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Topic Review
Tools for Shoreline Change Analysis and Detection
A shoreline is the point of the physical border between land and water. While this definition looks simple, it is indeed challenging in its practical application. The position of the shoreline changes through time due to cross-shore and alongshore sediment movement in the littoral zone, and through changes in water levels. Shoreline change analysis and detection studies have progressed from using simple observation (description) from historical maps and topographical maps to employing high-resolution multi-temporal satellite images with remote sensing and Geographic Information System (GIS) approaches for a better understanding of the subject.
  • 3.2K
  • 05 May 2022
Topic Review
Leaf area index (LAI)
Leaf area index (LAI) is an important vegetation leaf structure parameter in forest and agricultural ecosystems. Remote sensing techniques can provide an effective alternative to field-based observation of LAI. Different system configurations (passive, active, and multisource sensors on different collection platforms) has been used to estimate forest and crop LAI. The ease of use of empirical models supports these as the preferred choice for forest and crop LAI estimation. In terms of scale issues, both spectral and spatial scales impact the estimation of LAI. Uncertainty coming from various sources results in reduced accuracy in estimating LAI. 
  • 3.2K
  • 26 Oct 2020
Topic Review
Exposure Routes and Health Risks Associated with Pesticides
There are four main pesticide application methods, including hydraulic spraying, backpack spraying, basal trunk spraying, and aerial spraying. Pesticide application methods are mainly selected by considering the habits of target pests, the characteristics of target sites, and the properties of pesticides. Humans are directly exposed to pesticides in occupational, agricultural, and household activities and are indirectly exposed to pesticides via environmental media, including air, water, soil, and food. Human exposure to pesticides occurs mainly through dermal, oral, and respiratory routes. People who are directly and/or indirectly exposed to pesticides may contract acute toxicity effects and chronic diseases. Although no segment of the general population is completely protected against exposure to pesticides and their potentially serious health effects, a disproportionate burden is shouldered by people in developing countries. Both deterministic and probabilistic human health risk assessments have their advantages and disadvantages and both types of methods should be comprehensively implemented in research on exposure and human health risk assessment. Equipment for appropriate pesticide application is important for application efficiency to minimize the loss of spray solution as well as reduce pesticide residuals in the environment and adverse human health effects due to over-spraying and residues. Policymakers should implement various useful measures, such as integrated pest management (IPM) laws that prohibit the use of pesticides with high risks and the development of a national implementation plan (NIP) to reduce the adverse effects of pesticides on the environment and on human health. 
  • 3.2K
  • 30 Jul 2022
Topic Review
Archimedes Screw Turbines
Archimedes Screws Turbines (ASTs) are a new form of generators for small hydroelectric powerplants that could be applied even in low head sites. ASTs offer a clean and renewable source of energy. They are safer for wildlife and especially fish. The low rotation speed of ASTs reduces negative impacts on aquatic life and fish. Considering the flexibility and advantages of ASTs, they offer economic, social, and environmental advantages to support sustainable development to: - Increase the number of suitable sites and maximize power generation.- Retrofit old dams or upgrade current dams or mills to make them economically (power generation) and environmentally (renewable energy) reasonable.- Reduce the hydroelectricity major operational and/or maintenance costs.- Reduce the disturbance of natural erosion and sedimentation processes.- Make hydropower generation safer for aquatic wildlife, especially for fish.- Generate electricity for small communities, developing countries, and regions with limited access to the power grid or other infrastructures, or regions that are hard to access or connect to the power grid.  
  • 3.1K
  • 12 Jan 2022
Topic Review
Weichselian Glaciation
Weichselian glaciation[upper-alpha 1] refers to the last glacial period and its associated glaciation in northern parts of Europe. In the Alpine region it corresponds to the Würm glaciation. It was characterized by a large ice sheet (the Fenno-Scandian ice sheet) that spread out from the Scandinavian Mountains and extended as far as the east coast of Schleswig-Holstein, the March of Brandenburg and Northwest Russia. In Northern Europe it was the youngest of the glacials of the Pleistocene ice age. The preceding warm period in this region was the Eemian interglacial. The last cold period began about 115,000 years ago and ended 11,700 years ago. Its end corresponds with the end of the Pleistocene epoch and the start of the Holocene. The German geologist Konrad Keilhack (de) (1858-1944) named Weichselian glaciation using the German-language name (Weichsel) of the River Vistula (Polish: Wisła) in present-day Poland.
