Natural Discharge Research Articles

Euphemism of Human Physiological Needs From the Perspective of Chinese and Vietnamese

It can be said that the language reflected a national identity, its contains the nation's cultural background and ways of thinking. Euphemism reflects a national cultural system and embodies different cultural patterns. There are a lot of cultural connotations in Chinese and Vietnamese language, although there are a lot of similarities between them, but there are still differences in the way of thinking and expression. By exploring the relationship between language and cultural factors and the influence of word euphemism, euphemism can be seen in two languages in language and culture two aspects of the homogeneous and heterogeneous. On language factor terms, two languages are using assonance to replace human nature discharge, whilst the dissimilaries are metonymy, loan word and personification. On culture factor terms, the convergences are metonymy and application of the semantically-contrary-word-euphemism, whilst the difference is Chinese euphemism using allusion but Vietnamese euphemism does not.

Hydro-geophysical monitoring of the North Western Sahara Aquifer System's groundwater resources using gravity data

The North Western Sahara Aquifer System (NWSAS) is characterized by unsustainable groundwater exploitation whose magnitude depends on the still unclear recharge value. It is extending over Libya, Tunisia, and Algeria, with an area of 106 km2. Here, we proposed an integrated approach combining Gravity Recovery and Climate Experiment (GRACE) and Global Land Data Assimilation System (GLDAS) data to reconstruct groundwater storage variations (ΔGWS) between April 2002 and July 2016. ΔGWS values are then introduced in a regional water budget equation accounting for the temporal evolution of withdrawals and natural discharge to calculate the time variations of the recharge. Yearly reconstruction of the recharge shows a large variability with alternation of net positive recharge and periods of net diffuse discharge associated with evaporation. The temporal average effective recharge value for the period of interest is 1.76 ± 0.44 mm yr−1. Lag-times for the recharge to reach the water table of 45 and 100 yrs characteristic of a diffuse recharge and corresponding vadose thickness in the range 3.90 ± 3.60 and 8.60 ± 8.10 m were identified using a cross-correlation analysis between reconstructed annual recharge and annual rainfall (AR). Statistical interpretation of the relation between ΔGWS, AR, and withdrawals shows that the anthropogenic effect (groundwater extraction) is the main controlling factor (99% of explained variance) in comparison to AR variations for the ΔGWS time series under consideration. A relation between long-term recharge and average annual rainfall (AAR) suggests a recharge representing 1.8 ± 0.3% of AAR in transboundary aquifers of the Saharan belt.

Design, Experiment, and Commissioning of the Passive Residual Heat Removal System of China’s Generation III Nuclear Power HPR1000

In response to a station blackout accident similar to the Fukushima nuclear accident, China’s Generation III nuclear power HPR1000 designed and developed a passive residual heat removal system connected to the secondary side of the steam generator. Based on the two-phase natural circulation principle, the system is designed to bring out long-term core residual heat after an accident to ensure that the reactor is in a safe state. The steady-state characteristic test and transient start and run test of the PRS were carried out on the integrated experiment bench named ESPRIT. The experiment results show that the PRS can establish natural circulation and discharge residual heat of the first loop. China’s Fuqing no. 5 nuclear power plant completed the installation of the PRS in September 2019 and carried out commissioning work in October. This debugging is the first real-world debugging of the new design. This paper introduces the design process of the PRS debugging scheme.

Trace elements in aquatic environment. Origin, distribution, assessment and toxicity effect for the aquatic biota

Trace elements contamination and accumulation in bottom sediment represents a risk to environment and aquatic biota. Their anthropogenic or natural discharge, extension and cumulation can cause large scale of ecological destructions. Bioaccumulation and biomagnification is capable of leading to toxic level of these chemical substances in fish and other fresh water organisms (benthos, zooplankton), even when the exposure is low. The fish contamination through trophic structure can cause serious consequences to human health.The aim of the manuscript was to assemble and summarize the latest literature on the environmental and the aquatic biota effects of trace element contamination of bottom sediments. The article is also a review of new methods for trace elements elimination and their assessment to impact on aquatic organisms. Based on collected scientific publications in last 20 years the most common and important trace elements in aquatic ecosystem are Chromium, Arsenic, Mercury, Cadmium and Copper. These compounds are dangerous for living organisms and can disrupt their homeostasis as well as a cardiovascular, nervous and digestive system. Nowadays exist many instrumental methods, which are available to determine the trace element concentration such as PMF, INNA, BCR, XRF and bioassay. In searched studies the most preferred and used analyse of trace element concentration in aquatic bottom sediments is bioassay. This biological method is good complement to physical and chemical analyses in procedures of sediment quality assessment. Bioassay method can indicate sensitive response of planktonic organisms to various trace elements and provide information about the real risk to aquatic life.

