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hydrology, etc ; Bryconops; aluminum; anthropogenic activities; antioxidant activity; antioxidants; bauxite; biomarkers; fish; glutathione transferase; laws and regulations; liver; muscles; oxidative stress; research; sediments; Amazonia; Show all 17 Subjects
Abstract:
... The Eastern Amazon is rich in bauxite ore. The extraction and processing of bauxite lead to the mobilization of Aluminum (Al) and other metals in environmental. We evaluated the metals (Al, Mn, Ba, and Cr) concentration in tissue, water, and sediment associated with antioxidant and oxidative damage responses in Bryconops caudomaculatus. The samplings were done in two hydrological periods (post-rai ...
... Under changing environments, conventional methods based on an assumption of stationarity can lead to unreliable estimates of design rainfall quantiles. In this study, the trend of six extreme precipitation indices in the Beijing–Tianjin–Hebei region was analysed using different methods. Nonstationary models were established for annual maximum one-day precipitation (RX1d) and annual total precipita ...
... Physical and hydraulic properties of porous media are routinely measured/simulated at smaller scales e.g., pore and core. However, their determination at larger scales e.g., field and reservoir has still been a great challenge. Although understanding the scale dependence of transport modes in rocks and soils is essential, the porous media community still lacks in a solid theoretic framework. In th ...
... North-eastern Tasmania, Australia. Two quantitative methods for determining the bankfull stage of alluvial rivers from plotted channel cross-sections were assessed. Bankfull stage estimates determined using the minimum width-to-depth ratio and the first maximum of the bench-index were compared, and then evaluated against qualitative estimates of bankfull stage, using data from 89 cross-sectional s ...
dams (hydrology); hydrology, etc ; DNA barcoding; Triportheus; basins; freshwater fish; ichthyoplankton; larvae; phenology; rivers; Peru; Show all 11 Subjects
Abstract:
... The Amazon basin holds the world's largest freshwater fish diversity. Information on the intensity and timing of reproductive ecology of Amazonian fish is scant. We use a metabarcoding method by capture using a single probe to quantify species‐level ichthyoplankton dynamics. We sampled the Marañón and the Ucayali rivers in Peru monthly for 2 years. We identified 97 species that spawned mainly duri ...
... This comment discussed the calculation of thermodynamic parameters about the paper published in Journal of Contaminant Hydrology 243 (2021) 103906. Despite the paper's novelty and innovation, the distribution constant (Kd) with a dimension of L/mg is not the standard equilibrium constant (Kᵒ), therefore, it cannot be used to calculate the thermodynamic parameters. By analyzing the incorrect result ...
... The effects of inlet configurations in sediment retention ponds (SRPs) have been widely investigated by several researchers. However, when considering temperature differentials in the ponds where density and buoyancy change with temperature the challenges associated with the proper inlet design still exist. The buoyancy forces are generated due to the differences in temperature potentially changin ...
... One of the major advantages of satellite precipitation estimates is that they can provide a complete picture of precipitation systems; a difficult task to achieve using sparsely distributed rain gauges. This advantage greatly enhances our understanding of natural precipitation. Also, for this reason, it is difficult to know satellite-derived precipitation system performance using a direct “object- ...
... The stochastic simulation of deltas has always been one of the significant problems in the numerical simulation of reservoirs. Three problems of deltaic simulations are non-stationary geological characteristics in training images (TIs), insufficient quantity of TIs in certain regions and unavailable reuse of training parameters and models even after the first training, which have caused big challe ...
... Rain gauge networks are not adequate to capture the complex spatial structure of rainfall for meaningful urban flood studies. While radar and satellite precipitation products (SPPs) are being developed to alleviate the limitations of rain gauge networks, they need to be evaluated for regional applications. This study compared radar against 3 SPPs of IMERG (Integrated Multi-satellite Retrievals for ...
... Regional flood frequency analyses are highly affected by the number of gauged catchments and lengths of observation periods at the individual gauges. Therefore, information is unevenly distributed in the region of interest. In particular, the occurrence of single extreme floods that are observed or not observed at some gauges, depending on the observation period, may have a large impact on the reg ...
hydrology, etc ; algorithms; environmental science; prediction; Show all 4 Subjects
Abstract:
... Kalman filter (KF) and its variants and extensions are wildly used for hydrologic prediction in environmental science and engineering. In many data assimilation applications of Kalman filter (KF) and its variants and extensions, accurate estimation of extreme states is often of great importance. When the observations used are uncertain, however, KF suffers from conditional bias (CB) which results ...
hydrology, etc ; equations; mathematical models; solutes; Show all 4 Subjects
Abstract:
... One-dimensional models of solute transport typically rely on the advection–dispersion equation (ADE) and thus cannot accurately simulate the solute transport phenomenon in rivers with storage zones. Our proposed model employs a minimum number of parameters (only one parameter) and focuses on simplicity and physical reasoning. This study mainly aims at investigating the applicability of nonlinear f ...
hydrology, etc ; climate; drought; periodicity; watersheds; Show all 5 Subjects
Abstract:
... The Huaihe River Basin is located in China’s north-south climate transition belt, where massive droughts occurred in history. To comprehensively capture how climate extremes have behaved in the past, this paper analyzed the trend, change point, and periodicity of drought at multiple spatial-temporal scales based on the Standardized Precipitation Indexes (SPI). And the historical simulation experim ...
... With global warming and rapid urbanization, urban agglomerations (UAs) over the Loess Plateau (LP) are suffering from various urban disasters. Urbanization has aggravated the decreasing trends of extreme precipitation in Taiyuan and Xi'an UAs and enhanced the increasing trends of extreme precipitation in Luoyang, Hohhot and Xining UAs during 1979–2018. Meanwhile, the number of light rain days decr ...
... This paper presents a numerical test problem that was used as the basis for ranking the river basin management models that participated in a tender for a World Bank-funded project in India. The problem is deterministic, and it involves a set of constraints and management objectives that were of interest to the Narmada Control Authority. The test problem had five reservoirs, seven off-stream and fo ...
dams (hydrology); hydrology, etc ; basins; ecosystems; energy; issues and policy; politics; riparian areas; rivers; water power; watersheds; Show all 11 Subjects
Abstract:
... Water resources management in the Lancang-Mekong River Basin (LMRB) is challenging in face of the complex trans-national geopolitical context, the acceleration of hydropower dam expansion, and the growing demands for energy, food, and riverine ecosystem preservation across the basin. Centralised management through coordinated operation of all the basin water infrastructures (“hard cooperation”) ac ...
... Estimation of pan evaporation (Epan) is an important issue for planning and management of available water resources. In the present study, the accuracy of a new deep learning method, long short-term memory (LSTM) with grey wolf optimization (GWO), in modelling Epan using limited climatic variables as input is investigated. The outcomes of the LSTM-GWO are compared with the single LSTM and advanced ...
hydrology, etc ; drought; hybridization; hybrids; prediction; Show all 5 Subjects
Abstract:
... Drought is a prolonged period of low precipitation that negatively impacts agriculture, animals, and people. Over the last decades, gradual changes in drought indices have been observed. Therefore, understanding and forecasting drought is essential to avoid its economic impacts and appropriate water resource planning and management. This paper presents a recent literature review, including a brief ...
... We develop a hydro-chemical model to simulate incipient karst generation in three-dimensional (3D) jointed layered carbonates. The discrete fracture networks consist of fractures that are represented by two-dimensional (2D) planes. The numerical model couples the important physical processes of fluid flow, reactive transport, and dissolutional growth of fracture aperture. We represent the typical ...