  • 3.1K
  • 14 Oct 2022
Topic Review
Organic Fouling
Organic fouling in the forward osmosis process is complex and influenced by different parameters in the forward osmosis such as type of feed and draw solution, operating conditions and type of membrane. In this article, we reviewed organic fouling in the forward osmosis focussing on wastewater treatment applications. Model organic foulants used in the forward osmosis literature were highlighted, followed by the characteristics of organic foulants when real wastewater are used as feed solutions. The present study evaluated various physical and chemical cleaning protocols for organic fouled membrane and the efficiency of cleaning methods for the removal of organic fouling in the forward osmosis process. The study made recommendations on future cleaning technologies such as Ultraviolet and Ultrasound. Generally, a combination of physical and chemical cleaning is the best for restoring the water flux in the FO process.
  • 3.1K
  • 27 Oct 2020
Topic Review
Sources of Arsenic in the Aquatic Environment
Arsenic is an element that is distributed globally and is abundant in the Earth’s crust (20th most abundant element) and seawater (14th most abundant element). It is classified as a metalloid and exhibits both metallic and non-metallic properties. The high solubility and mobility of arsenic in aquatic environments affects its global cycling. Furthermore, the biological processes in the aquatic environment are discussed, especially the possible microbe-mediated reactions of arsenic in sediments. In addition, various environmental factors, such as redox conditions, pH, and salinity, which influence the transformation of arsenic species.
  • 3.1K
  • 04 Jan 2023
Topic Review
Removal of Inorganic Nitrogen from Wastewater
Water contamination due to various nitrogenous pollutants generated from wastewater treatment plants is a crucial and ubiquitous environmental problem nowadays. Nitrogen contaminated water has manifold detrimental effects on human health as well as aquatic life. Consequently, various biological and bioelectrochemical treatment processes are employed to transform the undesirable forms of nitrogen in wastewater to safer ones for subsequent discharge.
  • 3.1K
  • 27 May 2022
Topic Review
Climate Oscillation
A climate oscillation or climate cycle is any recurring cyclical oscillation within global or regional climate, and is a type of climate pattern. These fluctuations in atmospheric temperature, sea surface temperature, precipitation or other parameters can be quasi-periodic, often occurring on inter-annual, multi-annual, decadal, multidecadal, century-wide, millennial or longer timescales. They are not perfectly periodic and a Fourier analysis of the data does not give a sharp spectrum. A prominent example is the El Niño Southern Oscillation, involving sea surface temperatures along a stretch of the equatorial Central and East Pacific Ocean and the western coast of tropical South America, but which affects climate worldwide. Records of past climate conditions are recovered through geological examination of proxies, found in glacier ice, sea bed sediment, tree ring studies or otherwise.
  • 3.1K
  • 09 Nov 2022
Topic Review
Air Temperature Forecasting
The accurate forecast of air temperature plays an important role in water resources management, land–atmosphere interaction, and agriculture. However, it is difficult to accurately predict air temperature due to its non-linear and chaotic nature. Several deep learning techniques have been proposed over the last few decades to forecast air temperature.
  • 3.0K
  • 11 Jan 2022
Topic Review
Sludge Treatment Reed Beds
Sludge Treatment Reed Beds (STRB) represent a state-of-the-art nature-based solution to sludge treatment and management. It is an effective, economical (i.e., of low investment, operation and maintenance cost, and low energy consumption), environmentally friendly, and technically efficient technology. In STRBs, the sludge is applied to a growing stand of reeds under controlled conditions. The method relies on the exploitation of the transpiring and aerating capabilities of the reeds, which absorb moisture and nutrients from the sludge for their growth. Additionally, the sludge is dewatered by drainage through the underlying gravel layers, and evaporation from the sludge surface. In the long run, the sludge is oxidized and its organic matter content decreases. The final solids content of the dewatered sludge can build up to and exceed 40%, depending on the sludge loading rate and the climate. STRB operational life is usually at least 30 years and is divided into two or three operational phases of 8-12 years. At the end of each operational phase, the accumulated residual sludge is removed and recycled typically in agriculture and the STRB is emptied.
  • 3.0K
  • 01 Apr 2021
Topic Review
Winkler Index
The Winkler Index, sometimes known as the Winkler Scale or Winkler Regions, is a technique for classifying the climate of wine growing regions based on heat summation or growing degree-days. In the system, geographical areas are divided into five climate regions based on temperature converted to growing degree-days, and is commonly known as Regions I–V (see below). The system was developed at the University of California, Davis by A. J. Winkler and Maynard Amerine.
