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In the present study, 13 endocrine disrupting compounds (EDCs) and their transformation products (TPs) were monitored in Jiulong River and its estuary, China in different seasons. The analytes included antimicrobials [triclosan (TCS) and triclocarbon (TCC)]; estrogens [estrone (E1), estradiol (E2), estriol (E3) and ethinylestradiol (EE2)]; alkylphenol ethoxylates [4-n-nonylphenol (NP) and 4-n-octylphenol (OP)] and the TPs [methyl triclosan (MeTCS), carbanilide (NCC), dichlorocarbanilide, 4-hydroxy estrone (4-OH E1) and 4-hydroxy estradiol (4-OH E2)]. A significant seasonal variation was observed for most EDCs. Approximately, 79% of the total E2 residues were detected in the normal season in comparison with the wet season to indicate recalcitrant behavior of E2 during the normal season. Risk assessment revealed that E2 was most potent among the EDCs to cause highest risk to both vertebrate and invertebrate aquatic species, whereas, E1, EE2, MeTCS and TCS also showed relatively high risk for some surface water aquatic species. Unlabelled Image • 13 endocrine disrupting compounds were investigated in Jiulong river & estuary. • The occurrence and detection frequency of the antimicrobials was highest. • Significant seasonal variation was observed for most of the compounds. • Estradiol (E2) was most potent among these compounds to cause highest risk. [ABSTRACT FROM AUTHOR]

Abstract The urban water ecosystems, such as the landscape ponds are commonly considered under the influence of anthropogenic disturbances, which can lead to the deterioration of the water quality. The prokaryotic communities are considered as one of the best indicators of the water quality. However, there are significant gaps in understanding the ecological processes that shape the composition and function of prokaryotic communities in the urban water ecosystems. Here, we investigated the biogeographic distribution of prokaryotic assemblages in water environments including landscape ponds, drinking water reservoirs, influents (IFs) and effluents (EFs) of wastewater treatment plants of a coastal city (Xiamen), China, by using 16S rDNA amplicon sequencing. Our results indicated that the ponds had higher α-diversity of prokaryotic communities than those in the reservoirs, while there were significant variations in the community compositions among ponds, reservoirs, IFs and EFs. Moreover, ponds harbored a significantly higher proportion of sewage- and fecal-indicator taxa than those in the reservoirs, suggesting the occurrence of exogenous pollution in the urban ponds. Null model analysis revealed that dispersal limitation was the main ecological processes resulting in the divergence of prokaryotic community compositions between ponds and other environments, while dispersal limitation and variable selection played an essential role in the formation of unique prokaryotic assemblages in the reservoirs. Function predication analysis demonstrated that the ponds shared more similar functional profiles with IFs or EFs (e.g., chemoheterotrophy, fermentation, chlorate reducers, nitrate reduction and respiration) than the reservoirs, whereas dominance of photoautotrophy was observed in the reservoirs. Overall, this study provides a profound insight of the ecological mechanisms underlying the responses of prokaryotic communities in the urban landscape ponds to the anthropogenic disturbances. Graphical abstract Image 1 Highlights • Prokaryotic communities were characterized in an urban water ecosystem. • Stochastic processes led to distinct pond communities compared to other habitats. • Deterministic and stochastic processes together shaped pond prokaryotic communities. • Ponds had abundant prokaryotes capable of anaerobic metabolism. Local anthropogenic disturbances and stochastic processes together led to changes in the prokaryotic communities in urban ponds. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this Research paper is to explore the China's relations with Central Asian region and to study its embodied effects on Pakistan. Objectives of the Study: To investigate the strategic depth of China Central Asian relations in the changing paradigm of regional and international politics. To analyze the Pakistan relations with Central Asia and to provide options for CARs to grapple the economic advantages of this regional connectivity of Kashgar to Gwadar through Pakistan China Economic Corridor. Design/Methodology/Approach: This research has been carried out using various techniques; documents based on content analysis, and case studies. Historical, descriptive, comparative and analytical method have been taken into practice on all Qualitative and Quantitative data sources which includes Govt. publications, organizational reports, thesis, academic papers, published, printed