Seasonal co-occurrence patterns of bacteria and eukaryotic phytoplankton and the ecological response in urban aquatic ecosystem

Microorganisms play a key role in aquatic ecosystems.Recent studies show that keystone taxa in microbial community could change the community structure and function.However,most previous studies focus on abundant taxa but neglected low abundant ones.To clarify the seasonal variation of bacterial and microalgal communities and understand their synergistic adaptation to diff erent environmental factors,we studied the bacterial and eukaryotic phytoplankton communities in Fenhe River that runs through Taiyuan City,central China,and their seasonal co-occurrence patterns using 16S and 18S rDNA sequencing.Results indicate that positive interaction of eukaryotic phytoplankton network was more active than negative one except winter,indicating that the cooperation(symbiotic phenomenon in which phytoplankton are interdependent and mutually benefi cial)among them could improve the adaption of microbial community to the local environmental changes and maintain the stability of microbial network.The main genera that identifi ed as keystone taxa in bacterial network were Salinivibrio and Sphingopyxis of Proteobacteria and they could respond to the variation of nitrite and make use of it,while those that identifi ed as keystone taxa in eukaryotic phytoplankton network were Pseudoschroederia and Nannochloris,and they were more susceptible to nitrate and phosphate.Mychonastes and Cryptomonas were closely related to water temperature.However,the loss of the co-occurrence by environmental factor changes aff ected the stability of network structure.This study provided a reference for analyzing relationship between bacteria and eukaryotic phytoplankton and revealing potential importance of keystone taxa in similar ecological domains in carbon,nitrogen,and phosphorus dynamics.

Periphyton response to nitrogen and phosphorus enrichment in a eutrophic shallow aquatic ecosystem

We examined changes in biomass and species dominance of periphyton in response to nitrogen (N) and phosphorus (P) enrichment in 12 mesocosms representing eutrophic aquatic ecosystems. The 100-L mesocosms consisted of lake water and pond sediment, and N and P were applied weekly. Periphyton samples were taken to assess the biomass (as estimated by the concentration of chlorophyll a (chl a)) and to determine which species were dominant. The mean periphyton biomass (chl a) in the P-enriched treatment did not differ from that in the control group, but increased with N enrichment. Compared with that in the control group, the chl a concentration increased with N+P enrichment in the early stages of the experiment, but decreased in the later stages. The decline in periphyton biomass at the later stages of the experiment was due to limited light availability, which resulted from the increased phytoplankton density in the experiment. The nutrient enrichment treatments resulted in changes in the dominant algal species in the periphyton, suggesting that various algal species showed different responses to different nutrients. The results of this study have implications for nutrient management in aquatic ecosystems.

Kinetic Behaviour of Lanthanum in Simulated Aquatic Ecosystem

The rules of transportation and distribution of La in each component of a simulated aquatic ecosystem were studied by using tracer isotope (() (140)La.) A mathematical model was developed to simulate the behavior of La. Results show that the contents of lanthanum in each component of a simulated aquatic ecosystem are as: honewort>sediment>snail>fish. The kinetic behaviour of La in the simulated aquatic ecosystem can be described by closed-five-component models.

Current Situation and Ideas of Protection and Restoration of Aquatic Ecosystems in Rivers and Lakes of China

Based on the investigation and analysis of protection and restoration of aquatic ecosystems in rivers and lakes of China, the ideas and measures of restoring aquatic ecosystems were proposed to build healthy aquatic ecosystems of rivers and lakes in China, such as setting scientific and clear goals, improving the standard adopted by wastewater treatment plants, controlling sources of pollutants and intercepting pollutants, collec- tion of blue-green algae, water transfer, dredging, reducing the quantity of blue-green algae, restoring reed wetlands on a large scale, combing dredging and base raise of restored reed wetlands, making full use of microorganisms, and implementing effective management, technology integra- tion and innovation.

