scholarly journals Impact of hydropower dam on total suspended sediment and total organic nitrogen fluxes of the Red River (Vietnam)

2020 ◽  
Vol 383 ◽  
pp. 367-374
Author(s):  
Nhu Da Le ◽  
Thi Phuong Quynh Le ◽  
Thi Xuan Binh Phung ◽  
Thi Thuy Duong ◽  
Orange Didier
Keyword(s):  
Suspended Sediment ◽  
Organic Nitrogen ◽  
Red River ◽  
Total Suspended Sediment ◽  
Wet Season ◽  
Annual Average ◽  
Total Organic Nitrogen ◽  
Sediment Loads ◽  
The Relationship ◽  
Experimental Equation

Abstract. The Red River is a typical example of the Southeast Asian rivers, which has been strongly affected by human activities. This paper analyses the change of total suspended sediment (TSS) load of the Red River from 1960 to 2015 in which numerous new dams in both China and Vietnam have been constructed. A strong decrease of TSS load of the whole Red River (from 79±26×106 t yr−1 in 1960s to 6±1×106 t yr−1 in 2010s) allocated to the dam impoundments in spite of population and deforestation increase. Base on the experimental equation describing the relationship between TSS and total organic nitrogen (TON) concentrations, and on the available data of TSS concentration and river discharge, the longterm TON concentrations and fluxes were calculated for the three tributaries and the whole Red River. The annual average of TON concentrations spatially varied from 0.41 to 3.19 mg L−1, averaging 0.98 mg L−1 for the whole period; the lowest was found for the Da River where the new dams have been impounded. The highest TON concentrations and fluxes occurred in the wet season in relationship with the highest sediment loads and river discharges. The riverine TON fluxes transferred to estuary significantly decreased from 141×103±38×103 t yr−1 (equivalent to 902±247 kg km−2 yr−1) in 1960s to 32×103±5×103 t yr−1 (equivalent to 207±35 kg km−2 yr−1) in 2010s. The TSS flux decrease has driven a clear reduction of associated elements like nitrogen, which let to hypothesis a change in biogeochemical processes in the coastal zone.

scholarly journals CARBON ABSORPTION CAPABILITY THE WATERS IN THE RUPAT STRAIT OF RIAU PROVINCE

2018 ◽  
Vol 46 (2) ◽  
pp. 59
Author(s):  
Siti Ramlah Hasibuan ◽  
Rifardi Rifardi ◽  
Sampe Harahap
Keyword(s):  
Suspended Sediment ◽  
Primary Productivity ◽  
Suspended Sediments ◽  
Sediment Concentration ◽  
Carbon Uptake ◽  
Total Suspended Sediment ◽  
Carbon Absorption ◽  
The Relationship ◽  
Polluted Waters ◽  
Total Diversity

The purpose of this study isto analyze the uptake of carbon in polluted waters and unpolluted based on suspended sediment concentration in Rupat Strait. This study used multivariate statistics of Principle Component Analysis (PCA) and regression analysis to clarity the relationship between suspended sediments and primary productivity with carbon uptake. The results indicate that carbon uptake in polluted waters range from 0.023-0.026 tonC/m2/year and unpolluted ranged from 0.034- 0.038 tonC/m2/year. PCA analysis shows that the two main axes (F1 and F2) can represent 82.26% of the total diversity of distribution, indicate the contribution of F1 is 70.08% and F2 is 12.18%. The relationship between total suspended sediment with carbon uptake clearly show if total suspended sediment is higher, the carbon uptake will be lower. On the other hand the relationship between primary productivity and carbon uptake, indicate abundance of primary productivity, the carbon uptake will behigher. 

