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This paper examines the consequences of the hugely successful expansion of South-South Cooperation since the new millennium. For all the achievements, variations and change over the 1950s-late 1990s, 'SSC 1.0' was characterised by relative neglect within the 'international' development community, and by many orthodox and critical scholars. In the chronological schema of the paper, 'SSC 2.0' refers to the period of remarkable expansion from the early 2000s to the present. The emergence of 'SSC 3.0', I suggest, is currently revealed by a discernible set of shifts driven in large part by the expansionary successes of SSC 2.0, as well as other turns in the global political economy. Three contemporary trends are identified: cooperation narratives that are increasingly 'muscular', nationalistic and pragmatic; difficulties sustaining claims to 'non-interference' in partner countries; and the further erosion of ideational and operational distinctiveness. [ABSTRACT FROM AUTHOR]

In this study, we analyzed the influence of coastal zone engineering on suspended sediment concentration (SSC) in the Yangtze River mouth based on HY-1C and Chinese GaoFen (GF) satellite data. The results show that: (1) SSC in the Yangtze River mouth is mainly in the range of 200–1300 mg/L, which changes due to natural factors as well as coastal zone engineering; (2) The sand blocking engineering effectively protects the channel from siltation, and SSC in the central line of the channel is 100–300 mg/L lower than that near the dikes in the north and south; (3) Qingcaosha Reservoir plays a stabilizing role in the hydrodynamic force, promoting the deposition of suspended matter, so that the water in the reservoir is clear. SSC inside the Qingcaosha Reservoir, located in the center of the estuary, is 100–500 mg/L lower than the high SSC water outside the reservoir; (4) The bridges interact with the current, facilitating the transport of local sediment, resulting in the increase in SSC downstream of these bridges, and obvious vortexes appear with the length up to nearly 2400 m; and (5) Corresponding protection and development suggestions were put forward as follows. A linear array of wind power plants can be built near and parallel to dikes and leading jetties; to increase the depth of the southeast end of the reservoir; and the location of the bridge should be selected in the place of river where siltation is easy. This study aimed to study the SSC distribution under the complex impact of coastal zone engineering with satellite and to provide possible improvement suggestions. [ABSTRACT FROM AUTHOR]

We analyzed the influence of a cross-sea bridge on the sea surface temperature (SST) and suspended sediment concentration (SSC) of Hangzhou Bay based on landsat8_TIRS data and HY-1C data using an improved single window algorithm to retrieve the SST and an empirical formula to retrieve the SSC. In total, 375 paired sampling points and 70 transects were taken to compare the SST upstream and downstream of the bridge, and nine transects were taken to compare the SSC. The results show the following. (i) In summer, when the current flows through the bridge pier, the downstream SST of the bridge decreases significantly, with a range of 3.5%; in winter, generally, the downstream SST decreases but does not change as obviously as in summer. The downstream SSC increases obviously. (ii) The range of influence of the bridge pier on the downstream SST is about 0.3–4.0 km in width from the bridge and that on the downstream SSC is approximately 0.3–6.0 km. (iii) When the current flows around the pier, a portion of the flow is dispersed in upward and downward directions; the downward flow generates local scour. When the scouring at the front end of the pier stops, the upward flow behind the pier brings the sediment and the bottom cold water downstream, causing the downstream SST to decrease and the SSC to increase. (iv) The other portion passes around the pier, which generates a wake vortex. Once a wake vortex is released, a low-pressure center appears, sucking the sediment and the bottom cold water to the downstream sea surface, reducing the downstream SST and raising the SSC. (v) The range of reduction of the SST downstream of the bridge is shorter than the range of increase in the SSC. This is because the wake vortices have an effect in the 0.3–4.0 km downstream but not in the 4.0–6.0 km. Therefore, the SST and SSC are affected within the range of 0.3–4.0 km by wake vortices, while in the 4.0–6.0 km region, the SSC is still high due to the transport of sediment by currents. [ABSTRACT FROM AUTHOR]