Eutrophication of Aquatic Ecosystems： A Viewpoint on the Environmental Impact of Climate Change

Environmental concerns associated with nutrient-oriented eutrophication phenomenon have become a serious issue and a major cause of water quality deficiency nowadays. This necessitated eutrophication to occupy a front seat in research accompanied with climate change. Climate change has revealed to be a key player and a main contributor in the occurrence of such phenomenon. This paper discusses the ever-growing concern about eutrophication as a cause of climate change. Climate change affects storms intensity, changing the precipitation regime and increasing temperature. These effects increase the nutrient loading diffusion and cause excessive nutrients accompanied with storm water runoff, domestic wastewaters, and agricultural discharges to pour into water bodies. Eutrophication conversely contributes in the global wanning by releasing greenhouse gases from deoxygenated waters and sediments. Some control and mitigation measures are needed to fight climate change and achieve desired water quality goals. These measures include mitigation of climate change causes, enhancement of natural ecohydrological processes, application of proper integrated water resource management and participation of communities and governments.

Microplastics in Freshwater Environments and Implications for Aquatic Ecosystems: A Mini Review and Future Directions in Ghana

Microplastics have a constant effect on aquatic life and are constantly being researched, they have been gradually observed and analysed in marine and freshwater ecosystems, and possible effects in freshwater ecosystems are rising in importance. A literature review has been completed to outline the present state of awareness of microplastics in freshwater ecosystems in Ghana;in particular, the environmental fate, sources, effects in aquatic life and implications on their environments. Although we found that there was a dramatic increase in research and publications on these subjects, relatively few studies had examined the sources, fate and impacts of microplastics in the water bodies of Ghana and there was insufficient data on the extent of microplastics in freshwaters in Ghana. Studies in which Ghanaian waterbodies had quantified microplastics were considered of the greatest importance. We further assess current depth of knowledge of microplastics in aquatic ecosystems in which Ghanaian ecosystem-specific information was not readily available. Although this study may not be a comprehensive overview of the findings, it is assumed that this is an objective representation of the existing state of awareness about microplastics in the aquatic environment in Ghana.

Perspectives on atmospheric mercury and its fate in aquatic ecosystems

Mercury (Hg) is a neurotoxin to humans and wildlife that has a quantitatively important gas phase that makes its atmospheric cycle an important part of exposure pathways to these organisms. The important atmospheric forms are elemental Hg (Hg(0)), inorganic gas phase Hg (HgH gs ), and inorganic particulate Hg(HgIIp). Each form has different behavior depending on its chemical and physical properties. Generally, scientists have found with trace metal clean sampling and analytical techniques, that background Hg levels are 1—2 ng/m\+3 in air, 0.1—2 ng/L in surface waters, 5—25 ng/L in rainwater, and less than 0.1 μg/g in sediments remote from natural Hg minerals and wastewater sources. Values in excess of these concentrations generally indicate local anthropogenic influences or contaminated samples. Broad scale estimates of Hg inputs to the atmosphere suggest that annual anthropogenic fluxes to the atmosphere as Hg(0) are about 40 percent of the total global cycle, oceanic evasion is about 40 percent, and (by difference) the remaining input to the global cycle (20 percent) is evasion from terrestrial sources, largely via soils and vegetation. This paper summarizes recent data that will constrain estimates from these sources. For example, terrestrial sources could approach 40 percent and annual anthropogenic inputs be correspondingly less. Furthermore, a historic perspective is needed because Hg has cycled atmospherically over geologic time. In addition to the uncertainty in source quantification, methylation must be a focus of risk analysis, because this process is responsible for risks to human and ecosystem health for almost all modern day Hg exposures.

Regionalization Methodology Systems of Aquatic Ecosystems in China and the Case Study of Huaihe River Basin

本文提出的水生态区划方法体系包括指导思想、基本原则、分区方法、命名与编码规则几个部分。其核心指导思想是科学发展观及人与自然和谐的理念;基本原则有区域相关性原则、协调原则、主导功能原则和分及区划原则;分区方法、命名与编码规则则随分区等级和研究尺度而异。本文采用2级分区的思路,提出了全国水生态区划分方案,包括6个水生态一级区和34个水生态二级区。基于以下3类7种水生态服务功能:水生态保育类(包括水源涵养、水土保持和物种保护),水生态调控类(包括洪水调蓄和生境维持),水生态服务类(包括产品提供和景观保障),以淮河流域为例,将3级水生态区划方法应用于流域尺度。在实例区共划分出2个水生态一级区、3个水生态二级区和21个水生态三级区。

Trophic transfer of mercury and methylmercury in an aquatic ecosystem impacted by municipal sewage effluents in Beijing, China