EFA-CFA integrated approach for groundwater resources sustainability in agricultural areas under data scarcity challenge: case study of the Souassi aquifer, Central-eastern Tunisia

Water resources become more and more threatened by the increasing request related to the population growth, especially in agricultural regions. This article focused on the design of a geo-model monitoring network controlling groundwater quality in the fast-growing agricultural area of Souassi, Central eastern Tunisia. The studied area is known for its dry climate conditions and information scarcity while they are most needed. In this case, the integrated approach based on the Exploratory Factor Analysis coupled to the Confirmatory Factors Analysis and geostatistics were performed in order to detect the most relevant factors intervening in the groundwater quality and their spatial variability in the shallow aquifer of Souassi. This investigation is based on data set of nine parameters (EC, Ca, Mg, Na, K, HCO3, SO4, Cl and NO3) determined in 30 samples from wells tapping the shallow aquifer of Souassi. The PCA results allowed illustrating that the groundwater quality in Souassi shallow aquifer is affected by both natural and anthropogenic factors. Developing the SEM led to identifying the most meaningful factors controlling the water mineralization. The geospatial interpolation using kriging technique enabled us to locate areas with high salinity values corresponding to the natural discharge zone of the aquifer as well as areas with high rate of nitrate coinciding essentially with olive fields in the central zone. Under limited database, the results allow highlighting the risk zones in the aquifer. This could assist in establishing sustainable agricultural activities while helping to solve environmental degradation of water resources in the study area.

Impact assessment of the three gorges reservoir on the contribution rate for diversion through the three outlets

The Dongting Lake distributes water and sediment of the Yangtze River through the three outlets. Influencing factors of the diversion capacity are complicated. In order to evaluate the influences of the operation of the Three Gorges Reservoir (TGR) on the diversion of the three outlets, this paper investigates systematically the variation process of the runoff at the three outlets based on substantially raw data and principles of variable control. By using comparative analysis and the calculation method of runoff reduction, the change magnitude of the runoff at the three outlets in different periods were quantified and the contribution rates of different influencing factors were estimated. Results show that (1) Inflow difference from the Yangtze River is the primary factor causing the runoff reduction of the three outlets. After the operation of TGR, the Yangtze River was in dry years. Therefore, over 60% of runoff reduction can be attributed to the variation of natural inflow discharge. (2) As the flow is retained by TGR, the runoff of the three outlets further reduced. From 2003-2008, the contribution rates of natural flow, sediment trapping and reservoir regulation to the runoff reduction at the three outlets were 76.19%, 13.49%, 10.32%, while their counterparts after optimal operation of TGR became 66.05%, 14.20% and 19.75% respectively. (3) Reservoir operation after the flood season showed the most significant impact on runoff of the three outlets, resulting in an increase in the number of shut-off days of the three-distributary channels from September to October, especially at Shadaoguan and Kangjiagang.

Scenario analysis for the sustainable development of agricultural water in the Wuyuer River basin based on the WEP model with a reservoir and diversion engineering module

Agricultural water use is increasing quickly with the rapid socioeconomic development observed in the Wuyuer River basin. Water withdrawal for agriculture over the past decade have seriously depleted the ecological water requirements in the basin and damaged the channel and downstream wetland ecosystems. Achieving sustainable development in the basin will require a balance between agricultural water exploitation and ecological water demands. In this paper, a reservoir and diversion engineering module was integrated with a dualistic distributed hydrological model (WEP model) to investigate the effects of agricultural water use on river discharge. Agricultural water shortages and yearly minimum river discharges between 2020 and 2050 under six agricultural water exploitation scenarios and one natural scenario were estimated based on the proposed model. The results showed that the dualistic hydrological process model was more suitable for basins with agricultural water resource exploitation and that the river discharge was significantly less than the natural discharge due to irrigation and reservoir filling, especially in drought years. Under the scenarios of high, middle and low water resource exploitation without ecological operations, agricultural development was unsustainable because of agricultural water shortages and ecological water scarcity. The evaluation of the guaranteed rates for the agricultural water supply and environmental flows showed that the low water resource exploitation scenario with ecological operations was the best option and that sustainable development could be achieved in the basin under this exploitation scenario in the future. However, implementing water management practices in the basin could result in certain economic losses. These losses could be offset by ecological protection funds for downstream wetlands. Overall, the model results could help to inform planning and investment decisions within the basin to improve the sustainable management of water resources.