sources, Newspapers, Books, Journals, Periodicals, electronic sources and ejournal etc. to acquire the optimal results and conclusions. Research Limitation-This research enshrines only three major areas of cooperation among the triangular relations of Pakistan, China, and Central Asia. These three areas are Energy, Economy and Extremism. The regional and international challenges have also been taken into account. Theoretical Framework A theoretical framework in social science not only enhances credibility of research but also provides the substructure to the research by interpreting the relevant theories related to research objectives. According to the realist school of thought global political system is anarchic one and states are the main actors in this system. Every state peruses her national self-interest based on rationality and there is no any supranational authority to govern the states. Every state has desire of acquiring more and more power to ensure its self-preservation. Power is perpetual as well rational concept. It does not exist in vacuum but in relations with other state. China is expanding herself in terms of economic advancement and affluence not only in the region but as well on world scenario. China is very much engaged in Central Asia to magnify its strategic and economic power to preserve its interest. Regionalism is the process of integration, geographical relationship, formation of interstate coalition mutual interdependence of the states on the basis of regions. The key ingredients of regionalism are unilateralism, multilateralism and international trading system. The main idea of regionalism is to economically and politically integrate states on regional identification. The SCO (Shanghai Cooperation Organization) is also turning itself into regionalism. Eurasia has abundant energy resources. The exploitation and transportation of these energy resources to the rest of the world has become major challenge due to the deteriorating security situation and unrest of the region. SCO is a powerful regional mechanism which can play significant role in improving security of the region. Regionalism theoretical interpretations can be glimpsed on Central Asia, East Asia and South Asia in terms of economic, energy and security integration. The Mahan, A. Thayer in his book "The influence of sea power upon history 1660-1783" has concluded that naval strategy and power is a noteworthy factor for the rise of British Empire. The determinants of sea power are economy, population, political will of government and number of coastline and harbors available for sea trade traffic. The ongoing development project of Gwadr by China has proclivity to cater not only Chinese trade through CPEC but also have capacity to provide landlocked Central Asia access to hot water port for energy exports. Originality / Value: This paper is an original research work. The analysis provided is based on facts from various national and international publications. [ABSTRACT FROM AUTHOR]

Marine sediments serve as a sink for contaminants of anthropogenic origin. Here, 25 major and trace elements were determined in surface and core sediments from an urban lagoon (Yundang Lagoon), China. The median concentrations of Pb, Cd, Cu, and Zn in both surface and core sediments exceeded global and crustal averages. Principal component analysis for the elements and ecological impact of the heavy metals indicated spatial heterogeneity in core sediments from different lagoon areas; however, no such pattern was observed in surface sediments. Geodetector analysis indicated spatial locations of lakes, pH, N%, C%, and S% as the major factors influencing the heterogeneity of potential ecological risk index, a cumulative measure of the ecological impact of heavy metal. The interaction detector indicated nonlinear and bivariate enhancement between different physicochemical parameters. Besides, a depth profile of the elements in different samples was also elucidated. [Display omitted] • Anthropogenic activities cause the metal pollution in Yundang Lagoon. • Major and trace elements were higher at surface sediments compare to the core sediments. • PCA indicated spatial heterogeneity in the distribution of metalloids. • Risk assessment indices indicated moderate to extreme contamination by heavy metals. • Geodetector analysis indicated association of potential environmental risks of metals with sediment variables. [ABSTRACT FROM AUTHOR]

