Article
Biodiversity Conservation
Jianfeng Chen, Qingchuan Chou, Wenjing Ren, Haojie Su, Meng Zhang, Te Cao, Tianshun Zhu, Leyi Ni, Zugen Liu, Ping Xie
Summary: Decreased underwater light availability is an important environmental factor leading to the decline in submersed macrophytes in lakes. This study investigated the growth, morphology, and C/N metabolism of Vallisneria natans under different light conditions. The results showed that light intensity had a significant impact on the biomass and morphology of V. natans, with leaves being the most sensitive to light availability. The study also provided useful information for lake V. natans restoration and seedling cultivation in limited-resource environments.
ECOLOGICAL INDICATORS
(2022)
Article
Environmental Sciences
Meredith E. Theus, Nicholas E. Ray, Sheel Bansal, Meredith A. Holgerson
Summary: Shallow freshwater ecosystems emit large amounts of greenhouse gases, but the emissions are highly variable. The role of aquatic macrophytes in regulating greenhouse gas emissions is uncertain. This study found that high density of submersed macrophytes results in higher concentrations and emissions of carbon dioxide and methane, while lower and medium densities have no significant difference in methane concentration. The high density treatment also showed a loss of biomass, indicating die-off and addition of organic matter to the sediment. High organic matter loading and low dissolved oxygen likely stimulated greenhouse gas production in the high density treatment.
JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES
(2023)
Article
Environmental Sciences
Meredith E. Theus, Nicholas E. Ray, Sheel Bansal, Meredith A. Holgerson
Summary: The density and growth cycle of submersed macrophytes play a crucial role in regulating greenhouse gas emissions in shallow freshwater ecosystems. High density macrophytes increase the concentration and emissions of CO2 and CH4, resulting in increased greenhouse gas production due to high organic matter loading and low dissolved oxygen.
JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES
(2023)
Article
Environmental Sciences
Ye-Xin Yu, Yan Li, Hai-Jun Wang, Xiao-Dong Wu, Miao Zhang, Hong-Zhu Wang, David P. Hamilton, Erik Jeppesen
Summary: The study showed that enhancing underwater light conditions using LED lights can help restore the growth of submersed macrophytes in urban lakes, especially in eutrophic conditions. Plants in the high light treatment had significantly higher leaf number, maximum leaf length, and average leaf length. Periphyton chlorophyll a increased significantly with plant growth variables and was higher in the light treatments, but did not hinder the growth of the macrophytes.
ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
(2021)
Article
Biochemistry & Molecular Biology
Gaojie Li, Yan Chen, Xuyao Zhao, Jingjing Yang, Xiaoyu Wang, Xiaozhe Li, Shiqi Hu, Hongwei Hou
Summary: In this study, the GRF gene family in aquatic species was comprehensively analyzed. A total of 130 GRF genes were identified in 13 aquatic plants, and the gene structures, motifs, and regulatory elements were further analyzed. The results provide a foundation for understanding the functions of these genes.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Engineering, Environmental
Haifeng Yan, Zaisheng Yan, Luming Wang, Zheng Hao, Juan Huang
Summary: Rhizodegradation using the submersed macrophytes Vallisneria natans shows potential for restoring polycyclic aromatic hydrocarbon (PAH)-contaminated sediments. This study found that different sediment types can influence the outcomes of rhizoremediation and the microbial communities along the sediment-V. natans continuum. V. natans presence was particularly effective in highly contaminated sites, influencing PAH rhizodegradation and microbial communities, especially in rhizosphere sediments. The microbial community structure along the sediment-plant continuum was primarily shaped by the niche of V. natans. Selective enrichment of specific microbial taxa like Herbaspirillum was observed in the endosphere of V. natans, which can use PAH as a carbon source and promote plant growth. Understanding the interactions between V. natans and microbes could help develop novel decontamination strategies based on rhizosphere and root interior interactions between plants and their microbial associates.