Influence of pluviosity and floating population on the water quality of a neotropical costal river

The contamination of waterbodies is a worldwide concern due to the increasing urbanization and industrialization of the cities without good effluent management. Touristic cities can suffer with the number of people during high seasons periods, which can lead to an elevated use of natural resources and effluents discharges. Moreover, raining seasons, either high or low, can also play an important role in contaminating waterbodies once a dilution or concentration of contaminants may take place. The present study evaluated the water quality of the Tejereba River (Guarujá, Brazil) during the high season (January) and low season (March and May) in 2018. Reduction in water quality was observed in May, a month with low pluviosity and low tourism. The integrated data analysis (PCA) showed a positive correlation between the physicochemical parameters and the month of May, in which they were negatively correlated with pluviosity and the percentage of tourists. Despite the deterioration of water quality in May, no toxicity to Daphnia magna was observed. Our work showed that water quality (physicochemical and microbiological parameters), during the studied months, is more related to raining seasons than to the presence of tourists in Guarujá, Brazil.

Assessment of environmental water requirement for rivers of the Miankaleh wetland drainage basin

The Miankaleh wetland, one of the richest ecosystems in the north of Iran, has experienced an unprecedented environmental degradation caused by overexploitation of the water resources and climatic changes in recent years. This research aims to estimate the environmental water requirement (EWR) for the rivers that drain into the wetland. For this purpose, comprehensive data were collected through physiographic, climatic, hydrologic, ecologic, and field studies of the wetland and its drainage basin. To estimate the EWR, we applied several methods including the Tenant, the Eco-deficit, the flow duration curve, the Wetted-Perimeter method, and the physical habitat simulation model (PHABSIM) and the results were evaluated based on the natural discharge of the rivers before retrogression of the Miankaleh wetland. Further, the results showed that the consideration should be given to the Wetted-Perimeter and the PHABSIM Model for estimation of the EWR for the rivers of the Miankaleh wetland given the seasonality of the rivers and hydroclimatic condition of the study area. The mean annual EWR of the rivers was estimated between 0.12 and 2.03 m3/s, which is close to the values of the bank full flows. The current discharge of the rivers are less than the estimated EWR, showing the discharge rates do not meet the water requirement for aquatic species of the Miankaleh wetland

Flood Variability Determines the Location of Lobe‐Scale Avulsions on Deltas: Madagascar

AbstractRiver deltas grow through repeated lobe‐scale avulsions, which often occur at a location that correlates with the backwater lengthscale. Competing hypotheses attribute the avulsion node origin to either the morphodynamic feedbacks caused by natural flood discharge variability (backwater hypothesis) or to the prograding delta lobe geometry (geometric hypothesis). Here, using theory, historical flood records, and remotely sensed elevation data, we analyzed five lobe‐scale delta avulsions in Madagascar, captured by Landsat imagery. Avulsion lengths were 5–55 km, distances significantly longer than the backwater lengthscale and inconsistent with the geometric hypothesis. We show that the steep, silt‐bedded rivers of Madagascar have flood‐induced bed scour, driven by backwater hydrodynamics, that propagates farther upstream than the backwater lengthscale. The avulsion lengths are 3.1 ± 1.5 times the predicted flood scour lengths, similar to low‐gradient deltas, and consistent with backwater hypothesis. Results demonstrate that erosion initiated by nonuniform flows in the backwater zone is a primary control on delta avulsion locations.