• Lagoon sediments had higher ARG pollution levels as compared to pristine sediments. • Heavy metals posed indirect negative effects on the lagoon sediment ARG profiles. • Horizontal gene transfer determined the absolute abundance of sediment ARGs. • Vertical gene transfer affected the composition of sediment ARG communities. • Deterministic and stochastic processes drove sediment ARG community assembly. Rapid urbanization has resulted in pervasive occurrence of antibiotic resistance genes (ARGs) in urban aquatic ecosystems. However, limited information is available concerning the ARG profiles and the forces responsible for their assembly in urban landscape lagoon systems. Here, we employed high-throughput quantitative PCR (HT-qPCR) to characterize the spatial variations of ARGs in surface and core sediments of Yundang Lagoon, China. The results indicated that the average richness and absolute abundance of ARGs were 11 and 53 times higher in the lagoon sediments as compared to pristine reference Tibetan lake sediments, highlighting the role of anthropogenic activities in ARG pollution. Co-occurrence network analysis indicated that various anaerobic prokaryotic genera belonging to Alpha-, Deltaproteobacteria, Bacteroidetes, Euryarchaeota, Firmicutes and Synergistetes were the potential hosts of ARGs. The partial least squares-path modeling (PLS-PM) analysis revealed positive and negative indirect effects of physicochemical factors and heavy metals on the lagoon ARG profiles, via biotic factors, respectively. The horizontal (mediated by mobile genetic elements) and vertical (mediated by prokaryotic communities) gene transfer may directly contribute the most to drive the abundance and composition of ARGs, respectively. Furthermore, the neutral community model demonstrated that the assembly of sediment ARG communities was jointly governed by deterministic and stochastic processes. Overall, this study provides novel insights into the diversity and distribution of ARGs in the benthic habitat of urban lagoon systems and underlying mechanisms for the spread and proliferation of ARGs. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Wastewater treatment plants (WWTPs) rely mainly on the microbial assemblages to contribute significantly for the removal of organic pollutants and nutrients. However, limited information is available on the ecological driving forces underlying the turnover of prokaryotic communities across wastewater treatment processes (i.e., from influents (IFs) and effluents (EFs)) within WWTPs. Here, we used a combination of the 16S rRNA gene amplicon sequencing and a quantitative ecological null model analysis to explore the ecological processes governing the turnover of the prokaryotic communities and the dominant taxonomic taxa across wastewater treatment processes of five full-scale WWTPs in China. Our results indicated that a significant variation in the composition of prokaryotic communities and the dominant taxa between IFs and EFs. The analysis of the environmental sources of indicator OTUs showed that a relatively lower abundance of the sludge/sewage and human guts associated OTUs in EFs than in IFs. Ecological null models revealed that among the ecological processes, deterministic processes were dominant in controlling the turnover of the overall communities from IFs to EFs, whereas the relative importance of deterministic processes varied among the dominant taxa (i.e., Bacteroidetes > Proteobacteria > Gammaproteobacteria > Firmicutes > Betaproteobacteria). However, the assembly of IF and EF communities was influenced mainly by the deterministic and stochastic processes, respectively. In addition, our results indicated that EF communities have a higher phylogenetic diversity than those of the IF communities, but the abundance of prokaryotic 16S rRNA genes was lower in EFs than in IFs. Overall, our study provides a novel insight of the assembly mechanisms underlying the turnover of prokaryotic communities during wastewater treatment processes. [ABSTRACT FROM AUTHOR]

Increased urbanization and anthropogenic activities can alter dissolved organic matter (DOM) and complicate its interaction with bacteria in rivers' ecosystems, however, there is limited information about how bacterial communities respond to DOM components in rivers with different urbanization levels. Here, we combined spectroscopy-based DOM analysis and 16S rRNA gene amplicon sequencing to investigate the associations of bacterial taxa and DOM properties as well as the impacts of DOM on bacterial niche breadth in North River (NR) and West River (WR) of Jiulong River watershed, southern China, which had low and high urbanization levels, respectively. Spectroscopy analysis showed that hydrophilic DOM was predominant in both rivers whereas chromophoric DOM was higher in WR. Network analysis indicated that only seven bacterial genera (i.e., hg clade , chthoniobacter , Geobacter, Acidibacter , Alphal Cluster , Fluviicola , and Lacunisphaera) showed strong associations with DOM optical variables in both rivers, whereas more than 85% of DOM-bacterial genera associations were different between rivers. These results suggest that the relationship between DOM and bacterial communities had different responses in rivers with different urbanization levels. The partial least square path model