JOURNAL OF HAZARDOUS MATERIALS
(2022)
Article
Engineering, Chemical
Chengxiang Zhang, Hongcui Pei, Cai Lu, Peizhong Liu, Cunqi Liu, Guangchun Lei
Summary: The homeostasis for phosphorus in submerged macrophytes affects the susceptibility of lakes to regime shifts. High-phosphorus macrophytes have a relative growth advantage and a stronger phytoplankton inhibition capacity during eutrophication. The transition from high-HP species-dominance to low-HP species-dominance erodes the phytoplankton inhibition capacity and promotes the shift from a clear-water state to a turbid state.
Article
Environmental Sciences
Guixiang Yuan, Zhenzhi Yang, Lijun Sun, Hui Fu, Hui Peng, Erik Jeppesen
Summary: This study investigated the reproduction and growth of Vallisneria spinulosa under different light intensities. The results showed that asexual reproduction was more important for population maintenance, and it had a low light requirement. Under high light, plants had higher biomass and tuber biomass, and tended to form more small-sized tubers. Small-sized tubers had high nitrogen content and early germination, supporting the fast establishment of V. spinulosa populations in spring.
Article
Engineering, Environmental
Qi Zhang, Yuchen Chen, Min Wang, Jianyun Zhang, Qiuwen Chen, Dongsheng Liu
Summary: The study investigated the molecular responses of algal growth and toxin formation under different phosphorus sources, with high-concentration dissolved inorganic phosphorus promoting the growth of Microcystis aeruginosa, while high-concentration dissolved organic phosphorus triggered the release of intracellular microcystins.
Article
Environmental Sciences
Chengxiang Zhang, Hongcui Pei, Cai Lu, Cunqi Liu, Wei Wang, Xiaobo Zhang, Peizhong Liu, Guangchun Lei
Summary: This study investigates the effects of temporary grass carp and scraping snail introductions on submerged macrophytes and the impacts of herbivores on underwater light conditions, aiming to halt the regime shift from clear to turbid in shallow lakes.
ENVIRONMENTAL POLLUTION
(2022)
Article
Environmental Sciences
Lu Wang, Tingting Yang, Pengfei Hei, Jing Zhang, Jing Yang, Te Luo, Gang Zhou, Chunlan Liu, Ranran Wang, Feng Chen
Summary: In macrophyte-dominated eutrophication (MDE) lakes, the cycling of phosphorus (P) predominantly occurs through macrophyte sediment, challenging the current strategies for lake eutrophication management. This study suggests that successful restoration of MDE lakes should focus on stressors caused by sustainable macrophyte-sediment P cycling. The technique of macrophyte harvesting before withering is recommended as the most sustainable method for managing periodically frozen shallow MDE lakes.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2022)
Article
Environmental Sciences
Willem Kaijser, Armin W. Lorenz, Sebastian Birk, Daniel Hering
Summary: This study presents a conceptual model on the interaction between algae, macrophytes, DIC, pH, light, N, P, and the surface water and sedimental compartment in rivers. Data analysis quantifies three connections within this concept, showing the importance of factors such as pH, chlorophyll-a, and the utilization of HCO3- by macrophytes along the DIC gradient. The results emphasize the significant impact of DIC on riverine macrophytes and suggest that river monitoring and management should consider the interaction between nutrients DIC, surface water, and sedimental compartment as important factors affecting macrophyte occurrence.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Plant Sciences
Asif Iqbal, Dong Qiang, Xiangru Wang, Huiping Gui, Hengheng Zhang, Xiling Zhang, Meizhen Song
Summary: We investigated the performance of two cotton genotypes with different phosphorus tolerance under low and normal phosphorus conditions. The results showed that the strong low phosphorus tolerance in Jimian169 is linked with better root system and enhanced phosphorus and carbohydrate metabolism, making it a model genotype for cotton breeding.