Dangerous emissions of endogenous CO2 and H2S from gas blowouts of shallow wells in the Rome Municipality (Italy)

The southeastern zone of Rome city is located at the northwest periphery of the quiescent Colli Albano volcano. This zone is characterized by the presence of a shallow (depth ~ 45–50 m) gas pressurized aquifer that produces gas blowouts when it is reached by wells. Three gas blowouts occurred in this zone in 2003, 2008 (another one was discovered during the present study) and 2016 and in this paper we describe in detail the latter two. The emitted gas consists mostly of CO2 (>90 vol%) and contains a low but significant quantity of H2S (0.3–0.5 vol%) and it has the highest helium isotopic R/Ra value (1.90) of all Colli Albani natural gas discharges, suggesting its likely magmatic origin. In both the described gas blowouts, dozens of families had to be prudentially evacuated from their houses and the emitted gas killed some animals. We monitored, continuously or by discrete surveys, the soil CO2 flux, the indoor and outdoor air concentration of CO2 and H2S, the environmental parameters and we checked whether the cementation of the gas releasing wells had been effective. In both cases, the upper part of the wells had been partly closed with an inflating packer to avoid free gas dispersion in atmosphere; as a consequence gas diffused laterally from the wells into the permeable surficial soil up to reach the nearest houses creating hazardous indoor conditions, particularly for CO2 in some basements. During the well cementation operations, and in one case because of the packer rupture, gas and nebulized water were freely discharged from the wells into the atmosphere, and high air CO2 and H2S concentrations were found. Fortunately gas was quickly dispersed by strong winds. The positive results obtained in all the studied gas blowouts demonstrate that our applied geochemistry approach represents a model of intervention useful for the assessment of the hazard associated to accidental endogenous gas release. This model is of fundamental importance also to overcome the risk problems created by accidental gas blowout from wells in an urbanized environment, up to the safe return of the people in their evacuated houses.

Target Ecological Limits and Not Economic Growth

Economic growth has both benefits and detriments for the sustainability of human flourishing. Economic growth has resulted in increased natural resource utilisation and discharges of emissions and wastes, which is worrying from a sustainability perspective. However, economic growth is intrinsically not a bad thing. It has many beneficial aspects, in particular the increasing supply of necessary goods and services that are needed to facilitate the flourishing of a growing human population. Furthermore, all types of economic growth are not necessarily impacting negatively on the natural environment. The key point is that global policy should not simply target economic growth with the aim of constraining it and striving for negative growth as a means to solving environmental sustainability concerns. This paper outlines the concept of ecological limits associated with natural resource utilisation and discharge of harmful emissions and wastes. It suggests that, instead of targeting economic growth, policies should target specific natural resource utilisation and emission discharge rates that exceed their ecological limits. Action plans should be developed and implemented using socioeconomic and technological approaches that try to bring these specific utilisations or discharges back to within their ecological limits. This may impact negatively on economic growth in the short to medium term but it is targeting specific resources and emissions that are unsustainable and the economic growth associated with them only. In the longer term, these actions may facilitate economic growth, while remaining within ecological limits.

Response of the Mogan and Eymir lakes (Ankara, Central Anatolia) to global warming: Extreme events in the last 100 years

Mogan and Eymir lakes are shallow wetlands which are potentially susceptible to global warming. Previous geological studies demonstrated several complete desiccation and shrinkage events in Lake Mogan since the 1800s. Archival records show at least three desiccation events in 1910, 1934 and 1938, and many severe shrinkages later. Here, the significance of climatic and anthropogenic drivers is still a subject of curiosity. The back-analysis of the hydrological data during the regulator intervention indicates that Lake Mogan would have dried out in 1974, and would have shrunk considerably in the years 2007/2008 and 2017/2018 if human intervention was not involved. Our lake budget analysis shows that, assuming no human intervention and stream recharge, the water level of both lakes would have dropped below the threshold level in less than a week by natural downstream discharge, and the remaining volume of the lakes would evaporate in less than two years. This fact indicates the benefits of regulators for the protection of the lakes. The meteorological and lake budget data suggest that the underlying climatic threat over the studied lakes is high frequency (sub-decadal) rainfall scarcity coupled with long-term (several decades) insolation increase but not slow, steady deterioration of the climatic parameters.

