Rapid urban expansion impacts freshwater ecosystems globally and accelerates invasion of non-native fishes while related ecological processes and mechanisms are still not clear. The processes shaping the distribution and composition of native and non-native fish assemblages were explored through a four-year study in highly urbanized rivers in Shenzhen in southern China. We collected data for fish abundance in local assemblages and used the Joint Species Distribution Model (JSDM) to investigate key driving factors influencing fish distributions. We found that water quality was the main factor affecting the distribution and abundance of native fishes, whereas spatial random effects and land use explained more than half of the variance for non-native fishes. We also analyzed species distribution and abundance in relation to phylogeny and functional traits associated with morphology, life history and physiology. Greater levels of urbanization were associated with larger body length, longevity, fecundity and pectoral fin size. Phylogenetic niche conservatism was a dominant pattern in the dataset. Positive correlations among non-native fish species suggests that these urban rivers may be undergoing an “invasional meltdown”. Overall, our findings demonstrate that urban rivers can act as environmental filters that exclude sensitive native fish while facilitating the establishment and dominance of tolerant non-native species. These insights point to practical interventions: improving water quality, managing land use and limiting dispersal pathways may help mitigate native fish loss and reduce non-native dominance in urban river systems.

As the largest inter-basin water diversion project in eastern China, the Eastern Route of China’s South-to-North Water Diversion Project (ER-SNWDP) plays a crucial role in alleviating water shortages and ensuring regional ecological security. However, large-scale water diversion that uses natural lakes as impounded lakes across different basins has impacted on the structure and function of the original ecosystems. To explore the changes in the food web and ecosystem structure of the impounded lakes during different operation periods of the ER-SNWDP, we constructed Ecopath models for Hongze Lake in 2010–2011 (pre-operation), 2017–2018 (initial operation), and 2023–2024 (operational period). Our results showed that the trophic energy flow in Hongze Lake was dominated by the detrital food chain, with the highest trophic level ranging from 3.06 to 3.50. Energy flows at trophic levels I and II accounted for a high proportion of the total throughput, and the interactions between trophic levels were relatively simple, indicating that Hongze Lake is approaching a mature ecosystem. Compared with the pre-operation period, the average trophic level, food chain length, and energy conversion efficiency of Hongze Lake declined during the initial operation period, but rebounded during the operational period, though still remaining lower than the pre-operation period. Ecosystem stability followed a similar trajectory: the total primary production/total respiration (TPP/TR) and the system omnivory index (SOI) indicated that ecosystem maturity decreased during the initial operation and increased during the operational period. Fishing activities had negative effects on most functional groups during the pre-operation and initial operation periods, whereas the negative effects from zooplankton and non-native species groups increased during the operational period. Based on changes in the food web structure and ecosystem of Hongze Lake across different water diversion periods, we suggest that the management of Hongze Lake should establish precautionary fishing management measures targeting the effects of filter-feeding functional groups and non-native species, optimize the species and quantities of restocking initiatives, prioritize the protection of critical habitat integrity, and implement long-term ecological monitoring.

