Two wetland systems (conventional and structurally modified) were studied for the removal of organics and nutrients from municipal wastewater. Each system consisted of three vertical flow (VF) wetlands, which were filled with agricultural, construction waste materials and planted with and The wetland units were operated under constant and consecutive shock hydraulic load (HL). Input nutrients and organics load across the wetland units ranged between 4.0-116.0 g N/md, 0.5-23.0 g P/md, 1.0-527.0 g biochemical oxygen demand (BOD)/md and 16.0-686.0 g chemical oxygen demand (COD)/md. Nitrification and organic carbon availability controlled nitrogen (N) removals in first and third stage VF wetlands, respectively, during constant load phase; organics removals were influenced by dissolved oxygen concentration of municipal wastewater. Second stage VF wetlands (of both systems) were inefficient in terms of COD removals during shock load periods, which were counter-balanced by first and third stages. First stage VF wetlands achieved higher N removal rates than following stages during shock load periods. Wetland maturation provided a buffer against substantial HL increment and sharp input load decrease in latter shock and recovery phases, respectively. Agricultural waste (sugarcane bagasse) provided carbon to support denitrification; construction materials (recycled brick and crushed mortar) removed phosphorus (P) from wastewater through adsorption. Coliform removal in VF wetlands was achieved through media filtration. Structurally modified system achieved higher removals than the conventional system. BOD, COD, total nitrogen and NH-N removal percentage across two systems ranged between 76-79%, 59-63%, 73-77% and 90-95%, respectively. In general, this study enlightens potential application of appropriate waste materials for wastewater treatment.
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http://dx.doi.org/10.1080/09593330.2019.1655592 | DOI Listing |
Int J Biol Macromol
December 2024
College of Forestry, Fujian Colleges and Universities Engineering Research Institute of Conservation and Utilization of Natural Bioresources, Fujian Agriculture and Forestry University, Fuzhou 350002, Fujian, China. Electronic address:
Fruit features are crucial for plant propagation, population growth, biodiversity preservation, and evolutionary survival. However, the synergistic regulatory mechanisms underlying the development of fruit traits such as color, shape and duration are unclear. Euscaphis japonica, whose fruits have a red-winged pericarp and persist for a long period of time, is an important ornamental plant in eastern Asia.
View Article and Find Full Text PDFSci Total Environ
December 2024
Xiaoliang Research Station of Tropical Coastal Ecosystems, Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, the CAS Engineering Laboratory for Ecological Restoration of Island and Coastal Ecosystems, Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, PR China; South China National Botanical Garden, Guangzhou 510650, PR China; College of Ecology, Hainan University, Haikou 570228, PR China; Southern Marine Science and Engineering Guangdong Laboratory, Zhuhai 519082, PR China. Electronic address:
With global climate warming and ocean acidification, mineral amendments in coastal areas have emerged as a promising strategy to bolster carbon sinks and alkalinity. However, most research has predominantly focused on carbon dioxide (CO) absorption, with limited exploration of methane (CH) reduction despite its more potent greenhouse effect. To address this gap, our study conducted a microcosm manipulative experiment employing coastal wetlands sediments to elucidate the regulatory effects of various mineral amendments on greenhouse gas emissions (including CO and CH) and seawater alkalinity.
View Article and Find Full Text PDFChemosphere
December 2024
Federal University of Tecnhology - Paraná (UTFPR) - Civil Construction Academic Department, Deputado Heitor de Alencar Furtado St., 5000, Ecoville, 81280-340, Curitiba, Paraná, Brazil. Electronic address:
Operational strategies have been applied in constructed wetlands to optimize the removal of nutrients and hormones that are still a concern in wastewater treatment. The strategy of intensifying intermittent aeration was investigated in two microcosm-scale vertical-flow constructed wetlands (VFCWs) planted with Eichhornia crassipes onto autoclaved aerated concrete (AC) in the removal of nutrients, estrone (E1), 17β-estradiol (E2) and 17α-ethinylestradiol (EE2). CW-1 (2.
View Article and Find Full Text PDFEnviron Sci Technol
December 2024
School of Engineering and Applied Science, Harvard University, Cambridge, Massachusetts 02138, United States.
Rice cultivation is one of the major anthropogenic methane sources in China and globally. However, accurately quantifying regional rice methane emissions is often challenging due to highly heterogeneous emission fluxes and limited measurement data. This study attempts to address this issue by quantifying regional methane emissions from rice cultivation with a high-resolution inversion of satellite methane observations from the Tropospheric Monitoring Instrument (TROPOMI).
View Article and Find Full Text PDFSci Total Environ
December 2024
Department of Environmental Engineering, College of Art, Culture, and Engineering, Kangwon National University, 1 Kangwondaehak-gil, Chuncheon-si, Gangwon-do 24341, Republic of Korea; Department of Integrated Energy and Infrasystem, Kangwon National University, Kangwondaehak-gil, 1, Chuncheon-si, Gangwon-do 24341, Republic of Korea. Electronic address:
This study investigated the transformative characteristics of dissolved organic matter (DOM) within constructed wetlands (CWs) and elucidated the distinct interplay between aquatic DOM and soil organic matter (SOM) during different treatment stages. Through comprehensive analyses, including water quality assessments, molecular weight distribution, fluorescence spectrometry, and molecular structure analysis, our investigation revealed profound transformations in aquatic DOM characteristics facilitated by CWs. Notably, the significant increase in dissolved organic carbon (DOC) concentrations within the Typha pond underscored the pivotal role of anaerobic decomposition in organic matter accumulation.
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