Assessment of heavy metal pollution in Köyceğiz-Dalyan coastal lagoon watershed (Muğla) SW Turkey

This study is carried out to assess the water pollution in Koycegiz-Dalyan Coastal Lagoon Watershed located near the Mediterranean Sea in Mugla province, SW Turkey, by using heavy metal pollution index (HPI). A total of 30 samples were collected from the lakes, streams, groundwaters, the subaqueous hot and cold springs, and on-land hot springs, and Cr, Fe, As, Sb, and Pb concentrations were determined. Elevated concentrations of Fe, As, and Pb were detected in most of the samples; the sources of which are either the natural or anthropogenic discharge of the geothermal springs and seawater mixing. As and Pb concentrations in some locations are found to exceed both acute and chronic exposure criteria for aquatic life, posing a threat to the species hosted by these environments. To determine the magnitude of pollution, HPI calculations were carried out. The average and maximum HPI values for the cold waters are 297.1 and 1162.9, respectively, both of which are higher than the critical pollution index value. The highest HPI values are observed in samples taken from the Dalyan Channel and Alagol Lake. In general, pollution levels increase from north to south, reaching the maximum value at the outlet point, due to the increased contribution from thermal water discharge and mixing with seawater.

Incorporating Historical Spring Discharge Protection Into Sustainable Groundwater Management: A Case Study From Pearl Harbor Aquifer, Hawai‘i

Groundwater management policy around the world increasingly seeks to protect groundwater-dependent ecosystems and associated human uses and values. This includes uses of ecosystems and agricultural systems linked to natural spring discharge. Yet, there are few examples of practical tools to balance human groundwater use with ecological water demand related to spring discharge. Using a simulation optimization framework, we directly incorporate a spring discharge constraint into the analysis of sustainable yield for operationalizing groundwater policy in the state of Hawai‘i. Our application on the island of O‘ahu is a spring discharge-dependent watercress farm with historical, cultural, and ecological significance. This research provides decision-makers in Hawai‘i with information regarding the trade-off between groundwater pumping and spring discharge, which is connected to multiple benefits, including historical and cultural values in line with codified state beneficial use protections. Because this trade-off provides an important step in operationalizing sustainable yield policy in Hawaii, we conclude by discussing further conceptual and technical developments necessary to move groundwater policy in Hawai‘i closer to full incorporation of the public trust principles of the state water code.

Assessment of Surface Water -Groundwater Relationship in the Area Between Borg El Arab and West El Hammam, North West Coastal Zone, Egypt

The study area, between Borg El Arab and El Hammam, is recently subjected to intensive land reclamation projects aiming to cultivate about 57000 feddans. It is supplied by two main sources of irrigation, i.e. the surface water as a main source (Bahig canal and El Hammam canal), and the groundwater from more than 600 shallow wells tapping the Ralat aquifer (calcareous sandstone) of Plio-Pleistocene age as a supplement source. During the last three decades (1985 – 2014), conjunctive use of surface water together with groundwater has resulted in serious hydrologic problems e.g. water losses, canal seepage and water logging, where the depth to water level has risen up from about 20 m (1985) to less than 5.0 m (2014). Meanwhile, the groundwater salinity decreased during this period from more than 5000 ppm to less than 2000 ppm, indicating a dilution effect by seeped water. The water seepage from the dissecting canals is estimated in the present work by 65.18 x 106 m3/year replenishing the groundwater system in the down gradient areas. Might as well, the irrigation return flow through permeable soil in the study area is estimated by 4.125 x 106 m3/year due to the applied flood irrigation technique. In other words, 95% of the total groundwater replenishment is from the canal seepage, while only 5% from direct percolation. The investigation of wells tapping the Ralat aquifer in the study area has indicated that water levels are ranging from 21.0 m to 1.0 m above mean sea level. More than 57.6 x 106 m3/year (average 84% of the natural groundwater discharge) are pumping from such wells to get water of about 2000 ppm salinity, indicating a significant hydraulic connection between the surface water canals and the underlying aquifer. The calculated water balance of the Ralat aquifer has resulted in an amount of annual surplus water of the order of 11.705 x 106 m3/year as groundwater storage.

Modelling of surface river plume using set-up and input data files of Delft-3D model.

This data article presents set-up and input data files to model a surface river plume through curvilinear nested grid in double-way mode. The hydrodynamic modelling in river deltas with intense transport processes and complex bathymetry such as the Magdalena River delta, requires a mesh grid that ease the natural river discharge into the ocean. The aforementioned may be challenging due to the numerical scheme and stability restrictions of the numerical models that difficult having efficient and effective validated simulations. This dataset files are a reference to perform analysis of the hydrodynamic river deltas, meaningful for optimizing time and resources, easing the planning of measurement campaigns what reduce risks of the personnel and instrumentation during equipment deployment and field work .The application of the set-up and input data files of this data article is shown in Rueda-Bayona et al. [1].