The concentration of suspended particulate matter in the Yellow River is very high, and the Yellow River is one of the main sources of sediment in China's coastal waters. The diffusion of substances from the Yellow River into the sea is of great significance to the ecological environments of the Bohai Sea and the Yellow Sea. Thus, the transport pathways and mechanisms of sediment delivered by the Yellow River are hot topics. In this paper, transport pathways, seasonal variations and their relationship between them and wind direction and flow field in the Bohai Sea were investigated based on observational data (suspended sediment concentration, temperature, and salinity) and MODIS imagery and ocean current data from ROMS. This study shows that the sediments from the Yellow River are mainly transported outward along two pathways: along the west side of the central Bohai Shoal to the central part of the Bohai Sea and along the Bohai Strait to the Yellow Sea. Winter is the main season for outward expansion. The interannual variation in the pathway exhibits little correlation with the sediment transport volume of the Yellow River, so the re-suspended sediment from the seabed is the source of the outward diffusion of sediment from the Yellow River into the sea. The interannual variations in the two pathways are closely related to sea surface temperature (SST), flow field, wind speed and wind direction. • The sediments from the Yellow River are transported outward mainly along two pathways. • Strong wind waves and strong re-suspension are the main driving forces for the transport of suspended sediments. • Re-suspended sediments are thought to be the main source of the suspended sediment concentration. • The U and V components of the wind affect the transport of suspended sediments. [ABSTRACT FROM AUTHOR]

Black blooms are a serious and complex problem for lake bays, with far-reaching implications for water quality and drinking safety. While Fe(II) and S(-II) have been reported as the most important triggers of this phenomenon, little effort has been devoted in investigating the relationships between Fe(II) and S(-II) and the host of potentially important aquatic factors. However, a model involving many putative predictors and their interactions will be oversaturated and ill-defined, making ordinary least squares (OLS) estimation unfeasible. In such a case, sparsity assumption is typically required to exclude the redundant predictors from the model, either through variable selection or regularization. In this study, Bayesian least absolute shrinkage and selection operator (LASSO) regression was employed to identify the major influence variables from 11 aquatic factors for Fe(II), S(-II), and suspended sediment concentration (SSC) in the Chaohu Lake (Eastern of China) bay during black bloom maintenance. Both the main effects and the interactions between these factors were studied. The method successfully screened the most important variables from many items. The determination coefficients ( R 2 ) showed that all regression equations for Fe(II), S(-II), and SSC were in good agreement with the situation observed in the Chaohu Lake. The outcome of correlation and LASSO regression indicated that total phosphorus (TP) was the single most important factor for Fe(II), S(-II), and SSC in black bloom with explanation ratios (ERs) of 76.1%, 37.0%, and 12.9%, respectively. The regression results showed that the interaction items previously deemed negligible have significant effects on Fe(II), S(-II), and SSC. For the Fe(II) equation, total nitrogen (TN) × dissolved oxygen (DO) and chlorophyll a (CHLA) × oxidation reduction potential (ORP), which contributed 10.6% and 13.3% ERs, respectively, were important interaction variables. TP emerged in each key interaction item of the regression equation for S(-II). Water depth (DEP) × Fe(II) (30.7% ER) was not only the main interaction item, but DEP (5.6% ER) was also an important single factor for the SSC regression equation. It also indicated that the sediment in shallow bay is an important source for SSC in water. The uncertainty of these relationships was also estimated by the posterior distribution and coefficient of variation (CV) of these items. Overall, our results suggest that TP concentration is the most important driver of black blooms in a lake bay, whereas the other factors, such as DO, DEP, and CHLA act in concert with other aquatic factors. There results provide a basis for the further control and management policy development of black blooms.R 2 ) showed that all regression equations for Fe(II), S(-II), and SSC were in good agreement with the situation observed in the Chaohu Lake. The outcome of correlation and LASSO regression indicated that total phosphorus (TP) was the single most important factor for Fe(II), S(-II), and SSC in black bloom with explanation ratios (ERs) of 76.1%, 37.0%, and 12.9%, respectively. The regression results showed that the interaction items previously deemed negligible have significant effects on Fe(II), S(-II), and SSC. For the Fe(II) equation, total nitrogen (TN) × dissolved oxygen (DO) and chlorophyll a (CHLA) × oxidation reduction potential (ORP), which contributed 10.6% and 13.3% ERs, respectively, were important interaction variables. TP emerged in each key interaction item of the regression equation for S(-II). Water depth (DEP) × Fe(II) (30.7% ER) was not only the main interaction item, but DEP (5.6% ER) was also an important single factor for the SSC regression equation. It also indicated that the sediment in shallow bay is an important source for SSC in water. The uncertainty of these relationships was also estimated by the posterior distribution and coefficient of variation (CV) of these items. Overall, our results suggest that TP concentration is the most important driver of black blooms in a lake bay, whereas the other factors, such as DO, DEP, and CHLA act in concert with other aquatic factors. There results provide a basis for the further control and management policy development of black blooms.