Qiuwen Chen

Nanjing Hydraulic Research Institute | NHRI · Center for Eco-Environmental Research

Motivation: Freshwater ecosystems have been heavily impacted by land-use changes, but syntheses on the impacts on freshwater ecosystems are still limited. Here, we compiled a global database encompassing 248 studies with species abundance data (from multiple taxon groups and geographic locations) across sites with different land-use categories. Thi...

The establishment of reservoirs, which alter water temperature and flow dynamics, significantly affects the indigenous fish population, yet the underlying molecular mechanisms remain unclear. To investigate effects of the changing water temperature and flow rate on fish ovaries, we subjected female Coreius guichenoti to the combination of different...

The addition of crop straw is considered an important measure for sustainable agricultural production. Crop straw when incorporated into the soil affects crop growth and development by changing the hydrothermal conditions of the soil. However, quantitative studies that inform on the mechanisms by which added straw or straw biochar (SSB) affects hyd...

There are different phosphorus (P) sources of varied concentrations in aquatic ecosystems. The sensing of P by cyanobacteria in the environment is predominantly regulated by two-component signal transduction systems in which the phosphate (Pho) regulon plays a crucial role in maintaining phosphate homeostasis. It responds rapidly and connects to me...

Reservoir drawdown areas (DAs) can be both important nitrogen (N) sources to river networks and hot spots for N removal from freshwater ecosystems. The net effect of DAs on the N availability in reservoirs within a full hydrological cycle remains unclear. In this paper, the N dynamics in the DA of the Three Gorges Reservoir, Yangtze River, China, a...

Identifying the factors and quantifying their contributions to nitrogen (N) loss associated with surface runoff is of great significance to the control of non‐point source N pollution. However, the distinct geographical units, such as hills and plains, may lead to great differences in the contribution of these driving factors, which has been rarely...

Understanding streamflow change and its ecological impacts under climate change and land use/cover change (LUCC) makes possible the improvement of water and ecological governance decision-making. Gaining a comprehensive understanding of the drivers of historical streamflow changes can provide valuable insights for effective projections of future st...

The severe impacts of river damming on fish habitats have aroused widespread attention, prompting major conservation measures to help mitigate these negative effects.

The extensive utilization of Zinc Oxide nanoparticles (ZnO NPs) has garnered significant attention due to their detrimental impacts on ecosystem. Unfortunately, ecotoxicity of ZnO NPs in coastal waters with fluctuating salinity has been disregarded. This study mainly discussed the toxic effects of ZnO NPs on species inhabiting the transition zones...

The algal blooms have become a long-term challenge for global water ecology and environment. Changes in wind conditions and hydraulic scheduling of water diversion projects can change the hydrodynamic structure of the lake, affecting the growth and aggregation process of algae. Fine monitoring and mechanism analysis of this process are important fo...

Conserving the quality of transferred water ensures the success and sustainability of interbasin water diversion works, which are increasingly crucial for global water security. Despite intensive scientific and engineering efforts, carbon dynamics in these artificial rivers have been overlooked. The accumulation of organic mud in some water transfe...

River damming has brought great benefits to flood mitigation, energy and food production, and will continue to play a significant role in global energy supply, particularly in Asia, Africa, and South America. However, dams have extensively altered global river dynamics, including riverine connectivity, hydrological, thermal, sediment and solute reg...

Increasing algal blooms in freshwater lakes have become a serious challenge facing the world. Short-term forecast of chlorophyll-a concentration (Chla) is essential for providing early warnings and taking action to mitigate the risks of algal blooms in freshwater lakes. At present, a variety of data-driven models and physical-based models have been...

Flow and water surface elevation recession rate Regulated and unregulated flows Dam operation A B S T R A C T Fish can be stranded in pools during flow recessions that may occur naturally or as a result of dam operations. Past studies have recommended dam operation guidelines that only consider water surface elevation (WSE) recession rate to reduce...

Climate change has remarkable effects on the hydrological regime in floodplain wetlands. However, the hydrodynamic simulation under climate change conditions suffers from the uncertainty of the downstream water level boundary. In this study, an effective approach was developed by integrating an advanced machine learning algorithm and a process-base...

Using unregulated tributaries to compensate fish habitat loss in dammed mainstreams has recently been suggested as a promising strategy for river ecological restoration. One critical prerequisite is to find potential tributaries as alternative habitat, which depends on precise fish community surveys. In this study, both eDNA metabarcoding and elect...

Exploring the response between benthic community changes and environmental variables has significance for restoring the health of river ecosystems. However, little is known of the impact on communities of interactions between multiple environmental factors, and frequent changes in the flow of mountain rivers are different from those in the flow of...