Fish stock serves as the foundation for fishery development and ecosystem stability.The Hainan Island,encompassing mangroves,coral reefs,estuaries,and upwelling systems,has rich diversity and distinct characteristics of fish communities in the nearshore waters of the island.To comprehensively clarify the spatiotemporal dynamics of fish community characteristics in nearshore waters of Hainan Island and systematically analyze the variations of species composition,dominant taxa,and resource abundance among different regions,we conducted two bottom trawl surveys in August and November 2024,corresponding to the southwest and northeast monsoon seasons respectively,and used a combination of statistical methods,including one-way analysis of variance,permutational multivariate analysis of variance,and principal coordinates analysis to analysis the variations of fish communities in different regions in nearshore waters of the island.The results showed that 451 species of fish were collected,dominated by resident and warm-water fish;the eastern Sanya-Lingshui waters had the highest number of species(228 species),whereas the Mulantou waters had the fewest number of species(116 species).The number of species in November was higher than that in August,and 223 species were the most common in both surveys.Sørensen's dissimilarity index divides the composition of fish in nearshore waters of Hainan Island into the southeastern(Wenchang,Qionghai-Wanning,and Lingshui-Qiongsanya waters),western(Ledong,Changjiang-Dongfang and Danzhou-Linggao waters),and northern(Qionghzhou Straits and Mulantou waters)zones.The highest abundance of fish stock was in the western Changjiang-Ledong Sea(22,036 ind./km2,536.8 kg/km2)and eastern Qionghai-Sanya Sea(18,656.9 ind./km2,383.4 kg/km2;P＜0.05),which overlapped with the coastal upwelling area.The abundance of fish in August(after the seasonal moratorium on fishing)(mean 23727.4 ind./km2,473.7 kg/km2)was significantly greater than that in November(mean 12,299.6 ind./km2,289.7 kg/km2;P＜0.001).The dominant species were small and low-value species,such as Saurida undosquamis,Terapon theraps,Thamnaconus hypargyreus,and Johnius grypotus.The composition of the dominant species varied among different waters in nearshore waters of Hainan Island;the dominant species included J.grypotus,Setipinna tenuifilis,and Cynoglossus macrolepidotus in northern waters,S.undosquamis,Saurida tumbil,Upeneus japonicus,and Champsodon snyderi in southern waters,and T.theraps,Pennahia macrocephalus,and J.grypotus in western waters.The similarity of the fish community in the southeastern waters of the nearshore waters of Hainan Island was distinguished from that in the western waters,and the fish communities in the northern waters were characterized by the transition between the southeastern and western waters.S.undosquamis,U.japonicus,T.hypargyreus,J.grypotus,T.theraps,and Brachypleura novaezeelandiae were the dominant species contributing to the differences of fish communities between the southeastern and western waters in nearshore waters of Hainan Island.Our study showed that fish communities in the nearshore waters of Hainan Island have clear spatial and temporal characteristics,which are consistent with the geographical environment characteristics around the island.Fish communities in the western waters of the island are mainly composed of non-rock reef bottom-dwelling species.These waters are located in the semi-enclosed bay of Beibu Gulf,which is driven by wind currents and has a sandy mud composition.In the southeastern waters,the dominant groups are shelf-rocky and reef fishes,and the waters are mainly influenced by the South China Sea Warm Current and upwelling.The trends of declining fish diversity,decreasing abundance,and increasing proportion of small fish were still evident in the nearshore waters of Hainan Island.Therefore,it is suggested that(1)Fundamental research on fish stock in the inshore waters of Hainan should be enhanced,and it necessary to clarify the mechanisms of fishery resource changes,diversity maintenance,and resource replenishment.(2)Catchable resources and fishing intensity in different areas in nearshore waters of Hainan Island should be reasonably planned,and fishing quota system and marine ecological compensation measures should be promoted.(3)Typical habitats such as mangroves,coral reefs,and seagrass beds should be primarily protected and restored to ensure the replenishment of fish stocks.(4)The system of permitted fishing gear and minimum mesh size should be strictly implemented to alleviate the pressure of non-selective fishing.(5)A standardized landing system for catches and socialized catches supervision system should be established to encourage broader people to participate in the protection of fishery resources.

Fish functional response to conservation measures such as fishing bans is very important for lake biodiversity conservation but remains less studied. We conducted a 6-year fish community investigation in Luoma Lake of the Huai River Basin in China, including three years (2018–2020) before and three years (2021–2023) after a full fishing ban (i.e., complete removal of fishing pressure). Taxonomic and functional diversity indices, including species richness, Shannon and Simpson diversity index, Pielou’s evenness, functional richness (FRic), functional evenness (FEve), and functional dispersion (FDis), were used to assess community-level changes. Community-weighted mean (CWM) values were calculated from 12 functional traits, and R-mode linked to Q-mode (RLQ) analysis combined with the fourth-corner test was conducted to link traits to environmental gradients. We found no significant change in fish abundance and taxonomic diversity, but fish biomass and functional richness increased significantly after the fishing ban. Non-metric multidimensional scaling (NMDS) and similarity percentage (SIMPER) analysis indicated that the fish community underwent significant compositional changes following the fishing ban. Trait–environment analysis showed that age at first maturity, mouth position, body shape, feeding habit, and life history strategy were significantly associated with environmental gradients. These results suggest that the fishing ban promoted early functional recovery and ecological reorganization processes of the fish community, highlighting the functional mechanisms underlying assemblage restructuring.

