, Byron C. Crump
ENVIRONMENTAL MICROBIOLOGY
(2020)
Article
Geosciences, Multidisciplinary
J. C. Bowen, C. P. Ward, G. W. Kling, R. M. Cory
GEOPHYSICAL RESEARCH LETTERS
(2020)
Article
Ecology
Edward B. Rastetter, George W. Kling, Gaius R. Shaver, Byron C. Crump, Laura Gough, Kevin L. Griffin
Summary: This study presents a framework for assessing the biogeochemical recovery of terrestrial ecosystems from disturbances, outlining three recovery phases. The level of openness of the nitrogen cycle, nitrogen distribution in vegetation and soils, and the proportion of nitrogen losses in a refractory form all play key roles in influencing recovery trajectories. High openness exacerbates initial nitrogen losses but accelerates later recovery phases, while a high fraction of ecosystem nitrogen in vegetation can have a similar effect. Additionally, a high proportion of nitrogen loss in a refractory form mitigates initial nitrogen losses and speeds up recovery in later phases.
Article
Limnology
Phaedra Budy, Casey A. Pennock, Anne E. Giblin, Chris Luecke, Daniel L. White, George W. Kling
Summary: The study found that climate change-driven disturbances in lakes can lead to increased nutrient loading, affecting ecosystem function. A fertilization experiment showed varying responses in phytoplankton chlorophyll a, dissolved oxygen, and zooplankton biomass during the fertilization period, with delayed declines in water transparency and fish abundance. This suggests that indirect effects of climate change altering nutrient inputs may impact many lakes in the future.
LIMNOLOGY AND OCEANOGRAPHY
(2022)
Article
Biotechnology & Applied Microbiology
Derek J. Smith, Michelle A. Berry, Rose M. Cory, Thomas H. Johengen, George W. Kling, Timothy W. Davis, Gregory J. Dick
Summary: Cyanobacterial harmful algal blooms (CHABs) pose a global threat to freshwater ecosystems due to toxin production. This study reveals the key role of heterotrophic bacteria in decomposing hydrogen peroxide (H2O2) and suggests their activity may impact the fitness and strain composition of CHABs. The dichotomy of toxin-producing and non-toxin-producing strains may not drive the succession of toxin-producing species.
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
(2022)
Article
Microbiology
Karl J. Romanowicz, George W. Kling
Summary: Climate warming has increased permafrost thaw and extended thaw duration in arctic tundra, affecting the composition of soil microbiome. Thaw duration has a greater impact on microbial taxa composition than thaw frequency.
ENVIRONMENTAL MICROBIOLOGY
(2022)
Article
Environmental Sciences
Werner Eugster, Tonya DelSontro, James A. Laundre, Jason Dobkowski, Gaius R. Shaver, George W. Kling
Summary: Methane and carbon dioxide effluxes from aquatic systems in the Arctic will affect and likely amplify global change. This study aims to measure the release of carbon to the atmosphere via effluxes of methane and carbon dioxide from Toolik Lake in northern Alaska. The results show that the measured flux values were higher than predicted, with the surrounding tundra vegetation and topography playing a significant role in increasing atmospheric turbulence. The study also highlights the importance of biological processing of dissolved organic carbon in understanding future trends in aquatic gas fluxes.
FRONTIERS IN ENVIRONMENTAL SCIENCE
(2022)
Article
Biodiversity Conservation
Edward B. Rastetter, Kevin L. Griffin, Bonnie L. Kwiatkowski, George W. Kling
Summary: This study examines the impacts of changes in day-to-day weather variability on ecosystem function. The results show that weather variability alters ecosystem carbon, nitrogen, and phosphorus stocks and cycling rates. However, the responses of individual ecological processes to weather variability are inconsistent due to ecosystem feedbacks. This study highlights the importance of weather variability for ecosystem responses.
GLOBAL CHANGE BIOLOGY
(2023)
Article
Soil Science
Karl J. Romanowicz, Byron C. Crump, George W. Kling
Summary: The research findings show that rainfall can increase soil oxygen concentration, but different tundra types have varying responses to rainfall. In tussock tundra, there is a 2.5-fold increase in soil oxygen concentration compared to wet sedge tundra, due to differences in soil drainage. Microbial communities also exhibit divergent responses to rainfall, with tussock tundra microbial community showing a decline in gene expression for anaerobic metabolism and an increase in gene expression for cellular growth, while wet sedge tundra microbial community does not show significant changes in gene expression.
Proceedings Paper
Computer Science, Artificial Intelligence
Yue Wu, Jingyi Chen, Michael O'Connor, Stephen B. Ferencz, George W. Kling, M. Bayani Cardenas
IGARSS 2020 - 2020 IEEE INTERNATIONAL GEOSCIENCE AND REMOTE SENSING SYMPOSIUM
(2020)
Article
Chemistry, Analytical
Werner Eugster, Tonya DelSontro, Gaius R. Shaver, George W. Kling
ENVIRONMENTAL SCIENCE-PROCESSES & IMPACTS
(2020)
Article
Meteorology & Atmospheric Sciences
Werner Eugster, James Laundre, Jon Eugster, George W. Kling
ATMOSPHERIC MEASUREMENT TECHNIQUES
(2020)
Article
Soil Science
Adrianna Trusiak, Lija A. Treibergs, George W. Kling, Rose M. Cory