It is typical to use a single portion of the available data to calibrate hydrological models, and the remainder for model evaluation. To minimize model‐bias, this partitioning must be performed so as to ensure distributional representativeness and mutual consistency. However, failure to account for data sampling variability (DSV) in the underlying...

ZnO nanoparticles (ZnO NPs) have been applied in a wide range of fields due to their unique properties. However, their ecotoxicological threats are reorganized after being discharged. Their toxic effect on anadromous fish could be complicated due to the salinity fluctuations during migration between freshwater and brackish water. In this study, the...

Land use and land cover (LULC) have significant impacts on river water quality, particularly in regions subjected to rapid urbanization. However, it is unclear whether LULC (LULC type and pattern index) can be used as an effective indicator to predict water quality over the rapid urbanization regions. Here, we investigated the spatiotemporal change...

Field investigation indicated that the reduction in fish spawning was associated with the alteration in water temperatures, even a 2–3 °C monthly difference due to reservoir operations. However, the physiological mechanism that influences the development of fish ovary (DFO) remains unclear. Thus, experiments of Coreius guichenoti were conducted at...

Hydraulic connectivity has great effects on water quality. Enclosure aquaculture can largely alter lake flow regime and thus deteriorate water quality. Understanding the dynamics and influencing factors of water quality in enclosure aquaculture lakes is of great significance to ecosystem restoration of degraded lakes. However, it remains challengin...

Antibiotic stewardship is hindered by a lack of consideration for complicated environmental fate of antibiotics and their role in resistance development, while the current methodology of eco-toxicological risk assessment has not been fully protective against their potential to select for antibiotic resistance. To address this problem, we establishe...

Floodplains play essential roles in the ecological functions of regional environments. The merging and coalescence of bacterial communities in aquatic environments results in periodic patterns driven by regular hydrological activities, which may, in turn, influence ecological activities. However, the degree of bacterial community coalescence in the...

Climate change threatens biodiversity through global alteration of habitats, but efficient conservation responses are often hindered by imprecise downscaling of impacts. Besides thermal effects, warming also drives important ancillary environmental changes, such as when river hydrology evolves in response to climate forcing. Earlier snowmelt runoff...

Periodic flooding in floodplain wetlands dominates the landscape pattern, creating rich and diverse habitats for waterbirds. However, most studies on floodplain wetland landscape are conducted at interannual scale, while few researches investigate the effect of short‐term changes of hydrological components, such as maximum continuous flooding day,...

Cyanobacterial blooms challenge the safe water supply in estuary reservoirs. Yet, data are limited for the variation of phytoplankton dynamics during an algal bloom event at refined scales, which is essential for interpreting the formation and cessation of blooms. The present study investigated the biweekly abundances and dynamics of pico- and nano...

The livestock breeding industries face overuse of antibiotics, which has been intensively studied in recent years. However, the occurrence and fate of antibiotics as well as their potential threats to the aquatic environments in alpine and arid regions remain unclear. This study investigated the relationship of the occurrence and concentrations of...

Large water resource projects may severely alter hydrological regimes and thus the habitat conditions for biota in wetlands. Plenty of habitat models for fish, vegetation, and invertebrates have been developed and widely used; however, there is a lack of effective models to assess the effects of water resource projects on waterbird habitat in wetla...

In this paper, two trophic lakes: Lake Taihu and Lake Yanghe, and three alpine lakes: Lake Qinghai, Lake Keluke, and Lake Tuosu, were investigated to discover the connections between environmental factors and the phytoplankton community in lakes with differences in trophic levels and climatic conditions. Three seasonal data, including water quality...

Error estimation and data fusion are critical to improving the accuracy of global model- and satellite-based precipitation products for practical applications. However, they face challenges over vast areas of the world due to limited ground observations. Triple collocation (TC) method can overcome this limitation and provide an efficient way for er...

Endocrine-disrupting compounds (EDCs) enter lakes mainly through river inflow. However, the occurrence, transport and fate of EDCs in the overlying water, suspended particulate matter (SPM) and sediment of inflowing rivers remain unclear. This study investigated the load of seven EDCs in a complex river-lake system of the Taihu Lake Basin during di...

Methylmercury (MeHg) can be bioaccumulated through food chains and adversely affect human health. Reservoirs are reported to stimulate MeHg production, however, the characteristics of MeHg dynamics in cascade reservoirs and the associated relations to sedimentation as well as reservoir properties remained unclear. Here we investigated sediment MeHg...

