scholarly journals Spatiotemporal Dynamics of Nitrogen Budgets under Anthropogenic Activities in Metropolitan Areas

2021 ◽  
Vol 13 (4) ◽  
pp. 2006
Author(s):  
Ning Ding ◽  
Jingfeng Zhu ◽  
Xiao Li ◽  
Xiangrong Wang
Keyword(s):  
Anthropogenic Activities ◽  
River System ◽  
Yangtze River Delta ◽  
Fertilizer Efficiency ◽  
Land Use Pattern ◽  
Human Disturbances ◽  
Nitrogen Budgets ◽  
Metropolitan Regions ◽  
Close Relationship ◽  
Anthropogenic Nitrogen

The rapid growth of metropolitan regions is closely associated with high nitrogen (N) flows, which is known as the most important reason for widespread water pollution. It is, therefore, crucial to explore the spatiotemporal patterns of N budgets under intensive human activity. In this study, we estimated the long-term (2000–2015) N budgets by integrating the net anthropogenic nitrogen input (NANI) and the export coefficient model (ECM) in the Yangtze River Delta Urban Agglomeration (YRDUA), a typical metropolitan area with strong human disturbances. The results revealed that the NANI decreased by 10% from 2000 to 2015, while N exports showed a 6% increase. Hotspots for N budgets were found in the northeastern areas, where cropland and construction land were dominant. The linear regression showed a close relationship between the NANI and N export, and about 18% of the NANI was exported into the river system. By revealing the critical sources and drivers of N budgets over time, our work aimed to provide effective information for regional policy on nitrogen management. Future strategies, such as improving the fertilizer efficiency, optimizing the land use pattern, and controlling the population density, are necessary in order to address the environmental challenge concerns of excessive N.

Impacts of urbanization on river system structure: a case study on Qinhuai River Basin, Yangtze River Delta

2014 ◽  
Vol 70 (4) ◽  
pp. 671-677 ◽  
Author(s):  
Xiaomin Ji ◽  
Youpeng Xu ◽  
Longfei Han ◽  
Liu Yang
Keyword(s):  
River Basin ◽  
River System ◽  
Yangtze River Delta ◽  
System Structure ◽  
River Channels ◽  
Stream Structure ◽  
Impervious Area ◽  
The Status ◽  
Urbanized Areas ◽  
Qinhuai River

Stream structure is usually dominated by various human activities over a short term. An analysis of variation in stream structure from 1979 to 2009 in the Qinhuai River Basin, China, was performed based on remote sensing images and topographic maps by using ArcGIS. A series of river parameters derived from river geomorphology are listed to describe the status of river structure in the past and present. Results showed that urbanization caused a huge increase in the impervious area. The number of rivers in the study area has decreased and length of rivers has shortened. Over the 30 years, there was a 41.03% decrease in river length. Complexity and stability of streams have also changed and consequently the storage capacities of river channels in intensively urbanized areas are much lower than in moderately urbanized areas, indicating a greater risk of floods. Therefore, more attention should be paid to the urban disturbance to rivers.

scholarly journals Microplastics Determination in the Rivers with Different Urbanisation Variances: A Case Study in Kuching City, Sarawak, Malaysia

2020 ◽  
Vol 10 (2) ◽  
pp. 116-125
Author(s):  
Georgina Johnson ◽  
Wen San Hii ◽  
Samuel Lihan ◽  
Meng Guan Tay
Keyword(s):  
Anthropogenic Activities ◽  
River System ◽  
Anthropogenic Activity ◽  
Domestic Waste ◽  
Shape Identification ◽  
Suburban Areas ◽  
Sampling Locations ◽  
The Relationship ◽  
Main Factor

The presence of microplastics in aquatic systems is mainly due to the anthropogenic activities such as domestic waste dumping. Undeniably, rivers either in urban or suburban areas are always a waste dumpling sites from the surrounding residences. Thus, the purpose of this study was to determine the relationship between microplastic abundance and different degree of urbanization across Kuching in Sarawak. Three sampling locations with different degrees of urbanisation had been studied across Kuching. A total of 137 pieces of microplastics were collected along the study and analysed using stereoscopic microscope for the shape identification and FTIR spectrophotometer for functional groups present in the microplastics. Filament was the most abundant microplastics shape found, whereas the IR results showed that ethylenevinylacetate (9%), polyamides or nylon (15%), polypropylene (42%), poly(methylmethacrylate) (16%) and polystyrene (18%) were found in the study. The most abundant microplastics in the water samples was polypropylene (42%), whereas ethylenevinylacetate (9%) was the least. The degree of urbanisation does not directly relate to the microplastic present in the river system in Kuching City, but the anthropogenic activity is the main factor that affecting the microplastic abundance in the river.   Keywords: anthropologenic activity, FTIR, microplastics, polymer identification, urban, sub-urban

scholarly journals Effects of land use and water quality on greenhouse gas emissions from an urban river system