The North Creek Basin of the Jiulong River is located in a typical subtropical monsoon climate zone, characterized by distinct hydrological seasonality. However, systematic research on the temporal and spatial variations of its fish community structure and the underlying driving mechanisms remains lacking. To understand spatiotemporal patterns of fish communities and the driving factors in the North Creek Basin of the Jiulong River, we examined fish communities from 18 sampling sites in March (spring, the dry season) and September (autumn, the wet season) of 2021. A total of 58 fish species, belonging to 49 genera, 16 families and 4 orders, were collected throughout the year. The majority of the specimens were cyprinids, followed by flathead loaches and gobies. The dominant species in the dry season included Coptodon zillii, Rhinogobius giurinus, and Oreochromis niloticus. The dominant species were C. zillii and O. niloticus in the wet season. Species richness and Shannon index were significantly lower in the dry season than those in the wet season. Spatially, fish abundance in the mainstem was significantly lower than that in the tributaries. Redundancy analysis results indicated that water depth and dissolved oxygen were the key environmental factors influencing fish abundance and biomass patterns during the dry season. During the wet season, water temperature, dissolved oxygen, and permanganate index were the key factors affecting fish abundance and biomass patterns. This study revealed the spatiotemporal patterns and influencing factors of fish communities in the North Creek Basin, providing a scientific basis for fish diversity conservation and ecosystem health maintenance in subtropical rivers.

Heavy metals in freshwater lakes under inter-basin water diversions may pose harms to lake ecosystems and human health but have rarely been studied. We studied fish heavy metals in water diversion lakes, Gao-Bao-Shaobo Lakes (GBSLs), along the South-to-North Water Diversion Project in China, and evaluated associated human health risks from fish consumption. A total of 322 muscle samples from 29 fish species were collected to characterize contamination patterns of copper (Cu), chromium (Cr), cadmium (Cd), lead (Pb), and arsenic (As). The studied heavy metals in fish were found within China's food safety standards. Among the studied metals, Cu, Cd, Pb, and As had higher concentrations temporally in autumn and spatially in Gaoyou Lake. Moreover, Cd, Pb, and As in carnivores were significantly higher than other feeding groups, and Cd and As in upper-middle and upper water layers were significantly higher than other layers. Consumption of GBSLs fish did not pose a non-carcinogenic risk to human health. However, consumption of fish species such as Protosalanx hyalocranius, Carassius auratus, Culter alburnus may pose potential carcinogenic risks to human health due to Cr and Cd. The current study had implications for assessing aquatic ecological conditions and reducing human dietary health risks related to heavy metals in water diversion lakes.

Habitat is less studied in subtropical rivers under rapid basin human development. We assessed river habitat quality (RHQ) in both urbanized and forested river basins in Shenzhen, the rapidly urbanized region with the fastest economic development in China. RHQ assessments were conducted in both wet (August) and dry (November) seasons of 2019 from a total of 61 sites: Maozhou River (urbanized, n = 11), Guanlan River (urbanized, n = 13), Shenzhen River (urbanized, n = 13), Pingshan River (forested, n = 12) and Dapeng Bay River (forested, n = 12). We used generalized additive models to detect relationships between urban intensity and RHQ, and principal components analysis to identify key indicators influencing RHQ. We found that scores of overall RHQ and most habitat indicators were significantly lower in urbanized basins than those in forested basins. Human activity intensity, vegetation diversity and riparian land use patterns were identified as key indicators affecting RHQ. Urban intensity had significantly negative relationships with overall RHQ and many of its indicators. This study enhances our understanding of the impacts of urbanization on river habitat, which has implications for the rehabilitation of subtropical rivers affected by urbanization.

The cotton rat (Sigmodon hispidus) has emerged as a preclinical model for human respiratory syncytial virus (RSV) research because of its ability to support effective viral replication and recapitulate disease; however, the mechanisms supporting this evolutionarily conserved phenotype remain unclear. Here, we report both the chromosomal genome and respiratory single-cell transcriptomic atlas of the cotton rat throughout the course of RSV infection. Phylogenetic analysis showed that cotton rats are in different evolutionary branches from common mouse and rat models and exhibit substantial conservation of tissue profiles with humans. The respiratory cell atlas, alveolar cell trajectory, and distribution of potential viral receptors are also similar to those of humans, explaining the superiority of cotton rats as an RSV infection model. The target cells of RSV, including club cells, secretory2 cells, mesothelial cells, and nerve-associated astrocytes, were expanded after infection. We also identified differential transcriptional regulators, specific antiviral proteins, and cytokines that could be translated into potential clinical markers in humans. Candidate host factors were also identified, which will enable the exploration of host-RSV interactions and offer a source of therapeutic targets.

