scholarly journals Horizontal Distribution of Cadmium in Urban Constructed Wetlands: A Case Study

2021 ◽  
Vol 13 (10) ◽  
pp. 5381
Author(s):  
Zheng Zeng ◽  
Wei-Ge Luo ◽  
Fa-Cheng Yi ◽  
Feng-Yu Huang ◽  
Cheng-Xia Wang ◽  
...  
Keyword(s):  
Constructed Wetlands ◽  
Constructed Wetland ◽  
Cost Effective ◽  
Horizontal Distribution ◽  
Factors Affecting ◽  
Bacterial Uptake ◽  
Cd Distribution ◽  
Water Plants ◽  
Cd Removal

Here, we used a radioactive distribution approach for water samples from the Liu Shao Yan constructed wetland to investigate the horizontal advection of cadmium (Cd) in this urban constructed wetland. The objective of this study was to assess the effectiveness of Cd removal in constructed wetlands. Additionally, this study examined the factors affecting the horizontal distribution of Cd. Sediment samples were collected from an enclosed wet area. A predictive advection model was executed using a combination of observed Cd concentrations and predicted Cd concentrations from a genetic algorithm–backpropagation artificial neural network (GA–BPANN). A coefficient of variation was used to assess differences in Cd distribution due to flow rate, precipitation, and water plants. Scanning electronic microscopy–energy dispersive spectrometry (SEM–EDS) results suggested that the plant species Pontederia cordata could absorb Cd, but the influence was negligible. All plants investigated in our experiment were unsuitable for Cd removal. However, predictions from the GA–BPANN algorithm indicated that 13–25% of Cd loading was efficiently removed by constructed wetland, which mainly resulted from sediment sorption, bacterial uptake, and the dilution caused by water advection. Consequently, we conclude that the constructed wetlands are an environmentally friendly and cost-effective technology that can remove Cd to a certain extent.

Cost-effective fuel treatment planning: a theoretical justification and case study

2020 ◽  
Vol 29 (1) ◽  
pp. 42
Author(s):  
Jason Kreitler ◽  
Matthew P. Thompson ◽  
Nicole M. Vaillant ◽  
Todd J. Hawbaker
Keyword(s):  
Cost Effectiveness ◽  
Ecosystem Services ◽  
Treatment Planning ◽  
Cost Effective ◽  
Cost Effectiveness Ratio ◽  
Fuel Treatments ◽  
Fuel Treatment ◽  
Factors Affecting ◽  
Planning Algorithm

Modelling the spatial prioritisation of fuel treatments and their net effect on values at risk is an important area for applied work as economic damages from wildfire continue to grow. We model and demonstrate a cost-effective fuel treatment planning algorithm using two ecosystem services as benefits for which fuel treatments are prioritised. We create a surface of expected fuel treatment costs to incorporate the heterogeneity in factors affecting the revenue and costs of fuel treatments, and then prioritise treatments based on a cost-effectiveness ratio to maximise the averted loss of ecosystem services from fire. We compare treatment scenarios that employ cost-effectiveness with those that do not, and use common tools and models in a case study of the Sisters Ranger District on the Deschutes National Forest in central Oregon, USA. Using cost-effectiveness not only increases the expected averted losses from fuel treatments, but it also allows a larger area to be treated for the same cost, simply by incorporating costs and cost-effectiveness into the prioritisation routine. These results have considerable implications for policymakers and land managers trying to minimise risk. Incorporating costs into the spatial planning of treatments could allow more effective outcomes without increasing fuel treatment budgets.

Factors Affecting The Sustainability Of The Asphalt Roads: A Case Study Of Irbid Inner Ring Road, Jordan

2011 ◽  
Vol 1 (5) ◽  
pp. 93-94
Author(s):  
Eng. Nasr Ahmad Eng. Nasr Ahmad ◽  
◽  
Dr. Mihai Iliescu
Keyword(s):  
Factors Affecting ◽  
Ring Road

Factors Affecting Financial Literacy of Vietnamese Adults: A Case Study for Hanoi and Nghe An

2017 ◽  
Vol 33 (2) ◽  
Author(s):  
Tue Nguyen Dang
Keyword(s):  
Higher Education ◽  
Multiple Regression ◽  
Financial Literacy ◽  
Urban Areas ◽  
Logistic Models ◽  
Factors Affecting ◽  
Financial Behaviors ◽  
Financial Decisions ◽  
Literacy Level

This research examines the factors affecting the financial literacy of Vietnamese adults. Using a sample of 266 observations of adults in 2 big cities in Vietnam (Hanoi and Vinh in Nghe An Province), the author evaluates the literacy level of adults in these urban areas. The financial literacy of the interviewed people is low. The multiple regression results show that lower financial literacy levels associate with higher age and married status and higher financial literacy levels associate with higher education, more family members, the person making financial decisions and the person attending a useful financial course. This research also explores the association between financial literacy and financial behaviors of individuals employing logistic models. It is found that higher financial literacy associates with less probability of overspending and higher probability of saving money and careful spending. Higher financial literacy is also found to associate with higher probability of opening a savings account and making various investments. 