2020 ◽  
Author(s):  
Long Ho ◽  
Ruben Jerves-Cobo ◽  
Matti Barthel ◽  
Johan Six ◽  
Samuel Bode ◽  
...  
Keyword(s):  
Water Quality ◽  
Land Use ◽  
Urban Areas ◽  
Anthropogenic Activities ◽  
Ghg Emissions ◽  
Flow Characteristics ◽  
River System ◽  
Urban River ◽  
Polluted Water ◽  
Land Use Types

Abstract. Rivers act as a natural source of greenhouse gases (GHGs) that can be released from the metabolisms of aquatic organisms. Anthropogenic activities can largely alter the chemical composition and microbial communities of rivers, consequently affecting their GHG emissions. To investigate these impacts, we assessed the emissions of CO2, CH4, and N2O from Cuenca urban river system (Ecuador). High variation of the emissions was found among river tributaries that mainly depended on water quality and neighboring landscapes. By using Prati and Oregon Indexes, a clear pattern was observed between water quality and GHG emissions in which the more polluted the sites were, the higher were their emissions. When river water quality deteriorated from acceptable to very heavily polluted, their global warming potential (GWP) increased by ten times. Compared to the average estimated emissions from global streams, rivers with polluted water released almost double the estimated GWP while the proportion increased to ten times for very heavily polluted rivers. Conversely, the GWP of good-water-quality rivers was half of the estimated GWP. Furthermore, surrounding land-use types, i.e. urban, roads, and agriculture, significantly affected the river emissions. The GWP of the sites close to urban areas was four time higher than the GWP of the nature sites while this proportion for the sites close to roads or agricultural areas was triple and double, respectively. Lastly, by applying random forests, we identified dissolved oxygen, ammonium, and flow characteristics as the main important factors to the emissions. Conversely, low impact of organic matter and nitrate concentration suggested a higher role of nitrification than denitrification in producing N2O. These results highlighted the impacts of land-use types on the river emissions via water contamination by sewage discharges and surface runoff. Hence, to estimate of the emissions from global streams, both their quantity and water quality should be included.

River System Connectivity Analysis of Wuxi’s Central Urban Area Based on Graph Theory

2012 ◽  
Vol 212-213 ◽  
pp. 543-548 ◽  
Author(s):  
Liu Yan Wang ◽  
You Peng Xu ◽  
Ming Jing Yu
Keyword(s):  
Graph Theory ◽  
Urban Area ◽  
Water Environment ◽  
River System ◽  
Yangtze River Delta ◽  
River Network ◽  
Structure Stability ◽  
Network Graph ◽  
Stream Structure ◽  
Wuxi City

Wuxi City is located in the hinterland of Taihu Basin and an important city in Yangtze River Delta Region with a prosperous economy. In the process of urban development, the river system pattern changes a lot. It has an impact on water environment, water ecology and other fields. The central urban area of Wuxi City was selected as the study area. Based on the river system of three periods: 1960s, 1980s and 2009, the rivers were classified into three levels according to the width of channels. The length, acreage and stream structure parameters were calculated. Then from the view of Graph Theory, river system was expressed as network graph, and the vertices, edges and degree of vertices were analyzed. The results show that the changes of rivers of different levels and lakes are not completely the same, but still appear a decreasing trend in general. The river network density and water surface ratio become smaller. Also the complexity and structure stability of river network weaken. The conclusions that the river evolution tends to be trunk and single, the stream structure is simplified and the connectivity of rivers and lakes reduces are verified by the analysis based on Graph Theory as well.

scholarly journals Characteristics and Sources of Black Carbon Aerosol in a Mega-City in the Western Yangtze River Delta, China