  • 3.0K
  • 27 Sep 2022
Topic Review
Impact of Tritium on Living Organisms
Tritium is a byproduct of many radiochemical reactions in the nuclear industry, and its effects on aquatic organisms, particularly low-dose effects, deserve special attention. The low-dose effects of tritium on aquatic microbiota have been intensively studied using luminous marine bacteria as model microorganisms. Low-dose physiological activation has been demonstrated and explained by the signaling role of reactive oxygen species through the “bystander effect” in bacterial suspensions. The activation of microbial functions in natural reservoirs by low tritium concentrations can cause unpredictable changes in food chains and imbalances in the natural equilibrium. The incorporation of tritium from the free form into organically bound compounds mainly occurs in the dark and at a temperature of 25 °C. When tritium is ingested by marine animals, up to 56% of tritium is accumulated in the muscle tissue and up to 36% in the liver. About 50% of tritium in the liver is bound in non-exchangeable forms. Human ingestion of water and food products contaminated with background levels of tritium does not significantly contribute to the total dose load on the human body. 
  • 3.0K
  • 22 Apr 2022
Topic Review
Natural Gas Conversion Technologies
Natural gas is a fossil fuel-based energy resource that is abundant in nature. It is a mixture of various components, predominantly methane. Natural gas has wide applications in the industries, residential buildings for heating, electricity generation, as a transportation fuel, and for various commercial purposes. The use of natural gas for electric power generation offers several advantages compared to other fossil fuels.
  • 3.0K
  • 13 Apr 2021
Topic Review
Environmental Aspects of Potash Mining
Verkhnekamskoe potash deposit. The deposit is located in the central part of the Solikamsk depression in the Pre-Ural foredeep (Perm Krai, Russia). All the main features and problems of underground mining of water-soluble ores and potassium fertilizer production are considered using the example of one of the world’s largest potash deposits.
  • 3.0K
  • 03 Apr 2023
Topic Review
The Shift Project
The Shift Project (also called The Shift or TSP) is a French nonprofit created in 2010 that aims to limit both climate change and the dependency of our economy on fossil fuels.
  • 3.0K
  • 02 Dec 2022
Topic Review
Nitrogen in Wetlands
Wetlands are viable sinks for nitrate and have also been identified as a source of nitrous oxide, a product of two microbially regulated processes: nitrification and denitrification. Anthropogenic expansion of nitrogen is a leading cause of the eutrophication of water bodies and may also contribute to the deterioration of the ozone layer in the stratosphere. Wetlands ameliorate the quality of water percolating through them, by retaining nutrients and sequestering carbon, and simultaneously enhancing the flora and fauna diversity of these landscapes. Among the many services these wetlands provide, they also alleviate nitrate pollution by attenuating reactive nitrogen from agricultural drainage and ensure the effective reclamation of the wastewater. 
  • 3.0K
  • 24 May 2021
Topic Review
Phenol
Phenol and its derivatives are hazardous, teratogenic and mutagenic, and have gained significant attention in recent years due to their high toxicity even at low concentrations. Phenolic compounds appear in petroleum refinery wastewater from several sources, such as the neutralized spent caustic waste streams, the tank water drain, the desalter effluent and the production unit. Therefore, effective treatments of such wastewaters are crucial. Conventional techniques used to treat these wastewaters pose several drawbacks, such as incomplete or low efficient removal of phenols.
  • 3.0K
  • 30 Aug 2021
Topic Review
Climate Change in Vietnam
Vietnam is considered, in coming decades, to be among the most affected countries by global climate change. A large number of studies that Vietnam is experiencing climate change and will be severely negatively affected in coming decades. These negative effects include sea level rise, salinity intrusion and other hydrological problems like flood, river mouth evolution, sedimentation as well as the increasing frequency of natural hazards such as cold waves, storm surges will all exert negative effects on the country's development and economy including agriculture, aquaculture, road infrastructure, etc. Some issues, such as land subsidence (caused by excessive groundwater extraction) further worsen some of the effects climate change will bring (sea level rise) especially in areas such as the Mekong Delta. The government, NGOs, and citizens have taken various measures to mitigate and adapt to the impact.
  • 3.0K
  • 14 Nov 2022
Topic Review
Granular Organic Fertilizers
Granular organic fertilizers' production has recently become more popular, with the main aim of converting high-moisture organic matter, such as manure, manure mixtures, meat and bone waste or other organic matter, into pellets that are convenient to spread in the field. The pellets are usually produced with the diameter of 4 or 6 mm so that they can be easily spread with mineral or organic fertilizer spreaders. Once in the soil, organic fertilizer pellets become wet, decompose and release nutrients.
  • 3.0K
  • 11 Sep 2021
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