The African swine fever virus (ASFV) type II topoisomerase (Topo II), pP1192R, is the only known Topo II expressed by mammalian viruses and is essential for ASFV replication in the host cytoplasm. Herein, we report the structures of pP1192R in various enzymatic stages using both X-ray crystallography and single-particle cryo-electron microscopy. Our data structurally define the pP1192R-modulated DNA topology changes. By presenting the A2+-like metal ion at the pre-cleavage site, the pP1192R-DNA-m-AMSA complex structure provides support for the classical two-metal mechanism in Topo II-mediated DNA cleavage and a better explanation for nucleophile formation. The unique inhibitor selectivity of pP1192R and the difunctional mechanism of pP1192R inhibition by m-AMSA highlight the specificity of viral Topo II in the poison binding site. Altogether, this study provides the information applicable to the development of a pP1192R-targeting anti-ASFV strategy.

The global outbreak of the mpox virus (MPXV) in 2022 highlights the urgent need for safer and more accessible new-generation vaccines. Here, we used a structure-guided multi-antigen fusion strategy to design a 'two-in-one' immunogen based on the single-chain dimeric MPXV extracellular enveloped virus antigen A35 bivalently fused with the intracellular mature virus antigen M1, called DAM. DAM preserved the natural epitope configuration of both components and showed stronger A35-specific and M1-specific antibody responses and in vivo protective efficacy against vaccinia virus (VACV) compared to co-immunization strategies. The MPXV-specific neutralizing antibodies elicited by DAM were 28 times higher than those induced by live VACV vaccine. Aluminum-adjuvanted DAM vaccines protected mice from a lethal VACV challenge with a safety profile, and pilot-scale production confirmed the high yield and purity of DAM. Thus, our study provides innovative insights and an immunogen candidate for the development of alternative vaccines against MPXV and other orthopoxviruses.

Off-seasonal water level regulations disrupt the biological traits and phenological rhythms of native fish species, yet their impacts on interspecific trophic interactions remain understudied. This study employed stable isotope analysis to assess the trophic dynamics of three fish species (Parabramis pekinensis, Carassius auratus, and Toxabramis swinhonis) across different water periods in Hongze Lake. The findings revealed that all three species occupied similar mid-level trophic positions, with no significant difference among water periods (p > 0.05). During high-water periods, P. pekinensis and T. swinhonis exploited broader niches, while C. auratus relied on a narrower diet. In contrast, during low-water periods, C. auratus expanded its niche, while P. pekinensis and T. swinhonis reduced their isotopic niche widths. Niche overlap analysis showed minimal trophic overlap among the three species during high-water periods, with increased overlap during low-water periods, except for the highest overlap between C. auratus and T. swinhonis during mid-water periods. This variation in niche overlap aligns with shifts in dietary reliance, as POM was the predominant dietary component for all three species, but its contribution varied significantly across different water periods. These findings indicated that adaptive trophic niche facilitated the coexistence of these fish species, while off-seasonal water level regulation may intensify interspecific competition. These insights are essential for refining water management policies and developing sustainable fishery management strategies of Hongze Lake and other water-level-regulated systems.

The recent outbreak of mpox epidemic, caused by monkeypox virus (MPXV), poses a new threat to global public health. Here, we initially assessed the preexisting antibody level to the MPXV B6 protein in vaccinia vaccinees born before the end of the immunization program and then identified two monoclonal antibodies (MAbs), hMB621 and hMB668, targeting distinct epitopes on B6, from one vaccinee. Binding assays demonstrate that both MAbs exhibit broad binding abilities to B6 and its orthologs in vaccinia (VACV), variola (VARV) and cowpox viruses (CPXV). Neutralizing assays reveal that the two MAbs showed potent neutralization against VACV. Animal experiments using a BALB/c female mouse model indicate that the two MAbs showed effective protection against VACV via intraperitoneal injection. Additionally, we determined the complex structure of B6 and hMB668, revealing the structural feature of B6 and the epitope of hMB668. Collectively, our study provides two promising antibody candidates for the treatment of orthopoxvirus infections, including mpox.