Gaobeidian Lake, located in Beijing, China, serves as a recipient lake for efluents from a large municipal sewage treatment plant （MSTP）. In order to evaluate the effects of discharging MSTP efluent on the mercury contamination of the local aquatic ecosystem, sediment cores, water, plankton, fish, and turtle samples were collected from Gaobeidian Lake for mercury speciation analysis. High concentrations of total mercury （T-Hg） were detected in sediment cores （5.24–17.0 μg/g dry weight （dw）, average： 10.1 μg/g）. The ratio of methylmercury （MeHg） to T-Hg was less than 0.3% in sediments and ranged from 35% to 76% in biota samples. The highest level of T-Hg and MeHg were found in aquatic bryophyte and crucian carp （3673 and 437 ng/g dw, respectively）. The relative contents of MeHg were significantly correlated with trophic levels （R2 = 0.5506, p 0.001）, which confirmed that MeHg can be bio-transferred and biomagnified via food chain in this aquatic ecosystem.

Review of Restoration Technology and Multi-environmental Factors Analysis of West Lake Ecosystem in Hangzhou City

The urban lake ecosystem has the characteristics of long-term,complex and comprehensive in its ecological restoration process because it is related to social and economic activities at multiple levels.Located in Hangzhou City,China,the West Lake is a national-level scenic spot and a world heritage cultural landscape.It provides key ecosystem services for the city and has a significant impact on the urban ecological environment and the well-being of citizens.The West Lake has undergone an 1800-year governance process in history,realizing the harmonious coexistence with Hangzhou City.Since modern times,due to the rapid development of urbanization and industrialization,the water quality of the West Lake and its freshwater ecosystem have been greatly damaged.Since 2002,Hangzhou City has achieved the overall restoration of the West Lake ecosystem through a series of measures,such as water diversion projects,dredging projects,and the West Lake comprehensive protection project,and the water environment and lakeshore landscape have been greatly improved.This study analyzed the restoration technology of the West Lake ecosystem from two scales of the watershed and the site and discussed the water ecological governance system of the West Lake in the past 20 years.Through thedata analyses of the West Lake land use,vegetation,TP,TN,NH_(3)-N,COD_(Mn) and other multi-environmental factors,the results showed that the water quality,transparency and eutrophication of the West Lake had been greatly improved.At the same time,the application of large-scale restoration methods and technologies also required long-term observation,and attention should be paid to the proliferation of alien species and the loss of heritage value,so as to further avoid potential ecological risks caused by ecological restoration.

Eco-toxicity and health risk assessment of polycyclic aromatic hydrocarbons in surface sediments of Burullus Lake in Egypt

Polycyclic aromatic hydrocarbons(PAHs)are ubiquitous environmental contaminants of growing concern due to their potential ecological and human health risks.This study presents a comprehensive assessment of PAHs contamination in the surface sediments of Burullus Lake,a vital and second largest delta lake in Egypt.The aim was to evaluate the eco-toxicity and potential health risks associated with the presence of these compounds.Surface seven sediment samples were collected from various drains in the southern part of Burullus Lake.Soxhlet extraction method was employed to extract PAHs(16PAHs)from the sediment sample.Analytically,target compounds were located using HPLC.The results showed that samples contained PAHs levels ranging from 0.038×10^(-6)to 0.459×10^(-6),which is considered heavily polluted by the European standard for PAHs pollution.Additionally,there was no apparent source of PAHs in the ElKhashah drain or the Brinbal Canal,as HPLC found none of the compounds.The most prevalent compound in sediment samples along the study area was fluoranthene.The diagnostic indices in the present study indicated that the hydrocarbons in the region originated from pyrolytic and man-made sources along the drains of Burullus Lake.The principal component analysis(PCA)and diagnostic ratios revealed that coal combustion and pyrolytic sources were responsible for the PAHs contamination in the surface sediments.The non-carcinogenic risk(HI),which is the product of the HQs for the adult and child populations,respectively,was calculated.HI values under 1,therefore,demonstrated that they had no carcinogenic effects on human health.TEQs and MEQs in the sediments of Burullus Lake do not have a cancer-causing impact on people.For the safety of nearby wildlife,aquatic life,and people,all activities that raise petroleum hydrocarbon levels in Burullus Lake must be adequately regulated and controlled.According to the ecological risk assessment,there is little chance that PAHs will be found in the sediments of Burullus Lake.This study underscores the urgent need for effective pollution control measures and regular monitoring of PAHs levels in Burullus Lake sediments to protect the aquatic ecosystem and public health.It also highlights the importance of considering eco-toxicity and human health risks in integrated risk assessments of PAHs-contaminated environments.