Article
Environmental Sciences
Lara M. Schuijt, Tamara J. H. M. van Bergen, Leon P. M. Lamers, Alfons J. P. Smolders, Piet F. M. Verdonschot
Summary: This study demonstrated the potential of applying ecological principles in waste recovery and biomass production in wastewater treatment, utilizing positive species interactions between aquatic plants and worms. The use of a biocascade significantly increased biomass production of Azolla filiculoides and reduced waste sludge through interspecific facilitation processes.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Environmental Sciences
K. Benjamin Woodward, Deborah Hofstra
Summary: The presence of oxygen in lake sediments reduces sediment oxygen demand, improves sediment phosphorus retention and coupled nitrification/denitrification. However, the release of oxygen from the roots of macrophytes has not been previously measured in highly reducing sediments. In this study, the oxygen release from the roots of Isoetes kirkii in lake sediments was found to be higher due to the higher sediment oxygen demand, potentially pushing the plants close to their survival limit.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Fisheries
Arianto B. Santoso, David P. Hamilton, Louis A. Schipper, Ilia S. Ostrovsky, Chris H. Hendy
Summary: This study identified the processes affecting CO2 and CH4 concentrations in Lake Okaro, New Zealand, and found that the lake acted as a sink for atmospheric CO2 and a source for CH4, resulting in a net GHG emission. Although conservative and only applying to diffusive fluxes, the study suggests that eutrophic lakes with high primary production rates may be net sources of GHGs.
NEW ZEALAND JOURNAL OF MARINE AND FRESHWATER RESEARCH
(2021)
Review
Environmental Sciences
Jonathan M. Abell, Deniz Ozkundakci, David P. Hamilton, Paula Reeves
Summary: This review examines approaches used in addressing eutrophication in shallow lakes and evaluates a set of case studies. It finds that reducing external nutrient loads is a crucial component of successful restoration, although supplementary measures can also support restoration goals. However, restoring shallow lakes faces various challenges, including insufficient reductions in external nutrient loads, biogeochemical lags, resistance to change in stable algal-dominated states, delayed macrophyte reestablishment, climate change, lake-specific approaches, and social and political obstacles.
CRITICAL REVIEWS IN ENVIRONMENTAL SCIENCE AND TECHNOLOGY
(2022)
Article
Environmental Sciences
Chiara Pasut, Fiona H. M. Tang, David P. Hamilton, Federico Maggi
Summary: Australian ecosystems, particularly wetlands, are facing significant threats from climate change, land use, and human interventions. The study found that temperate wetlands in Australia have three times more N2O emissions than tropical wetlands. Nutrient fluxes in soil are mainly governed by plant uptake, while C fluxes depend strongly on hydroclimatic factors.
Article
Environmental Sciences
Chiara Pasut, Fiona H. M. Tang, David Hamilton, William J. Riley, Federico Maggi
Summary: Wetlands play a critical role in regulating global greenhouse gas emissions, but are impacted by anthropogenic factors like agricultural runoff. A model was used to estimate GHG emissions and nutrient sequestration rates in wetlands, with key controls found to be temperature, net primary productivity, and methanogenic microorganisms.
GLOBAL BIOGEOCHEMICAL CYCLES
(2021)
Article
Microbiology
Chuang Li, K. David Hambright, Hannah G. Bowen, Majoi A. Trammell, Hans-Peter Grossart, Michele A. Burford, David P. Hamilton, Helong Jiang, Delphine Latour, Elisabeth Meyer, Judit Padisak, Richard M. Zamor, Lee R. Krumholz
Summary: Global warming and eutrophication are leading to an increase in cyanobacterial blooms worldwide, with cyanobacterial biomass strongly linked to methane emissions from lakes. Methanogens, mainly Methanoregula and Methanosaeta, were detected in half of the lakes, while certain lakes contained more abundant methanotrophs, such as Methyloparacoccus, Crenothrix, and an uncultured Methylobacter species, which were closely associated with the presence of methanogens.
ENVIRONMENTAL MICROBIOLOGY
(2021)
Article
Limnology
Bryan M. Spears, David P. Hamilton, Yang Pan, Chu Zhaosheng, Linda May
Summary: This study emphasizes that taking early actions to prevent degradation of lakes is preferable to attempting to restore already degraded lakes in order to maintain the continuity of ecosystem services. Comparing case studies shows that preventative approaches help mitigate the impacts of human pressures, and protect or enhance long-term societal benefits.