Atmosphere ◽  
2020 ◽  
Vol 11 (4) ◽  
pp. 315
Author(s):  
Jun Li ◽  
Lei Jiang ◽  
Cheng Chen ◽  
Dantong Liu ◽  
Songshan Du ◽  
...  
Keyword(s):  
Black Carbon ◽  
Coating Thickness ◽  
Yangtze River ◽  
Anthropogenic Activities ◽  
Chemical Species ◽  
Yangtze River Delta ◽  
River Delta ◽  
Traffic Emissions ◽  
Potential Contribution ◽  
Coated Particle

A single particle soot photometer (SP2) was deployed in urban Nanjing, located in the Yangtze River Delta (China), to investigate the mixing state and sources of ambient refractory black carbon (rBC) from 26 January to 25 February 2014, along with an in-situ measurement of submicron aerosol chemical species by an aerodyne aerosol chemical speciation monitor (ACSM). The results showed that anthropogenic activities associated with firework emissions can be a significant source for rBC-containing particles during the period of the Chinese New Year, resulting from the evident peaks of rBC at midnight. During the residual periods, namely regular day (RD), the diurnal cycles of rBC presented two typical peaks that can be attributed to a synergistic influence of local traffic emissions and boundary layer changes throughout a day. Three coating factors, including organics, sulfate, and nitrate (-rich), were resolved using a positive matrix factorization (PMF) approach to explain the potential contribution of non-rBC coatings (i.e., organics, sulfate, and nitrate) to the coating thickness of rBC-containing particles. As the results show, organic aerosols (OAs) might be a major contributor to the coating thickness of rBC-coating particles during the whole period. The relative coating thickness (a ratio between coated particle size to BC core) exhibited a positive relationship with sulfate, indicative of the favorable coating factor during the episode caused by firework emissions. Source apportionment of rBC was performed via a multiple linear regression between the total rBC mass and each ACSM-PMF factor (rBC-ACSM-PMF). On average, biomass burning emissions accounted for 43%, being the largest contributor during the RD period, whereas local traffic emissions played a major role during the new year time.

scholarly journals Assessment of the Impacts of Anthropogenic Activities on a Large River Using Longfin Eel as a Bioindicator

2020 ◽  
Vol 12 (20) ◽  
pp. 8412
Author(s):  
Olivier Champeau ◽  
James M. Ataria ◽  
Grant L. Northcott ◽  
Gen Kume ◽  
Andrew Barrick ◽  
...  
Keyword(s):  
Native Species ◽  
Anthropogenic Activities ◽  
Economic Value ◽  
River System ◽  
Large River ◽  
Chemical Contamination ◽  
Bioindicator Species ◽  
Tissue Samples ◽  
Anthropogenic Stressors ◽  
Residential Land Use

The Matāura River is the sixth largest river system in New Zealand and has long been subject to agricultural, industrial, and residential land use activities. The catchment has economic value and is of great cultural importance for local Māori, who have concerns over potential adverse impacts that anthropogenic stressors exert on the health of the river. There is a dearth of information on the impacts of these stressors towards the health of native species such as the longfin eel Anguilla dieffenbachii. This study assessed the environmental status of the Matāura River using biological and chemical methodologies incorporating A. dieffenbachii as a bioindicator species for exposure to multiple anthropogenic stressors. A range of biomarkers were measured in caged and wild-caught eels (when available) to characterize site-specific responses to anthropogenic stressors. While there was no clear indication of cumulative impacts moving from pristine headwaters to the lower reaches of the Matāura River, biomarkers of xenobiotic metabolization were induced in A. dieffenbachia and there was evidence of chemical contamination in sediment and tissue samples.

Paleolimnology of a fluvial lake downstream of Lake Superior and the industrialized region of Sault Saint Marie

2005 ◽  
Vol 62 (11) ◽  
pp. 2586-2608 ◽  
Author(s):  
Euan D Reavie ◽  
John A Robbins ◽  
Eugene F Stoermer ◽  
Marianne SV Douglas ◽  
Gail E Emmert ◽  
...  
Keyword(s):  
20Th Century ◽  
Anthropogenic Activities ◽  
Lake Superior ◽  
Sediment Cores ◽  
Chemical Properties ◽  
River System ◽  
Geochemical Data ◽  
Fluvial Lake ◽  
Lotic System ◽  
Contaminant Metals