A continuing 30-year decline in water quality of Jiaojiang Estuary, China

A quantitative description of a long-term series of aquatic environmental factors and their spatial distributions was generated using measured data from the Jiaojiang Estuary from 1982 to 2011. The aquatic environmental factors included suspended matter, salinity, and nutrients. Based on these factors, the aquatic ecosystem health in the Jiaojiang Estuary over the last 30 years was analyzed. The results indicated that the suspended matter concentration in the estuary was mainly affected by the amounts of suspended sediment and solid waste, with the value fluctuating over a long period, and the range of high concentration expanded continually; the salinity was mainly affected by precipitation and surface water resources, showing an overall decreasing trend, and the region with low salinity moved seaward and toward the reclamation areas; and the nutritional status, mainly affected by discharge of industrial wastewater and domestic sewage, was satisfactory in the 1980s and 1990s, but the status became severe in recent years. Reclamation had a great influence on these three factors： high reclamation strength led to a significant increase in the suspended matter concentration and a deterioration of the nutritional status, and the reclamation rate was negatively related with the salinity in the estuary. There was a significant positive correlation between the health status of the aquatic ecosystem and salinity, with a correlation coefficient of 0.93. The correlation coefficient between the health status and nutritional status was -0.71, while the correlation between the suspended matter concentration and health status was not as significant as that of the other two factors. The dynamics of the aquatic environment could be divided into four stages： sustainable health from the 1980s to the 1990s, continued deterioration from 2000 to 2003, improvement from 2004 to 2005, and secondary deterioration from 2006 to 2011. The Jiaojiang Estuary is faced with imminent environmental pressure at present.

The Global Science of Integrated Water Governance

Abstract： This study discusses the benefits of establishing a broader discipline of water science, based on the organizing mechanism of PES-W （payments for ecosystem services on the watershed scale）. PES-W is derived from an extension of governance analyses of 163 watershed-based PES （payments for ecosystem services） programs, and from the integrative decision mechanism of IPES （integrated payments for ecosystem services） to generalize the PES approach. PES-W reflects three interrelated perspectives fundamental to the global science of integrated water governance： （1） the ecological and economic perspective to integrate human incentives for integrated water resources governance; （2） the sociological and ecological perspective to form partnerships for meta-monitoring and recta-funding for integrated watershed governance; and （3） the scientific and sociological perspective to develop organizing botmdaries based on technology, lifestyle, entrepreneurship and organizing infrastructure for integrated aquatic ecosystem governance. This study is intended to communicate with the international scientific communities for establishing an advanced, academic, and practical multidisciplinary field of the global science of integrated water governance as a critical condition for sustainable development in human societies.

Cr （Ⅲ） Removal from Synthetic Waste Water by Using Water Pond Mud

The pollution of aquatic ecosystem by heavy metals has assumed serious proportions due to their toxicity and accumulative behavior. The toxicity metal is dependent on its chemical form and therefore removal of metal is more meaningful than the estimation of its concentrations. In this study, the batch experiments were carried out under 30℃ to study the effect of pH, initial Cr concentration, adsorbent dose and contact time on the removal of Cr （lII）. The maximum adsorption efficiency （99%） was observed when 1.5 g of pond mud was used for removal ofCr （Ⅲ） from test solution containing 150 mg·Cr / 100 ml. The optimal pH and contact time recorded during the study were 6 and 10.0, respectively.

Status of aquatic organisms resources and their environments in Yangtze River system(2017-2021)