indicated that the total standardized effect of physico-chemicals on bacterial niche breadth was higher in NR (0.62) than in WR (0.35), whereas humic substances showed an opposite pattern (NR: −0.42; WR: 1.67). The distinct effects of physico-chemicals and DOM on bacterial niche breadths between rivers could be due to the different effects of urbanization and human activities on the environmental conditions of riverine ecosystems. Our findings revealed a huge dissimilarity in the bacteria-DOM co-occurrence networks between rivers with different urbanization levels and provide a novel insight that urbanization may enhance DOM's importance to bacterial niche breadths. [Display omitted] • > 85% of bacteria and dissolved organic matter (DOM) associations differed between NR and WR. • Chromophore DOM concentration and component fluorescence influenced bacterial richness. • Physico-chemicals posed different effects on bacterial niche breadth between NR and WR. • DOM had a higher effect on bacterial niche breadth in WR than that of physico-chemicals. [ABSTRACT FROM AUTHOR]

Dissolved organic matter (DOM), known as a key to the aquatic carbon cycle, is influenced by abiotic and biotic factors. However, the compositional variation and these factors' effects on fluorescence DOM (FDOM) in urban rivers undergoing different anthropogenic pressure are poorly investigated. Herein, using fluorescence excitation-emission matrix and parallel factor analysis (EEM-PARAFAC), four FDOM components (C1, C2, C3, and C4) were identified in a less urbanized north river (NR) and a more urbanized west river (WR) of Jiulong River Watershed in Fujian province, China. C1, C2, and C4 were related to humic-like substances (HLS) and C3 to protein-like substances (PLS). HLS (63.9% in WR and 36.4% in NR) and PLS (62.7% in WR and 37.3% in NR) exhibited higher fluorescence in the more urbanized river. We also found higher PLS in winter, but higher HLS in summer for both rivers. Although the coefficient of variation indicated a difference in FDOM components stability to some extent between the two rivers, the typhoon event that occurred in summer had a stronger disruptive impact on the CDOM and FDOM of a more urbanized river than that of a less urbanized river. We explore abiotic and biotic factors' effects on FDOM using the partial least squares path model (PLS-PM). PLS-PM results revealed higher significant influences of biotic factors on FDOM in the more urbanized river. This study enhances our understanding of FDOM dynamics of rivers with different anthropogenic pressure together with the abiotic and biotic factors driving them. [Display omitted] • The degree of urbanization drives the concentration of chromophoric dissolved organic matter. • Protein-like fluorescence intensity (F max) was higher in winter and higher in the more urbanized river. • F max of component 3 (i.e., Peaks = 280/332 nm) could suggest the degree of anthropogenic influences. • Typhoon event had a stronger disruptive impact on DOM of a more urbanized river. • The effects of biotic factors were higher in the more urbanized river. [ABSTRACT FROM AUTHOR]

• Sewage treatment plants and swine manure were the main pollution sources of ARGs. • ARG communities showed high degrees of invariance at the watershed scale. • Homogeneous selection determined the spatio-temporal assembly of ARGs. • Grassland and non-antibiotic micropollutants may influence the distribution of ARGs. Rivers are a significant reservoir of antibiotic resistance genes (ARGs), yet the biogeographic pattern of riverine ARGs and its underlying driving forces remain poorly understood. Here, we used metagenomic approach to investigate the spatio-temporal variation of ARGs in two adjacent sub-watersheds viz. North River (NR) and West River (WR), China. The results demonstrated that Bacitracin (22.8 % of the total ARGs), multidrug (20.7 %), sulfonamide (15.2 %) and tetracycline (10.9 %) were the dominant ARG types. SourceTracker analysis indicated that sewage treatment plants as the main source of ARGs, while animal feces mainly contributed in spreading the ARGs in the upstream of NR. Random forest and network analyses confirmed that NR was under the influence of fecal pollution. PCoA analysis demonstrated that the composition of ARGs changed along with the anthropogenic gradients, while the Raup–Crick null model showed that homogenizing selection mediated by class 1 integron intI1 resulted in stable ARG communities at whole watershed scale. Structural equation models revealed that microbial community, grassland and several non-antibiotic micropollutants may also play certain roles in influencing the distribution of ARGs. Overall, the observed deterministic formation of ARGs in riverine systems calls effective management strategies to mitigate the risks of antibiotic resistance on public health. [ABSTRACT FROM AUTHOR]