Quantitative predictions of total dissolved gas (TDG) super-saturation are essential for developing operation schemes for high dams. Most TDG generation prediction models have various shortcomings that affect the accuracy of TDG super-saturation estimation, such as oversimplification of influencing factors and uncertainty in parameter values. In th...

China's current water quality standards (WQS) were first established in the 1980s referring the other countries' experience in setting environmental criteria and may not be suitable for the circumstances in China. Thus, it is necessary to improve the theories and methodologies of WQS. This paper provided a promising method to determine water qualit...

Dam construction is widespread, changing the hydrological and biogeochemical conditions and thereby the bacterial communities in the rivers of the earth. To date, knowledge is lacking about bacterial communities in cascade reservoirs. Here, we investigated the bacterial communities and potential functions of nine cascade hydropower reservoirs in 12...

Purpose In complex watersheds with multiple types of waterbodies, the effect of river damming on the distribution pattern of heavy metals in sediments and their potential ecological risks are inconsistent, leading to an inability to accurately manage heavy metal pollution. The aim of this study was to reveal the driving mechanisms of hydropower res...

Iron salts are increasingly employed in wastewater treatment worldwide, generating ferric phosphate sludge with low phosphorus (P) bioavailability. The fermentation of ferric phosphate sludge effectively transfers P from the solid phase to the liquid phase and simultaneously releases high contents of ferrous cations (Fe²⁺) and humic acids (HA) into...

Understanding the relation between landscape pattern and water quality is essential to making a master plan for restoration of regional lake and wetland clusters, which has not yet been well resolved. Here, we studied the impacts of landscape pattern changes on water quality over lake clusters, taking the aquaculture area in the Lixia River hinterl...

A novel multi-source data fusion method based on Bayesian inference (BIF) was proposed in this study to blend the advantages of in-situ observations and remote sensing estimations for obtaining accurate chlorophyll-a (Chla) concentration in Lake Taihu (China). Two error models (additive and multiplicative) were adopted to construct the likelihood f...

In this study, we have investigated the purification efficiency during enhanced coagulation, ozone oxidation and their combined processes for the removal of trace amounts of EDCs in different DOM matrices. The results indicated that the maximum removal efficiency of EDCs occurred at or near pH 7.0 when measured over a pH range of 4.0–10.0. The addi...

Both cyanobacterial bloom and antibiotic resistance have aggravated worldwide and posed a global threat to public health in recent years. Cyanobacteria can exhibit discrepancy between their resistance genotype and susceptible phenotype due to antibiotic heteroresistance, which leads to difficulties in unambiguously classifying cyanobacterial strain...

Flooding has been one of the major issues that have seriously hampered the developments of the urban systems, as well as threatened the urban water environments. To mitigate the impacts of floods, it is highly important to identify effective evacuation plans with the aid of computer-based methods. However, effectively identifying the dynamic evacua...

Current expectation is that projected climate change may have adverse effects on fish habitats and survival. The analysis leading to these concerns is typically done at large scale with limited possibility to quantify the local biological response and compare with previous conditions. Our research investigated the effects of recorded climate condit...

In dammed rivers, sediment accumulation creates potential methane emission hotspots, which have been extensively studied at sediments deposited on the riverbed. However, methane emissions from sediment deposited riparian zones at the land‐water interface remain poorly understood. We investigated the spatial pattern of diffusive methane emissions fr...

Cascade dams segment river connectivity, modify the hydrological process, and change the hydraulic properties, thus influencing the river ecosystem significantly. Ecological effects of dams have been extensively studied, but investigations on zoobenthos in a large area covering tributaries and mainstream with cascade dams are lacking. Here, we stud...

Toxic cyanobacteria bloom is a ubiquitous phenomenon worldwide in eutrophic lakes or reservoirs. Microcystis, is a cosmopolitan genus in cyanobacteria and exists in many different forms. Microcystis aeruginosa (M. aeruginosa) can produce microcystins (MCs) with strong liver toxicity during its growth and decomposition. Phosphorus (P) is a typical g...

Dam removal has been widely used as a river restoration approach; however, the effectiveness of removing low-head dams in tributaries for fish habitat compensation in a dammed river is still poorly understood. One major impediment to examining the ecological effectiveness of low-head dams is the short length of post-dam hydrologic, geomorphic and e...

Dam operations considerably influence water temperature regimes in rivers, which affects fish spawning activities. Previous studies have focused on the effects of critical temperature (CT) alterations during the spawning period, and largely ignored the effects of accumulated temperature (AT) alterations on gonadal development. Successful spawning r...