The Yangtze River is the mother river of China.To promote the aquatic ecosystem protection of the great river,the Project of Yangtze Fisheries Resources and Environment Investigation(2017-2021)supported by the Ministry of Agriculture and Rural Affairs,P.R.China carried out by 24 institutes and universities that located in the Yangtze River basin surveys the status of(1)fish species composition and spatial distribution,(2)current fish abundance,(3)endangered fishes,(4)Yangtze finless porpoise,(5)aquatic eco-environments,(6)water-level fluctuation areas,(7)capture fisheries and recreational fisheries of the Yangtze River mainstream and 10 of its main tributaries,including Yalong River,Heng River,Min River(including Dadu River),Chishui River,Tuo River,Jialing River,Wu River,Han River,Dongting Lake and Poyang Lake.The results showed that there were 443 fish species(belonging to 163 genus,37 families,and 18 orders)before 2017,but only 323 fish species(including 15 new recorded exotic species)were recorded in the project of 2017-2021.Among them,Cyprinus carpio,Carassius auratus,Hypophthalmichthys molitrix,Pelteobagrus fulvidraco,Coilia brachygnathus,Silurus asotus,Saurogobio dabryi,Ctenopharyngodon idellus,Pelteobagrus nitidus,Hemiculter leucisculus,Siniperca chuatsi,Coreius heterodon,Culter alburnus,Parabramis pekinensis,and Aristichthys nobilis were the dominant species across the whole Yangtze River system.It is estimated that there were 886 million individuals weighing 124.8 million kg,merely equivalent to 27.3%of the resources in 1950s,30.9%of the resources in 1960s,or 58.7%of the resources in 1980s.In the new list of protected fishes that recorded in the Yangtze River system,only 15 of 29 were collected in this project of 2017-2021.Psephurus gladius has been affirmed to be Extinct by International Union for Conservation of Nature(IUCN).The wild individuals of Tenualosa reevesii and Luciobrama macrocephalus have disappeared for many years and maybe have been extinct already.Acipenser dabryanus has been affirmed to be Extinct in the Wild by IUCN.The natural propagations of A.sinensis,Myxocyprinus asiaticus and Trachidermus fasciatus have been interrupted for many years.The populations of Yangtze finless porpoise in the Yangtze River mainstream,Dongting Lake and Poyang Lake have steadily rising sizes and expanding distributions in 2017-2021.Parts of them migrate from one region to another with the seasons,which would result in the fluctuation of Yangtze finless porpoise population within some regions.The conventional indicators of water quality in the Yangtze River system were good and conformed to the water quality criteria of fishery in 2017-2021.In the last 40 years,the maximum surface water area in the Yangtze River basin extended to approximately 63,360 km2,the minimum surface water area covered approximately 26,396 km2,and the seasonal water-level fluctuation areas occupied approximately 36,964 km2.Compared with 1984-2000 period,the 2001-2020 period witnessed an overall decreasing trend in the frequency of surface water occurrence within about 25,869 km2 of aquatic areas.From 1984 to 2000 period to 2001-2020 period,permanent surface water has decreased by nearly 8,750 km2.In 2017,the fishermen were mainly 40-60 years old and their educational levels were mainly lower than junior high school.In 2017,most anglers were older than 40 and used hand rod and/or sea rod.Their average catch of each time was mainly less than 1 kg.Results suggested that the fishing ban in key waters of the Yangtze River basin is not only an ecological project of aquatic ecosystem conservation,but also a livelihood project for the fisherman to embrace industrial transformation and improve their living conditions.After the implementation of the fishing ban,the fisheries resources would gradually recover,and the Yangtze finless porpoise population size would also see a steady increase.However,the endangered species would remain threatened for a long time.The degraded waterbodies and water-level fluctuation areas would be the key restrictive factors for future aquatic ecosystem recovery in the Yangtze River basin.Since this survey was carried out before the fishing ban,the current results could provide a baseline for future evaluation of the effect of the Yangtze River fishing ban.

Application of Planarian Brain Regeneration: Detection of Water Pollution

Due to over industrialisation, the environmental pollution problem is becoming increasingly serious, especially in aquatic ecosystems. Compared with traditional physical and chemical detection methods, the use of biological indicators has become popular. The freshwater planarian Dugesia japonica is distributed extensively in aquatic ecosystems and has been applied to the area of environmental toxicology for its high chemical sensitivity. Moreover, D. japonica also has a powerful regenerative capability in which the injured planarian can regenerate a new brain in 5 days and complete an adult individual remodelling in 14 days. Therefore, it has been used as a new model organism in the field of neuro-regeneration toxicology. In our past study, D. japonica can be used as a biological indicator to detect water pollution. This can provide basic data for the detection of water pollution and provide a warning system in regard to aquatic ecosystems.