Glycerol Utilization By Phytoplankton1.

Dissolved organic carbon (DOC) is an important source of carbon and energy for microbes, but whether it can be used by phytoplankton has not been systematically studied, and the underlying molecular metabolism remains poorly understood. Here, we investigated the ability of phytoplankton to utilize glycerol as a representative of DOC. The widespread presence and expression of glycerol transporter genes were found in transcriptomes and genomes, suggesting the glycerol utilization potential in the diverse marine phytoplankton. We surveyed 29 representative phytoplankton species (31 strains) from six phyla for their ability to use glycerol. Three types of responses were found: positive utilization (Type I), no response (Type II), and negative response (Type III). In all, 11 Type I species were further investigated in axenic cultures with different glycerol concentrations, and five species showed intrinsic glycerol utilizing ability without the aid of bacteria. The ability of species to use glycerol to support non-photosynthetic (DCMU treated) growth was consistent with their possession and expression of glycerol transporter genes. However, some species from the Type II and Type III also possess and express the genes, raising a question whether glycerol transporter in algae might have diversified its function to glycerol export or even non-glycerol transport. Our results show that glycerol could serve as organic carbon source, harmless xenobiotics, or growth inhibitors for phytoplankton depending on species, indicating that glycerol, including natural sources or human discharges, may shape the marine phytoplankton community structure, especially under low photosynthetic efficiency conditions.

Natural discharge changes of the Naryn River over the past 265 years and their climatic drivers

Originating in the Tianshan Mountains in arid Central Asia, the natural discharge change of the Naryn River is strongly affected by climate change. As the main source of water for the region, this river is crucial to both the natural environment and the socio-economic development. To extend the discharge record and better understand past and future changes in Naryn River discharge, we developed four tree-ring width chronologies and analyzed the relationship between tree growth and discharge. The resulting reconstruction dates back to 1753 and has an R2 of 0.374 (1939–2017). Interannual discharge variations of the Naryn River indicate that 1917 was the driest year of the past 265 years, while 1956 was the wettest. The record also indicates that the majority of extreme flood years occurred in the past century; prior to about 1900 C.E., the discharge of the Naryn River was relatively stable. Since 1900 C.E., discharge volume has gradually increased, as has discharge variability. At decadal time scales, the 2010s are notable for the frequency of major floods, whereas the 1910s were the driest. Between the 1870s and the 1910s, the Naryn River experienced a period of low discharge that continued for nearly half a century. The discharge of the Naryn River over the past 265 years appears to vary over quasi-periods of 60, 21, 11, and 2-4 years, which are driven by large-scale climate systems.

Electrically evoked force loss of the knee extensors is equivalent for young and old females and males.

Data are scant on sex-related differences for electrically evoked contractions, which assess intrinsic contractile properties while limiting spinal and supraspinal adaptations to mitigate fatigue. Furthermore, the few studies that exist use stimulus frequencies considerably higher than the natural motor unit discharge rate for the target force. The purpose of this study was to compare force loss to electrically evoked contractions at a physiological stimulus frequency among young females (n = 12), young males (n = 12), old females (n = 11), and old males (n = 11). The quadriceps of the dominant leg were fatigued by 3 min of intermittent transcutaneous muscle belly stimulation (15 Hz stimulus train to initially evoke 25% of maximal voluntary force). Impairment of tetanic contractile impulse (area under the curve) did not differ between sexes for young or old adults or between age groups, with a pooled value of 55.2% ± 12.4% control at the end of fatigue. These data contrast with previous findings at 30 Hz, when the quadriceps of females had greater fatigue resistance than males for young and old adults. The present results highlight the impact stimulus frequency has on intrinsic fatigability of muscle; the findings have implications for future fatigue paradigms and treatment approaches when utilizing electrical stimulation for rehabilitation. Novelty Fatigue was not different between sexes with a stimulation frequency comparable to discharge rates during voluntary contractions. These results highlight that stimulus frequency not only influences fatigue development but also between-group differences.