A paleolimnological study was undertaken to describe the past environment of the St. Mary's River downstream of Lake Superior. Two sediment cores were obtained from the deepest part of Lake George, a fluvial lake in the river system. Rigorous analyses of radionuclides (210Pb, 226Ra, and 137Cs) and chemical properties provided an accurate sediment chronology. More than 450 diatom species from 47 genera were identified. Diatom and geochemical data indicated gradual environmental change in response to anthropogenic activities, including logging, hydrologic manipulation, and steel, leather, and paper industries. A decline in water quality occurred gradually from the late 1800s through the 20th century in response to human activities, as was apparent from an increase in eutrophic–planktonic diatom taxa. A decline in benthic taxa and an increase in contaminant metals were also contemporaneous with impacts during the 20th century. Subfossil diatoms were similar to those recorded in paleolimnological investigations from the Great Lakes. However, diatom profiles indicate that the algal supply from upstream Lake Superior has been minimal and that the cores mainly reflect environmental characteristics of the near-upstream environment. Despite stochastic sedimentary regimes and complex habitats in the lotic system, this study reinforces the value of river paleolimnology at carefully selected sites.

scholarly journals Rapid assessment of butterfly diversity of two proposed Community Resource Management Areas (CREMAs) in the Western North Region of Ghana: Implication for conservation

2020 ◽  
Vol 21 (8) ◽  
Author(s):  
Rosina Kyerematen ◽  
CHRISTIANA NAA DEEDEI TETTEY ◽  
ROGER SIGISMUND ANDERSON
Keyword(s):  
Resource Management ◽  
Forest Disturbance ◽  
Anthropogenic Activities ◽  
Rapid Assessment ◽  
Free Access ◽  
Community Resource ◽  
Human Disturbances ◽  
Butterfly Diversity ◽  
Community Resource Management ◽  
Butterfly Population

Abstract. Tettey CND, Anderson RS, Kyerematen R. 2020. Rapid assessment of butterfly diversity of two proposed Community Resource Management Areas (CREMAs) in the Western North Region of Ghana: Implication for conservation. Biodiversitas 21: 3699-3706. Community Resource Management Areas (CREMAs) are non-reserved land masses with local communities living in them that contain important components of biodiversity and are open to free access. Biodiversity in these off-reserve areas in Ghana is fast depleting due to unsustainable anthropogenic activities. The Rapid Biodiversity Assessment (RBA) method was conducted in the proposed Manzan and Yawmatwa CREMAs in Sefwi-Debiso; in the Western North Region of Ghana using butterflies as indicator taxa to estimate species richness and diversity in two proposed CREMAs to prioritize these rapidly diminishing forest areas for conservation. A total of 1,352 individual butterflies were recorded at the end of a two-week rapid assessment; with 83 species belonging to five families (Nymphalidae, Papilionidae, Pieridae, Lycaenidae, and Hesperiidae). The findings of the study revealed that 38.5% of the butterfly population belongs to species associated with severe forest disturbance; indicating that these ecosystems are gradually being threatened by ongoing anthropogenic activities. Management efforts aimed at butterfly conservation should be geared towards protecting these proposed CREMAs from excessive human disturbances.

scholarly journals Assessment of the Impacts of Anthropogenic Activities on a Large River Using Longfin Eel as a Bioindicator

2020 ◽  
Author(s):  
Olivier Champeau ◽  
James Ataria ◽  
Grant Northcott ◽  
Gen Kume ◽  
Andrew Barrick ◽  
...  
Keyword(s):  
Native Species ◽  
Anthropogenic Activities ◽  
Economic Value ◽  
River System ◽  
Large River ◽  
Chemical Contamination ◽  
Bioindicator Species ◽  
Anthropogenic Stressors ◽  
Environmental Status ◽  
Residential Land Use

The Matāura River is the sixth largest river system in New Zealand and has long been subject to agricultural, industrial, and residential land use activities. The catchment has geographic and economic value and is of great cultural importance for local Māori, who have concerns over potential adverse impacts that anthropogenic stressors exert on the health of the river. There is a dearth of information on the impacts of these stressors towards the health of native species such as the longfin eel Anguilla dieffenbachii. This study assessed the environmental status of the Matāura River using biological and chemical methodologies incorporating A. dieffenbachii as a bioindicator species for exposure to combined anthroprogenic stressors. A range of biomarker endpoints were measured in caged and wild-caught eels (when available) to characterize site-specific responses to combined anthropogenic stressors. While there was no clear indication of cumulative impacts moving from pristine headwaters to the lower reaches of the Matāura River biomarkers of xenobiotic metabolization were induced in A. dieffenbachia and there was evidence of chemical contamination in sediments and tissues.

Sign in / Sign up

Export Citation Format

Share Document