为探讨湖泊内部阻隔引发的生态问题,阐释鱼类群落聚合对湖泊内部阻隔的响应,研究选取长江中游典型阻隔湖泊保安湖为研究对象,于2019-2020年夏季和秋季对其肖四海湖区(完全阻隔)、扁担塘湖区(半阻隔)、桥墩湖区(半阻隔)和主体湖区的鱼类群落结构进行了调查,应用单因素方差分析、置换多元方差分析和非度量多维尺度等多重统计方法分析了湖区间鱼类群落组成和多样性的差异.结果表明,完全阻隔湖区肖四海鱼类群落结构发生了明显变化,其种类数[(15±3)种]显著低于半阻隔湖区[(22±3)种]和主体湖区[(23±3)种,P<0.05],鱼类丰度高而生物量低,物种丰富度指数、Shannon指数和Simpson指数显著低于主体湖区(P<0.05),功能丰富度指数、功能分散度指数和功能均匀度指数也显著较低(P<0.05);而半阻隔湖区鱼类群落结构与主体湖区无显著性差异.置换多元方差分析和非度量多维尺度分析也显示出完全阻隔湖区鱼类群落与半阻隔湖区和主体湖区鱼类群落具有显著性差异(P<0.05),半阻隔湖区与主体湖区无显著性差异.研究发现湖泊内部水文阻隔对鱼类群落组成也有着重要影响,恢复湖泊内部水文自由连通对湖泊生态管理和生物多样性保护有着重要作用.

Many severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)-related coronaviruses have been discovered,constituting potential threats to human health.However,it remains unclear whether the currently available vaccines are effective against these coronaviruses.Here,we constructed a wild-type mouse model to evaluate pathogenicity of the SARS-CoV-2-related pangolin coronavirus GX/P2V/2017 and neutralization efficacy of the approved tandem-repeat SARS-CoV-2 spike receptor-binding domain(RBD)vaccine ZF2001.We found that ZF2001-induced cross-reac-tive and cross-neutralizing antibodies against GX/P2V/2017,and the vaccination alleviated the pathological lung damage caused by GX/P2V/2017 in mice.These results indicate that RBD may work as a promising candidate for pan-coronavirus vaccine development.

Understanding patterns and driving factors of freshwater fish biodiversity in metacommunities is essential for biological conservation but rarely studied in regions experiencing rapid land use changes. We examined changes of both alpha and beta fish diversities in taxonomic, functional, and phylogenetic facets during the 1980 s to 2010 s, and quantified contributions from natural and human drivers in lakes located in China's fastest economic development region. Results showed that almost all indices of alpha and beta diversity decreased through time. For alpha diversity, taxonomic and functional richness declined by 13 to 15%. Rheophilic and piscivorous fish species declined by 50 and 36%, respectively. For beta diversity, the decline of overall functional (-31%) diversity was greater than taxonomic (-17%) and phylogenetic (-19%) diversity. The decline of multiple facets of beta diversity indicated that fish communities in these lakes have homogenized through time. Land use (i.e., increased urban land and aquaculture ponds), hydrology (i.e., increased water level), climate (i.e., increased air temperature), and fishing (i.e., increased lake fishery catch) factors all made significant contributions to both alpha and beta fish diversity decline in multiple facets. The overall contribution from land use to the decline of multidimensional fish diversity was greater than those of other stressors. While attention should be given to both local human disturbance and regional climate factors, in regions experiencing rapid economic development and land use changes, local disturbances should be considered as a priority in biodiversity management plans.

Thiamine (vitamin B-1) and its precursor 2-methyl-4-amino-5-hydroxymethylpyrimidine (HMP) have been shown to exert an important influence on primary production in marine environments, but little is known about their influence in fresh waters. We evaluated the ecological effects of thiamine and one of its precursors HMP in streams within the Qiyun catchment, a headwater mountain system of a Yangtze River tributary in Southern China, using nutrient-diffusing substrates. Thiamine limitation of periphyton was observed in April 2019, and HMP limitation was observed in both April and May 2019. Co-limitation by thiamine plus phosphorus and by HMP plus nitrogen occurred in May. The effect sizes of thiamine and HMP on growth of periphyton were similar to each other. Physiochemical features of the stream showed different potential influences on the effects of thiamine and HMP. Water temperature was negatively associated with the effect of thiamine, whereas ammonium showed a negative relationship with the effect of HMP. These findings extend our knowledge of nutrient limitation by thiamine and one thiamine precursor in freshwater environments.