Statistical power of detecting trends in total suspended sediment loads to the Great Barrier Reef

2012 ◽  
Vol 65 (4-9) ◽  
pp. 203-209 ◽  
Author(s):  
Ross Darnell ◽  
Brent Henderson ◽  
Frederieke J. Kroon ◽  
Petra Kuhnert
Keyword(s):  
Great Barrier Reef ◽  
Suspended Sediment ◽  
Statistical Power ◽  
Barrier Reef ◽  
Total Suspended Sediment ◽  
Sediment Loads

scholarly journals Response of Total Suspended Sediment and Chlorophyll-a Concentration to Late Autumn Typhoon Events in the Northwestern South China Sea

2021 ◽  
Vol 13 (15) ◽  
pp. 2863
Author(s):  
Junyi Li ◽  
Huiyuan Zheng ◽  
Lingling Xie ◽  
Quanan Zheng ◽  
Zheng Ling ◽  
...  
Keyword(s):  
South China Sea ◽  
Continental Shelf ◽  
Suspended Sediment ◽  
Chlorophyll A ◽  
South China ◽  
Total Suspended Sediment ◽  
Offshore Area ◽  
Chl A ◽  
Late Autumn ◽  
China Sea

Strong typhoon winds enhance turbulent mixing, which induces sediment to resuspend and to promote chlorophyll-a (Chl-a) blooms in the continental shelf areas. In this study, we find limited Chl-a responses to three late autumn typhoons (typhoon Nesat, Mujigae and Khanun) in the northwestern South China Sea (NWSCS) using satellite observations. In climatology, the Chl-a and total suspended sediment (TSS) concentrations are high all year round with higher value in autumn in the offshore area of the NWSCS. After the typhoon passage, the Chl-a concentration increases slightly (23%), while even TSS enhances by 280% on the wide continental shelf of the NWSCS. However, in the southern area, located approximately 100 km from the typhoon tracks, both TSS and Chl-a concentrations increase 160% and 150% after typhoon passage, respectively. In the deeper area, the increased TSS concentration is responsible for the considerable increase of the Chl-a. An empirical analysis is applied to the data, which reveals the TSS and Chl-a processes during typhoon events. The results of this study suggest a different mechanism for Chl-a concentration increase and thus contribute toward further evaluation of typhoon-induced biological responses.

scholarly journals Spatial Variation of the Relationship between PM2.5Concentrations and Meteorological Parameters in China

2015 ◽  
Vol 2015 ◽  
pp. 1-15 ◽  
Author(s):  
Gang Lin ◽  
Jingying Fu ◽  
Dong Jiang ◽  
Jianhua Wang ◽  
Qiao Wang ◽  
...  
Keyword(s):  
Negative Correlation ◽  
Meteorological Parameters ◽  
Semiarid Region ◽  
Strong Positive Correlation ◽  
Annual Average ◽  
Strong Negative Correlation ◽  
Positive Correlation ◽  
Humid Region ◽  
The Relationship ◽  
Warm Temperate

Epidemiological studies around the world have reported that fine particulate matter (PM2.5) is closely associated with human health. The distribution of PM2.5concentrations is influenced by multiple geographic and socioeconomic factors. Using a remote-sensing-derived PM2.5dataset, this paper explores the relationship between PM2.5concentrations and meteorological parameters and their spatial variance in China for the period 2001–2010. The spatial variations of the relationships between the annual average PM2.5, the annual average precipitation (AAP), and the annual average temperature (AAT) were evaluated using the Geographically Weighted Regression (GWR) model. The results indicated that PM2.5had a strong and stable correlation with meteorological parameters. In particular, PM2.5had a negative correlation with precipitation and a positive correlation with temperature. In addition, the relationship between the variables changed over space, and the strong negative correlation between PM2.5and the AAP mainly appeared in the warm temperate semihumid region and northern subtropical humid region in 2001 and 2010, with some localized differences. The strong positive correlation between the PM2.5and the AAT mainly occurred in the mid-temperate semiarid region, the humid, semihumid, and semiarid warm temperate regions, and the northern subtropical humid region in 2001 and 2010.

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