Environmental Deterioration of the Tecomate Coastal Lagoon, in the Guerrero State, Mexico

An exhaustive field study was undertaken between November 2011 and August 2012, with the aim to know the causes of the environmental deterioration of the Tecomate Lagoon, in the Guerrero state, Mexico. Data of temperature, dissolved oxygen, salinity parameters and depth of the lagoon were interpolated using the Kriging geostatistical method to generate a prediction surface. The lagoon registered a great variation in its saline concentration, which ranged from 8.0 to 65.0 ppt, with the lowest values in November 2011 and the highest at May 2012. The great variability in the salinity throughout the year contributed in significant form to the lagoon’s instability. An average water temperature of 32?C and dissolved oxygen levels of 4.49 to 7.44 mg/L were recorded. The low depth registered in the lagoon (mean = 1 m), is related to fluvial and marine processes, both of which modify depth through the transport of sediment to its interior. Currently, fishing is scarce, with the mangrove forest in some areas in a process of deterioration due to a lack of moisture. The lagoon system is undergoing a process of environmental deterioration, with an advanced ecological succession and non-aquatic vegetable species colonizing the area surrounding the lagoon.

Environmental Deterioration of the Tecomate Coastal Lagoon, in the Guerrero State, Mexico

An exhaustive field study was undertaken between November 2011 and August 2012, with the aim to know the causes of the environmental deterioration of the Tecomate Lagoon, in the Guerrero state, Mexico. Data of temperature, dissolved oxygen, salinity parameters and depth of the lagoon were interpolated using the Kriging geostatistical method to generate a prediction surface. The lagoon registered a great variation in its saline concentration, which ranged from 8.0 to 65.0 ppt, with the lowest values in November 2011 and the highest at May 2012. The great variability in the salinity throughout the year contributed in significant form to the lagoon’s instability. An average water temperature of 32?C and dissolved oxygen levels of 4.49 to 7.44 mg/L were recorded. The low depth registered in the lagoon (mean = 1 m), is related to fluvial and marine processes, both of which modify depth through the transport of sediment to its interior. Currently, fishing is scarce, with the mangrove forest in some areas in a process of deterioration due to a lack of moisture. The lagoon system is undergoing a process of environmental deterioration, with an advanced ecological succession and non-aquatic vegetable species colonizing the area surrounding the lagoon.

Significance of the carbon sink produced by H_2O–carbonate–CO_2–aquatic phototroph interaction on land

One of the most important questions in the science of global change is how to balance the atmospheric CO2 budget. There is a large terrestrial missing carbon sink amounting to about one billion tonnes of carbon per annum. The locations, magnitudes, variations, and mechanisms responsible for this terrestrial missing carbon sink are uncertain and the focus of much continuing debate. Although the positive feedback between global change and silicate chemical weathering is used in geochemical models of atmospheric CO2, this feedback is believed to operate over a long timescale and is therefore generally left out of the current discussion of human impact upon the carbon budget. Here, we show, by synthesizing recent findings in rock weathering research and studies into biological carbon pump effects in surface aquatic ecosystems, that the carbon sink produced by carbonate weathering based on the H2O- carbonate-CO2-aquatic phototroph interaction on land not only totals half a billion tonnes per annum, but also displays a significant increasing trend under the influence of global warming and land use change; thus, it needs to be included in the global carbon budget.

Recent insights into aquatic viruses: Emerging and reemerging pathogens, molecular features, biological effects, and novel investigative approaches

Aquatic viruses are naturally present in the aquatic environment and the number of viruses is staggering.Various multicellular organisms in aquatic ecosystems may be infected,cross-species transmitted,manipulated,and killed by aquatic viruses,which can lead to cascading ecological effects.The viruses in unicellular aquatic organisms can alter interactions between host individuals,and are essential in effecting or maintaining the dynamics of aquatic microbial communities,horizontal gene transfer,biodiversity,and modulating ecological processes globally.Meanwhile,hosts also impact viral abundance and diversity.Microbial diversity drives multifunctionality in ecosystems,while viruses shape complex microbial communities and are crucial for ecosystem functioning.This review focuses on molecular,genetic,evolutionary,and ecosystemic advances related to emerging and reemerging aquatic viruses,presents the contexts,novel tools,and investigative approaches pertaining to the study of aquatic virology,and discusses the mechanisms by which viruses affect aquatic ecosystems.The paper provides an efficient and broadly-based blueprint for improving understanding of aquatic viruses.