Background The application of index of biotic integrity (IBI) to evaluate river health can be an essential method for river ecosystem management. However, these types of methods were developed in small, low-order streams, and are therefore, infrequently applied to large rivers. To that end, phytoplankton communities and environmental variables were monitored in 30 sampling segments of the middle and lower reaches of the Yangtze River, China during the wet (July–August) and dry (November–December) seasons in 2017–2018. We developed a phytoplankton-based index of biotic integrity (P-IBI) and used the index to assess the ecological health of the Yangtze River. Relationships among P-IBI, its component metrics, and environmental factors were analyzed across different seasons. Results Results obtained from the P-IBI indicated that the phytoplankton-based ecological health of the Yangtze River was rated as “good” during both seasons, with an overall better condition in the dry season. During the wet season, there were scattered river segments with P-IBI ratings of “fair” or below. Water quality and land use appeared to shape the patterns of P-IBI. In the wet season, P-IBI negatively correlated with total phosphorus, nitrate, total suspended solids, turbidity, conductivity, and dissolved oxygen. In the dry season, P-IBI positively correlated with total nitrogen, ammonium, and nitrite, and negatively correlated with water temperature. Conclusions The ecological health of the Yangtze River as reflected by the P-IBI exhibited spatial and temporal variability, with the effect of water quality being greater than that of local land use. This study indicated the importance of considering seasonal effects in detecting large river ecological health. These findings enhanced our understanding of the ecological health and characterized potential benchmarks for management of the Yangtze River. These findings also may be applicable to other large rivers elsewhere.

Understanding contributions of different environmental drivers to the structure and function of river biota is critical for biodiversity and environmental conservation. Yet, there is no consensus on which drivers have the greatest impact on fish diversity, especially in watersheds disturbed by multiple human activities. Fish taxonomic, phylogenetic, and functional diversity at both alpha and beta dimensions and their environmental drivers were studied in a total of 84 river sites from three watersheds, Huai River watershed (HRW), Sui River watershed (SRW), and Yishusi River watershed (YRW) in the Eastern Huai River Basin of China. Results showed that rivers in the three watersheds had no significant difference in both taxonomic and functional alpha diversity. Rivers in the HRW had significantly higher phylogenetic alpha diversity. For taxonomic and phylogenetic beta diversity, the overall beta diversity and turnover component were significant higher in the HRW. For functional beta diversity, the overall beta diversity was significantly lower in the HRW. Multiple linear regression (MLR) and redundancy analysis (RDA) showed that local (e.g., nutrients, dissolved oxygen, river width, transparency), regional (e.g., wetland), climate (e.g., temperature), and spatial variables structured alpha and beta fish diversity. Variation partitioning analysis indicated that the pure contributions of local and spatial variables were more important than that of climate and regional variables, which suggested that spatial effects and local environmental filtering were the main factors driving the beta diversity of fish assemblages in these rivers. The current study highlights the importance of considering multidimensional diversity and multiple environmental factors for conserving river fishes.

Urbanization is considered as a major cause of widespread biodiversity loss in freshwater ecosystems. However, multidimensional fish diversity patterns driven by urbanization in subtropical rivers are still unclear. We studied fish taxonomic, functional, and phylogenetic diversity in rivers under a gradient of watershed urbanization (Maozhouhe, Guanlanhe and Shenzhenhe rivers are in urbanized watersheds while Pingshanhe and Dapengwan rivers are in forested watersheds) in Shenzhen, a megacity with rapid urbanization in south China. Fish assemblages showed significant differences between the forested and urbanized watersheds in both the wet and dry seasons. Rivers in the forest watersheds showed significantly higher taxonomic and functional but lower phylogenetic diversity patterns. Rivers in the urbanized watersheds were largely occupied by non-native species. Overall, there was a distinct difference in river fish assemblages between forested and urbanized watersheds, and urbanization largely affected multidimensional fish diversity. These results will help us to take more effective conservation and restoration measures, and provide an essential reference for ecological management and sustainability of urban rivers.