Editorial Material
Limnology
Bryan M. Spears, Miquel Lurling, David P. Hamilton
Review
Geography, Physical
Melanie E. Roberts, Ryan M. Burrows, Robin N. Thwaites, David P. Hamilton
Summary: This review synthesizes contemporary models for classical gully erosion and identifies nine opportunities for the development of gully erosion models.
Article
Engineering, Environmental
Mohammad Hassan Ranjbar, David P. Hamilton, Amir Etemad-Shahidi, Fernanda Helfer
Summary: This study investigates the impact of atmospheric stilling on the distribution of Microcystis blooms. The results highlight the importance of considering dynamic variations in colony size for accurate prediction of cyanobacterial bloom development and decay. The findings suggest that atmospheric stilling needs to be included in projections of changes in the frequency, distribution and magnitude of blooms of buoyant, colony-forming cyanobacteria under climate change.
Article
Environmental Sciences
Gebiaw T. Ayele, Ayalkibet M. Seka, Habitamu Taddese, Mengistu A. Jemberrie, Christopher E. Ndehedehe, Solomon S. Demissie, Joseph L. Awange, Jaehak Jeong, David P. Hamilton, Assefa M. Melesse
Summary: Understanding the spatiotemporal trend of land cover change and its impact on hydrology, ecosystems, and the environment is crucial. This study analyzed the land cover change in a specific area using remotely-sensed data and assessed its relationship with watershed characteristics. The findings revealed an increase in agricultural land and a decrease in bushland, grazing land, and forest, influenced by soil type, fertility, and slope.
Review
Environmental Sciences
Sean Waters, David Hamilton, Gang Pan, Steven Michener, Shaun Ogilvie
Summary: Nutrient enrichment in lakes is a global issue that affects the health, biodiversity, and services provided by lakes. The use of oxygen nanobubbles as a geoengineering technology shows promise in remediating low oxygen conditions and alleviating eutrophication linked to high internal nutrient loads. However, further research is needed to address scalability, environmental impacts, and social acceptance.
Article
Environmental Sciences
Rohan Eccles, Hong Zhang, David Hamilton, Ralph Trancoso, Jozef Syktus
Summary: This study examines the impacts of climate change on streamflow and water quality in the subtropical Logan-Albert catchment in Australia. The results show that climate warming may lead to decreased streamflow and contaminant loads, with the largest decreases predicted during the dry season. This could result in reduced flushing and increased importance of point source loads in urbanizing catchments.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2023)
Article
Engineering, Civil
Melanie E. Roberts, Donghwan Kim, Jing Lu, David P. Hamilton
Summary: Hysteresis refers to the variable responses of ecological systems to external stimuli or stressors. Understanding and quantifying hysteresis is crucial for understanding system behavior, modeling, and comparisons within and between systems. HARP is a new tool introduced to describe and quantify hysteresis, and it can be used on complex discharge-concentration data and supports statistical analysis.
JOURNAL OF HYDROLOGY
(2023)
Article
Biology
Man Xiao, Michele A. Burford, Matthew J. Prentice, Elena F. Galvanese, Ann Chuang, David P. Hamilton
Summary: The inter-relationships between cellular phosphorus (P) storage, dissolved inorganic P (DIP) uptake affinity, alkaline phosphatase activity (APA) and dissolved inorganic nitrogen (DIN) concentrations were studied in two ubiquitous diazotrophic freshwater cyanobacteria, Raphidiopsis raciborskii and Chrysosporum ovalisporum. The study showed that DIP uptake of individual strains followed Michaelis-Menten kinetics, but differed with DIN and P availability, and between growth stages. Our results indicate that cyanobacterial species and strains differ in their strategies to P limiting conditions, and highlight the interplay between N and P.
PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES
(2023)
Article
Environmental Studies
Gebiaw T. Ayele, Bofu Yu, David P. Hamilton
Summary: This study aimed to investigate the impacts of future land use change and climate change on streamflow and nutrient load. The results showed that increasing forest coverage can decrease nutrient load, while climate change may lead to increased flow and nutrient load. Additionally, land use change can moderate the impacts of climate change on nutrient load.