Enhancement of nitrogen removal in subsurface flow constructed wetlands employing a 2-stage configuration, an unsaturated zone, and recirculation

1995 ◽  
Vol 32 (3) ◽  
pp. 59-67 ◽  
Author(s):  
Kevin D. White
Keyword(s):  
Constructed Wetlands ◽  
Nitrogen Removal ◽  
Constructed Wetland ◽  
Subsurface Flow ◽  
Great Promise ◽  
Effluent Recirculation ◽  
Wetland Treatment ◽  
Subsurface Flow Constructed Wetlands ◽  
Inlet Zone ◽  
Bod Removal

Constructed wetland technology is currently evolving into an acceptable, economically competitive alternative for many wastewater treatment applications. Although showing great promise for removing carbonaceous materials from wastewater, wetland systems have not been as successful at nitrification. This is primarily due to oxygen limitations. Nitrification does occur in conventional wetland treatment systems, but typically requires long hydraulic retention times. This paper describes a study that first evaluated the capability of subsurface flow constructed wetlands to treat a high strength seafood processor wastewater and then evaluated passive aeration configurations and effluent recirculation with respect to nitrogen treatment efficiency. The first stage of a 2-stage wetland treatment system exhibited a relatively short hydraulic retention time and was designed for BOD removal only. The second stage wetland employed an unsaturated inlet zone and effluent recirculation to enhance nitrification. Results indicate that organic loading, and thus BOD removal, in the first stage wetland is key to optimal nitrification. Passive aeration through an unsaturated inlet zone and recirculation achieved up to 65-70 per cent ammonia nitrogen removal at hydraulic retention times of about 3.5 days. Inlet zone configuration and effluent recirculation is shown to enhance the nitrogen removal capability of constructed wetland treatment systems.

Municipal wastewater treatment with pond–constructed wetland system: a case study

2005 ◽  
Vol 51 (12) ◽  
pp. 325-329 ◽  
Author(s):  
X. Wang ◽  
X. Bai ◽  
J. Qiu ◽  
B. Wang
Keyword(s):  
Constructed Wetland ◽  
Municipal Wastewater ◽  
Municipal Wastewater Treatment ◽  
Oxidation Pond ◽  
System A ◽  
Treated Effluent ◽  
Wetland System ◽  
Oxidation Ponds ◽  
Better Than

The performance of a pond–constructed wetland system in the treatment of municipal wastewater in Kiaochow city was studied; and comparison with oxidation ponds system was conducted. In the post-constructed wetland, the removal of COD, TN and TP is 24%, 58.5% and 24.8% respectively. The treated effluent from the constructed wetland can meet the Chinese National Agricultural and Irrigation Standard. The comparison between pond–constructed wetland system and oxidation pond system shows that total nitrogen removal in a constructed wetland is better than that in an oxidation pond and the TP removal is inferior. A possible reason is the low dissolved oxygen concentration in the wetland. Constructed wetlands can restrain the growth of algae effectively, and can produce obvious ecological and economical benefits.

The socio-spatial politics of royalties and their distribution: A case study of the Surat Basin, Queensland

2021 ◽  
pp. 0308518X2110266
Author(s):  
Neil Argent ◽  
Sean Markey ◽  
Greg Halseth ◽  
Laura Ryser ◽  
Fiona Haslam-McKenzie
Keyword(s):  
Cost Effective ◽  
Indigenous Communities ◽  
Energy Extraction ◽  
Grant Application ◽  
Coal Seam Gas ◽  
Spatial Politics ◽  
Developmental Needs ◽  
Development Fund ◽  
Effective Use

This paper is concerned with the socio-spatial and ethical politics of redistribution, specifically the allocation of natural resources rents from political and economic cores to the economic and geographical peripheries whence the resource originated. Based on a case study of the coal seam gas sector in Queensland's Surat Basin, this paper focuses on the operation of the Queensland State Government's regional development fund for mining and energy extraction-affected regions. Employing an environmental justice framework, we critically explore the operation of these funds in ostensibly helping constituent communities in becoming resilient to the worst effects of the ‘staples trap’. Drawing on secondary demographic and housing data for the region, as well as primary information collected from key respondents from mid-2018 to early 2019, we show that funds were distributed across all of the local government areas, and allocated to projects and places primarily on a perceived economic needs basis. However, concerns were raised with the probity of the funds’ administration. In terms of recognition justice, the participation of smaller and more remote towns and local Indigenous communities was hampered by their structural marginalisation. Procedurally, the funds were criticised for the lack of local consultation taken in the development and approval of projects. While spatially concentrated expenditure may be the most cost-effective use of public monies, we argue that grant application processes should be open, transparent and inclusive, and the outcomes cognisant of the developmental needs of smaller communities, together with the need to foster regional solidarity and coherence.

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